Prognosis of patients with metastatic renal cell carcinoma and pancreatic metastases.

Abstract

527 Background: Pancreatic metastases are seen in a relatively small percentage of patients with renal cell carcinoma (mRCC). The prognostic impact of pancreatic metastases in patients receiving treatment for mRCC has not been extensively studied, and drivers of pancreatic metastases are not known. Methods: Retrospective review of mRCC patients in an outpatient clinic was done from January 2006 to November 2011. Patient characteristics including demographics, laboratory data, and outcomes were analyzed. Comparison of baseline characteristics was done using chi2and t-test and overall survival (OS) was estimated using Kaplan-Meier methods. Predictors of OS were analyzed using Cox regression. Results: A total of 228 patients were reviewed of which 44 (19.3%) had metastases to the pancreas and 184 (81.7%) had metastasis to sites other than the pancreas. The distribution of baseline characteristics and other factors was equal in both cohorts. 4 patients had isolated metastases to the pancreas, however, the majority of patients (68%) with pancreatic metastases had at least three different organ sites of metastases, as compared to 29% in patients without pancreatic metastases (p<0.01). Distribution of organ sites of metastases was similar (p>0.05), excluding pancreas. Median OS was 39 months (95% confidence interval [CI], 24-57) for patients with pancreatic metastases, compared to 26 months (95% CI, 21-31) for patients without pancreatic metastases (p-value <0.01). Conclusions: Despite a higher number of affected organ sites in the pancreatic metastasis cohort, mRCC behavior in this cohort appears to be more indolent, as demonstrated by a higher median OS. These findings suggest that host or tumor features associated with pancreatic metastases induce a less aggressive tumor phenotype. [Table: see text]