Tamoxifen and alpha interferon in advanced breast cancer.

Thirteen pretreated advanced breast cancer patients received a combination of alpha interferon 5 million IU every 2 days, subcutaneously, plus tamoxifen 10 mg 3 times daily, until disease progression. The objective response rate was 15.4%: 1 patient achieved a complete response, 1 a partial response and 11 demonstrated stable disease; half of the patients were receptor negative and/or pretreated with hormonotherapy. Durations of response were 16 and 26 months for the CR and PR patients respectively; median progression-free survival was 4 months (range 0-26). Toxicities were registered according to WHO criteria: 4 patients stopped the treatment with interferon because of severe flu-like symptoms, while in the others the combination was generally accepted with good tolerance.