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V.W. Rusch



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    MO01 - Lung Cancer Biology - Techniques and Platforms (ID 90)

    • Event: WCLC 2013
    • Type: Mini Oral Abstract Session
    • Track: Biology
    • Presentations: 1
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      MO01.04 - Comparison of Microarray and RNA Sequencing Platforms for Profiling MicroRNAs in Formalin-Fixed, Paraffin-Embedded Non-Small Cell Lung Cancer Specimens (ID 3145)

      10:30 - 12:00  |  Author(s): V.W. Rusch

      • Abstract
      • Slides

      Background
      MicroRNAs are useful biomarkers for various disease states, and their preservation in formalin-fixed, paraffin-embedded (FFPE) tissue makes them particularly useful for clinicogenetic studies. Although global microRNA expression in FFPE samples is routinely measured with microarrays, the utility of RNA sequencing for such profiling has yet to be established. In this study, to appraise the suitability of RNA sequencing, microRNAs in RNA from lung cancer FFPE samples were quantified by both a microarray and a sequencing platform.

      Methods
      The affinity spin column–based Roche High Pure FFPE RNA kit was used to extract total RNA from 8 resected stage I lung adenocarcinoma FFPE tumor specimens (~3 mm[3]) with ≥50% tumor content. RNA was quantified by RiboGreen fluorometric and absorbance spectrometric analysis at 260 nm, and its quality was examined by electrophoresis on an RNA Pico chip in an Agilent Bioanalyzer 2100. MicroRNAs in 120 ng of RNA were profiled using the 8x60K Agilent Human miRNA Microarray (release 16.0) platform. MicroRNAs were also quantified by use of the Illumina HiSeq 2000 sequencing system (1x 50 bp reads), with multiplexed sequencing libraries prepared using 1 ug of RNA with the Illumina Truseq Small RNA Preparation Kit (version 2.0). Microarray data were processed using the AgiMicroRna Bioconductor package in R. Sequencing data were demultiplexed using CASAVA software and were mapped against mature human microRNAs in the miRBase database (version 16) using STAR aligner software. Absolute microRNA count values were then normalized among samples by use of the edgeR Bioconductor package.

      Results
      Results of RiboGreen fluorometric analysis suggested that an average of 16 ug (range, 6-35 ug; SD, 8 ug) of RNA was obtained from the FFPE specimens. Significant degradation of RNA was observed, as expected, with Bioanalyzer RNA integrity number values between 1.9 and 2.5. An average of 1.3 million sequencing reads (range, 9.1-16.9 million; SD, 3.5 million) were obtained, but only 1.4% (range, 0.4%-2.1%; SD, 1.4%) of them mapped to known microRNAs. Of the 1205 human microRNAs detectable with the microarray platform, 302 were identified as expressed in the 8-sample set, and 593 were identified as expressed in the sequencing platform. For the 177 microRNAs detected by both microarray and sequencing methods, the interplatform Spearman correlation coefficient was >0.5 for only 51 of them. Reverse-transcription PCR assays are being performed to identify the platform that yields the most accurate microRNA profile.

      Conclusion
      MicroRNA profiling by RNA sequencing and microarray techniques produced different results. The RNA sequencing method described here does not appear to be suitable for profiling microRNAs in RNA from FFPE samples. It is possible that depletion of ribosomal RNA fragments from FFPE RNA samples may improve the quality of data obtained from RNA sequencing.

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    MO09 - Mesothelioma I (ID 120)

    • Event: WCLC 2013
    • Type: Mini Oral Abstract Session
    • Track:
    • Presentations: 1
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      MO09.04 - Defining BAP1 Syndrome: Preliminary results from an epidemiologic ascertainment study (ID 3437)

      16:15 - 17:45  |  Author(s): V.W. Rusch

      • Abstract
      • Presentation
      • Slides

      Background
      Identifying tumorigenic mutations in malignant pleural mesothelioma (MPM) is essential to advance therapy. Somatic mutations in the BRCA-1 associated protein-1 (BAP1) gene occur in about 20% of MPM tumors (Bott et al., Nature Genetics, 2011). In a retrospective analysis evaluating demographics, exposures, and survival, a history of smoking was the only clinical feature associated with the presence of BAP1 mutations (Zauderer et al., in press, J Thorac Oncol, 2013). Germline BAP1 mutations have also been identified in families predisposed to MPM (Testa et al., Nature Genetics, 2011). BAP1 germline mutations have also been associated with other tumors including atypical Spitz nevi, uveal melanoma, and renal cell carcinoma. These discoveries suggest that BAP1 mutations in mesothelioma represent part of a new hereditary cancer syndrome but the exact clinical phenotype remains unclear. To establish the frequency of germline BAP1 mutations in MPM patients and to accurately assess exposure history and family histories in these patients, we have undertaken a clinical trial to prospectively collect this information from patients with MPM.

      Methods
      All consenting patients provide a saliva or blood specimen from which germline DNA is extracted. Existing tumor samples are collected and analyzed for BAP1 mutation. Everyone completes a questionnaire regarding asbestos exposure, personal cancer history, and family history of malignancy. First, we will perform a de-identified assessment of the prevalence of germline BAP1 mutation. Patients whose tumors harbor BAP1 mutation and/or meet prespecified high risk criteria will be approached for identified germline testing after appropriate pre-test counseling. Mutations identified through research testing with be confirmed with clinical testing and additional genetic counseling will be undertaken. Testing will be offered to family members of patients with identified BAP1 germline mutations. Please see Figure 1 for study flow. Figure 1

      Results
      During the first 3 months that this protocol was open, we accrued 26 patients with mesothelioma, 15 of whom qualify for identified research testing. We will present results from ongoing testing at the meeting.

