Loss of BAP1 Protein Expression by Immunohistochemistry in the Salivary Duct Carcinoma Component of an Intracapsular Carcinoma ex Pleomorphic Adenoma of the Parotid Gland.

BACKGROUND: BRCA1-associated protein 1 (BAP1) is a tumor suppressor gene that is altered in a variety of neoplasms as well as in BAP1 tumor predisposition syndrome. BAP1 alterations are associated with aggressive behavior in some malignancies and may have treatment implications in future. We present the first documented case of loss of BAP1 protein expression by immunohistochemistry in the salivary duct carcinoma (SDC) component of an intracapsular carcinoma ex pleomorphic adenoma (CXPA) in the context of molecular loss of function of BAP1 in the neoplasm. METHODS: A woman of approximately 55 years of age presented with a deep parotid lobe mass, which was resected and found to be CXPA. BAP1 immunohistochemistry and next-generation sequencing was performed to further characterize the neoplasm. RESULTS: The neoplasm showed loss of BAP1 protein expression in the SDC component but retention in the residual pleomorphic adenoma (PA). Next-generation sequencing confirmed a BAP1 loss of function alteration in the neoplasm. CONCLUSION: This is the first documented case report of BAP1 protein expression loss in the SDC component of a CXPA. Future studies are needed to investigate the relevance of BAP1 alterations in SDC and CXPA, which may have prognostic and treatment implications.

Eccrine Porocarcinoma of the Vulva With Sarcomatoid Transformation, a New Human Papillomavirus-associated Malignancy? Case Report and Review of the Literature.

Eccrine porocarcinoma is a rare cutaneous neoplasm, and rarer still in the anogenital region. In the vulva, the most common carcinoma by far is squamous cell carcinoma; however, eccrine porocarcinoma can arise at this site. As the distinction between porocarcinoma and squamous cell carcinoma has important prognostic implications at other cutaneous sites, it stands to reason that it may have these same implications in the vulva. We present a case of an eccrine porocarcinoma in the vulva of a 70-year-old woman that, in addition, showed sarcomatoid transformation. This tumor harbored human papillomavirus-18 DNA and mRNA, raising the question of the role of the oncogenic virus in sweat gland neoplasms of the vulva.

The yield and impact of pulmonologist-performed EUS-B-FNA of subdiaphragmatic lesions-an institutional experience.

INTRODUCTION: Pulmonologists can biopsy structures below the diaphragm using the convex curvilinear ultrasound bronchoscope via the esophagus (EUS-B). The literature with respect to the value of EUS-B, rapid on-site evaluation, and final diagnostic yield for structures below the diaphragm is limited. We review our institutional experience. MATERIALS AND METHODS: Our database was queried retrospectively for EUS-B fine needle aspirations (FNAs) from 2013 to 2021. All procedures involving EUS-B-FNA of subdiaphragmatic structures were selected for analysis. The following data elements were collected for each patient: age, gender, clinical indication, sample site, on-site adequacy (OSA), preliminary and final diagnoses, and sufficiency of cell block for ancillary studies. RESULTS: A total of 75 subdiaphragmatic sites were biopsied in 74 patients. Of which, 87% of samples subjected to rapid on-site evaluation were deemed to contain adequate material (OSA+). There were no false-positive OSAs. Six cases remained nondiagnostic at the final diagnosis. The final diagnostic yield (with cell block) was 92% (69/75 cases). Cell block was sufficient for immunohistochemistry or special stains in all applicable cases (n = 36). Molecular testing was requested for 11 cases and successful in 10 (91%). Sampling of subdiaphragmatic sites changed the stage in 67% (38/57) of lung cancer patients. CONCLUSIONS: Pulmonologists can perform EUS-B-FNA of subdiaphragmatic sites with high OSA and final diagnostic yield when assisted by cytopathologists. Strong correlations exist between OSA, cell block adequacy, and subsequent capacity to perform ancillary testing. EUS-B below the diaphragm can make an important contribution to the diagnosis of lung cancer, nonpulmonary malignancies, and other diseases.

Intestinal T-cell lymphoma: A rare entity presenting with severe acute upper quadrant pain.

Primary gastrointestinal T-cell lymphomas are rare. Presenting symptoms can be non-specific, and imaging studies can show overlap with nonmalignant processes. Definitive diagnosis requires clinical suspicion and histologic evaluation with ancillary studies for appropriate disease classification and therapeutic intervention.