Virtual Library

Start Your Search

Sanja Dacic



Author of

  • +

    MTE02 - Update on WHO Classification and Staging of Lung Cancer (Ticketed Session) (ID 812)

    • Event: WCLC 2018
    • Type: Meet the Expert Session
    • Track: Pathology
    • Presentations: 1
    • Now Available
    • Moderators:
    • Coordinates: 9/24/2018, 07:00 - 08:00, Room 203 BD
    • +

      MTE02.01 - Update on WHO Classification and Staging of Lung Cancer (Now Available) (ID 11548)

      07:00 - 07:30  |  Presenting Author(s): Sanja Dacic

      • Abstract
      • Presentation
      • Slides

      Abstract

      The most significant changes in the 2015 WHO classification of the lung tumors include classification criteria for small biopsy and cytology specimens, use of immunohistochemistry, integration of molecular testing, adoption of the IASLC/ATS/ERS adenocarcinoma classification and a strict definition of large cell carcinoma limited to surgical resection specimens only. 1,2 Tumors that show unequivocal morphology of adenocarcinoma or squamous cell carcinoma on a small specimen should be diagnosed without immunohistochemistry. Immunohistochemical work up of poorly differentiated tumors should be limited to TTF-1and p40/p63, while neuroendocrine markers should be used only if morphologically indicated. This approach should reduce the diagnosis of NSCC, NOS to less than 5 % and preserve tissue for molecular testing. 1,2

      Major changes in the adenocarcinoma classification for resected specimens include addition of adenocarcinoma in situ (AIS) to preinvasive group that already includes atypical adenomatous hyperplasia. Minimally invasive adenocarcinoma (MIA) defined as a solitary, lepidic predominant adenocarcinoma presenting measuring in gross size 3 cm or less and with invasion of ≤
5 mm was added as a new category. These tumors are also recognized by the 8th edition of the AJCC staging of lung cancer and include Tis(adenocarcinoma) and T1a-mi. T stage of non-mucinous lepidic predominant adenocarcinomas is based on the microscopic size of invasion, but gross size should be recorded in the pathology reports. Multifocal ground glass opacities/lung nodules most frequently present as MIAs and should be classified by the T category of the lesion with the highest T along with the number of lesions (#) or simply (m) for multiple indicated in parentheses, and with a single N and M category that applies to all of the multiple tumor foci. This approach should be applied to grossly or microscopically identified lesions occurring in the same or in different ipsilateral or contralateral lobes.3 For non-lepidic adenocarcinoma T stage is determined by gross size in 1.0 cm increments as each size subgroup carries prognostic significance.

      Former mucinous BAC are reclassified as invasive mucinous adenocarcinoma, excluding tumors that meet criteria for AIS or MIA. Signet ring and clear cell carcinomas are considered to represent cytologic variants rather than specific subtypes.

      Invasive adenocarcinomas should be subtyped by semi-quantitatively estimating the percentage of the various subtypes in 5% increments. 1,2 Reproducibility for lung adenocarcinoma predominant subtypes among pulmonary pathologists was good to moderate (κ-values 0.44 to 0.72).4 For untrained pathologists, κ-values were lower ranging from 0.38 to 0.47, but these improved after a training session and particularly for individual reviewer. 5

      The 2015 WHO classification defines large cell carcinomas based on morphology, as carcinomas without morphologic evidence of glandular, squamous or neuroendocrine differentiation, and also based on null immunophenotype and genotype. 1This change in definition reflect what was already happening in the pathology practice. According to National Cancer Institute (NCI) Surveillance Epidemiology and End Results registry the diagnosis of large cell carcinoma started to decline about the time that TTF-1 was introduced into clinical diagnosis. 6

      References:

      Travis WD, Brambilla E, Burke AP, Marx A, Nicholson AG. WHO Classification of Tumours of the Lung, Pleura, Thymus and Heart. Lyon: International Agency for Research on Cancer, 2015.

