{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,6,15]],"date-time":"2026-06-15T06:53:17Z","timestamp":1781506397723,"version":"3.54.1"},"reference-count":27,"publisher":"MDPI AG","issue":"2","license":[{"start":{"date-parts":[[2026,6,12]],"date-time":"2026-06-12T00:00:00Z","timestamp":1781222400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Medical Sciences"],"abstract":"<jats:p>Background: Merkel cell carcinoma (MCC) is an aggressive cutaneous neuroendocrine malignancy with a high risk of recurrence. While adjuvant radiotherapy is standard following surgical resection in high-risk disease, the additional benefit of platinum\u2013etoposide chemotherapy and the prognostic role of tumor anatomical location remain uncertain. Methods: We conducted a multicenter retrospective cohort study including patients with high-risk MCC (stage IIB\u2013III) treated with surgery followed by adjuvant radiotherapy with or without platinum\u2013etoposide chemotherapy. Tumor sites were classified according to sun-exposure status. Disease-free survival (DFS) and overall survival (OS) were estimated using Kaplan\u2013Meier methods and compared using the log-rank test, with subgroup analyses by anatomical region and stage. Results: A total of 103 patients were included, of whom 77 (74.8%) received adjuvant chemoradiotherapy and 26 (25.2%) received radiotherapy alone. Patients with non-sun-exposed tumors demonstrated longer survival outcomes than those with sun-exposed tumors, with a median DFS of 57 months versus 42 months (p = 0.15), and a median OS of 179 months versus 109 months (p = 0.054), respectively. Among patients with sun-exposed tumors, chemoradiotherapy was associated with numerically improved DFS (42 vs. 34 months; p = 0.051) and OS (128 vs. 98 months; p = 0.08) compared with radiotherapy alone. In patients with non-sun-exposed tumors, chemoradiotherapy demonstrated a more pronounced improvement in OS (178 vs. 56 months; p = 0.054), while DFS also favored combined treatment (49 vs. 78 months; p = 0.078). Conclusions: In this multicenter cohort, adjuvant chemotherapy did not demonstrate a uniform survival benefit overall but was associated with improved outcomes in head and neck MCC, suggesting a potential site-specific effect. Similar outcomes across stage III subgroups suggest that chemotherapy may mitigate stage-related prognostic differences. These findings support a selective approach to adjuvant chemotherapy and highlight the need for prospective studies incorporating modern immunotherapy strategies.<\/jats:p>","DOI":"10.3390\/medsci14020311","type":"journal-article","created":{"date-parts":[[2026,6,15]],"date-time":"2026-06-15T05:59:47Z","timestamp":1781503187000},"page":"311","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Evaluating the Role of Chemotherapy in Addition to Radiotherapy for High-Risk Merkel Cell Carcinoma"],"prefix":"10.3390","volume":"14","author":[{"given":"Ronen","family":"Brenner","sequence":"first","affiliation":[{"name":"Oncology Institute, Edith Wolfson Medical Center, Holon 58220, Israel"},{"name":"Faculty of Medicine, Tel Aviv University, Tel Aviv 69978, Israel"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Hanna T.","family":"Frumin Edri","sequence":"additional","affiliation":[{"name":"Oncology Institute, Edith Wolfson Medical Center, Holon 58220, Israel"},{"name":"Faculty of Medicine, Tel Aviv University, Tel Aviv 69978, Israel"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Amichay","family":"Meirovitz","sequence":"additional","affiliation":[{"name":"The Legacy Heritage Cancer Center and Dr. Larry Norton Institute, Soroka Medical Center, Beer Sheva 84105, Israel"},{"name":"Faculty of Health Sciences, Ben Gurion University of the Negev, Beer Sheva 84105, Israel"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Sabri","family":"El-Saied","sequence":"additional","affiliation":[{"name":"Faculty of Health Sciences, Ben Gurion University of the Negev, Beer Sheva 84105, Israel"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8273-4723","authenticated-orcid":false,"given":"Keren","family":"Rouvinov","sequence":"additional","affiliation":[{"name":"The Legacy Heritage Cancer Center and Dr. Larry Norton