      Conclusion
      Recruiting patients to perform both de-identified and identified germline testing is feasible. Given the paucity of information regarding penetrance and appropriate screening interventions, BAP1 germline testing should continue only in the context of research programs. Additional preclinical work is ongoing to exploit this potential therapeutic target. Supported, in part, by a grant from the Mesothelioma Applied Research Foundation.

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    MO14 - Mesothelioma II - Surgery and Multimodality (ID 121)

    • Event: WCLC 2013
    • Type: Mini Oral Abstract Session
    • Track: Mesothelioma
    • Presentations: 1
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      MO14.11 - Safety of hemithoracic pleural intensity-modulated radiation therapy (IMRT) for malignant pleural mesothelioma (MPM) in the multimodality setting: interim analysis of a phase II study. (ID 2802)

      10:30 - 12:00  |  Author(s): V.W. Rusch

      • Abstract
      • Presentation
      • Slides

      Background
      Pleurectomy/decortication (P/D) is increasingly used for the surgical management of MPM. The presence of the remaining ipsilateral lung poses a challenge when delivering adjuvant radiation therapy, as the risk for radiation pneumonitis (RP) is high. We developed an IMRT technique targeting the entire pleura of the involved hemithorax, with promising early results. Here, we present the interim results of a prospective phase II study to determine the safety and toxicity profile of pleural IMRT following induction chemotherapy and P/D.

      Methods
      Twenty-nine patients with locally advanced MPM have been enrolled to date. All patients received up to four cycles of pemetrexed/platinum chemotherapy. P/D was performed for all resectable patients. Sequential hemithoracic pleural IMRT was then administered with the intent of achieving a total planned dose of 50.4Gy in 28 fractions, as previously described (Rosenzweig et al., IJROBP 2012). All patients were simulated with a 4D-CT scan. A PET scan for image fusion and radiation planning was available for all patients. A Simon two-stage design was applied. A safety analysis after the first 9 patients led to the identification of only one case with ≥grade 3 RP in the first 3 months. The cohort was therefore expanded to 28 evaluable patients, defined as having initiated RT. The primary endpoint is the incidence of ≥grade 3 RP defined per Common Terminology Criteria for Adverse Events, v4.0. Steroids are typically initiated for ≥grade 2 RP.

      Results
      To date, 21 out of 29 patients total are evaluable. The median follow-up is 10 months. The median age at diagnosis is 66 years (range 38-79). Median KPS was 90% (range 70-90%). Three patients had sarcomatoid, 3 had biphasic and 23 had epithelioid MPM. All patients received chemotherapy. Eight patients (28%) had a partial response, nine patients (38%) progressed, and all others had stable disease. Twenty-four patients (83%) underwent surgical exploration. Five patients underwent an extended P/D or P/D, 11 had a partial P/D, and 8 were found to be unresectable. Eight patients were removed from the study prior to receiving IMRT (7 due to disease progression and 1 due to grade 4 pulmonary embolism after one cycle of chemotherapy). To date, nineteen patients have completed IMRT [median dose 4680cGy (range 4500 to 5040cGy)]; one patient had distant disease progression after 16 fractions; one patient is currently on treatment. Five patients experienced grade 2 RP that was successfully controlled with steroids. One patient experienced grade 3 RP requiring supplemental oxygen, but quickly improved after steroid initiation. Other commonly observed ≥grade 2 radiation-related toxicities included fatigue (37%), dyspnea (47%), nausea (42%), esophagitis (26%), and cough (11%). No grade 4 or 5 radiation-related toxicities were observed.

      Conclusion
      Hemithoracic pleural IMRT appears to have an acceptable toxicity profile in this ongoing phase II study. Early intervention with steroids is effective in controlling RP. This novel radiation technique has great promise as a component of lung-sparing multi-modality therapy in locally advanced MPM.

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    MO19 - Lung Cancer Immunobiology (ID 91)

    • Event: WCLC 2013
    • Type: Mini Oral Abstract Session
    • Track: Biology
    • Presentations: 2
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      MO19.02 - The Tumor Immune Microenvironment in Octogenarians with Stage I Non-Small Cell Lung Cancer: Implications for Immunotherapy (ID 3155)

      10:30 - 12:00  |  Author(s): V.W. Rusch

      • Abstract
      • Presentation
      • Slides

      Background
      The elderly have less-robust immune responses to infections, immunizations, and tumors, compared with younger people. Furthermore, preclinical studies have indicated that immunotherapeutic interventions are less effective in older animals. Considering the effects of age-associated changes in immune function, most clinical trials of cancer-related immunotherapy have been conducted in relatively young patients. With the increasing focus on immunotherapy for non-small cell lung cancer (NSCLC), we investigated the relationship between patient age and tumor immune parameters in stage I NSCLC.

      Methods
      Tissue microarrays from patients with stage I NSCLC (n=1371; 1995-2009; median follow-up, 3.5 years) were constructed, and immunohistochemical analyses for immune cell infiltration (CD3, CD4, CD8, CD20, FoxP3) were performed. Patients were categorized into 3 groups: (1) ≤65 years old, (2) 66-79 years old, and (3) ≥80 years old. Stains were analyzed for immune cell infiltration (low vs high) in the tumor nest. The Chi-Square test was used to analyze the association between immune parameters and age group. The Kaplan-Meier method was used to estimate recurrence-free survival (RFS).

      Results
      In total, 1116 patients with stage I lung adenocarcinoma and 255 patients with stage I squamous cell carcinoma were enrolled. Patients aged ≥80 years did not have a significantly poorer prognosis (n=155; 5-year RFS, 76.0%) than the patients in the two younger groups (p=0.65; Figure 1A). There were no statistically significant differences in numbers of tumor-infiltrating lymphocytes in the tumor nest between the three groups (Figure 1B), nor was there a statistically significant difference between the elderly group and the younger patients when effector regulatory immune response ratios were compared (FoxP3/CD3 ratio; high vs low, p=0.85). Figure 1

      Conclusion
      In this large cohort of stage I NSCLC patients selected for surgical resection, the tumor microenvironment among elderly patients resembles other age groups. Our study provides important information while considering immunotherapy in elderly patients with lung cancer.

