An Effective Primary Treatment Using Radiotherapy in Patients with Eyelid Merkel Cell Carcinoma

Background: Merkel cell carcinoma (MCC) is a rare type of neuroendocrine tumor. Palpebral localization represents 2.5% of MCCs. Surgery is not always possible due to the localization or comorbidities of elderly patients. We hypothesized that radiotherapy (RT) alone could be a curative treatment in patients contraindicated for oncological surgery. Methods: We performed a retrospective monocentric study of patients with localized eyelid MCC treated with curative intent using curative radiotherapy. Results: Overall, 11 patients with histologically confirmed eyelid MCC were treated with curative radiotherapy. The median age was 77 years old (range: 53–94). Curative RT was decided mainly due to difficult localization and significant co-morbidities. The median lesion dose was 57 Gy (range: 47–70). Most patients had adjuvant lymph nodes irradiation with a median dose of 50 Gy (n = 9; 82%). The median follow-up was 62 months (6–152 months). None of the seven deaths were MCC-related. None of our patients relapsed during follow-up. Side effects related to radiotherapy were mild (no grade ≥ 2) and rare (n = 3, 21%). Conclusion: Our data suggest that curative radiotherapy is an effective and safe treatment for Merkel cell carcinoma of the eyelid and periocular region. Radiotherapy alone allows limiting the aesthetic and functional sequelae in elderly and comorbid patients who are contraindicated for oncological surgery.