Survivin expression in renal epithelial tumors: Its usage in the differential diagnosis of eosinophilic renal epithelial tumors A. Ozcan * , N. Yigit, O. Onguru, B. A. Firat, S. Ozaydin * Gulhane Military Medical Academy, Dept. of Pathology, Ankara, Turkey Objective: The differential diagnosis of renal tumors can be problematic due to overlapping morphologic features. The purpose of this study was to assess the potential contribution of survivin expression in the differential diagnosis and determination of therapy modalities of these tumors. Method: This study consisted of 15 chromophobe (ChRCC), 15 clear cell (CCRCC) and 9 papillary (PRCC) renal cell carcinomas, and 13 oncocytomas. Sections were stained against survivin antibody. Results: PRCCs and CCRCCs showed diffuse and strong survivin expression. Survivin expression was strikingly prominent in type1 PRCCs and cystic CCRCCs. In CCRCCs, survivin expression was more pronounced in low grade areas than high grade and sarcomatoid areas. In ChRCC, survivin expression was more limited and weaker than that of oncocytomas and other malignant renal tumors. In non-neoplastic renal tissue, survivin expression was more pronounced in podocytes and atrophic tubules than other nephron parts. Conclusion: Our findings suggest that survivin may contribute to the differential diagnosis of renal tumors because of the partially unique staining patterns. It was purposed that knockdown of survivin reduced growth, induce apoptosis and enhance in vitro radiosensitivity of RCC cells. Taken together, to be known different survivin expression patterns in renal tumors may help to determine new therapeutic strategies for RCCs. Objective: There are several tumor-like lesions and miscellaneous neoplasms of rete testis. We present a case with adenomatous hyperplasia of rete testis (AHRT). Method: The patient was 24 years old with undescended testis and referred to our hospital. There was no clinical or endocrin abnormalities. Cryptoorchidism was unilateral and the other testis was normal. Right orciectomy was performed and sent to pathology labarotory for examination. Results: There was no tumoral lesion in gross examination but in microscobic examination there was gland like tubular structures. Some of these were back to back position with little intervening stroma and mild to moderate atypia. EMA and pancytokeratin immunohistochemistry findings with morphology confirmed the diagnosis of AHRT in this case. Conclusion: AHRT is a rare proliferatif lesion and can be confused with malignancy. It is incidentally realised in microscobic investigation. It may present as a very small lesion detected in microscobic examination or solid-cystic mass lesion which is macroscobically evident. Clinic history, localization, histologic features and immunohistochemistry are criterias for differentiating these lesions.We present this case for both surgeons and pathologists with its importance to be confused with malignancy. Objective: Prostate cancer is the second leading cause of death in men. The localized disease often responds to conventional therapies like androgen ablation via castration and/or administration of chemical inhibitors but advanced disease resistant to any curative therapies is still challenge for investigators. There are increasing efforts to enhance the possibility of finding positive and sensitive immune markers for diagnosing and treating prostate cancer. Method: We applied immunohistochemical markers; AMACR and iNOS. Formalin-fixed parafin embedded tissues of 64 prostate needle biopsy specimens diagnosed as prostate adenocarcinoma between 2005 and 2010 years were enrolled in the study. Results: AMACR expression has been found in 58 (90.6 %) and iNOS expression in 54 (84.4 %) of 64 prostate adenocarcinomas.No significant relationship of AMACR and iNOS has been obtained (p>0.05). There was no significant correlation of histopathologic grade of the tumors with AMACR and iNOS expression (p>0.05). Conclusion: The expression of AMACR and iNOS might be important diagnostic immune markers for prostate adenocarcinomas especially in needle biopsies when the quantity and quality of tissue are limited.