BACKGROUND.
Merkel cell carcinoma (MCC) is a highly malignant skin neoplasm.
Regional lymph node and distant metastasis occur in 20 -52% of patients. The role of chemotherapy in the treatment of patients with this rare tumor is unclear.
METHODS. An exhaustive analysis of the literature (1980 -1995) describing chemotherapy for patients with locally advanced or metastatic MCC was performed. All available published medical records (n Ο 101 patients) were entered in a database.
In addition, data on six additional patients given chemotherapy during this time frame in Lyon, France, were included in the database.
RESULTS.
For the 107 patients, the overall objective response rate to first-line chemotherapy was 61% (61 of 101 evaluable patients). The response rate was 57 % (41 of 72) for patients with metastasis and 69% (20 of 29) for patients with locally advanced tumors. No clinical parameter was found to be correlated to response to chemotherapy. A high rate of toxic death during first-line treatment (n Ο 7.7%) was reported for these patients. The median overall survival from the date of chemotherapy initiation was 9 months for patients with metastasis and 24 months for patients with locally advanced tumors. The projected overall survival at 3 years was 17% for patients with metastasis and 35% for patients with locally advanced tumors. Progression after first-line chemotherapy was associated with significantly worse survival for patients with metastasis. Rates of response to second-line (n Ο 33) and third-line (n Ο 10) chemotherapy were 45% and 20%, respectively.
CONCLUSIONS. MCC is chemosensitive but rarely chemocurable in patients with
metastasis or locally advanced tumors. A high incidence of toxic death due to chemotherapy is reported in the literature.