1. Invasive plasmacytoid urothelial carcinoma: A comparative study of E-cadherin and P120 catenin
- Author
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Ankur R. Sangoi, L. Priya Kunju, Bradley A. Stohr, and Emily Chan
- Subjects
Male ,0301 basic medicine ,Delta Catenin ,Pathology ,medicine.medical_specialty ,Concordance ,Pathology and Forensic Medicine ,CDH1 ,03 medical and health sciences ,0302 clinical medicine ,Antigens, CD ,Biomarkers, Tumor ,medicine ,Carcinoma ,Humans ,Aged ,Aged, 80 and over ,Carcinoma, Transitional Cell ,biology ,Cadherin ,business.industry ,Catenins ,Histology ,Middle Aged ,Cadherins ,medicine.disease ,Staining ,030104 developmental biology ,Urinary Bladder Neoplasms ,030220 oncology & carcinogenesis ,biology.protein ,Immunohistochemistry ,Female ,business ,Lobular Neoplasia - Abstract
Summary Invasive plasmacytoid urothelial carcinomas (PUCs) are an uncommon aggressive variant, which often shows immunohistochemical loss of E-cadherin, underlying its distinct discohesive histology. The marker P120 (well described in breast pathology as being a diagnostic tool alongside E-cadherin for lobular neoplasia) has not been evaluated in PUCs. Biopsies, transurethral resections, and cystectomies of PUCs were collected, and whole-slide immunohistochemical analysis of E-cadherin and P120 was applied. A subset of cases were also tested for CDH1 mutation. PUC cases were stratified into morphologic categories of classic, pleomorphic, or desmoplastic. For E-cadherin, 24 of 33 (73%) cases showed an abnormal staining pattern, consisting of complete absence of staining (17/24; 71%) or cytoplasmic staining (7/24; 29%). For P120, 24 of 33 (73%) cases showed an abnormal staining pattern, consisting of loss of membranous staining with cytoplasmic reactivity. Only 2 cases showed a discordant E-cadherin/P120 immunoprofile (94% concordance). Significant staining differences among the 3 morphologic categories were not found. CDH1 mutation was found in 4 of 8 (50%) of cases, with 3 of 4 (75%) cases showing matched molecular/immunoprofile reactivity. No cases with CDH1 mutation showed discordant pattern E-cadherin/P120 immunoreactivity. Our rate of aberrant E-cadherin immunoreactivity in PUCs (73%) is similar to a meta-analysis of published cases (74%). We also report an identical rate of aberrant P120 immunoreactivity in PUCs (73%). While PUC remains a histologic diagnosis, in a subset of cases showing a less appreciated pattern (such as desmoplastic) or confounding cytoplasmic E-cadherin reactivity, the utility of paired P120 staining may be a useful diagnostic tool.
- Published
- 2020