Immunohistochemical Characterization of a Large Cohort of Triple Negative Breast Cancer.

Introduction. Triple negative breast carcinomas are characterized by a lack of hormone receptor and HER2 expression and inconsistent expression of breast-specific immunohistochemical markers. The expression of many site-specific markers in these tumors is largely unknown. The objective of the study was to examine the expression of widely used immunohistochemical markers on a large cohort of triple negative breast cancer. Methods. Sections from tissue microarrays were stained with 47 markers using routine protocols. Most markers were scored using a modified Allred method. ATRX, BAP1, SMAD4, e-cadherin, and beta-catenin were scored as retained or lost. Mammaglobin was considered positive if there was at least moderate intensity staining in any tumor cells. P16 was scored as overexpressed or not overexpressed; p53 was scored as wildtype, overexpressed, null, or cytoplasmic. Results. The cohort consisted of 639 tumors including 601 primary and 32 metastases. Overall, 96% expressed GATA3, mammaglobin, and/or SOX10 while 97% of no special type tumors expressed this panel. Carcinoma of apocrine differentiation demonstrated an AR positive, SOX10 negative, K5 negative/focal immunophenotype. PAX8 (SP348), WT1, Napsin A, and TTF1 (8G7G3/1) were never or rarely expressed while CA9, CDX2, NKX3.1, SATB2 (SATBA410), synaptophysin, and vimentin were variably expressed. Conclusions. Almost all TNBC express at least 1 of the 3 IHC markers: GATA3, mammaglobin, and/or SOX10. Carcinoma of apocrine differentiation is characterized by an AR positive, SOX10 negative, K5 negative or focal immunophenotype. Cautious interpretation of so-called site-specific markers, with knowledge of antibody clones, is required in excluding the diagnosis of triple negative breast cancer.

Squamous Cell Proliferation as a Reactive Mechanism to Laryngeal Cryptococcus Infection: A Case Report.

Cryptococcus neoformans (C. neoformans) is a ubiquitous encapsulated, obligate anaerobe, a dimorphic fungus that can be pathogenic in humans. C. neoformans infections arise primarily in immunocompromised individuals, such as human immunodeficiency virus (HIV) patients, as well as those who use inhaled corticosteroids regularly. Due to the wide variety of clinical findings associated with C. neoformans, infection within the head and neck is occasionally misdiagnosed as malignancy due to its protean manifestation. In this report, we describe the case of a C. neoformans infection resulting in an initial misdiagnosis due to an overlying laryngeal squamous cell proliferation mimicking laryngeal squamous cell carcinoma (SCC). This case is intended to provide further evidence for inhaled corticosteroid use predisposing patients to fungal infections, as well as to provide insight into the possible mechanism resulting in the initial diagnosis of malignancy. A review of recent literature is also discussed.