ABSTRACT
Objective To study the clinical and pathologic features of chromphobe renal cell carcinoma (ChRCC) and to evaluate the conventional pathologic prognostic parameters in prognosis.Methods Seventy-five cases (42 males and 33 females) with pathological confirmed ChRCC (36 on the left and 39 on the right kidney) after nephrectomy during 1998 to 2009 were retrospectively analyzed. Patient's age ranged from 25 to 74 years, with a mean age of 56 years. Evaluation of conventional prognostic parameters was carried out. Kaplan-Meier survival curve was used to study the survival relationship. Results The mean tumor diameter was 7.3 cm. The majority of tumor macroscopic surface color was gray and yellow or gray and red. The majority of tumor cells were big polygon chromphobe cell or small round eosinophils. The TNM stages of these ChRCC were as follows: 30 cases in T1N0M0, 1 in T1N0M1, 26 in T2N0M0, 1 in T2N0M1, 11 in T3N0M0, 3 in T3N0M1, 1 in T3 N1 M0, 1 in T4 N0 M1 and 1 in T4 N1 M1. The pathologic grade of ChRCC was G1 in 3 cases, G2 in 24cases, G3 in 46 cases and G4 in 2 cases. All the 75 cases were followed up for 9 to 93 months (mean 44months), 7 patients died and others were alive without recurrence and metastasis. 3-year and 5-year survival rates were 93.3% and 90. 7%, respectively. The univariable analysis showed that tumor size (P=0. 028), TNM stage (P＜0. 001) were associated with tumor progression. The multivariable Cox regression model revealed that TNM stage was an independent predictor of aggressive ChRCC. Conclusions The ChRCC tumors are generally larger than other types of RCC and with a favorable prognosis. Fuhrman nuclear grade is not suitable for ChRCC. TNM stage is an independent predictor of aggressive ChRCC.