[807] Urothelial Carcinoma with Divergent Villoglandular Differentiation: A Study of 14 Cases

M Lim, NV Adsay, DJ Grignon, AO Osunkoya. Emory University School of Medicine, Atlanta, GA; Indiana University School of Medicine, Indianapolis, IN

Background: Tumors of the urinary bladder may have a variety of histologic patterns. Tumors with either glandular or villous features, such as villous adenomas, in situ adenocarcinomas, invasive adenocarcinomas, and variants of urothelial carcinoma (UC) such as micropapillary carcinomas have been described. However, UC with both villous and glandular features have not been well characterized.
Design: We identified 14 cases of UC with divergent villoglandular differentiation (UCDVD). These cases were defined as having villoglandular features if they contained superficial finger-like processes lined by epithelium having true glandular lumina. The cases were evaluated for the following features; presence of non-invasive and invasive UC, variants of UC, adenocarcinoma component, cystitis cystica et glandularis, depth of invasion and angiolymphatic invasion.
Results: Mean patient age at presentation was 70 years (range 46 -84 years) with a male predominance (5:1). 5 cases (36%) had lamina propria invasion, 5 cases (36%) had muscularis propria invasion and 1 case (7%) had extravesicular extension. A concurrent high grade papillary UC component was identified in 11 cases (79%), superficial micropapillary component in 5 cases (36%), in-situ UC component in 3 cases (21%), plasmacytoid component in 3 cases (21%), invasive adenocarcinoma in 2 cases, sarcomatoid carcinoma component in one case (14%) and small cell carcinoma component in 1 case (7%). Cystitis glandularis was present in 3 cases (21%). Angiolymphatic invasion was identified in 3 cases (21%). Histologically, the villoglandular components were composed of finger-like processes lined by glands intimately admixed with high grade UC. Many of the glands had cribriform features lined by non-mucin producing cuboidal to columnar cells. However, the size and shape of the glands were variable, with some being small and slit-like and others being large and adenoma-like. In one case, the glands were lined by goblet cells. Variable quantities of intraluminal necrosis, apoptotic bodies and eosinophilic secretions were present in all cases. Luminal mucin was present in two cases.
Conclusions: UCDVD are high grade tumors typically seen in elderly males, characterized by superficial filliform processes lined by glands intimately admixed with high grade UC (in situ or invasive) and other aggressive variants of UC. These relatively rare tumors should be recognized as a divergent variant of UC.
Category: Genitourinary (including renal tumors)

Tuesday, March 10, 2009 9:30 AM

Poster Session III # 98, Tuesday Morning