452 Background: Administration of high-dose interleukin-2 (IL-2) in metastatic renal cell carcinoma (MRCC) has higher response and survival rates when compared to low dose or subcutaneous administration. In patients who achieve a response, it may be at the expense of more toxicity risk, from more doses. The association of the major response rate with the number of high dose boluses or cumulative dose received is of interest. The primary objective of this study is to evaluate a direct correlation with response and cumulative dose or the total number of doses received. Methods: A retrospective chart review was conducted of all patients at H. Lee Moffitt Cancer Center diagnosed with metastatic renal cell carcinoma who received high dose bolus IL-2 from September 30th, 1999 to September 30th, 2010. The cumulative dose and the number of doses of IL-2 received was recorded and associated with categorical complete response [CR], partial response [PR], stable disease [SD] or progressive disease [PD] response, by treating physician assessment. Sites of metastasis were also documented. The incidence of adverse effects such as renal failure, transaminitis, cardiac arrhythmias, thrombocytopenia as well as rates of infection and ICU transfers were tabulated. Results: 31 out of 55 patients analyzed were assessed at least with stable disease in response to IL-2. Six achieved a CR, 11 achieved a PR, 14 had stable disease and 24 patients had PD as best responses. Among those with CR or PR to IL-2, they received approximately 30 doses of IL-2 (p=0.027 vs. those not in that category). Converesely, those who received a higher cumulative dose were also more likely to respond (p=0.0077). With respect to adverse events, 58% of patients experienced acute renal insufficiency, 63% transaminitis, 40% arrhythmias, and 45% thrombocytopenia. 55% required dopamine use at any point and 11% required use of additional pressors; 15% required an ICU transfer at some point, and approximately 4% developed a documented infection. Conclusions: Cumulative dose or number of high dose bolus doses received is associated with a statistically significant difference in response rate, within the limitations of this retrospective analysis.
A Phase I Study of High-Dose Interleukin-2 With Sorafenib in Patients With Metastatic Renal Cell Carcinoma and Melanoma
