治療反応性の異なる前立腺小細胞癌の2例

Abstract

症例1:76歳男。主訴は排尿困難で、PSA高値、画像検査で前立腺の腫瘍、腸骨リンパ節・鼠径リンパ節腫大、両肺野の多発性腫瘤を認めた。経会陰的前立腺針生検を施行し、小型でN/C比が高く、濃染した核を有する腫瘍細胞を認めた。免疫組織染色でNSE陽性であった。以上より前立腺小細胞癌と診断し、LH-RH analog、bicalutamideによるMAB療法を開始した。治療開始1ヵ月後にPSAは低値となり、3ヵ月後の胸部CTでは多発性肺転移は消失していたが、その後再燃を来たし、9ヵ月後に肺転移巣の再発を認め、徐々に全身状態が悪化し12ヵ月後に死亡した。症例2:79歳男。主訴は排尿困難で、PSAおよびNSE高値、画像検査で前立腺の腫瘍、腸骨リンパ節腫大を認めた。経尿道的前立腺切除を施行し、病理組織学的所見より前立腺小細胞癌と診断した。LH-RH analog、bicalutamideによるMAB療法を開始したところ、PSAは低下したが、NSEは上昇し続けた。治療開始1ヵ月後より下血、会陰部痛が出現し、徐々に全身状態悪化し5ヵ月後に死亡した。

Case 1 : A 76-year-old man with a chief complaint of dysuria had an elevated prostate specific antigen (PSA) level of 24.9. He underwent a transperineal needle biopsy of the prostate, and the histopathological diagnosis was prostatic small cell carcinoma. The cancer was clinically diagnosed as T3bN1M1 with multiple lung metastases. He started receiving hormonal therapy. After three months of hormonal therapy, the multiple lung metastases disappeared. Thereafter, the serum PSA level and the tumor volume increased and he died 12 months from the start of therapy. Case 2: A 79-year-old man was referred to our hospital with a chief complaint of dysuria. The serum level of PSA was elevated to 10.4. Transperineal prostate biopsy revealed prostatic small cell carcinoma. The cancer was clinically diagnosed as T3bN1M1, and hormonal therapy was started. Subsequently, although his serum PSA level declined, his condition worsened rapidly and he died five months after the start of therapy.