CLINICOPATHOLOGICAL STUDY ON PATIENTS WITH CHROMOPHOBE CELL RENAL CARCINOMA

(Background) Reports on the patiens with chromophobe cell renal carcinoma were very few. Therefore, the clinical features of this disease are uncertain. Based upon this background, we have studied on the clinicopathological characteristics of chromophobe cell renal carcinoma. (Patients and Methods) From 1957 to 1995, seven hundred and fifty-one patients with renal cell carcinoma (RCC) were treated at the Jikei University Hospitals. Of these patients, 36 (4.8%) with chromophobe cell renal carcinoma were diagnosed by histopathological examination. Of these 36 patients, the objective patients were 34 who could be followed-up along with long interval. (Results) The age distribution was 28 to 83 years old (mean was 54.1 years). Regarding to the sex difference, there observed male in 22 patients and female in 12 patients (sex ratio was 1.8:1). Furthermore, the affected side was even, but there observed the symptoms of urinary tract mainly of haematuria in 24 patients (76.5%). As to the laboratory examination, there observed the abnormality of the acute phase reactants in 20% of patients. The greater diameter of the tumour was distributed from 1.5 to 17cm (mean: 6.9cm), and no consistent tendency of tumour localization was observed. Regarding the preoperative angiography, there observed the hypovascular/avascular pattern in 15 patients (44.1%). As to the stage and grade, there observed the low stage patients in 30 (88.2%) and low grade patients in 27 (79.4%). With respect to the prognosis, the 1, 3, 5, 10, 15 and 20 years survival rates for chromophobe cell renal carcinoma were 97.1%, 81.6%, 81.6%, 70.2%, 61.9% and 46.7% respectively. After comparing the survival rate of the same stage and grade patients between the objected patients and the common types of RCC, there observed a favourable prognosis in the patients with chromophobe cell renal carcinoma. Especially in patients with eosinophilic variant, no cancer related death was observed. (Conclusion) The clinicopathological characteristics of chromophobe cell renal carcinoma show the hypovascular/avascular in angiography, low rate of laboratory abnormality, low stage/low grade and a favourable prognosis compared with the common types of RCC.