[800] Necrotizing Vasculitis Involving the Prostate or Periprostatic Tissue: An Analysis of 12 Cases

M Latour, N Rekhtman, JI Epstein. Johns Hopkins Hospital, Baltimore; MSKCC, New York; CHUM, Montreal, Canada

Background: Vasculitis involving the prostate and periprostatic tissue has been described in the literature but still remains a rare finding. It can occur in patients with systemic vasculitis (Wegener's granulomatosis, Polyarteritis nodosa, and Giant cell arteritis) or as a localized process. Isolated forms include infectious vasculitis, localized small-vessel vasculitis, localized giant-cell arteritis, lymphocytic vasculitis of the prostate tranzition zone, and polyarteritis nodosa-like vasculitis.
Design: A search of the surgical pathology files at our institution from 1992 to 2008 revealed 12 cases of necrotizing vasculitis involving the prostate or the seminal vesicle. 6 were found on a radical prostatectomy and 6 were found on a needle core biopsy. Histological findings were recorded and clinical data were collected for each case.
Results: Patients ranged in age from 48 to 76 years (mean of 62). 8 patients (67%) had prostatic adenocarcinoma concurrently to vasculitis. Of them, 4 had Gleason score 6, 3 had Gleason score 7, and one had Gleason score 9. PSA levels were available for 7 patients (6 with adenocarcinoma) and ranged from 1.6 to 40 ng/ml. All cases had fibrinoid necrosis. Transmural inflammation was granulomatous in 2, purely lymphocytic in 2, lymphoplasmacytic in 1, and composed of a variable mixture of neutrophils, lymphocytes, plasma cells, and histiocytes in 7. Eosinophils were predominant in 2 cases. Vasculitis involved small vessels in 4 cases (33%), small to medium vessels in 5 cases (42%), and medium vessels in 3 cases (25%). Tissue involvment was focal in 9 cases (75%) and multifocal in 3 cases (25%). The location of the vasculitis was intraprostatic in 7 cases (58%), periprostatic in 3 cases (25%), periseminal vesicle in 1, and both intraprostatic and periprostatic in 1. Clinical follow-up was available for 10 patients. No evidence of a systemic vasculitis was seen in 6 patients (mean follow-up of 52 months). Systemic disease was observed in 4 patients (33%) including a systemic granulomatous disease of unknown etiology, Rickettisia infection, monoclonal IgG paraproteinemia, and Hodgkin lymphoma.
Conclusions: Although rare, prostatic and periprostatic vasculitis may be the first manifestation of a systemic disease. However, isolated forms confined to the prostate have been described and are more frequent than previously thought.They can be a component of a paraneoplastic syndrome and may represent vascular changes secondary to a localized immune response.
Category: Genitourinary (including renal tumors)

Tuesday, March 10, 2009 1:00 PM

Poster Session IV # 124, Tuesday Afternoon