Adenocarcinoma of the prostate with ectopic antidiuretic hormone production: a case report

Abstract

88歳男, 尿閉を主訴とし, 前立腺特異抗原(PSA)値, 直腸診所見から前立腺生検を施行し, 低分化型腺癌と診断された.血液生化学検査の結果, 抗利尿ホルモン(ADH)分泌異常症候群診断基準を満たしていた.また血中及び前立腺癌組織中のADH値の上昇を認め, 免疫組織化学的検査において腫瘍細胞はPSAに陽性で, ADHに対しても軽度陽性であった.酢酸リュープロレリンとフルタミドによる抗アンドロゲン療法に反応し, 90日後には血液生化学所見も正常となったが, 治療開始6ヵ月後に胃潰瘍からの大量出血により死亡した.異所性ADH産生性前立腺癌症例は本症例を含め10例目の報告である

An 88-year-old patient with a poorly differentiated adenocarcinoma of the prostate gland was found to have all cardinal findings of syndrome of inappropriate antidiuretic hormone secretion (SIADH). Elevated levels of antidiuretic hormone were found in the patient's serum and in the prostatic tumor and the cytoplasms of the tumor was positive for prostate specific antigen and was faintly positive for antidiuretic hormone (ADH). He responded well to combination therapy of androgen blockade with leuprorelin acetate and flutamide, and laboratory findings of SIADH and serum ADH level returned to normal. However, he died of sudden profuse bleeding caused by gastric ulcers 6 months after the therapy. Ten cases of SIADH caused by prostatic cancer have been reported including the present case.