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      MO19.12 - Prognostic Impact of Tumor-Infiltrating Immune Cells in Lung Squamous Cell Carcinoma (ID 2896)

      10:30 - 12:00  |  Author(s): V.W. Rusch

      • Abstract
      • Presentation
      • Slides

      Background
      The prognostic significance of the tumor immune microenvironment in lung adenocarcinoma has been established by us (CCR 2011, JCO 2013, Oncoimmunology 2013) and others. Here, we investigate whether tumor-infiltrating immune cells correlate with prognosis, independent from TNM staging, in lung squamous cell carcinoma (SCC).

      Methods
      All available tumor slides from therapy-naive, surgically resected solitary lung SCCs (n=485; 1999-2009) were reviewed. Tissue microarrays were constructed using 451 cases (stage I, 255; II, 131; III, 65) from 3 representative tumor areas. Immunostaining for CD3 (pan T cell marker), CD45RO (memory T cell), CD8 (cytotoxic T cell), CD4 (helper T cell), FoxP3 (regulatory T cell), CD20 (B cell), CD68 (macrophage), and CD10 (neutrophil) was performed. For each case, the average number of cells positive for T cell markers was recorded as the ratio to CD3+ lymphocytes, and classified as low or high by use of the median. CD20, CD68, and CD10 were classified as low or high by the number of positive cells (≥20, ≥50, and ≥10, respectively) as our recent publication (JCO 2013). Overall survival (OS) was estimated using the Kaplan-Meier method; multivariate analyses were performed using the Cox proportional hazards model.

      Results
      Five-year OS was 59% for the entire cohort and 68% for stage I patients. Analysis of single immune cell infiltration revealed that high CD10+ neutrophil count was correlated with lower OS (5-year OS, 53%; n=160) than low CD10+ count (5-year OS, 61%; n=286; p=0.006). Analysis of biologically relevant immune cell combinations identified 2 significant factors of prognosis: (1) patients with high CD4+ and high FoxP3+ T cell ratios had worse prognosis (5-year OS, 52%; n=140) than the other groups (5-year OS, 62%; n=304; p=0.008), and (2) patients with high CD10+ neutrophil and low CD20+ B lymphocyte counts had worse prognosis (5-year OS, 43%; n=102) than the other groups (5-year OS, 63%; n=340; p<0.001). These results were confirmed in a subgroup analysis limited to stage I patients (p=0.020 for high CD4/high FoxP3+ ratios; p=0.007 for high CD10+/low CD20+ counts). In multivariate analysis, high CD4+/high FoxP3+ ratios (HR=1.58; p=0.001) and high CD10+/low CD20+ counts (HR=1.71; p<0.001) remained significantly associated with poorer survival (Table).

      Table. Multivariate analysis for overall survival
      Variable HR 95% CI p
      High CD4+/high FoxP3+ ratios 1.58 1.21–2.06 0.001
      High CD10+/low CD20+ counts 1.71 1.28–2.27 <0.001
      Age (>65 years old) 1.51 1.09–2.09 0.014
      Sex (male vs. female) 1.31 1.01–1.69 0.043
      Smoking pack years (>90) 1.01 1.00–1.01 0.003
      Stage (II and III vs. I) 1.53 1.16–2.02 0.002
      Lymphovascular invasion 1.38 1.02–1.88 0.040

      Conclusion
      High CD4+/high FoxP3+ ratios and high CD10+/low CD20+ counts are significant factors of prognosis for lung SCC, independent of TNM staging. Targeting regulatory T cells or enhancing tumor-specific B-cell responses may thus have applicability for the treatment of lung SCC.

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    MO26 - Anatomical Pathology II (ID 129)

    • Event: WCLC 2013
    • Type: Mini Oral Abstract Session
    • Track: Pathology
    • Presentations: 2
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      MO26.03 - In Patients with Stage I Lung Adenocarcinoma, Tumor Budding Is a Significant Prognostic Factor for Recurrence, Independent of the IASLC/ATS/ERS Classification, and Correlates with a Protumor Immune Microenvironment (ID 2917)

      10:30 - 12:00  |  Author(s): V.W. Rusch

      • Abstract
      • Presentation
      • Slides

      Background
      In 2011, the IASLC/ATS/ERS proposed a new classification for lung adenocarcinoma (ADC) that has powerful prognostic value. However, tumors in each subtype may still include heterogeneous prognostic subgroups - especially in the acinar, papillary, and solid subtypes, in which the majority of tumors are classified. Recently, immune markers such as CD markers and cytokines have been identified as prognostic factors in lung cancer. In this study, we investigate whether tumor budding further stratifies prognosis for stage I lung ADC, independent of the IASLC/ATS/ERS classification, and whether it correlates with prognostic immune markers.

      Methods
      All available tumor slides from patients with therapy-naive, surgically resected solitary stage I lung ADC (1995-2009) were reviewed (n=1038). Tumors were classified according to the IASLC/ATS/ERS classification. Mitoses were counted at 10 high-power fields (HPFs) (x400 magnification). Tumor budding (tumor nest composed of <5 cells) was assessed, at 10 HPFs (x200 magnification), in areas with the smallest tumor nests and was graded by the maximum number of budding : 0, 0/HPF; 1, 1-4/HPF; 2, 5-9/HPF, and 3, ≥10/HPF. Tissue microarrays were constructed from tumoral and stromal cores, and immunostaining for CD3, FoxP3, IL-7R, and IL-12Rβ2 was performed. Lymphocytes positive for CD3 and FoxP3 were scored in tumor and stroma, and tumors were classified using our recently reported FoxP3/CD3 risk index (JCO 2013). Tumoral expression of IL-7R and IL-12Rβ2 was dichotomized by the sum of intensity (0-3) and distribution (1, 1%-50%; 2, >50%) scores: negative (total score <1) and positive (≥1). Recurrence-free probability (RFP) was estimated using the Kaplan-Meier method; multivariate analyses were performed using the Cox proportional hazards model.

