Reanalysis of the NCCN PD-L1 Companion Diagnostic Assay Study for Lung Cancer in the Context of PD-L1 Expression Findings in Triple-Negative Breast Cancer

The companion diagnostic test for checkpoint inhibitor immune therapy is an immunohistochemical test for PD-L1. The test has been shown to be reproducible for expression in tumor cells, but not in immune cells. Immune cells were used in the IMpassion130 trial which showed PD-L1 expression was associated with a better outcome. Two large studies have been done assessing immune cell PD-L1 expression in lung cancer. Here, we reanalyze one of those studies, to show that, even with an easier scoring method, there is still only poor agreement between assays and pathologist for immune cell PD-L1 expression

A Prospective Study of Loose Tissue Fragments in Non-Small Cell Lung Cancer Resection Specimens: An Alternative View to "Spread Through Air Spaces"

The World Health Organization Classification of Lung Tumors considers "Spread Through Air Spaces" a form of invasion in lung adenocarcinoma. The recently described spread of free-floating cell clusters during lung specimen sectioning, otherwise known as "Spread Through A Knife Surface," represents an ex vivo artifact. The purpose of this study was to prospectively investigate the presence and frequency of these free-floating tumor cell clusters in surgically resected lung cancer specimens and their possible relation to gross examination procedures. A prospective, multi-institutional study of non-small cell lung cancer resection specimen was undertaken. At prosection the first cut was made with a clean knife; the second cut was made in a parallel plane to the first. Four tissue blocks were taken from upper and lower parts of first and second cuts. Hematoxylin and eosin-stained slides were examined for displaced benign and/or malignant tissue fragments. Forty-four resection specimens were studied. The mean number of tumor clusters for blocks 1 to 4 was 0.36, 1.44, 1.86, and 1.95, respectively, and for benign fragments was 0.11, 0.11, 0.13, and 0.25, respectively. Almost all cell clusters were intra-alveolar. Comparison of tumor cell clusters in block 1 with blocks 2 to 4 was significant with P-values (Friedman test for repeated measures 0.03) 0.031, 0.02, and 0.05, respectively. Overall 93% of the loose tissue fragments could be explained by mechanical forces associated with tissue handling. While the 2015 World Health Organization Classification of Lung Tumors recognizes Spread Through Air Spaces as a form of lung cancer invasion, such is debatable and in many instances likely represents mechanical artifact, including dissemination along the prosecting knife blade

Pathologic findings of lung tumors diagnosed on baseline CT screening.

International audienceSixty-five people had a resection of their baseline screen-diagnosed lung cancers in the Early Lung Cancer Action Program. Forty-nine of the carcinomas were solitary, and 42 of these were adenocarcinomas. More than 1 carcinoma was found in 16 patients after pathologic examination of the lobectomy specimen; 15 of the 16 second carcinomas were adenocarcinomas, mixed subtype. Eighteen cases were submitted by local pathologists as Bronchioloalveolar carcinomas but were found to be invasive adenocarcinomas according to the World Health Organization classification by the Pathology Review Panel. Of the 65 resected cases, 57 were N0, 7 were N1, and 1 was N2. Upon careful review of the lobectomy specimens, 49 cases had solitary malignancies, 30 were Stage IA, 13 Stage IB, 3 Stage IIA, 2 Stage IIB, and 1 Stage IIIA on the basis of the American Joint Committee on Cancer/International Union for Cancer Control criteria. In the 16 cases found to have multiple malignancies, 6 had histologically different carcinomas and the remaining 10 had histologically identical malignancies. Eighty-three percent (76/92) of the carcinomas invaded the stroma with destruction of normal lung, and 21% (19/92) also showed either pleural or angiolymphatic invasion, even though 88% (57/65) of the carcinomas were free of lymph node metastases. This report describes the pathologic findings of the resected cases. Histopathologic distinctions among atypical adenomatous hyperplasia, bronchioloalveolar carcinomas, and invasive adenocarcinoma are described in detail

Novel MIR143HG::PLAG1 gene fusion identified in a rectal myxoid leiomyosarcoma

Myxoid leiomyosarcoma (MLS) is a rare but well-documented tumor that often portends a poor prognosis compared to the conventional leiomyosarcoma. This rare sarcoma has been reported in the uterus, external female genitalia, soft tissue, and other locations. However, a definite rectal MLS has not been reported. Recently five cases of MLS were reported to harbor PLAG1 fusions (TRPS1::PLAG1, RAD51B::PLAG1, and TRIM13::PLAG1). In this report, we present a case of rectal MLS with a novel MIR143HG::PLAG1 fusion detected by RNA next-generation sequencing

Comparison of pathologic findings of baseline and annual repeat cancers diagnosed on CT screening.

International audienceScreening for lung cancer produces two groups of lung cancers. Baseline cases include all prevalent cases with the expectation that slower-growing cancers and those that have achieved higher stage will be found in greater frequency. Repeat examination is expected to detect those cancers which have crossed the threshold for detection during the screening interval - 1 year in this study - and these are typically more rapidly growing cancers. The two groups encompass the full spectrum of lung cancers. Comparison of the baseline and annual repeat cases revealed differences in types of lung cancer. There were 202 baseline-detected cancers spanning the spectrum of pulmonary neoplasms with some slowly growing, some rapidly progressive and some at high stage; the 48 annual repeat cancers also included a spectrum of lung cancers but with more of the rapidly growing types, and more closely approximated the clinical spectrum of lung cancers. The NE carcinomas showed this trend best; small-cell carcinomas were under-represented and typical carcinoids were only found in the baseline group. Repeat cancers were found to grow rapidly, were typically smaller, less often multiple and the adenocarcinomas were less often pure BAC and less frequently contained a BAC component when invasive. The baseline adenocarcinomas included most of the BAC's, which is a diagnosis that requires special attention to its WHO definition. AAH was found to be frequently associated with adenocarcinoma, particularly BAC. Both baseline and annual repeat cases had a high percentage of invasive carcinomas with comparably high rates of resectability, high rates of node negativity and consequently a high proportion of cases in low stage