嫌色素細胞腎癌16例の臨床病理学的検討

Abstract

病理組織学的に嫌色素細胞癌と診断された16例を対象に, 臨床病理学的検討を行った.病理組織学的に腎細胞癌と診断された症例は389例であり, 嫌色素細胞癌は16例, 4.1%であった.病理組織学的に嫌色素細胞癌単一型を示した14例のうち, 無症状で超音波, CTスキャンなど画像検査で発見された偶然例が10例を占めた.有症状例は4例で, 肉眼的血尿3例, 腹部腫瘤1例であった.年齢分布は16～74歳であった.14例は嫌色素細胞腎癌単一像, 1例が肉腫様癌との混合型, 1例がBellini管癌との混合型であった.嫌色素細胞腎癌単一型14例の予後は良好であったが, 肉腫様癌, Bellini管癌との混合型の2例は予後不良であった.造影CT, 血管造影では全例がhypovascular tumorの所見であった.予後不良の2例では術前診断時にCRP, IAPの上昇を認めた

Pathological characteristics, patient outcome, and preoperative examinations of 16 cases (4.1%) of chromophobe renal cell carcinoma (RCC) observed among 389 patients with RCC treated at Yokohama City University Hospital and Yokohama City University Medical Center between 1991 and 2004 were analyzed. The age distribution was 16 to 74 years old (average age; 50.9 +/- 17.0). Pathologically, 14 patients had pure chromophobe RCC, and two patients had chromophobe RCC coexisting with aggressive pathological elements, that is, sarcomatoid change in one patient and collecting duct carcinoma in the other. The average tumor size was 7.1 +/- 4.1 cm. On preoperative imaging studies with enhanced computed tomography or angiography, all cases showed a hypovascular pattern. C-reactive protein (CRP) and immunosuppressive acidic protein (IAP) were increased specifically in the two cases coexisting with aggressive pathological elements. Fourteen cases showing pure chromophobe RCC did not metastases on preoperative examination. Thirteen cases were treated by nephrectomy, and another was treated by partial nephrectomy. To date there have been no recurrences during the 6 to 160 months postoperative follow-up. The patient with a mixture of chromophobe RCC and sarcomatoid change (pT3aN0M0) died of multiple lung metastases 18 months after nephrectomy. The patient showing a mixture of chromophobe RCC and collecting duct carcinoma demonstrated metastases to the paraaortic lymph nodes at preoperative examination (pT1bN2M0), and died of multiple lung and bone metastases and carcinomatous peritonitis 8 months after nephrectomy. The patients with pure chromophobe RCC had a favorable prognosis, but those with a mixed type including aggressive elements such as sarcomatoid change or collecting duct carcinoma, showed a poor clinical course. The increase in CRP or IAP could predict poor prognosis in such cases.