Determinants and prognostic implications of malignant ascites in metastatic papillary renal cancer.

OBJECTIVE: To describe the incidence of ascites in metastatic papillary renal cell cancer (pRCC), identify the factors associated with its development and evaluate its prognostic effect on the survival of these patients. METHODS: A retrospective evaluation of the medical records of patients with metastatic pRCC seen at National Cancer Institute (2000-2014) was undertaken. Logistic regression to identify predictors of the development of malignant ascites and Kaplan-Meier analysis to estimate survival was done. RESULTS: Overall, 106 consecutive patients with metastatic pRCC were identified; sufficient data were available in 100 patients to enable assessment of ascites. Further, 20% had evidence of malignant ascites. Median age at diagnosis of ascites was 48.0 years (26.1-76.6 years) and median time to development of ascites from initial diagnosis of metastatic disease was 16.0 (0-73.3) months. There was no significant difference in the incidence of ascites between patients with hereditary and sporadic pRCC (P = 0.803) or among patients with different subtypes of pRCC (P = 0.456). Elevated platelet-lymphocyte ratio predicted development of malignant ascites in our cohort (P = 0.009). Median overall survival was shorter for patients who developed ascites [25.0 (10.2-39.8) months] compared with patients who did not develop this complication [42.5 (30.5-54.4) months, P = 0.041]. CONCLUSION: To our knowledge, this is the first systematic evaluation of the incidence, predictors, and prognostic effect of ascites in metastatic pRCC. Malignant ascites is a common manifestation of metastatic pRCC and is associated with a shorter overall survival. An elevated platelet-lymphocyte ratio predicts a higher risk of developing malignant ascites.

Targeting the mTOR pathway in Chromophobe Kidney Cancer.

Chromophobe kidney cancer accounts for approximately 5% of cases of renal cell carcinoma (RCC). While the genetics of clear cell RCC has been a major focus of research, little is known about the biology of chromophobe tumors. There is ample preclinical rationale for the use of targeted therapy in clear cell tumors, and agents targeting the VHL/HIF pathway are now widely used in clinical practice. However, there is limited experience with targeted agents in non-clear cell tumors. Recently, a few case reports have emerged which report the use of mTOR inhibitors in chromophobe tumors. Here, we report our experience with targeted therapy in a patient with advanced chromophobe RCC who had a durable partial response to temsirolimus. We also include a literature review summarizing the published experience with targeted therapeutic approaches in chromophobe RCC. Additionally, the preclinical rationale for the use of mTOR inhibitors in this population based on our characterization of the hereditary form of chromophobe kidney cancer, Birt-Hogg-Dube syndrome, is discussed.