[705] Carcinoma of Collecting Ducts of Bellini: Analysis of 27 Distinctive Cases of Renal Cell Carcinoma with Aggressive Clinical Behavior

MB Amin, R Gupta, AO Osunkoya, O Hes, A Billis, CE Bacchi, D Hansel, M Zhou, MG deCastro, H Moch, P Salles, RA Cabrera, AM Gown. Cedars Sinai Medical Center, LA, CA; Emory University Hospitals, Atlants; Charles University Hospital, Pilsen, Czech Republic; State University of Campinas, Campinas, Brazil; Cunsultoria em Patalogia, Sao Paulo, Brazil; Cleveland Clinic Foundation, Cleveland; Santa Casa School of Medicine, Sao Paulo, Brazil; University Hospital Zurich, Zurich, Switzerland; Associao Mario Penna-Hospital, Belo-Horizonte, Brazil; Institute of Oncology, Lisbon, Portugal; PhenoPath, Seattle

Background: Although first described in 1949 and formally recognized by the W.H.O., large series describing the detailed morphologic spectrum of these rare neoplasms is lacking.
Design: We performed a detailed clinicopathologic analysis of 27 cases; cases of renal medullary carcinoma were excluded.
Results: The age ranged from 6-87 yrs (mean 46) with marked male preponderance (4:1). The tumors primarily occurred in the medullary region with or without cortical involvement and measured 4-12 cm (mean 8). 96% of tumors extended into perinephric fat or beyond Gerota's facia. Predominantly tubular, tubulopapillary or glandular architecture characterized the tumors with occasional solid sheets (13 cases), rhabdoid morphology (4 cases) and sarcomatoid change (3 cases) . Characteristic features included a myxoid (57%), fibrotic (23%) or fibrosclerotic (20%) desmoplastic stroma and predominantly lymphocytic inflammation. The tumor cells were invariably high grade (Fuhrman nuclear grade 3) with moderate to abundant eosinophilic cytoplasm; hobnailing was present in 50% of cases. Intraluminal mucin was seen in 46% of cases; it was predominantly patchy though prominent in 11%. Geographic necrosis was seen in 60%. The immunohistochemical profile was CK7 positive (30%), CK20 negative, high molecular keratin weight positive (18%) and PAX-2 positive (6%). 50% of patients presented with metastasis; 91% of the patients died of disease (12 months median follow up). The median survival was 11 months. Metastatic sites included hilar lymph nodes, lung, bone and liver.
Conclusions: Collecting duct carcinoma is an extremely aggressive clinicopathologic subtype of renal cell carcinoma with proclivity to occur in younger males and presentation with metastatic disease. Accurate characterization is necessary for appropriate triaging of patients into ongoing clinical trials with specific therapeutic protocols.
Category: Genitourinary (including renal tumors)

Wednesday, March 11, 2009 1:00 PM

Poster Session VI # 131, Wednesday Afternoon