[927] Intratubular Granulomatous Reactions within Seminiferous Tubules: A Spectrum of Diseases

Sarah Karram, Chia-Sui Kao, Adeboye Osunkoya, Thomas M Ulbright, Jonathan I Epstein. Johns Hopkins Hospital, Baltimore, MD; Indiana University School of Medicine, Indianapolis, IN; Emory University School of Medicine, Atlanta, GA

Background: Idiopathic granulomatous orchitis (IGO) is a rare disease thought to result from an autoimmune reaction to spermatogenic elements. Its relationship to IgG4-related disease (IgG4-RD) has not been evaluated.
Design: 16 orchiectomy specimens (1984-2012) with a prominent intratubular granulomatous reaction were reviewed: IGO diagnosed in consultation at 2 institutions (n=6); intratubular germ cell neoplasia unclassified (IGCNU) with a granulomatous reaction and associated seminoma (GS, n=6); & miscellaneous granulomatous orchitis involving tubules (GO, n=4). Necrotizing GO without an intratubular component were controls (n=2).
Results: Men with IGO aged 32-86 yrs. presented with a mass suspicious for malignancy. 1 had a history of rheumatoid arthritis (RA), the rest had no history of inflammatory diseases. IGO results are summarized in Table.

% tubulesIgG4+/IgG+ (%)IgG4+/HPFIntratubular Inf.Intratubular MGCPT sclerosisInterstitial Inf.Interstitial fibrosis
100%>40%96 †1+L, 1+P, 1+AI1+1+3+L, 3+P0
100%>40%881+L, 1+P, ∗002+L, 2+P∗3+
70%>40%512+L, 2+P1+03+ L, 3+P2+
80%6%52+L, 1+P, 2+AI02+2+L, 2+P, 1+AI ∧2+
100%001+L, 1+P003+L, 1+P∗0
30%001+L, 1+P, 1+AI01+3+L, 1+P0
PT: peritubular, Inf: inflammation, L: lymphocytes, P: plasma cells, MGC: multinucleated giant cells, AI: acute inflammation. †patient with RA, ∗ focal eosinophils, ∧ focal MGC cells.

In GS, 10-100% of tubules with IGCNU (highlighted by PLAP) had a granulomatous reaction, which in 3 cases was so extensive that in areas it replaced IGCNU cells. In contrast to IGO, GS had more intratubular MGC (3/6 numerous & 3/6 focal), more (3/6) mild-moderate peritubular sclerosis, fewer interstitial plasma cells, and no interstitial fibrosis. Of the 4 GO cases: 3 had granulomatous inflammation that was predominantly interstitial and only focal intratubular (1 with fibrinoid vasculitis); 1 had numerous interstitial and intratubular MGC. Only 1 non-IGO case had elevated IgG4 (GS case): IgG4/IgG ratio (27%) & 13/HPF IgG4 plasma cells.
Conclusions: It is critical and sometimes difficult to distinguish GS from IGO. In addition to identifying IGCNU (possibly aided by PLAP), more numerous intratubular MGC in GS and interstitial plasma cells in IGO are helpful features. The diagnosis of IgG4-RD is organ specific. Although its occurrence in the testis has not been studied, based on criteria for other organs, 3 of our IGO cases qualify for a diagnosis of "probable" but not "highly suggestive" of IgG4-RD.
Category: Genitourinary (including renal tumors)

Tuesday, March 5, 2013 1:00 PM

Poster Session IV # 207, Tuesday Afternoon

 

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