Palliative Systemic Treatment of Advanced Merkel Cell Carcinoma in the Pre-Immunotherapy Era: A Retrospective, Single-Center Analysis of Patients with An Orphan Neuroendocrine Malignancy

Results: MCC is a chemotherapy-sensitive tumour with an objective response rate of 63% to first-line chemotherapy. The combination of cisplatin or carboplatin with etoposide was the most frequently used regimen (n=13) with responses seen in 69% of patients. The median progression-free survival after first-line chemotherapy was 8 months. Eight patients received second line chemotherapy with gemcitabine, taxanes or vinca alkaloids with a response rate of 25%. The median overall survival since start of first line chemotherapy was 13 months. Conclusions: A considerable proportion of patients with MCC fails local treatments and requires systemic therapy. Advanced MCC is a chemotherapy-sensitive disease with high response rates. The poor overall survival achieved with chemotherapy supports the need for novel systemic strategies, such as the routine implementation of immunologic treatment approaches. Immune checkpoint modulation is complementary to chemotherapy, and should be further developed as single agent, in sequence or in combination with other biological or cytotoxic therapy.