Virtual Library

Start Your Search

Rowena Yip



Author of

  • +

    ES08 - Critical Concerns in Screening (ID 11)

    • Event: WCLC 2019
    • Type: Educational Session
    • Track: Screening and Early Detection
    • Presentations: 1
    • Now Available
    • +

      ES08.04 - Management Algorithms (Now Available) (ID 3194)

      13:30 - 15:00  |  Author(s): Rowena Yip

      • Abstract
      • Presentation
      • Slides

      Abstract

      Introduction

      Clinical management decisions arising from the first, baseline round of screening for lung cancer are most challenging, as nodules that are seen for the first time may have accumulated over a lifetime and almost all of them are of no clinical concern [1]. In contrast, new or changing findings on subsequent annual repeat low-dose CT scans (LDCTs) have much greater clinical significance.

      Efficiency is particularly important in the baseline round in order to minimize unnecessary harms caused by work-up within the 12 months after the baseline LDCT. Potential workup includes surgery, biopsies, and diagnostic tests requiring intravenous injection (e.g., PET scans, contrast CT). Biopsies and surgery have greater risks than LDCT, and thus the management protocols should aim to minimize these higher risk procedures as much as possible [2]. It is also important not to discourage participants undergoing the baseline round from future participation in annual rounds as these provide the real benefit of annual LDCT screening.

      Methods

      We compared the efficiency of three published baseline LDCT screening protocols [2], the International Early Lung Cancer Action Program (I-ELCAP) [3], American College of Radiology (ACR)-LungRADS [4], and the European Consortium protocols [5] for participants 50 years of age or older with at least 20 pack-years of smoking.

      The three protocols provide recommendations for immediate workup, 3-month and 6-month LDCT as shown in Table 1 [1]. The three protocols use the diameter of the entire solid and nonsolid non-calcified nodule (NCN), but differ for part-solid NCNs. For part-solid NCNs, I-ELCAP uses the diameter of the solid component [6], while ACR-LungRADS uses both the entire diameter of the part-solid NCN as well as the diameter of its solid component. The European Consortium protocol determines the volume of a solid NCN using their software [5], but also specifies the equivalent diameter values for the entire part-solid and nonsolid NCNs as volumetric measurements for these are problematic as was recognized [5]. Measurement error and rounding of measurements are also an important consideration [7,8].

      Efficiency was defined as an efficiency ratio (ER): the number of participants recommended for a particular workup divided by the resulting number of participants diagnosed with lung cancer [2]. An ER of 1 would mean that each recommended workup resulted in a diagnosis of lung cancer. An optimum ER has not been established for lung cancer, but it has been suggested that for lung surgery, a rate of 10% for non-malignant resections is desirable (9), this would be an ER of 1.1. In breast cancer biopsies which have a much lower risk than lung biopsies, it is recommended that 40% of biopsies should be negative to ensure sufficient workup to diagnose breast cancers early enough this would represent an ER of 1.4

      Results

      Table 1 provides the frequency of following the recommendations, the number of cancers diagnosed and the ER for each protocol. In summary, I-ELCAP recommendations had the lowest ER values for overall, immediate and delayed workup, and for potential biopsies.

      Discussion

      All three protocols used LDCT to guide evaluation of NCNs, particularly for the smaller NCNs. LDCT is a very low risk test as it requires no injection of contrast, the radiation dose is deemed “small” and “hypothetical” by the American Association of Physicists in Medicine [10], and the charge for a LDCT is 10-20 times lower than for a PET scan. This underscores the recognition that LDCT is a very useful tool for identifying growth at a malignant rate prior to further invasive testing.

      The main point is that the definition of a “positive result” needs to be continually reevaluated and updated in light of emerging technology and evidence from ongoing screening programs with the goal of reducing unnecessary invasive procedures for non-malignant pulmonary NCNs, which will markedly reduce the concerns about potential harms and increase the benefit by early diagnosis and treatment of small, early curable lung cancers.

      References

      1. Henschke CI, Salvatore M, Cham M, Powell CA, DiFabrizio L, Flores R, et al. Baseline and annual repeat rounds of screening: implications for optimal regimens of screening. Eur Radiol. 2018; 28:1085-1094.

      2. Henschke CI, Yip R, Ma T, Aguayo SM, Zulueta J, Yankelevitz DF, for the I-ELCAP Investigators. CT screening for lung cancer: comparison of three baseline screening protocols. Eur Radiol 2018; 29:3321-3322.

