WHO Melanoma Study: Interferon Boosts Disease-Free Survival

LISBON, Portugal--Adjuvant immunotherapy with low-dose interferon(IFN)-alfa-2a (Roferon-A) boosts disease-free survival by a significant40% in melanoma patients with regional lymph node metastasis,according to the findings of the latest multicenter World HealthOrganization (WHO) Melanoma Programme trial.

After undergoing radical surgery, 218 participants in this studywere randomized to receive IFN-alfa-2a, 3 million units subcutaneously,thrice weekly for 3 years, while 209 received no further treatment.At a mean follow-up of 22 months, 45% of IFN-treated patientswere alive and disease-free, compared with only 32% of controls,said Dr. Natale Cascinelli, of the National Cancer Institute,Milan, who is president of the WHO Melanoma Programme.

Speaking at the congress of the European Society of Medical Oncology,Dr. Cascinelli also noted a trend toward improved overall survival,pointing out, however, that definitive evidence of a statisticallysignificant overall survival advantage must await longer follow-up.

Dr. Cascinelli called the results highly encouraging, particularlyin light of the fact that in patients with stage II melanoma,most adverse events tend to occur during the first 24 months.

The WHO investigators found that the response to adjuvant immunotherapyhinged not only on the number of positive nodes but also on thepatient's age and gender. They observed that disease-free survivalincreased with increasing age in men who received IFN-alfa-2abut, conversely, declined with increasing age in IFN-treated women.

Dr. Cascinelli speculated that the lesser benefit of IFN treatmentin women over the age of 50 might mean that the effect of theimmune stimulant is mediated by sex hormones.

"We are now conducting experiments in the laboratory to determinewhether the actions of IFN are potentiated by estrogens,"he said.

The only major toxic effect of IFN-alfa-2a in this trial was fever,but in no case did this necessitate dose reduction, Dr. Cascinellireported. In addition, quality of life measurements performedat the National Cancer Institute, Milan, indicated that this treatmenthad no untoward effects on patient well-being.

Three-Year Treatment Course

After completing the 3-year course of IFN treatment, WHO studyparticipants will be followed to ascertain whether the cessationof immunotherapy is associated with a decline in disease-freesurvival, Dr. Cascinelli said.