Sporadic bilateral renal cell carcinoma (RCC) is relatively rare in RCC. Sporadic bilateral RCC is a distinct subtype and has different biological behaviors compared with hereditary bilateral RCC. The latter occurrence does not bear a significantly worse pathologic biology in metachronous bilateral RCC. The prognosis of patients with sporadic bilateral RCC is comparable with that of patients with unilateral RCC.Introduction:
The purpose of this study was to investigate the clinicopathologic features, treatment, and prognosis of sporadic bilateral renal cell carcinoma (RCC).Patients and Methods:
A total of 148 patients with sporadic bilateral RCC treated in our center from June 1986 to December 2015 were included in this retrospective study. Their clinicopathologic features and treatments were evaluated. The survival and prognostic factors were assessed based on data from follow-up.Results:
The median age was 54 years (range, 31-78 years). There were 88 patients with synchronous bilateral RCC and 60 with metachronous bilateral RCC. The median interval between bilateral tumors of metachronous bilateral RCC was 75.5 months. There was no significant difference in tumor size, nuclear grade, or T stage between metachronous tumors (P = .385, P = .544, and P = .263, respectively). Of 148 patients, 124 patients underwent bilateral surgery, 16 underwent unilateral surgery, and 8 patients did not undergo surgery. Of the 317 tumors with pathologic results, 297 (93.7%) were clear-cell subtype. A total of 136 (91.9%) patients were followed-up, and the median follow-up period was 77 months (range, 2-398 months). During follow-up, 38 (27.9%) patients died. The 5-year overall survival rate was 85.9%. The median survival time of patients with no surgery was 5 months. Older age (P = .001), bilateral nonoperative treatment (P < .001), higher T stage (P < .001), and multifocality (P = .02) were related to worse prognosis in multivariate analysis.Conclusion:
In metachronous bilateral RCC, the latter occurrence does not bear a significantly worse pathologic biology. The prognosis of sporadic bilateral RCC with no surgery is poor. The overall oncologic results of patients with sporadic bilateral RCC are comparable with that of patients with unilateral RCC.