      3. International Early Lung Cancer Action Program protocol. (2016) www.IELCAP.org/sites/default/files/I-ELCAP-protocol.pdf Accessed June 27, 2019

      4. American College of Radiology (ACR). Lung CT screening reporting & data system (Lung-RADS Version 1.0). https://www.acr.org/Quality-Safety/Resources/LungRADS

      5. Oudkerk M, Devaraj A, Vliegenthart R, Henzler T, Prosch H, Heussel CP, et al. European position statement on lung cancer screening. Lancet Oncology 2017; 18: e754-e766.

      6. Henschke CI, Yip R, Wolf A, Flores R, Liang M, Salvatore M, et al. CT screening for lung cancer: part-solid nodules in baseline and annual repeat rounds. AJR Am J Roentgenol 2016; 11:1-9.

      7. Radiologic Society of North America Quantitative Imaging Biomarkers Alliance (QIBA) Calculator. (2017) http://accumetra.com/solutions/qiba-lung-nodule-calculator. Accessed May 1, 2018.

      8. Li K, Yip R, Avila R, Henschke CI, Yankelevitz DF. Size and growth assessment of pulmonary nodules: consequence of the rounding. J Thorac Oncol 2016; 12: 657-62.

      9. Flores R, Bauer T, Aye R, et al. Balancing curability and unnecessary surgery in the context of computed tomography screening for lung cancer. J Thorac Cardiovasc Surg. 2014; 147:1619-26.

      10. American Association of Physicists in Medicine. AAPM Position Statement on Radiation Risks from Medical Imaging Procedures. https://www.aapm.org/org/policies/details.asp?id=406&type=PP Accessed June 27, 2019

      ch_management protocol-table.png

      Only Members that have purchased this event or have registered via an access code will be able to view this content. To view this presentation, please login, select "Add to Cart" and proceed to checkout. If you would like to become a member of IASLC, please click here.

      Only Active Members that have purchased this event or have registered via an access code will be able to view this content. To view this presentation, please login or select "Add to Cart" and proceed to checkout.

  • +

    P1.11 - Screening and Early Detection (ID 177)

    • Event: WCLC 2019
    • Type: Poster Viewing in the Exhibit Hall
    • Track: Screening and Early Detection
    • Presentations: 2
    • Moderators:
    • Coordinates: 9/08/2019, 09:45 - 18:00, Exhibit Hall
    • +

      P1.11-22 - Lung Cancer Growth: Impact of Different Assumptions (ID 2522)

      09:45 - 18:00  |  Author(s): Rowena Yip

      • Abstract

      Background

      The purpose of this study is to determine which of two models, exponential or linear best approximates growth of lung cancer so as to predict when follow up CT exams should be obtained when a nodule is found.

      Method

      We reviewed our database of documented lung biopsies and identified those cases where the diagnosis of lung cancer in a solid nodule was confirmed and there were a total of three scans. Volume doubling times (VDTs) were calculated based on the first two scans using either the exponential method or the radial method and the third time point was used to determine which model best fit the actual result. We also allowed for measurement error to be considered based on the QIBA small nodule profile.

      Result

      We identified 100 cases that met the inclusion criteria. All were adenocarcinomas. On the first scan, the median nodule size was 8.2mm [Interquartile range(IQR):6.0-11.8)]. The median time between scans was 133.5 days (IQR:77.5-202 days) for the first and second scans, 75 days (IQR: 31.5-186.0 days) between second and third scans and 242.0 days (IQR: 131.5-424.0 days) between first and third scans. Median VDT from the first two scans was 139.0 days (IQR: 73.8-365.1 days). Using the calculated VDT from the first two scans, we found that 94 of the 100 cases had the third scan within 3 VDTs as estimated from the two scans. For these 94 cases, when accounting for the QIBA error measurements, both the linear or exponential models are plausible. For the 6 cases where the time interval between the second and third scan was longer, the exponential model provided a better fit for two, the linear model was better for two, and for the remaining two cases, it was not clear which model provided the better fit.

      Conclusion

      When considering the short time intervals typically used in obtaining follow-up CT scans for small pulmonary nodules, we found that it had minimal impact in predicting the ultimate size of the nodule as measurement error could account for results using either method. It was only after at least 3 doubling times that the potential impact of choice of method becomes apparent as with the exponential method the doubling time remains constant while with the radial method the doubling time increases with increasing size and therefore overall growth substantially decreases with longer time interval.There remains uncertainty in terms of how nodules grow, whether it is only along the advancing edge or by all cells doubling. This has little impact clinically in terms of short term follow up. However, when considering situations where there may be long delays between CT scans such as moving the interval for screening from 1 year to 2 years, it has a very large impact.

