Background

Metastatic renal cancer remains hard to treat and treatment is generally palliative. However in historic series, high-dose interleukin-2 (HD IL-2) produced 5-10% 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.

Method

We present here a case series of patients with metastatic renal cancer treated with high dose interleukin-2. 72 patients were given first-line treatment with HD IL-2. From 2003 to 2006 patients were offered treatment with HD IL-2 irrespective of their histological features (retrospective cohort). From 2006-2008 treatment was only offered to patients after stratification into risk groups based on histological criteria (prospective cohort). More recently patients who have previously been treated with Sunitinib and up to two other targeted agents have been treated provided their histology was also “favorable”.

Results

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 histological 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 which appear durable. Patients who have previously received Sunitinib and other targeted agents have a similar rate of response although it is currently too early to assess durability of response.

Conclusion

Patients with metastatic renal cancer should be carefully assessed for their suitability to undergo treatment with systemic therapy with HD IL-2 as in carefully selected patients it has a high rate response and more durable remissions than can be achieved with other treatments. A randomised trial of HD IL-2 is warranted compared to the current first line standard treatment with Sunitinib to confirm the advantage in terms of durable complete remissions.