A 20-year-old woman had a sporadic case of medullary
thyroid carcinoma (MTC) metastatic to the lungs. After a transient response to
streptozotocin and
doxorubicin, new subcutaneous lesions appeared on the left chest wall and there was progression of
pulmonary disease. Because MTC is one of the
amine precursor uptake and decarboxylation (APUD)
tumors, treatment was undertaken with agents active in these diseases.
Dacarbazine and
5-fluorouracil, given daily for 5 days every 4 weeks, resulted in complete resolution of pulmonary and subcutaneous lesions and a sharp decrease in
tumor marker levels that lasted 10 months. Recurrence of the
pulmonary disease lead to her death 21 months after presentation. Thus, the chemo-responsiveness of MTC may be akin to that of other APUD
carcinomas (
APUDomas) and treatment of metastatic MTC and other
APUDomas with the combination of
dacarbazine and
5-fluorouracil appears to merit further study.