    • +

      P1.11-28 - Lung Cancer: Susceptibility and Survival Differences for Women and Men (ID 2416)

      09:45 - 18:00  |  Author(s): Rowena Yip

      • Abstract

      Background

      To determine the lung cancer susceptibility to tobacco carcinogens and survival after diagnosis of lung cancer for women and men in the International Early Lung Cancer Program (I-ELCAP).

      Method

      We used the prospective I-ELCAP cohort of asymptomatic men and women to identify all who were 40 years and older, had smoked at least 5 pack-years, and had low-dose CT screening in I-ELCAP between 1992 and 2018 at participating institutions in two continents, North America or Europe. Logistic regression models were used to calculate the odds ratio (OR) for lung cancer in women compared to men, adjusting for age, smoking history, and location. To account for time from baseline to lung cancer diagnosis, hazard ratio (HR) using Cox proportional hazards models were calculated for lung-cancer-specific mortality in women and men, conditioned on age, smoking history, disease stage, histology, whether resection was performed, and continent (NA or Europe). Interaction between sex and location was also evaluated.

      Result

      Of the 23,438 women, 18,451 were in North America, 4987 in Europe. Of the 31,365 men, 18,451 in North America, 22,812 in Europe. Lung cancer was diagnosed in 475 women and 509 men; in NA, frequency was significantly higher in women (2.2% vs. 1.5%, p<0.0001) while in Europe, it was significantly lower (1.4% vs. 2.0%, p =0.007). As the interaction between sex and continent was significant (p<0.0001), separate multiple logistic regression analyses were performed which showed sex to be a significant independent predictor of lung cancer in North America (ORwomen=1.7, 95% CI:1.4-2.0), but not in Europe (ORwomen=0.8, 95% CI: 0.6-1.1).

      Median follow-up time of the 742 and 242 lung cancer patients in North America and Europe was 89.8 months and 67.0 months, respectively. Lung cancer deaths occurred less frequently in women than in men in North America [NA: 47/406 (11.6%) vs. 59/336 (17.6%)] and in Europe [3/69 (4.4%) vs. 17/173 (9.8%)]. In North America, the risk of death was significantly lower for women (unadjusted HRwomen = 0.6, 95% CI: 0.4-0.9), but no longer significant when adjusted for other covariates. In Europe, unadjusted HRwomen = 0.44 (95% CI: 0.13-1.50) was not significant.

      Conclusion

      Women appear to have an increased susceptibility to tobacco carcinogens in NA but not in Europe. In both continents, however, rates of fatal outcome from lung cancer were slightly, but not significantly lower for women.

  • +

    P1.13 - Staging (ID 181)

    • Event: WCLC 2019
    • Type: Poster Viewing in the Exhibit Hall
    • Track: Staging
    • Presentations: 1
    • Moderators:
    • Coordinates: 9/08/2019, 09:45 - 18:00, Exhibit Hall
    • +

      P1.13-01 - The Importance of Staging of Lung Cancers, 30 mm or Less, Separately for Subsolid and Solid Nodules (ID 1413)

      09:45 - 18:00  |  Presenting Author(s): Rowena Yip

      • Abstract

      Background

      To determine pathologic results on non-small-cell lung cancers (NSCLCs), 30 mm or less in maximum diameter, separately by tumor consistency (solid, subsolid) on CT scans as we had shown that long-term survival was significantly different by tumor consistency and by type of parenchymal invasion.

      Method

      We reviewed all patients enrolled in the Initiative for Early Lung Cancer Research on Treatment (IELCART), a prospective cohort study of patients with first primary T1a-T1c NSCLC between 2016 and 2018 who had surgical resection. Short-axis diameter of N1-N3 lymph node on CT and SUVmax uptake on FDG-PET, if performed, were documented with values ≥ 2.5 defined as PET positive. Pathology reports were reviewed for N1-N3 lymph nodes (LNs) metastases and parenchymal invasion.

      Result

      table.pngAmong 347 patients, 280 (80.7%) and 67 (19.3%) had solid and subsolid NSCLCs, respectively; all subsolid NSCLCs were adenocarcinoma. There was FDG-PET uptake in 253 (93.3%) with solid NSCLCs and in 55 (91.7%) with subsolid NSCLCs.

