Signet-Ring Cell Change In Benign Prostatic Hyperplasia - A Rare Case Report

Signet-ring cell change (SCC) is a non-neoplastic condition that morphologically simulates signet ring cell carcinoma (SRCC) both of which are rare entities in the prostate. Herewith, we report a case of 66 year old man with benign prostatic hyperplasia showing SCC in the stroma and discuss the case from a review of published reports. Introduction SCC in the prostate is very rarely encountered. Identification of this lesion as a non-neoplastic condition is important to distinguish it from SRCC, a rare prostate malignancy. It is the lymphocytes and benign stromal cells in the prostate that exhibit the SCC. SCC can also result from hormone therapy prior to surgical intervention. Signet ring cells can also be seen in the prostate as metastatic deposit or by direct extension from the urinary bladder. Our aim is to identify SCC and avoid misdiagnosis of SRCC. Case Report(s) A 66 year old man presented with symptoms of urinary obstruct ion. The serum PSA is 7.6 ng/ml. Transurethral resection of prostate was done. Histopathological examination of TURP bits showed features of fibromusculoglandular hyperplasia of prostate. A significant finding was the presence of vacuolated cells with nuclei pushed to the periphery, in the stroma. These cells mimicked signet ring cells. The possibility of cancer was ruled out as multiple sections did not reveal the histopathological features of malignancy. Special stains like Alcian blue, PAS and mucicarmine stains were also negative. Discussion Signet ring cells in the prostate is extremely rare and can be seen in both non-neoplastic and neoplastic conditions. A review of the literature also shows case reports of signet ring cells present as artifacts. Alguacil-Garcia have reported 20 cases of transurethral prostatectomy showing signet ring cells in the stroma associated with dense lymphocytic in f i l t ra tes .1 The absence o f muc in and immunoreactivity for PSA and PSAP was also observed. Ultrastructurally, degenerated lymphocytes as well as vacuolated smooth muscle cells were noted in their study. They concluded in their study that areas of chronic prostatitis in TURP specimen usually showed degenerated lymphocytes and stromal cells with signet ring appearance, an artifact induced by TURP procedure[1,2]. Signet ring appearance can mimic carcinoma. A review of the literature reveals 43 cases of primary SRCC of prostate reported till date[3]. Almost all of the reported cases have been associated with high grade prostatic adenocarcinoma[3,4]. Serum PSA value was usually significantly elevated. These tumors exhibit more aggressive behaviour than conventional adenocarcinoma and are associated with poor prognosis[5]. The signet ring cells in these cases comprised of >25% of the tumor. Special stains for mucin was negative. Immunohistochemically the cells were positive for PSA and PSAP[6]. SRCC metastasizing to the prostate is an extremely rare phenomenon. However direct extension from the urinary bladder needs to be ruled out. SCC can be induced by prior hormone therapy in cases of prostatic adenocarcinoma. Conclusion Artifactual presence of signet ring cells in the prostate can occur and needs to be distinguished from carcinoma, primary or metastatic. References 1. Alguacil-Garcia A. Artifactual changes mimicking signet r ing cell carcinoma in transurethral prostatectomy specimens. Am J Surg Pathol. 1985 10 : 759-800. Webmedcentral > Case Report Page 2 of 8 WMC00688 Downloaded from http://www.webmedcentral.com on 24-Aug-2011, 07:04:45 AM 2. Wang HL, Humphrey PA. Exagerated Signet – ring cell change in stromal nodule of prostate : a pseudoneoplastic proliferation. Am J. Surg. Pathol. 2002 Aug;26(8):1066-70. 3. Cukur Selma, Alper Murat, Cam H. Kamil. Primary Signet Ring Cell Carcinoma of the Prostate. Medical Journal of Trakya University. 2006;23(3) : 155-157. 4. Kuroda N, Yamasaki I, Nakayama H, et al. Prostatic signet-ring cell carcinoma : case report and literature review. Pathol Int. 1999 May;49(5):457-61. 5. Saito S, Iwaki H. Mucin – producing carcinoma of the prostate : review of 88 cases. Urology 1999;54:141-4. 6. Ro JY, el-Naggar A, Ayala AG, et al. Signet-ring-cell carcinoma of the prostate. Electron microscopic and immunohistochemical studies of eight cases. Am J Surg Pathol. 1988 Jun;12(6) : 453-60. Webmedcentral > Case Report Page 3 of 8 WMC00688 Downloaded from http://www.webmedcentral.com on 24-Aug-2011, 07:04:45 AM