      
Travis WD. Et al. The 2015 World Health Organization Classification of Lung Tumors Impact of Genetic, Clinical and Radiologic Advances Since the 2004 Classification. J Thorac Oncol 2015; 10 (9); 1243-1260

      Frank C. Detterbeck, MD et al. The IASLC Lung Cancer Staging Project: Summary of Proposals for Revisions of the Classification of Lung Cancers with Multiple Pulmonary Sites of Involvement in the Forthcoming Eighth Edition of the TNM Classification . J Thorac Oncol 2016;11(5): 639-650

      Thunnissen E, Beasley MB, Borczuk AC, et al. Reproducibility of histopathological subtypes and invasion in pulmonary adenocarcinoma. An international interobserver study. Mod Pathol 2012;25:1574–1583. 


      Warth A, Cortis J, Fink L, et al.; Pulmonary Pathology Working Group of the German Society of Pathology. Training increases concordance in classifying pulmonary adenocarcinomas according to the novel IASLC/ ATS/ERS classification. Virchows Arch 2012;461:185–193. 


      Lewis DR, Check DP, Caporaso NE, Travis WD, Devesa SS. US lung cancer trends by histologic type. Cancer 2014;120:2883–2892. 


      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.

  • +

    OA03 - Advances in Lung Cancer Pathology (ID 897)

    • Event: WCLC 2018
    • Type: Oral Abstract Session
    • Track: Pathology
    • Presentations: 1
    • Now Available
    • Moderators:
    • Coordinates: 9/24/2018, 10:30 - 12:00, Room 205 BD
    • +

      OA03.03 - Phase 2B of Blueprint PD-L1 Immunohistochemistry Assay Comparability Study (Now Available) (ID 14530)

      10:50 - 11:00  |  Author(s): Sanja Dacic

      • Abstract
      • Presentation
      • Slides

      Background
      PD-L1 immunohistochemistry (IHC) has been established as companion or complementary diagnostic assays, each developed as predictive biomarker for specific anti PD1/PD-L1 immunotherapies. The Blueprint (BP) phase 1 comparability study demonstrated that three PD-L1 assays (28-8, 22C3, SP263) showed comparable analytical performance for assessment of PD-L1 expression on tumor cells (TPS), while the SP-142 PD-L1 assay appeared to stain a lower percentage of tumor cells when compared to the other assays. The first part of BP phase 2 (BP2A) re-affirmed these findings in a larger cohort of ‘real life’ specimens scored by 24 experienced pulmonary pathologists, and also showed that the 73-10 assay developed for avelumab showed greater sensitivity than all other assays to detect PD-L1 on tumour cells. BP2A also demonstrated generally excellent inter-observer agreement for tumor cell PD-L1 scoring using both glass slides and digital images, with slightly lesser agreement for the cytology samples included in the study cohort. Inter-observer agreement for immune cell scoring on glass or digital slides was poor. Phase 2B of Blueprint (BP2B) aimed to compare PD-L1 scoring on triplet samples representing large tumor resection blocks, small biopsy samples and fine needle aspirate cell blocks prepared from the same tumor. Method
      Triplet samples of large resected tumor block, small biopsy sample and fine needle aspirate cell block (the latter two taken from the resected tumour specimen) were gathered from 31 resected primary lung cancers (17 adenocarcinomas, 12 squamous cell carcinomas, and 2 large cell carcinomas). Sections from all 93 blocks were stained with the pharmDx 28-8 and 22C3, the FDA-approved SP142 and SP263, or clinical trial associated 73-10 PD-L1 assays, in a CLIA-approved immunohistochemistry laboratory. All H&E and PD-L1 IHC slides were scanned and digital images were used to score all cases by the same 24 pathologists involved in BP2A. As before, tumor cells PD-L1 staining were scored as continuous variable and into 7 cut-off-defined categories, as used in various immune checkpoint inhibitor trials. Immune cells were not scored. Result
      The data reaffirm the relative comparability of 28-8, 22C3 and SP263 assays across the range of scores; SP142 assay scores were lower, those for 73-10 higher. Inter-observer agreement between readers ranged from moderate to near perfect (Kappa-Fleiss (K-F) scores generally >0.7); best overall agreement was on aspirates. Overall, the agreement between scores on the different sample types from the same tumor was good (most K-F scores >0.7); aspirates showed no significant difference from biopsy samples or whole surgical blocks. In contrast to biopsies and surgical blocks, scores could, however, not be rendered in about 14% of aspirate sections. Conclusion
      The results of BP2B confirms earlier results and also demonstrate comparable performance for fine needle aspirates in those cases where TPS scores were possible.

      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.