Chromophobe renal cell carcinoma: analysis of 61 cases.

Background: Chromophobe renal cell carcinoma (CRCC) is often associated with a favorable prognosis. However, to the authors' knowledge, only few clinical data are available regarding this variant of tumor. In the current study, the authors report their experience with CRCC over the last 14 years.
Methods: Since 1989, 61 patients have been treated at the study institution for CRCC. Tumor characteristics and patient outcome were analyzed retrospectively. Data were obtained from the patients' medical records.
Results: The mean age of the patients was 58 years. Of the 61 tumors, 68.8% were discovered incidentally. The mean tumor size was 6.9 cm. Fifty-seven patients (93.4%) were treated with radical nephrectomy and 4 patients (6.6%) underwent partial nephrectomy. According to the 1997 TNM classification, the pathologic tumor stage was T1 in 65.6% of cases, T2 in 31.1% of cases, and T3a in 3.3% of cases. All tumors were staged as N0M0. Nuclear grade was low (1 or 2) in 88.5% of cases. In no case of CRCC was a sarcomatoid component observed. At a mean follow-up of 49.5 months (range, 5-135 months), no patient had experienced tumor recurrence or disease progression, and none had died of renal carcinoma.
Conclusions: In the authors' experience, CRCC carries an excellent prognosis, possibly due to the high rate of low-stage and low-grade tumors.
(Copyright 2004 American Cancer Society.)