      Results
      RFP was lowest for patients with budding grade 3 (n=180; 5-year RFP, 69%; p<0.001), followed by grade 2 (n=139; 75%), 1 (n=189; 81%), and 0 (n=530; 89%). Budding grade was dichotomized into negative (grades 0-1) or positive (grades 2-3) using colorectal cancer criteria. The RFP for patients with positive budding (n=319; 5-year RFP, 72%) was significantly lower than that for patients with negative budding (n=719; 87%; p<0.001), which was confirmed in a subgroup analysis limited to stage IA (p=0.004) and IB (p<0.001) patients. Tumor budding further stratified RFP in patients with acinar (p<0.001), papillary (p=0.027), and solid (p=0.015) tumors. Budding was more frequently observed in tumors with high-grade histology (solid and micropapillary; p<0.001), lymphovascular invasion (p<0.001), and high mitotic count (p<0.001). Tumor budding was positively correlated with stromal CD3+ lymphocytes (p<0.001), stromal FoxP3+ (p<0.001), FoxP3/CD3 risk index (high FoxP3, low CD3) in stroma (p<0.001), and tumoral IL-7R expression (p<0.001). In multivariate analysis, tumor budding was an independent prognostic factor for recurrence (HR=1.13; p=0.002).

      Conclusion
      Tumor budding was a significant prognostic factor in stage I lung ADC, independent of IASLC/ATS/ERS classification, and it correlated with a protumor immune microenvironment (high FoxP3+ lymphocyte infiltration and high IL-7R expression). These findings may inform therapeutic decisions and stratify patients for additional therapy, including immunotherapy.

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      MO26.04 - Reclassification of Resected Non-Small Cell Lung Carcinomas Originally Diagnosed as Squamous Cell Carcinoma, after Reevaluation Using Immunohistochemical Analysis (p40, p63, TTF-1, and Napsin A): Memorial Sloan-Kettering Cancer Center Experience (ID 2905)

      10:30 - 12:00  |  Author(s): V.W. Rusch

      • Abstract
      • Presentation
      • Slides

      Background
      Currently, non-small cell lung carcinomas (NSCLCs) are mainly classified by histologic analysis and mucin staining: (1) squamous cell carcinoma (SCC) shows keratinization and intercellular bridges; (2) adenocarcinoma shows lepidic, acinar, papillary, micropapillary, or solid pattern, with mucin production; and (3) large cell carcinoma lacks these findings. However, recent studies have shown promising improvements in the classification of NSCLC with immunostain-based markers, including p40 and thyroid transcription factor–1 (TTF-1). In this study, we investigate the use of immunohistochemical analysis in reclassifying NSCLCs originally diagnosed as SCCs.

      Methods
      All available tumor slides from patients with therapy-naive, surgically resected solitary NSCLCs originally diagnosed as SCC (1999-2009) were reviewed. Tissue microarrays were constructed with 3 cores (n=480), and immunostaining for p40, p63, TTF-1 (clone 8G7G3/1), TTF-1 (SPT24), napsin A, chromogranin A, synaptophysin, and CD56 was performed. Immunoreactivity was scored semiquantitatively by staining intensity (weak, moderate, or strong) and percentage of positive tumor cells (diffuse, ≥50%; focal, <50%). Tumors were first grouped by p40 and TTF-1 (8G7G3/1) status: (1) group A (favor SCC): p40 (+) and TTF-1 (8G7G3/1) (-); (2) group B (favor adenocarcinoma): p40 (- or +) and TTF-1 (8G7G3/1) (+); and (3) group C (favor large cell carcinoma): p40 (-) and TTF-1 (8G7G3/1) (-). Immunostain-based tumor classification was then confirmed with histologic findings and other markers.

      Results
      In group A (n=448), 1 tumor was reclassified as adenosquamous carcinoma by histologic findings and focal immunoreactivity for p40, p63, and TTF-1 (SPT24). In group B (n=15), 2 tumors were reclassified as large cell neuroendocrine carcinoma (LCNEC) by neuroendocrine morphologic findings and differentiation (1 as pure LCNEC and the other as combined LCNEC with SCC). In group C (n=17), 6 tumors were confirmed as large cell carcinoma because they lacked adenocarcinoma morphology and TTF-1 [SPT24] expression (2 of these showed focal p63 reactivity without keratinization); 4 were reclassified as large cell carcinoma (favor adenocarcinoma) because they were focally positive for TTF-1 (SPT24) but negative for TTF-1 (8G7G3/1) and napsin A; 2 were reclassified as adenocarcinoma because they were diffusely and strongly positive for TTF-1 (SPT24) but focally (<10%) positive for p63, without keratinization; 3 were reclassified as LCNEC by neuroendocrine morphologic findings and differentiation; and 2 were reclassified as small cell carcinoma by morphologic findings. All tumors finally diagnosed as SCC (n=447) using histologic findings and immunohistochemical analysis were positive for p40 and p63. Among them, 27 tumors were positive for TTF-1 (SPT24) (19 focally and 8 diffusely) but negative for TTF-1 (8G7G3/1), with all showing clear squamous morphologic pattern, thus verifying the greater specificity of the TTF-1 8G7G3/1 clone in SCC.

      Conclusion
      After immunohistochemical reevaluation of 480 NSCLCs originally diagnosed as SCC by classical morphologic analysis, 33 (7%) were reclassified as other histologic types. Immunohistochemical analysis may provide additional valuable information to achieve an accurate diagnosis, particularly in poorly differentiated NSCLCs and in tumors for which the diagnosis of nonkeratinizing SCC is considered.

