Renal metastases to pancreas: do not operate all and always?

Aim Methods Data from 19 Italian centers involved in the treatment of metastatic RCC were retrospectively collected. Kaplan-Meier and log-rank test methods were used to evaluate the overall survival (OS). Clinical variables considered were sex, age, concomitant metastasis to other sites, surgical resection of PM-RCC and time to PM-RCC occurrence. A subsequent univariate and backward multivariate Cox regression model was fitted to the data to correct for the effect of covariates. Results 103 patients were enrolled in the analysis; 66 of them were males. Median age was 67 yrs (range 43–85 yrs). PM-RCC were synchronous in only 3 patients (3%). In 56 patients (54%), the pancreas was the only metastatic site, whereas in the other 47 patients lung (57%), lymph nodes (28%) and liver (21%) were the most common concomitant metastatic sites. Median time for PM-RCC occurrence was 9.6 yrs (range 0–24 yrs) after nephrectomy. Surgical resection of PM-RCC was performed in 40 patients (39%) and consisted of total (21%), distal (71%) or central pancreatectomy (8%). Median OS was not reached in patients who underwent surgical resection of PM-RCC and 11.1 yrs in the unresected patients (p < 0.001). At univariate analysis, only the presence of concomitant metastases to other sites (p = 0.008) was significantly associated with a poor prognosis, whereas none of the evaluated variables were independent prognostic factors at multivariate analysis. Conclusions The presence of PM-RCC is associated with long survival, which is surprisingly not associated with surgical resection, time of PM-RCC occurrence and the presence of concomitant metastases to other sites, although these data should be confirmed in a larger population.