Temporal change in risk of metachronous contralateral renal cell carcinoma: influence of tumor characteristics and demographic factors.
OBJECTIVE
To determine the relative risk (RR) of developing a metachronous contralateral renal tumor after an initial diagnosis of renal cell carcinoma (RCC), with stratification by renal tumor characteristics, demographic factors, and follow-up duration, in order to develop an improved risk-based surveillance strategy.


METHODS
The 1973 to 1997 Surveillance, Epidemiology, and End Results database was used to determine the observed and expected number of metachronous contralateral renal tumors developing after an initial diagnosis of RCC.


RESULTS
A total of 43,483 patients had a first diagnosis of RCC. Contralateral RCC developed subsequently in 155 (0.4%) of 40,049 patients with follow-up who had no synchronous diagnosis of RCC, with 10.81 expected cases (RR, 14.3; 95% CI, 12.2 to 16.8). The respective RRs (and 95% CIs) for contralateral RCC for white men and women were 16.0 (11.1 to 22.3) and 13.7 (7.7 to 22.6) at less than 2 years, 8.8 (5.0 to 14.3) and 10.5 (5.0 to 19.3) at 2 to 5 years, 13.5 (8.1 to 21.0) and 5.1 (1.4 to 13.2) at 5 to 10 years, and 13.0 (6.2 to 23.9) and 13.7 (5.0 to 29.9) at > or = 10 years, respectively. The RRs were significantly higher in black compared with white men for the first 5 years, with the RRs (and 95% CIs) in the former group of 95.3 (58.2 to 146.7) at less than 2 years and 41.9 (16.8 to 86.3) at 2 to 5 years.


CONCLUSIONS
The incidence of metachronous contralateral RCC is stable on long-term follow-up, suggesting that surveillance of the contralateral kidney should remain rigorous on extended follow-up. Black men are at a significantly higher risk of developing contralateral RCC in the first 5 years of follow-up.
Rabbani
Farhang
F
Department of Urology, Memorial Sloan-Kettering Cancer Center, New York, NY 10021, USA. rabbanif@mskcc.org
Herr
Harry W
HW
Almahmeed
Taghreed
T
Russo
Paul
P
D000328:Adult; D001741:Black or African American / Q000706:statistics & numerical data; D000368:Aged; D000369:Aged, 80 and over; D002292:Carcinoma, Renal Cell / Q000453:epidemiology* / Q000208:ethnology; D016009:Chi-Square Distribution; D005260:Female; D006801:Humans; D015994:Incidence; D007680:Kidney Neoplasms / Q000453:epidemiology* / Q000208:ethnology; D008297:Male; D008875:Middle Aged; D016609:Neoplasms, Second Primary / Q000453:epidemiology* / Q000208:ethnology; D016012:Poisson Distribution; D011159:Population Surveillance; D018570:Risk Assessment; D018426:SEER Program; D014481:United States / Q000453:epidemiology; D044465:White People / Q000706:statistics & numerical data