{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,19]],"date-time":"2026-03-19T09:01:00Z","timestamp":1773910860588,"version":"3.50.1"},"reference-count":18,"publisher":"MDPI AG","issue":"2","license":[{"start":{"date-parts":[[2012,4,16]],"date-time":"2012-04-16T00:00:00Z","timestamp":1334534400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Clinics and Practice"],"abstract":"<jats:p>Although malignant melanoma (MM) and both basal cell carcinoma (BCC) and actinic keratosis (AK) are sun-induced lesions, the coexistence of these entities at the same anatomical site (collision tumour) is exceedingly rare. We report the case of a 54-year-old woman with a known history of xeroderma pigmentosum variant (XPV) who presented with 2 separate skin lesions over the middle and upper right forearm, respectively. The clinical impression was that of BCCs or squamous cell lesions. On histological examination, both specimens showed features of melanoma in situ (MIS). In the first lesion, MIS merged with and colonised a superficial and focally invasive BCC. In the second lesion, MIS merged with an AK. No separate invasive nests of malignant melanoma were seen in either specimen. The atypical melanocytes were highlighted by Melan-A and HMB-45 immunostaining, whereas the epithelial cells in both the BCC and AK stained with the pancytokeratin MNF-116. The patient had a previous history of multiple MMs and non-melanomatous skin cancers and finally developed widespread metastatic malignant melanoma, which proved fatal. The rare and interesting phenomenon of collision tumours may pose diagnostic difficulties. To our knowledge, this is the first reported simultaneous presentation of cytologically malignant collision tumours in a patient with XPV.<\/jats:p>","DOI":"10.4081\/cp.2012.e47","type":"journal-article","created":{"date-parts":[[2012,4,16]],"date-time":"2012-04-16T14:16:17Z","timestamp":1334585777000},"page":"e47","source":"Crossref","is-referenced-by-count":4,"title":["Colonisation of Basal Cell Carcinoma and Actinic Keratosis by Malignant Melanoma In Situ in a Patient with Xeroderma Pigmentosum Variant"],"prefix":"10.3390","volume":"2","author":[{"given":"Louise J.","family":"Smith","sequence":"first","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Ehab A.","family":"Husain","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2012,4,16]]},"reference":[{"key":"ref1","doi-asserted-by":"crossref","first-page":"253","DOI":"10.1097\/00000372-199406000-00005","article-title":"Cutaneous collision tumors. 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Am J Dermatopathol"},{"key":"ref5","doi-asserted-by":"crossref","first-page":"314","DOI":"10.1097\/01.dad.0000171600.17692.65","article-title":"Combined high-grade basal cell carcinoma and malignant melanoma of the skin (\u201cmalignant basomelanocytic tumor\u201d): report of two cases and review of the literature","volume":"27","author":"Rodriguez","year":"2005","journal-title":"Am J Dermatopathol"},{"key":"ref6","doi-asserted-by":"crossref","first-page":"275","DOI":"10.1111\/j.1524-4725.2010.01871.x","article-title":"Correlation among dermoscopy, confocal reflectance microscopy, and histologic features of melanoma and basal cell carcinoma collision tumor","volume":"37","author":"Salerni","year":"2011","journal-title":"Dermatol Surg"},{"key":"ref7","doi-asserted-by":"crossref","first-page":"361","DOI":"10.1038\/228361a0","article-title":"New form of molecular defect in xeroderma pigmentosum","volume":"228","author":"Jung","year":"1970","journal-title":"Nature"},{"key":"ref8","first-page":"315","article-title":"Xeroderma pigmentosum: heterogeneous syndrome and model for UV carcinogenesis","volume":"65","author":"Jung","year":"1978","journal-title":"Bull