Abstract
Thirty-six patients with histologically verified midgut carcinoid tumours and liver metastases were included in a prospective study with daily interferon therapy 5 × 106 IU s.c. for one or two years. All had the primary tumour removed at laparotomy, and whenever technically possible, an embolization of the hepatic arteries was performed prior to interferon start. Recombinant human α2b interferon from Schering-Plough was employed. When interferon was given alone, 24% responded after one year, judged from a 50% reduction in excretion of 5-hydroxyindoleacetic acid in the urine. Three patients had died. Stable disease was found in 43%, while 19% progressed. Survival rate was 40% after 5 years from start of therapy. the median survival time from start of therapy was 3 years and 4 months. When embolization of the liver arteries had been performed prior to the start of interferon treatment, the response rate was 60% after one year, 20% had stable disease and 20% progressed. Survival rate was 75% up to 5 years of observation. We conclude that interferon is an effective treatment of malignant metastatic midgut carcinoid and that survival might be prolonged compared with historical controls. Embolization of the liver arteries seems to increase the response rate after one year. Kaplan-Meier plots suggest prolonged survival when interferon treatment is combined with embolization.