A 77-year-old man was referred to our hospital with a complaint of dysuria and right ischiodynia. He had had a hemi-thyroidectomy for thyroid cancer and right cervical lymphadenectomy three years and one year, respectively, before this visit. Prostate cancer was strongly suspected by transrectal examination with prostate specific antigen (PSA) elevated to 77.8 ng/ml. Pathological diagnosis of prostate biopsy specimen was transitional cell carcinoma with grade 3 malignancy and negative staining for PSA. Endoscopic examination showed a normal appearance of bladder and prostatic urethral epithelium. Urine cytology showed no malignant cells. However, immunostaining for PSA revealed that the cervical lymph node specimen resected before was moderately differentiated adenocarcinoma of prostate. He had multiple metastases to mediastinal and retroperitoneal lymph nodes and right ischium. Endocrine therapy (goserelin acetate depot, bicalutamide) and systemic chemotherapy (methotrexate, epirubicin, cisplatin) were performed combined with irradiation to right ischium metastasis. Two months later, he showed a complete response in PSA and partial response in lymph node metastases, but died of cancer 13 months later.