Histoplasmosis Associated With Bat Guano Exposure in Cannabis Growers: 2 Cases.

is a pathogenic dimorphic fungus with evolving epidemiology. Initially described as endemic to the Ohio and Mississippi river valleys, the infection now regularly occurs in central and eastern United States, with cases reported across the entire country. Transmission happens via inhalation of conidia during activities that disturb fungal hyphae.

TRPS1 is a useful marker in differentiating metastatic breast carcinoma from pancreatic adenocarcinoma in fine-needle aspiration specimens.

Objectives: Distinction of metastatic breast carcinoma (BC) to the pancreas from primary pancreatic adenocarcinoma (PAC) is essential but challenging. Breast carcinoma shares similar morphology and exhibits an overlapping immunohistochemistry (IHC) profile with PAC. We investigated the utility of recently reported trichorhinophalangeal syndrome type 1 (TRPS1) IHC in differentiating metastatic BC from PAC in fine-needle aspiration (FNA) specimens.

SATB2 is an Emergent Biomarker of Anaplastic Thyroid Carcinoma: A Series with Comprehensive Biomarker and Molecular Studies.

Anaplastic thyroid carcinoma (ATC) is a rare and aggressive thyroid malignancy typically comprised of undifferentiated tumor cells with various histologic morphologies, which makes the diagnosis challenging. These tumors commonly show loss of thyroglobulin and TTF1 with preservation of cytokeratin (67%) and Paired Box Gene 8 (PAX8) (55%) expression. Identification of a sensitive immunohistochemical stain to aid in the diagnosis of ATC would be beneficial.

Sebaceous Carcinoma of the Middle Ear: A Case Report.

Here we present the first case of sebaceous carcinoma of the middle ear. We discuss the treatment course and post treatment results after 11 years of follow up. We further summarize the available literature of sebaceous carcinoma of the temporal bone, which prior to this case was exclusively limited to the external auditory canal.

Validation and interpretation of Pan-TRK immunohistochemistry: a practical approach and challenges with interpretation.

Objectives: Actionable, solid tumor activating neurotrophic receptor tyrosine kinase (NTRK) fusions are best detected via nucleic acid-based assays, while Pan-TRK immunohistochemistry (IHC) serves as a reasonable screening modality. We describe a practical and cost-effective approach to validate pan-TRK and discuss challenges that may be encountered.

Methods: Pan-TRK Clone EPR17341 was validated in accordance with the 2014 consensus statements set forth by the College of American Pathologists.