RESUMEN
Introduction. The identification of mitotic figures is essential for the diagnosis, grading, and classification of various different tumors. Despite its importance, there is a paucity of literature reporting the consistency in interpreting mitotic figures among pathologists. This study leverages publicly accessible datasets and social media to recruit an international group of pathologists to score an image database of more than 1000 mitotic figures collectively. Materials and Methods. Pathologists were instructed to randomly select a digital slide from The Cancer Genome Atlas (TCGA) datasets and annotate 10-20 mitotic figures within a 2â mm2 area. The first 1010 submitted mitotic figures were used to create an image dataset, with each figure transformed into an individual tile at 40x magnification. The dataset was redistributed to all pathologists to review and determine whether each tile constituted a mitotic figure. Results. Overall pathologists had a median agreement rate of 80.2% (range 42.0%-95.7%). Individual mitotic figure tiles had a median agreement rate of 87.1% and a fair inter-rater agreement across all tiles (kappa = 0.284). Mitotic figures in prometaphase had lower percentage agreement rates compared to other phases of mitosis. Conclusion. This dataset stands as the largest international consensus study for mitotic figures to date and can be utilized as a training set for future studies. The agreement range reflects a spectrum of criteria that pathologists use to decide what constitutes a mitotic figure, which may have potential implications in tumor diagnostics and clinical management.
RESUMEN
SMARCB1-deficient sinonasal carcinoma is a newly described entity, with less than 100 reported cases. It is characterized by basaloid or rhabdoid morphology and is diagnosed by complete loss of nuclear SMARCB1 (INI-1). The morphologic appearance, specific immunophenotypic markers, and unique molecular make-up distinguish this entity from other various malignant neoplasms. We present a case of a 55-year-old male that presented with a large progressing palatine mass. Magnetic resonance imaging showed a heterogeneous mass involving the left maxillary space. The initial biopsy was diagnosed as undifferentiated carcinoma. Resection was performed, and immunohistochemical studies revealed a complete loss of INI-1, refining the diagnosis to SMARCB1-deficient sinonasal carcinoma. Diagnosis of SMARCB1-deficient sinonasal carcinoma should be considered in all undifferentiated sinonasal carcinomas. Immunohistochemistry or molecular studies are mandatory to confirm the diagnosis and exclude other morphologically similar entities.
RESUMEN
OBJECTIVES: To determine the spectrum of various types of lymphoma in Bahrain according to the latest World Health Organization classification criteria. Methods: A retrospective review was conducted for all new lymphoma cases diagnosed at Salmaniya Medical Complex, Manama, Bahrain during the period from January 2010 to December 2015. Results: Two hundred and twenty-one new cases of lymphoma in Bahraini patients were diagnosed in the study period. Eighty patients had Hodgkin lymphoma, 140 had non-Hodgkin lymphoma, and one patient had composite lymphoma. In the Hodgkin lymphoma group, nodular sclerosis type was the most frequent type (48.75%), followed by mixed-cellularity type (27.5%), and nodular-lymphocyte predominant type (16.25%). In the non-Hodgkin lymphoma group, 124 (88.6%) cases were B-cell lymphomas, while the remaining were T-cell lymphomas. Diffuse large B-cell lymphoma was the most frequent type of non-Hodgkin B-cell type lymphoma (55.7%), followed by follicular lymphoma (10%). Conclusion: The distribution of lymphoma in Bahrain is similar to neighboring Middle East countries with a predominance of Hodgkin lymphoma and diffuse large B-cell lymphoma.