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    O02 - NSCLC - Combined Modality Therapy I (ID 111)

    • Event: WCLC 2013
    • Type: Oral Abstract Session
    • Track: Combined Modality
    • Presentations: 1
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      O02.05 - Major pathologic response (≤10% viable tumor) following neoadjuvant chemotherapy as a surrogate for overall survival in patients with pathologically documented stage IIIA (N2) lung adenocarcinomas (ID 2345)

      10:30 - 12:00  |  Author(s): V.W. Rusch

      • Abstract
      • Presentation
      • Slides

      Background
      Neoadjuvant chemotherapy improves overall survival in patients with resectable stage IIIA lung adenocarcinomas. The gold-standard endpoint for clinical trials evaluating curative therapies is overall survival. Unfortunately, these trials take nearly a decade to complete and this prolonged timeline hinders the approval of promising therapies in the curative realm. Alternative endpoints that can act as a surrogate for overall survival have been evaluated, including nodal downstaging, nodal clearance, and pathologic response. We evaluated the degree to which these endpoints associate with overall survival in patients with pathologically proven stage IIIA(N2) lung adenocarcinoma treated with neoadjuvant chemotherapy.

      Methods
      An electronic database search engine was used to identify all patients with resectable stage IIIA(N2) lung adenocarcinoma treated with neoadjuvant chemotherapy at Memorial Sloan-Kettering Cancer Center between 1/2007-8/2012. Nodal downstaging was defined as no residual tumor tissue in the N2 nodes. Nodal clearance was defined as no residual tumor tissue in N1 and N2 nodes. Pathologic response was systemically assessed by a dedicated thoracic pathologist (WDT) who reviewed at least 1 section per centimeter of greatest gross tumor diameter. The percent viable tumor tissue in each slide was estimated to the nearest 10%. Major pathologic response (MPR) was defined as ≤10% viable tumor tissue. All pathologic analyses were performed by a dedicated thoracic pathologist (WDT). Patients with residual N2 disease at resection were offered post-operative radiation and routinely monitored thereafter. Survival proportions were estimated by the Kaplan-Meier method and compared using the log-rank test.

      Results
      69 patients with pathologically confirmed IIIA(N2) disease were identified and 46 (67%) ultimately underwent R0 resection. Among these patients, 16 had nodal downstaging, 14 had nodal clearance and 5 had a MPR. In both intention to treat analyses (N=69) and including only those who underwent resection, only MPR significantly associated with overall survival. The table below details findings from the population who had complete cancer resection.

      Endpoint (N=46) Yes (A) No (B) NA (C) HR (95% CI) ITT (A vs B+C) HR (95% CI) Resected(A vs B)
      Nodal downstaging 16 30 23 0.68 (0.32-1.56) 0.73 (0.24-2.10)
      Nodal clearance 14 32 23 0.57 (0.27-1.36) 0.96 (0.32-2.81)
      MPR 5 41 23 0.28 (0.1-0.78) 0.26 (0.07-0.95)
      NA = not assessable; ITT = intention to treat

      Conclusion
      MPR (≤10% viable tumor) effectively identifies patients with good clinical outcomes after neoadjuvant chemotherapy and can serve as a surrogate endpoint for overall survival. Furthermore, lack of MPR identifies a patient population at high risk of recurrence. Neither nodal downstaging nor nodal clearance effectively discriminated those with improved survival. Adaptive clinical trials designed to target those not achieving MPR are encouraged in attempt to improve the rate of cure in this disease.

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    O08 - Preclinical Therapeutic Models I (ID 92)

    • Event: WCLC 2013
    • Type: Oral Abstract Session
    • Track: Biology
    • Presentations: 2
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      O08.02 - Critical Role of CD28 Costimulation in Tumor-Targeted T-cell Therapy Clinical Trial for Pleural Malignancies (ID 2995)

      16:15 - 17:45  |  Author(s): V.W. Rusch

      • Abstract
      • Presentation
      • Slides

      Background
      Successful translation of adoptive T-cell therapy for solid cancers is predicated on the ability to generate a potent antitumor immune response and establish T-cell persistence. Thoracic malignancies typically lack expression of costimulatory ligands but do express negative regulators of T- cell function—factors that may impede T-cell therapy. We hypothesized that cancer antigen–targeted T cells engineered with activating CD28 costimulatory signaling would eradicate tumor and establish long-term functional persistence.

      Methods
      Mesothelin-specific chimeric antigen receptors (CARs) were engineered without (Mz) or with (M28z) a CD28 costimulatory domain. CAR-transduced human T cells were evaluated in vitro for cytotoxicity ([51]Cr-release assay), cytokine release (Luminex cytokine-release assay), and proliferation (cell-counting assay). In vivo assessment included monitoring of tumor progression by bioluminescence imaging (BLI), flow cytometric analysis of splenic/peripheral blood T-cell phenotypes, and Kaplan-Meier analysis of median survival, in NOD-scid IL-2Rγ-null mice bearing orthotopically implanted mesothelin-expressing mesothelioma cells (MSTO-211H: CD80/86-, TGF-β+, PD-L1+) and treated with human T cells transduced to express either Mz, M28z, or a control vector.

      Results
      In vitro, M28z CAR–transduced T cells exhibited equivalent cytotoxicity but enhanced Th1 cytokine secretion and antigen-specific proliferation, compared with Mz transduced T cells. In vivo, mice treated with a single low dose of M28z CAR–transduced T cells achieved tumor eradication and prolonged survival (median survival not reached; p=0.01), compared with mice treated with an equal dose of Mz-transduced (median survival, 63 days; tumor eradication in 20% of mice) or control CAR–transduced (median survival, 36 days) T cells (Figure 1A, 1B). Furthermore, CD28 costimulation enhanced CD62L[-]CD45RA[-] effector memory T-cell persistence (Figure 1C), leading to a robust T-cell proliferative response and superior control of tumor burden on tumor rechallenge 87 days after T-cell administration (Figure 1D, 1E). Figure 1

      Conclusion
      CD28 costimulation plays an important role in achieving long-term antitumor efficacy and functional persistence in mesothelin-targeted T-cell therapy. These data provide the scientific rationale for our upcoming clinical trial for pleural malignancies.