      None of the 67 subsolid NSCLCs had N1 or N2 LN metastases (Table 1). Among the 280 solid NSCLCs, none of the 42 NSCLCs≤ 10 mm had N1 or N2 metastases, while 5 of the 238 solid NSCLCs greater than 10 mm had N2 and 14 had N1 LN metastases. None of the N2 LNs were positive on FDG-PET and only 4(28.6%) of the 14 N1 LNs were positive on FDG-PET.

      Angiolymphatic invasion was most frequently, followed by pleural and major vascular invasion (Table 1). For solid NSCLCs, invasion increased with increasing tumor diameter.

      Conclusion

      No N1-N3 LN metastases were identified in solid NSCLCs ≤ 10 mm; none in subsolid NSCLCs ≤ 30 mm. None with N2 LN metastases were positive on FDG-PET. This suggests that for NSCLCs, 30 mm or less, clinical staging be based on solely tumor size. For pathologic staging, we recommend differentiating staging classification by tumor consistency in line with the latest recommendations for pathologic assessment.

  • +

    P2.11 - Screening and Early Detection (ID 178)

    • Event: WCLC 2019
    • Type: Poster Viewing in the Exhibit Hall
    • Track: Screening and Early Detection
    • Presentations: 2
    • Moderators:
    • Coordinates: 9/09/2019, 10:15 - 18:15, Exhibit Hall
    • +

      P2.11-08 - CT Screening of Never Smokers (ID 1411)

      10:15 - 18:15  |  Author(s): Rowena Yip

      • Abstract

      Background

      We wanted to update our previous reports of the impact of SHTS on lung cancer and cardiovascular disease in never smokers and the usefulness of low-dose CT (LDCT) screening using the I-ELCAP protocol.

      Method

      Never smokers, defined as having smoked less than 100 cigarettes in their lifetime, were enrolled in our LDCT screening program. All signed IRB-HIPAA compliant consents. Patient demographics, medical history, and validated SHTS-exposure questionnaire were obtained at baseline. The SHTS-exposure score was computed for all participants together with LDCT Ordinal score for coronary artery calcifications (CAC), emphysema, lung cancer diagnosis and treatment were documented. At two of the institutions, we also performed pulmonary function tests, and measured the main pulmonary artery(MPA) and ascending aorta(AA) measurements, determined the automated aortic calcium score and extent of atherosclerotic plaque present in the coronary arteries using CT angiograms. Frequency of abnormal pulmonary function (FEV1/FVC ratio<0.7) and MPA/AA ratio≥1.0 were evaluated. We examined the relationship between SHTS exposure and these disease conditions.

      Result

      Among 14,018 never smokers, 6733 (48.1%) were women, 7276 (51.9%) men. Among them, 5236 (37.4%) had at least one noncalcified nodules (NCNs). Of the 14,018, 855 (6.1%) had at least one NCN 6.0 mm but less than 15.0 mm for which follow-up LDCT is recommended and 113 (0.8%) had NCN 15.0 mm or larger (Table 1).

      Lung cancer was diagnosed in 55 (0.4%); 53(96.4%) resulting from findings on baseline LDCT and 2(3.6%) from the subsequent annual repeat LDCTs. Of the 55, 47 (85.5%) were clinical stage I; 49 had surgical resection, 4 treated with radiation therapy, and 2 with chemotherapy. Diagnosis was adenocarcinoma in 44, squamous-cell in 7, small-cell in 1 and other in 3. Post-surgically, 45 (81.8%) of the 47 were pathologic Stage IA (T1a-1cN0M0).

      Of the 14,018 never smokers, the CAC score was 0 for 10,956 (78.2%), 1-3 for 1941 (13.9%), and 4-12 for 1211(8.0%). Emphysema was present in 310 (2.2%) participants.

      The prevalence of lung cancer (p=0.04) was significantly associated with SHTS exposure, as was CAC (p<0.0001) and emphysema (p=0.03). In the subset of participants where additional measurements are available, abnormal pulmonary function tests (p=0.04), automated aortic calcium score (p=0.009), MPA/AA ratio≥1.0 (p=0.009) and presence and extent of coronary artery plaque (p<0.0001).

      Conclusion

      These results suggest that LDCT screening is of benefit for never smokers exposed to SHTS for identification of early lung cancer, cardiovascular disease and emphysema.

