Purpose: To compare the effect of high-dose interleukin-2 (HD IL-2) vs other cytokine therapies on 1-, 2, and 5-yr overall survival in patients with metastatic renal cell cancer (RCC).
Patients and methods: We conducted a retrospective chart review of patients with untreated metastatic RCC treated by a single investigator. The different treatment groups included HD IL-2, low-dose IL-2 alone or in combination, interferon alpha alone and other therapies. The primary end point was survival from time of treatment.
Results: A total of 85 patients were studies with a median follow up of 13 mo (0.6-112.9). Median age at treatment was 59 yr with predominantly male patients and histology of clear cell type. Thirty-four percent received HD IL-2 and treatment was initiated less than 6 mo from the time of diagnosis in 66%. For all patients, median survival was 16 mo with a 5-yr survival of 12%. Two factors were good predictors of overall survival: Karnofsky performance status (KPS) of 100 (p < 0.0001) and soft tissue metastasis (p = 0.01). When comparing HD IL-2 to all other groups, median survival was 18 vs 14 mo and 1-yr survival was 74% vs 51%, respectively.
Conclusion: HD IL-2 is associated with clinically meaningful improvement in median and 1-yr survival.