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      O08.03 - T-cell Imaging to Noninvasively Monitor Adoptive T-cell Therapy for Thoracic Malignancies (ID 2994)

      16:15 - 17:45  |  Author(s): V.W. Rusch

      • Abstract
      • Presentation
      • Slides

      Background
      Noninvasive T-cell imaging technology allows monitoring of adoptive T-cell responses without the need for invasive biopsies. Herein, we report dynamic imaging of tumor-targeted T cells in preclinical models by use of luminescent-enhanced firefly luciferase vector, and we further demonstrate the successful use of a clinical-grade herpes simplex virus type 1 thymidine kinase (HSV1-tk)–incorporated vector for monitoring of T-cell trafficking, antigen-specific proliferation, and biodistribution.

      Methods
      T cells transduced with mesothelin-targeted chimeric antigen receptors (M28z) were either cotransduced with an enhanced firefly luciferase vector (effLuc-M28z) or singly transduced with HSV1-tk-M28z (TK-M28z). To simultaneously visualize tumor during T-cell PET imaging, cancer-cell imaging was performed using MSTO-GFP/ffLuc+ (MSTO-211H cells transduced to express mesothelin and the green fluorescent protein/firefly luciferase fusion protein). In vitro, uptake of [18]F-FEAU radiotracer by T cells was measured by [3]H channel counting. In vivo studies used either SCID-beige or NSG mice bearing pleural or flank tumors. Bioluminescence imaging (BLI) quantification was determined by the mean number of photons per second in the region of interest. PET imaging with [18]F-FEAU was performed in a 3-dimensional microPET scanner. T-cell imaging results were validated by flow cytometric and immunohistochemical analysis of harvested tissue.

      Results
      Quantification studies showed a linear relationship between photon emission and T-cell number both in vitro and in vivo. In vivo, evaluation of T-cell biodistribution kinetics, by intravenous administration of effLuc-M28z T cells into mice bearing flank tumors, demonstrated initial accumulation of T cells in the lungs, liver, and spleen and progressive accumulation in the tumor (Figure 1A). Pleurally administered effLuc-M28z+ T cells displayed an increasing BLI signal (5-fold; p<0.01) in response to antigen 72 hours after administration, compared with pleurally administered effLuc+ T cells alone (control) (Figure 1B). T-cell accumulation in pleural tumor and extrathoracic sites (spleen) was confirmed by flow cytometric analysis of tissues harvested at serial time points (Figure 1C). These results were reproduced with clinical-grade vector TK-M28z+ T cells administered intrapleurally in mice bearing pleural tumor. Serial [18]F-FEAU PET imaging showed antigen-specific T-cell accumulation with decreasing tumor burden, as seen by corresponding tumor BLI (Figure 1D). Figure 1

      Conclusion
      We provide an optimized method for monitoring of T-cell trafficking, localization and proliferation in thoracic malignancies. Our findings—derived using a clinical-grade imaging construct and substrate—provide convincing evidence for the use of noninvasive T-cell monitoring in our upcoming adoptive T-cell therapy clinical trial.

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    O09 - General Thoracic Surgery (ID 100)

    • Event: WCLC 2013
    • Type: Oral Abstract Session
    • Track: Surgery
    • Presentations: 1
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      O09.01 - Sites, Symptoms, CT Scan Findings and Survival in Patients with Recurrence After Curative-Intent Surgical Resection for Stage I Lung Adenocarcinoma (ID 2907)

      16:15 - 17:45  |  Author(s): V.W. Rusch

      • Abstract
      • Presentation
      • Slides

      Background
      The purpose of this study is to examine the patterns of recurrence for stage I lung adenocarcinoma and to identify clinicopathologic factors associated with post-recurrence survival (PRS).

      Methods
      We performed a retrospective review of 1027 patients with stage I lung adenocarcinoma who underwent a surgical resection between 1999 and 2009 (median follow-up 35 months). The manner of recurrence detection, either by scheduled CT scan, presentation with new symptoms, or by other means, was noted. Tumors were classified using the new IASLC/ATS/ERS nomenclature and grading as low (adenocarcinoma in situ, minimally invasive adenocarcinoma, or lepidic-predominant), intermediate (papillary-predominant or acinar-predominant), and high (micropapillary-predominant, solid-predominant, colloid-predominant, or invasive mucinous) grade. The Kaplan-Meier method was used to analyze recurrence-free survival (RFS). Log-rank tests and Cox proportional hazard models were used to analyze the association between predictive factors and PRS.

      Results
      Of the 1027 patients with follow-up data available, 151(15%) had recurrent disease (table), five-year RFS was 80%. Of the 151 patients with recurrence, 80 (52%) were detected by a scheduled CT scan (51 locoregional and 29 distant). Symptomatic recurrences were seen in 70 (46%) patients (9 locoregional and 61 distant). Overall, 5-year PRS was 27.8%. On multivariate analysis, recurrences identified by new symptoms (HR, 2.15; 95% CI, 1.36- 3.40; p=0.001), a recurrence free interval ≤ 24 months (HR, 2.52; 95% CI, 1.31- 4.84; p=0.006), and tumors with high architectural grade (HR, 1.69; 95% CI, 1.07- 2.67; p=0.024) and vascular invasion (HR, 1.79; 95% CI, 1.14- 2.81; p=0.012) were significantly associated with a worse PRS (Figure).Figure 1Figure 2

      Conclusion
      Our study demonstrates the recurrence patterns in patients who underwent surgical resection for stage I lung adenocarcinoma. We identify a symptomatic recurrence, a recurrence-free interval ≤ 24 months, high architectural grade, and vascular invasion, as independent factors associated with worse post recurrence survival.

