A pilot study of combination therapy with interferon-alpha-2a and 5-fluorouracil in metastatic carcinoid and malignant endocrine pancreatic tumours.

Background: In view of the encouraging single agent response rates to interferon and 5-fluorouracil (5-FU) in malignant carcinoid and endocrine pancreatic tumours and the theoretical benefits of combination therapy with 5-FU and interferon in other tumours a study was designed to look at the feasibility of this combination, given for 12 months, in these tumours.

Patients And Methods: Patients were treated with 5-FU 750 mg/m2 by intravenous bolus every week and 3 Mega Units of recombinant interferon-alpha-2a subcutaneously 3 times per week increasing, as tolerated, to 6 then 9 MU. Fifteen patients were entered into the study.

Results: One patient died suddenly of an unrelated illness and is not assessed. None of the remaining 14 patients had radiological evidence of response to treatment, although 6 had stable disease lasting for 7 to 64 weeks (median 40 weeks). Two patients did have biochemical evidence of a response, i.e., a 50% reduction in baseline urinary 5HIAA for 26 and 52 weeks. Treatment toxicity was significant. Six patients stopped treatment prematurely because of either nausea and/or diarrhoea. Overall treatment duration ranged from 4 to 64 weeks (median 7.5 weeks).

Conclusion: Overall we found the treatment to be disappointing in terms of tolerance and response rate and do not recommend its use in malignant carcinoid or endocrine pancreatic tumours.