High-dose Interleukin-2 Can Produce a High Rate of Response and Durable Remissions in Appropriately Selected Patients With Metastatic Renal Cancer

Metastatic renal cancer remains hard to treat and the treatment is generally palliative. However, high-dose interleukin-2 (HD IL-2) produced 5% to 10% complete remissions and most of these were durable. With the advent of newer treatments with less toxicity, the role of HD IL-2 is uncertain. We present here a case series of 72 patients with metastatic renal cancer given first-line treatment with HD IL-2. From 2003 to 2006, the patients were offered treatment with HD IL-2 irrespective of their histologic features (retrospective cohort). From 2006 to 2008, the treatment was only offered to patients after stratification into risk groups based on histologic criteria (prospective cohort). In the early series, the response rate to HD IL-2 was 27% (8/30), but with prospective stratification of patients by histology the response rate was 52% (21/40) in the group with favorable histologic features. Combining outcome for all patients with the favorable histology (including those identified retrospectively) 49% (28/57) responded with 25% (14/57) achieving a complete remission and these seem durable. Patients with metastatic renal cancer should be carefully assessed for their suitability to undergo treatment with first-line systemic therapy with HD IL-2 as in carefully selected patients it has a high-rate response and durable remissions.