Abstract
Purpose: Merkel cell carcinoma (MCC) is a rare aggressive skin malignancy, also known as neuroendocrine carcinoma of the skin, with high rates of recurrence and distant metastasis. In refractory metastatic MCC (mMCC), besides immunotherapy, chemotherapy and radiation, peptide receptor radionuclide therapy (PRRT) may be a viable option since this type of tumor can express somatostatin receptors (SSTR). Methods: We performed a comprehensive review of the literature to evaluate the efficacy of PRRT in mMCC patients. Results: 37 patients with mMCC have received PRRT (1-5 cycles) with 177Lu- and/or 90Y-labeled somatostatin analogues (cumulative activity: 1.5-30 GBq). Radiographic response was available in 19 out of 28 patients who received PRRT alone. Six (31.6%) out of 19 patients showed objective responses, from partial to complete responses, and no severe adverse events were reported. Conclusion: Our analysis supports the use of PRRT in mMCC with sufficient SSTR uptake, although the quality of the available evidence is low. Prospective studies in terms of clinical trials are already in development and have started accruing in some parts of the world.
