1392P - Increased Incidence of Renal Cell Carcinoma (RCC) Among Melanoma Patients

Abstract

ABSTRACT Purpose There is scant evidence for an increased risk for developing RCC among melanoma patients (pts), and evidence for possible risk factors for the association between melanoma and RCC is lacking. We examined the risk of developing both melanoma and RCC, and also the possible risk factors. Methods We searched our institutional tumor registry for pts with a diagnosis of melanoma and RCC. We used summary statistics to describe the population of pts and calculate total person-years at risk for RCC. We computed standardized incidence ratios (SIRs), which is the ratio of the observed to the expected number of pts with RCC among pts with melanoma using the Cohort Analysis for Genetic Epidemiology program. The expected number of pts with RCC was determined from SEER data. The 95% confidence intervals (CI) for the SIRs were determined by assuming a Poisson distribution for the observed number of RCC. SIRs were also calculated for subsets of the data according to race and gender. Results Between 1980 and 2005, we identified 15,482 pts with a diagnosis of melanoma: 59% were male and 94% were white. Among these pts, 114 (0.7%) pts had a diagnosis of RCC either before or after the diagnosis of melanoma. The mean age of RCC presentation was 59.4 years. The total person-years at risk for RCC were 886,506. We observed a significant excess of RCC (SIR = 1.64, 95% CI = 1.37-1.95) among our cohort of melanoma pts. This excess of RCC was also significant among white pts (SIR = 1.64, 95% CI = 1.36-1.92) and among both genders. None of the 114 pts with a diagnosis of both melanoma and RCC had a concomitant diagnosis of immunocompromised disease nor received chronic immunosuppressive drugs. Only 17% of the pts received radiation or chemotherapy for melanoma. Conclusions There is an increase risk of RCC among melanoma pts. Neither preexisting immunocompromised condition nor the chronic use of immunosuppressants were risk factors for developing both malignancies. Group Observed Expected SIR (95% CI) for development of RCC All (n = 15482) 114 69.53 1.64 (1.37-1.95) Gender M (n = 9072) F (n = 6410) 81 33 54.85 14.67 1.48 (1.19-1.82) 2.25 (1.61-3.08) Ethnicity White (n = 14580) Non-White (n = 902) 109 5 66.37 3.15 1.64 (1.36-1.96) 1.59 (0.70-3.25) Disclosure All authors have declared no conflicts of interest.