BACKGROUND: Multiple primary tumors in the same patient are reported to occur in the range of 2–17%. Histopathological recognition of an unsuspected tumor is important as it could influence therapeutic decisions and affect patients’ prognosis, but synchronous concomitant malignancies can be a diagnostic challenge for the pathologist. CASE: We report a case of prostatic acinar adenocarcinoma metastatic to a pelvic lymph node also affected by Hodgkin disease in a 73yearold man. After prostatic biopsies positive for prostatic adenocarcinoma, the patient underwent a radical prostatectomy with bilateral pelvic lymphadenectomy. Pathological examination confirmed the initial diagnosis, revealing a bilateral highgrade prostatic adenocarcinoma involving about 70% of the prostate with extensive extracapsular invasion. A metastasis of prostatic adenocarcinoma was found in 1 of the left pelvic lymph nodes; all pelvic lymph nodes showed an architectural effacement due to a distinct neoplastic proliferation characterized by large cells consistent with ReedSternberg and Hodgkin cells, confirmed by immunohistochemistry reactions. CONCLUSION: This case is, to the best of our knowledge, the first case of a urological neoplasm, namely a prostatic acinar adenocarcinoma, metastasizing to a lymph node simultaneously involved by Hodgkin disease. © Science Printers and Publishers, Inc.