Institute, Soroka Medical Center, Beer Sheva 84105, Israel"},{"name":"Faculty of Health Sciences, Ben Gurion University of the Negev, Beer Sheva 84105, Israel"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ilia","family":"Berezhnov","sequence":"additional","affiliation":[{"name":"Oncology Institute, Edith Wolfson Medical Center, Holon 58220, Israel"},{"name":"Faculty of Medicine, Tel Aviv University, Tel Aviv 69978, Israel"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Anna","family":"Ievko","sequence":"additional","affiliation":[{"name":"Oncology Institute, Edith Wolfson Medical Center, Holon 58220, Israel"},{"name":"Faculty of Medicine, Tel Aviv University, Tel Aviv 69978, Israel"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Sofiia","family":"Turaieva","sequence":"additional","affiliation":[{"name":"Oncology Institute, Edith Wolfson Medical Center, Holon 58220, Israel"},{"name":"Faculty of Medicine, Tel Aviv University, Tel Aviv 69978, Israel"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Shlomit","family":"Fenig","sequence":"additional","affiliation":[{"name":"Institute of Oncology, Kaplan Medical Center, Faculty of Medicine, Hebrew University, Jerusalem 91905, Israel"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Nashat Abu","family":"Yasin","sequence":"additional","affiliation":[{"name":"The Legacy Heritage Cancer Center and Dr. Larry Norton Institute, Soroka Medical Center, Beer Sheva 84105, Israel"},{"name":"Faculty of Health Sciences, Ben Gurion University of the Negev, Beer Sheva 84105, Israel"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Eyal","family":"Fenig","sequence":"additional","affiliation":[{"name":"Institute of Oncology, Davidoff Center, Rabin Medical Center, Beilinson Hospital, Petah Tikva 49414, Israel"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Samer","family":"Hussany","sequence":"additional","affiliation":[{"name":"The Legacy Heritage Cancer Center and Dr. Larry Norton Institute, Soroka Medical Center, Beer Sheva 84105, Israel"},{"name":"Faculty of Health Sciences, Ben Gurion University of the Negev, Beer Sheva 84105, Israel"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Noa Shani","family":"Shrem","sequence":"additional","affiliation":[{"name":"The Legacy Heritage Cancer Center and Dr. Larry Norton Institute, Soroka Medical Center, Beer Sheva 84105, Israel"},{"name":"Faculty of Health Sciences, Ben Gurion University of the Negev, Beer Sheva 84105, Israel"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Alexander","family":"Yakobson","sequence":"additional","affiliation":[{"name":"The Legacy Heritage Cancer Center and Dr. Larry Norton Institute, Soroka Medical Center, Beer Sheva 84105, Israel"},{"name":"Faculty of Health Sciences, Ben Gurion University of the Negev, Beer Sheva 84105, Israel"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7570-4550","authenticated-orcid":false,"given":"Walid","family":"Shalata","sequence":"additional","affiliation":[{"name":"The Legacy Heritage Cancer Center and Dr. Larry Norton Institute, Soroka Medical Center, Beer Sheva 84105, Israel"},{"name":"Faculty of Health Sciences, Ben Gurion University of the Negev, Beer Sheva 84105, Israel"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2026,6,12]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"17077","DOI":"10.1038\/nrdp.2017.77","article-title":"Merkel cell carcinoma","volume":"3","author":"Becker","year":"2017","journal-title":"Nat. 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Cancer"}],"container-title":["Medical Sciences"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/2076-3271\/14\/2\/311\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2026,6,15]],"date-time":"2026-06-15T06:19:41Z","timestamp":1781504381000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/2076-3271\/14\/2\/311"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2026,6,12]]},"references-count":27,"journal-issue":{"issue":"2","published-online":{"date-parts":[[2026,6]]}},"alternative-id":["medsci14020311"],"URL":"https:\/\/doi.org\/10.3390\/medsci14020311","relation":{},"ISSN":["2076-3271"],"issn-type":[{"value":"2076-3271","type":"electronic"}],"subject":[],"published":{"date-parts":[[2026,6,12]]}}}