Cancer"},{"key":"ref9","doi-asserted-by":"crossref","first-page":"591","DOI":"10.1016\/0190-9622(93)70079-9","article-title":"Malignant melanoma in xeroderma pigmentosum: search for a precursor lesion","volume":"28","author":"Stern","year":"1993","journal-title":"J Am Acad Dermatol"},{"key":"ref10","doi-asserted-by":"crossref","first-page":"66","DOI":"10.1159\/000051708","article-title":"Collision of squamous-cell carcinoma with melanoma in situ in a child with xeroderma pigmentosum","volume":"203","author":"Hofer","year":"2001","journal-title":"Dermatology"},{"key":"ref11","doi-asserted-by":"crossref","first-page":"24","DOI":"10.1097\/00000372-200102000-00004","article-title":"Basal cell carcinomas are populated by melanocytes and Langerhans [correction of Langerhan's] cells","volume":"23","author":"Florell","year":"2001","journal-title":"Am J Dermatopathol"},{"key":"ref12","doi-asserted-by":"crossref","first-page":"395","DOI":"10.1097\/DAD.0b013e31812f5235","article-title":"Unusual occurrence of a melanoma with intermixed epithelial component: a true melanocarcinoma?: case report and review of epithelial differentiation in melanoma by light microscopy and immunohistochemistry","volume":"29","author":"Wen","year":"2007","journal-title":"Am J Dermatopathol"},{"key":"ref13","doi-asserted-by":"crossref","first-page":"285","DOI":"10.1016\/j.anndiagpath.2006.03.011","article-title":"An unusual case of colonic mixed adenoendocrine carcinoma: collision versus composite tumor. A case report and review of the literature","volume":"11","author":"Pecorella","year":"2007","journal-title":"Ann Diagn Pathol"},{"key":"ref14","doi-asserted-by":"crossref","first-page":"133","DOI":"10.1097\/01.pas.0000179118.76904.02","article-title":"Malignant melanoma metastatic to a basal cell carcinoma simulating the pattern of a basomelanocytic tumor","volume":"30","author":"Busam","year":"2006","journal-title":"Am J Surg Pathol"},{"key":"ref15","doi-asserted-by":"crossref","first-page":"1123","DOI":"10.1016\/j.biochi.2003.10.009","article-title":"Xeroderma pigmentosum variant and error-prone DNA polymerases","volume":"85","author":"Kannouche","year":"2003","journal-title":"Biochimie"},{"key":"ref16","doi-asserted-by":"crossref","first-page":"529","DOI":"10.1034\/j.1600-0625.2003.00124.x","article-title":"Molecular genetics of Xeroderma pigmentosum variant","volume":"12","author":"Gratchev","year":"2003","journal-title":"Exp Dermatol"},{"key":"ref17","first-page":"977","article-title":"Cutaneous malignant melanoma in association with other skin cancers","volume":"74","author":"Green","year":"1985","journal-title":"J Natl Cancer Inst"},{"key":"ref18","doi-asserted-by":"crossref","first-page":"319","DOI":"10.1097\/01.dad.0000164603.49026.6a","article-title":"A collision tumor involving Basal cell carcinoma and lentigo maligna melanoma","volume":"27","author":"Belisle","year":"2005","journal-title":"Am J Dermatopathol"}],"container-title":["Clinics and Practice"],"original-title":[],"language":"en","link":[{"URL":"http:\/\/www.clinicsandpractice.org\/index.php\/cp\/article\/viewFile\/322\/pdf","content-type":"application\/pdf","content-version":"vor","intended-application":"text-mining"},{"URL":"https:\/\/www.mdpi.com\/2039-7283\/2\/2\/e47\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2022,2,10]],"date-time":"2022-02-10T06:12:01Z","timestamp":1644473521000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/2039-7283\/2\/2\/e47"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2012,4,16]]},"references-count":18,"journal-issue":{"issue":"2","published-online":{"date-parts":[[2012,5]]}},"alternative-id":["cp.2012.e47"],"URL":"https:\/\/doi.org\/10.4081\/cp.2012.e47","relation":{},"ISSN":["2039-7283"],"issn-type":[{"value":"2039-7283","type":"electronic"}],"subject":[],"published":{"date-parts":[[2012,4,16]]}}}