Treatment of recurrent Merkel cell carcinoma: an analysis of 46 cases

This report describes the course of recurrent Merkel cell carcinoma and defines possible treatment strategies for recurrent disease as seen in a long-term multisite retrospective analysis. Merkel cell carcinoma is a highly aggressive neuroendocrine skin cancer. Surgery and radiation therapy have been demonstrated ability to control this disease; however, recurrence is common. Systemic chemotherapy has, as yet, no presently defined role in primary treatment, and few conclusions can be reached regarding optimal treatment of disease recurrence. Forty-six patients were identified over the last 15 years in a retrospective analysis of patient records from several hospitals in the San Antonio, TX area. Hospital charts as well as outpatient treatment records were reviewed. Almost all patients developing recurrent disease did so within the first 2 years after primary treatment. Patients presenting distant disease had a median survival of 12 months, faring worse than those who display local or nodal disease. For patients with nodal or local recurrence, the mean survival after combination therapy (chemotherapy, radiation +/- surgery) was 36.5 months as compared with 17.5 months for those treated with a single modality (surgery or radiation or chemotherapy). The overall survival rate for the 46 patients with recurrence was 37%. Multimodality therapy has shown the best results for recurrent Merkel cell carcinoma thus far, and should be used if tolerated by the patient. Aggressive salvage surgery for local or nodal recurrence is encouraged, because this disease has a tendency to become more destructive upon recurrence. Adjuvant radiation therapy should also be used, if the patient has not exceeded their dose limitations. Disseminated disease, whether primary or recurrent, warrants further investigation in terms of optimal treatment.