    • +

      P2.11-23 - Performance of Lung Cancer Risk Prediction Models in I-ELCAP Smokers (ID 1389)

      10:15 - 18:15  |  Presenting Author(s): Rowena Yip

      • Abstract

      Background

      To determine the performance of lung cancer risk prediction models in predicting lung cancer in smokers enrolled in the International Early Lung Cancer Program (I-ELCAP).

      Method

      62,071 asymptomatic ever-smokers enrolled into the international multi-institutions I-ELCAP for low-dose CT screening between 1993-2018. Demographics, smoking history, comorbidities, exposures and family history of lung cancer were collected at time of baseline CT scan. All participants received a baseline screening scan and subsequently annual repeat CT scans, and they were prospectively followed for the diagnosis of lung cancer. Diagnosis and treatment of lung cancer were verified and documented in the ELCAP Management System. To compare the predicted risk of lung cancer, we applied four lung cancer risk models: the Bach Model, the Liverpool Lung Project Incidence (LLPi) Risk model, the Prostate, Lung, Colorectal, and Ovarian Cancer Screening Trial Model 2012 (PLCOM2012), and the Pittsburgh Predictor Model to the I-ELCAP cohort. Model calibration and discrimination were assessed using expected-to-observed (E/O) ratio and the area under the curve (AUC) statistics. E/O ratio >1 indicates that the model predicts more lung cancer cases than observed.

      Result

      PLCOM2012 model was the most predictive of lung cancer for ever-smokers in I-ELCAP with the AUC 0.61 being the highest, followed by Bach model (AUC 0.58), LLPi model (AUC 0.57) and Pittsburgh Predictor (AUC 0.52). E/O ratios suggested that the PLCOM2012 model, Bach model, LLPi model and Pittsburgh Predictor model tends to overestimate the number of lung cancers. The LLPi model overestimated as many as 4 times more lung cancer cases.

      iaslc risk models figure.png

      Conclusion

      Using data from I-ELCAP, the four existing lung cancer risk prediction models have AUCs ranged between 0.52-0.61, PLCOM2012 model was the top performer out of the four models.

  • +

    P2.16 - Treatment in the Real World - Support, Survivorship, Systems Research (ID 187)

    • Event: WCLC 2019
    • Type: Poster Viewing in the Exhibit Hall
    • Track: Treatment in the Real World - Support, Survivorship, Systems Research
    • Presentations: 1
    • Moderators:
    • Coordinates: 9/09/2019, 10:15 - 18:15, Exhibit Hall
    • +

      P2.16-03 - IELCART Quality of Life in the First Year After Surgery for Stage IA Lung Cancer Patients: Preliminary Results (ID 1409)

      10:15 - 18:15  |  Author(s): Rowena Yip

      • Abstract

      Background

      To compare quality of life (QoL) after lobectomy (L) and sublobar resection (SLR) within the first postoperative year among patients undergoing video-assisted thoracoscopic surgery.

      Method

      We used a prospective cohort of Stage I lung cancer patients from the Initiative for Early Lung Cancer Research on Treatment (IELCART). QoL used three validated instruments: SF-12 physical (PCS) and mental health (MCS), FACT-L lung cancer symptoms, and PHQ-4 for anxiety and depression. The QoL scores were measured before surgery, and within 4, 6, and 12 months after surgery. For each QoL measure, a piece-wise linear mixed effects model was used to estimate changes in average scores and test for differences between L and SLR patients within 2 months post-surgery and from 2 to 12 months. Social support was also assessed at baseline using the MOS survey.

      Result

      Of the 160 patients, 58 (36.3%) had L and 102 (63.7%) SLR. After adjustment for demographics, BMI, pack-years of smoking, and comorbidities, mean QoL and social support scores at baseline did not differ between L and SLR patients. The post-operative rates of change are given in Table 1. L showed significant decreases in PCS (p = .01) and anxiety scores (p = .0001) within 2 months post-surgery and significant improvement from 2 to 12 months in PCS (p = .005) and FACT-L QoL scores (p = .01). SLR anxiety scores decreased (p = .004) within the first two months post-surgery; PCS did not change significantly within the first two months but improved significantly (p = .02) from 2 to 12 months. Other measures were stable across the year after surgery. No significant differences between L and SLR were detected in the post-operative rates of change.

      table 1.png

      Conclusion

      Mental health, anxiety, and depression scores either improved or remained stable. Decreases in physical health persisted 2 months postoperatively, but thereafter improved significantly. Implications for intervention include provision of preoperative counseling about anticipated changes in physical function after surgery, and post-op interventions aimed at improving physical function.