A case of prostatic cancer discovered from lung metastatic lesions

70歳男性.患者は検診時に胸部X線上の異常陰影, PSAの異常高値を指摘され, 著者らの施設へ紹介入院となった.入院時, 胸部X線・CTでは多発性結節影を認め, 骨盤部CTではリンパ節腫大を認めた.更に骨シンチでは右恥骨部に異常集積を認め, 前立腺生検では中分化から低分化腺癌の増殖を認めた.以上より, 肺・骨盤内リンパ節・骨転移を伴う前立腺癌stage D2と診断し, 内分泌療法(CAB療法)を開始した.治療開始6ヵ月後でPSAは感度以下となり, 16ヵ月現在, 肺転移巣は縮小瘢痕化し, リンパ節腫大および右恥骨部の異常集積も消失した
We report a case in a 70-year-old patient indicated to have a metastatic lesion from a chest X-ray taken during a medical examination. His blood prostatic specific antigen level was very high at 100 ng/ml (normal, less than 4.0 ng/ml). Palpation of the prostate disclosed enlargement to hen's egg size with an irregular surface and indurations bilaterally. Transrectal sextant needle biopsy of the prostate was performed, revealing moderately differentiated adenocarcinoma. Computed tomography (CT) scan and bone scintigraphy showed intrapelvic lymphnode adenopathy and metastasis to the right pubic bone. Under a diagnosis of stage D2 prostate cancer, we initiated endocrine therapy (luteinizing hormone-releasing hormone analogue depot every 4 weeks and bicalutamide). Androgen blockage was very effective and after 6 months, the PSA level had decreased markedly to below 0.2 ng/ml. Sixteen months later, pulmonary metastasis completely disappeared. He is currently free from recurrence and progressing well.