Chemotherapy for the carcinoid syndrome.
Patients with carcinoid syndrome usually die from carcinomatosis, rather than the pharmacological effects of the tumour. Functioning carcinoid tumours are resistant to radiotherapy. Twenty-four different cytotoxic drugs or combinations have been used to treat the carcinoid syndrome, but only actinomycin D, cyclophosphamide, 5-fluorouracil, melphalan, methotrexate, and streptozotocin have been tried as single agents in more than five patients. 5-Fluorouracil and streptozotocin were the most effective single agents, but their use in combination did not increase response rates. No drug combination was superior to single-agent therapy. Adriamycin has not been tested as a single agent, but results with it used in combination suggest it should be further evaluated. Liposome-encapsulated drugs may be tested, because of selective hepatic uptake.