Interferon alpha 2b as medical selection for nephrectomy in patients with synchronous metastatic renal cell carcinoma: a consecutive study.

Objective: Up to 25% of the patients with synchronous metastatic renal cell carcinoma (mRCC) treated with nephrectomy and interferon alpha-2b (IFN-alpha) will progress rapidly at metastatic sites and undergo needless surgery for an asymptomatic primary. We reversed the timing of surgery and immunotherapy and evaluated the role of initial IFN-alpha as selection for nephrectomy.

Patients And Methods: Sixteen patients with mRCC and the primary in-situ received initial IFN-alpha for 8 weeks (2 weeks 5x3x10(6)IU/wk; 2 weeks 5x6x10(6)IU/wk; 2 weeks 5x9x10(6)IU/wk and 2 weeks 3x9x10(6)IU/wk). Patients with either partial remission (PR) or stable disease (SD) underwent nephrectomy followed by IFN-alpha maintenance at 3x9x10(6)IU/wk. Patients were evaluated with regard to age, sex, metastatic sites, morbidity, response, nephrectomy rate, time to progression and survival.

Results: Thirteen patients received 2 months of preoperative IFN-alpha; 3 stopped during the 2 months period due to progressive disease (PD). Eight patients developed either a PR (n=3) or SD (n=5) at metastatic sites and underwent nephrectomy. Survival at 1 year is 50% (4/8 patients). Median progression-free survival was 6 months (3-17 months). Two of the 3 patients with PR developed a CR after 2 months maintenance following surgery. Eight patients with PD did not undergo surgery and had a median survival of 4 months (range 1-8 months).

Conclusions: Absence of progression at metastatic sites following IFN-alpha with the primary tumor in place may be used as selection for nephrectomy in patients with an intermediate prognosis. Currently, a randomized study is underway to assess the role of initial versus delayed nephrectomy in combination with IFN-alpha with regard to morbidity and survival.