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    O17 - Anatomical Pathology I (ID 128)

    • Event: WCLC 2013
    • Type: Oral Abstract Session
    • Track: Pathology
    • Presentations: 2
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      O17.05 - Accuracy and Interobserver Agreement in Identifying Histologic Subtypes in Stage I Lung Adenocarcinomas ≤3 cm Using Frozen Section (ID 2590)

      10:30 - 12:00  |  Author(s): V.W. Rusch

      • Abstract
      • Presentation
      • Slides

      Background
      The new IASLC/ATS/ERS classification of lung adenocarcinoma (ADC) histologic subtypes is now recommended for prognostic stratification. The ability to determine histologic subtype accurately by frozen section (FS) may help surgeons to choose limited resection versus anatomic resection in the management of lung ADC. The aim of this study is to investigate the accuracy and interobserver agreement of FS for predicting histologic subtype.

      Methods
      FS and permanent section slides from 361 surgically resected stage I lung ADCs ≤3 cm were reviewed for predominant histologic subtype and presence or absence of lepidic, acinar, papillary, micropapillary, and solid patterns. To determine interobserver agreement, 50 cases were additionally reviewed by 3 pathologists. To test the accuracy of FS in determining degree of invasion in cases with predominantly lepidic growth pattern, 5 pathologists reviewed FS slides from 35 patients and attempted to discriminate between adenocarcinoma in situ (AIS), minimally invasive adenocarcinoma (MIA), and lepidic predominant adenocarcinoma (LPA).

      Results

      Parameter Accuracy, % (95% CI) Sensitivity, % (95% CI) Specificity, % (95% CI) κ
      Predominant histologic subtype
      Overall 68 (63–73) Not applicable Not applicable 0.565
      Lepidic 90 (86–92) 75 (64–84) 93 (90–96) 0.681
      Acinar 76 (71-80) 70 (61–77) 79 (73–84) 0.481
      Papillary 85 (81-88) 62 (50–72) 91 (87–94) 0.527
      Micropapillary 94 (91-96) 21 (9–40) 99 (97–100) 0.277
      Solid 91 (88-94) 79 (67–87) 94 (90–96) 0.700
      Presence or absence of each histologic pattern
      Lepidic 80 (76–84) 75 (69–80) 91 (84–96) 0.588
      Acinar 89 (85–92) 90 (86–93) 67 (35–90) 0.252
      Papillary 72 (67–77) 70 (64–75) 79 (69–87) 0.397
      Micropapillary 67 (62–72) 37 (30–45) 94 (89–97) 0.321
      Solid 84 (80–88) 69 (61–76) 96 (92–98) 0.670
      The accuracy of FS for predicting histologic subtype is shown in the Table. There was moderate agreement on the predominant histologic subtype between FS diagnosis and final diagnosis (κ=0.565). FS had high specificity for micropapillary and solid patterns (94% and 96%, respectively), but sensitivity was low (37% and 69%, respectively). The interobserver agreement was satisfactory (κ > 0.6, except for acinar pattern). All cases of AIS were correctly diagnosed using FS. For MIA, only 41.3% of FS diagnoses were correct, and 52% were overdiagnosed as LPA; for cases of LPA, 79% of FS diagnoses were correct.

      Conclusion
      FS can provide information on the presence of aggressive histologic patterns—micropapillary and solid—with high specificity but low sensitivity. FS is not suitable for determining the predominant pattern or degree of invasion. Although FS can be helpful in diagnosing AIS, it has poor accuracy in distinguishing MIA from LPA.

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      O17.06 - Tumor Budding and Nuclear Grade, but not Histologic Subtype, Are Significant Prognostic Factors, Independent of TNM Stage, in Patients with Lung Squamous Cell Carcinoma (ID 2910)

      10:30 - 12:00  |  Author(s): V.W. Rusch

      • Abstract
      • Presentation
      • Slides

      Background
      The new IASLC/ATS/ERS lung adenocarcinoma classification, proposed in 2011, has significant prognostic value. For lung squamous cell carcinoma (SCC), however, no pathologic findings have been widely accepted to predict patient outcomes with the exception of TNM stage. Tumor budding has been recognized as a factor of poor prognosis in colorectal cancer, and nuclear grading has been widely accepted as a prognostic indicator in breast cancer. In this study, we determine whether histologic findings can independently predict prognosis in lung SCC.

      Methods
      All available tumor slides from patients with therapy-naive, surgically resected solitary lung SCC (1999-2009) were reviewed (n=485; stage I/II/III, 281/136/68). Tumors were graded by means of tumor differentiation. Tumors were classified as keratinizing, nonkeratinizing, and basaloid subtypes by presence (≥5%) or absence of keratinization and by predominant (≥50%) basaloid pattern. Tumor budding (tumor nests composed of <5 cells) and presence of single tumor-cell invasion were assessed using 10 high-power fields (HPFs) (x200 magnification) in the areas with the smallest tumor nests. Tumor budding was considered positive when the maximum number of budding was ≥10/HPF. Single tumor-cell invasion was considered positive when it was identified at 10 HPFs. Nuclear diameter was evaluated, at ≥3 HPFs in the largest nuclei, using nearby small lymphocytes as reference and was classified as either large (>4 small lymphocytes) or small (≤4). Overall survival (OS) was estimated using the Kaplan-Meier method, and multivariate analyses were performed using the Cox proportional hazards model.

