Interferon gamma in survivors of the Chernobyl power plant accident: new therapeutic option for radiation-induced fibrosis.

Abstract

One of the remarkable clinical consequences of the Chernobyl accident was skin involvement, leading to extensive cutaneous fibrosis. Apart from surgery, no established treatment is available. A group of survivors, working in or present at the accident site on April 26, 1986, and a few days thereafter, were examined, treated, and followed-up in 6-month intervals from September 1991 to November 1995. Eight individuals were identified as suffering from excessive cutaneous fibrosis. Skin thickness was measured with high-frequency (20 MHz) ultrasound in a clinically well-defined target skin lesion, in addition to histologic confirmation of radiation fibrosis. Interferon gamma was scheduled for all patients on a low-dose regimen (3 x 50 microg/week s.c.). In 2 patients, interferon was discontinued after the first injection, due to withdrawal of consent. In 6 patients, interferon was continued for 30 months, with 1 injection weekly for a further 6 months. Treatment was discontinued in November 1994. Four patients in the treated group and 1 of the 2 patients treated only once ("untreated patients") were reexamined 1 year later. In all individuals treated for 36 months, a significant (p < 0.005) reduction of radiation fibrosis could be determined, in contrast to a significant (p < 0.005) increase in the 2 untreated patients. Follow-up 1 year after discontinuation of the interferon treatment demonstrated significant (p < 0.005) recurrence of fibrosis. Low-dose interferon appears to be a safe and effective treatment of cutaneous radiation fibrosis following accidental exposure to high doses of ionizing radiation. Long-term supportive therapy may be required.