The Impact Of Gender And Age In Renal Cell Carcinoma: Age Is An Independent Prognostic Factor In Women But Not Men

5091 Background: Renal cell carcinoma (RCC) occurs twice as often in men as in women; however, the influence of gender on stage, grade, subtype and survival has not been studied in detail. If this imbalance in RCC incidence was related to gender-specific hormone levels, age could be a further significant variable. Methods: This study included 5,654 patients treated by nephrectomy at 10 international academic centers. Differences in gender, age, T, N, and M stage, Fuhrman grade, and histological subtype were evaluated with chi- square and Student’s t-tests. Kaplan-Meier survival estimates and Cox proportional hazards models addressed the impact of gender and age on disease-specific survival (DSS). Results: Of the 5,654 patients, 3,777 (67%) were men and 1,877 (33%) were women. Generally, women presented at lower T stages (p<0.001), less frequently had distant metastases (p<0.001) and had lower grade tumors (p<0.001). In addition, women more frequently had clear-cell (87% vs. 82%) and less frequently had papillary RCC (7% vs. 12%) than men (p<0.001). As a group, women had a 19% reduced risk of death from RCC than men (HR 0.81, 95% CI 0.73–0.90, p<0.001). Interestingly, the survival advantage for women was present to the greatest degree in the age group <40 years (p=0.0136), was intermediate in women aged 40–59 (p<0.001), and disappeared in patients aged 60 years and older (p=0.248). Among women, age was an independent predictor of DSS in multivariate analysis (HR 1.011, 95% CI 1.004–1.019, p=0.004). In contrast, age was not related to prognosis in men. Conclusions: Among women, age is an independent prognostic factor of DSS with the risk of RCC-specific death increasing by 1% with each year increase in age. As a group, women present with less advanced tumors, leading to a 19% reduced risk of RCC-specific death compared with men. This survival difference is present only in patients aged <60 years, but disappears in older patients. Since this gender based survival difference is not related to T, N, M stage, ECOG PS, or histological subtype, the role of estrogen on the development and progression of RCC needs to be studied. If a true estrogen effect on RCC does exists then the potential for hormone-targeted therapy in women will also need to be investigated. No significant financial relationships to disclose.