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While a definitive primary site could not be established, the constellation of clinical and dermatologic findings raises consideration of melanoma-associated depigmentation, an immune phenomenon in which both melanocytes and melanoma cells are targeted. This case highlights how immune-mediated mechanisms may obscure the detection of a primary lesion. Recognition of this pattern may aid in evaluating atypical presentations and contribute to the broader understanding of immune involvement in melanoma progression.<\/jats:p>","DOI":"10.1136\/bcr-2025-269052","type":"journal-article","created":{"date-parts":[[2026,2,15]],"date-time":"2026-02-15T19:15:21Z","timestamp":1771182921000},"page":"e269052","update-policy":"https:\/\/doi.org\/10.1136\/crossmarkpolicy","source":"Crossref","is-referenced-by-count":0,"title":["Metastatic melanoma of unknown primary: an unusual dermatologic presentation"],"prefix":"10.1136","volume":"19","author":[{"ORCID":"https:\/\/orcid.org\/0009-0005-4274-8353","authenticated-orcid":false,"given":"Kali","family":"Morrissette","sequence":"first","affiliation":[{"name":"Dermatology, Duke University School of Medicine, Durham, North Carolina, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Rene","family":"Chen","sequence":"additional","affiliation":[{"name":"Dermatology, Duke University School of Medicine, Durham, North Carolina, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Sarah","family":"Cater","sequence":"additional","affiliation":[{"name":"Durham Veterans Affairs Medical Center, Durham, North Carolina, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Elizabeth","family":"Boswell","sequence":"additional","affiliation":[{"name":"Durham Veterans Affairs Medical Center, Durham, North Carolina, USA"},{"name":"Department of Pathology, Duke University Medical Center, Durham, North Carolina, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5491-6653","authenticated-orcid":false,"given":"Michelle","family":"Pavlis","sequence":"additional","affiliation":[{"name":"Durham Veterans Affairs Medical Center, Durham, North Carolina, USA"},{"name":"Department of Dermatology, Duke University Medical Center, Durham, North Carolina, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"239","published-online":{"date-parts":[[2026,2,15]]},"reference":[{"key":"2026021511151807000_19.2.e269052.1","doi-asserted-by":"publisher","DOI":"10.1016\/j.critrevonc.2010.04.007"},{"key":"2026021511151807000_19.2.e269052.2","doi-asserted-by":"publisher","DOI":"10.1002\/1097-0142(196511)18:11<1399::AID-CNCR2820181104>3.0.CO;2-R"},{"key":"2026021511151807000_19.2.e269052.3","doi-asserted-by":"publisher","DOI":"10.1093\/annonc\/mdp325"},{"key":"2026021511151807000_19.2.e269052.4","doi-asserted-by":"publisher","DOI":"10.1111\/j.1365-2559.1992.tb00988.x"},{"key":"2026021511151807000_19.2.e269052.5","first-page":"466","article-title":"Spontaneous Regression of Metastatic Malignant Melanoma of the Parotid Gland and Neck Lymph Nodes: a Case Report and a Review of the Literature","volume":"13","author":"King","year":"2001","journal-title":"Clin Oncol"},{"key":"2026021511151807000_19.2.e269052.6","doi-asserted-by":"crossref","first-page":"28","DOI":"10.1111\/ced.14328","article-title":"Reporting regression in primary cutaneous melanoma. 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