      Results
      Basaloid subtype correlated with better OS than nonbasaloid subtype (p=0.046). Tumor budding (p<0.001), single tumor-cell invasion (p<0.001), and large nuclei (p=0.005) correlated with worse OS (Table). However, tumor differentiation and presence of keratinization did not correlate with prognosis. The prognostic significance of tumor budding was confirmed in a subgroup analysis limited to stage I (p=0.028) and stage II/III (p=0.008) patients. In addition, basaloid subtype correlated with favorable prognosis (p=0.042), and both single tumor-cell invasion (p=0.014) and large nuclei (p=0.021) were associated with poor prognosis in a subgroup analysis limited to stage I patients. In multivariate analysis, tumor budding (HR=1.04; p=0.024) and large nuclei (HR=1.09; p=0.035) were independent prognostic factors for survival.

      Table. Overall survival by histologic findings
      Histologic finding 5-year OS p
      Subtype Basaloid 69% (n=33) 0.046
      Nonbasaloid 58% (n=452)
      Tumor budding + 39% (n=76) <0.001
      - 62% (n=409)
      Single cell invasion + 47% (n=197) <0.001
      - 67% (n=288)
      Nuclei Large 50% (n=153) 0.005
      Small 63% (n=332)

      Conclusion
      Tumor budding and large nuclei, but not histologic subtype, were significant prognostic factors, independent of TNM stage, for lung SCC. These findings may help to make therapeutic decisions and stratify patients for additional therapy.

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    P1.18 - Poster Session 1 - Pathology (ID 175)

    • Event: WCLC 2013
    • Type: Poster Session
    • Track: Pathology
    • Presentations: 1
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      P1.18-019 - Micropapillary Histology Is Associated with Occult Lymph Node Metastasis (pN2) in Patients with Clinically N2-Negative (cN0/N1) Lung Adenocarcinoma (ID 3232)

      09:30 - 16:30  |  Author(s): V.W. Rusch

      • Abstract

      Background
      Among patients with lung adenocarcinoma staged as N2-negative in the mediastinum by PET/CT scan, up to 16% will have occult N2 metastasis (pN2) detected on mediastinoscopy or surgical resection. We investigated the association between histologic subtyping (according to the newly proposed IASLC/ATS/ERS classification) and occult lymph node metastasis in patients with unsuspected N2 disease.

      Methods
      We performed a retrospective review of 297 patients with lung adenocarcinoma (≤2 cm, 51%; >2 cm, 49%) who underwent surgical resection and mediastinal nodal dissection from 2007 to 2009. Mediastinal lymph node disease was assessed preoperatively by FDG-PET/CT scan. Histologic subtyping was performed according to the newly proposed IASLC/ATS/ERS classification.

      Results
      Ninety-three percent of patients had N0 disease, and 7% had N1 disease, as detected by preoperative PET/CT scan. Of the 297 patients, 32 (10.8%) had occult N2 metastasis identified by pathologic examination (9.7% of patients with cN0 disease, 25% of patients with cN1 disease). On univariate analysis, SUVmax of the primary tumor >4 (p=0.001), predominant histologic subtype (p=0.001), presence or absence of lepidic pattern (p<0.001), micropapillary pattern (p=0.009), and solid pattern (p=0.011) were associated with pN2 disease. On multivariate analysis, presence of lepidic pattern (odds ratio [OR], 0.33; 95% confidence interval [CI], 0.14-0.77; p=0.011), presence of micropapillary pattern (OR, 2.58; 95% CI, 1.13-5.92; p=0.025), and SUVmax of the primary tumor >4 (OR, 2.44; 95% CI, 1.03-5.79; p=0.042) were significantly associated with occult N2 metastasis.

      Conclusion
      Micropapillary histology and primary tumor SUVmax >4 on FDG-PET/CT were independently associated with occult N2 metastasis.

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    P3.09 - Poster Session 3 - Combined Modality (ID 214)

    • Event: WCLC 2013
    • Type: Poster Session
    • Track: Combined Modality
    • Presentations: 1
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      P3.09-005 - "Intention-to-treat" outcomes of sequential patients with stage IIIA lung adenocarcinomas treated with neoadjuvant chemotherapy with intent of surgical resection (ID 1199)

      09:30 - 16:30  |  Author(s): V.W. Rusch

      • Abstract

      Background
      Neoadjuvant chemotherapy followed by surgical resection is uniquely permits assessment of the in vivo response to therapy in patients with IIIA non-small cell lung cancer. Studies of neoadjuvant chemotherapy often focus only on those who are ultimately resected. We describe an “intention-to-treat” analysis of sequential patients with stage IIIA adenocarcinomas receiving neoadjuvant chemotherapy with intent of surgical resection.

      Methods
      Using natural language processing software, we searched the electronic medical record at Memorial-Sloan Kettering Cancer Center for “neoadjuvant,” “preoperative,” or “induction” in physicians’ notes. Cases were limited to those with stage IIIA lung adenocarcinoma deemed resectable by a thoracic surgeon and treated with neoadjuvant chemotherapy (without radiation), including those enrolled in prospective clinical trials. Event-free survival (date of diagnosis to recurrence, relapse or death) and overall survival (date of diagnosis to death) were assessed using Kaplan-Meier methods.

      Results
      From 2007 until 08/2012, 129 patients were identified. Median follow up is 25 months (range 1-76). The patient details are described. 94/129 (73%) were treated with cisplatin-based therapy.Figure 1 The CONSORT diagram below describes the treatment patients ultimately received. Figure 2 The median EFS and OS were 16 (95% CI 13-22) and 44 (95% CI 36-NA) months. OS at 1, 2 and 3-years were 77%, 55%, and 32%. EFS plateaued at 23%, estimating the rate of cure. Overall survival strongly favored surgical resection over salvage radiation (HR=0.5, 95% CI 0.16-1.05).

      Conclusion
      These data provide unique perspective on the outcomes of patients with IIIA adenocarcinoma treated with neoadjuvant chemotherapy with intent of surgical resection. EFS and OS compare favorably to historical outcomes in this stage of disease, demonstrating the value of the neoadjuvant approach. The inferior survival in patients treated with radiation as a “salvage” approach emphasizes the recommendation for definitive concurrent chemoradiation in those unlikely to be resectable.