{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,6]],"date-time":"2026-07-06T13:33:14Z","timestamp":1783344794940,"version":"3.54.6"},"reference-count":11,"publisher":"Termedia Sp. z.o.o.","issue":"4","content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Pol J Pathol"],"abstract":"<jats:p>Anorectal melanoma is an exceptionally rare and aggressive form of\u00a0cancer. One per cent of\u00a0anorectal malignant tumours are anorectal malignant melanomas, which are exceedingly uncommon. We report a\u00a0case of\u00a0a\u00a047-year-old woman who experienced painless rectal bleeding. On examination, an irregular lump was seen in the\u00a0posterior rectal wall, measuring 4 \u00d7 3.7 cm. Biopsies were obtained under endoscopic guidance for histomorphology and immunohistochemistry. The\u00a0biopsy examination showed nests of\u00a0tumour mass in the\u00a0lamina and muscularis mucosae. The\u00a0tumour mass was composed of\u00a0round to oval cells having enlarged nuclei, conspicuous nucleoli, and a\u00a0scant amount of\u00a0cytoplasm. No melanin pigmentation was noted in the\u00a0tumour cells. HMB-45, S-100, and vimentin were all detected by immunohistochemistry. A\u00a0definitive diagnosis of\u00a0amelanotic malignant melanoma was rendered. The\u00a0patient underwent abdominoperineal resection with a\u00a0hysterectomy and bilateral salpingo-oophorectomy. Anorectal melanoma presents with bleeding per rectum and is often misdiagnosed as internal haemorrhoids or adenocarcinoma clinically. Amelanotic melanoma, which lacks melanin pigment, is difficult to diagnose. Patients who appear with rectal bleeding should have a\u00a0malignant melanoma evaluation as a\u00a0possible differential diagnosis, and suitable diagnostic procedures, such as a\u00a0colonoscopy and a\u00a0biopsy with immunohistochemistry, should be carried out to arrive at a\u00a0conclusive diagnosis.<\/jats:p>","DOI":"10.5114\/pjp.2023.133846","type":"journal-article","created":{"date-parts":[[2024,1,4]],"date-time":"2024-01-04T03:49:00Z","timestamp":1704340140000},"page":"293-296","source":"Crossref","is-referenced-by-count":1,"title":["Primary amelanotic melanoma of\u00a0anorectum \u2013 a\u00a0rare case report with diagnostic challenge"],"prefix":"10.5114","volume":"74","author":[{"given":"Gyanendra","family":"Singh","sequence":"first","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Anurag","family":"Singh","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"3061","published-online":{"date-parts":[[2023,12,21]]},"reference":[{"key":"ref-1691604","doi-asserted-by":"crossref","unstructured":"Malaguarnera G, Madeddu R, Catania VE, et al. Anorectal mucosal melanoma. Oncotarget 2018; 9: 8785-8800.","DOI":"10.18632\/oncotarget.23835"},{"key":"ref-1691605","doi-asserted-by":"crossref","unstructured":"Paolino G, Didona D, Macri G, Calvieri S, Mercurie SR. Anorectal melanoma. In: Scott JF, Gerstenblith MR (ed.). Noncutaneous melanoma. Codon publications, Brisbane, Australia 2018, 83\u201198.","DOI":"10.15586\/codon.noncutaneousmelanoma.2018.ch6"},{"key":"ref-1691606","unstructured":"Matthews NH, Li WQ, Qureshi AA, Weinstock MA, Cho E. Epidemiology of\u00a0melanoma. In: Ward WH, Farma JM (ed.). Cutaneous melanoma etiology and therapy. Codon Publications, Brisbane, Australia 2017, 3-22."},{"key":"ref-1691607","doi-asserted-by":"crossref","unstructured":"Pham BV, Kang JH, Phan HH, Cho MS, Kim NK. Malignant melanoma of\u00a0anorectum: two case reports. Ann Coloproctol 2021; 37: 65-70.","DOI":"10.3393\/ac.2020.01.07.1"},{"key":"ref-1691608","doi-asserted-by":"crossref","unstructured":"Kothonidis K, Maassarani F, Couvreur Y, Vanhoute B, De Keuleneer R. Primary anorectal melanoma-a\u00a0rare entity: case report. J Surg Case Rep 2017; 2017: rjx060-rjx060.","DOI":"10.1093\/jscr\/rjx060"},{"key":"ref-1691609","doi-asserted-by":"crossref","unstructured":"Husain M, Rashid T, Ahmad MM, Hassan MJ. Anorectal malignant amelanotic melanoma: report of\u00a0a\u00a0rare aggressive primary tumor. J Can Res Ther 2022; 18: 249-252.","DOI":"10.4103\/jcrt.JCRT_461_20"},{"key":"ref-1691610","doi-asserted-by":"crossref","unstructured":"Kusuma MI, Sampetoding S, Ferdinandes., Faruk M.  Malignant melanoma of\u00a0anorectal: a\u00a0report of\u00a0two cases. Nusantara Med Sci J 2022; 7: 12-20.","DOI":"10.20956\/nmsj.v7i1.17951"},{"key":"ref-1691611","doi-asserted-by":"crossref","unstructured":"Kuka WP, Gatheru j, Mwanzi s, Onyango N, Rajula A. Primary rectal melanoma in an African female: a\u00a0case report. Pan Afr Med J 2022; 41: 286.","DOI":"10.11604\/pamj.2022.41.286.33128"},{"key":"ref-1691612","doi-asserted-by":"crossref","unstructured":"Latteri S, Teodoro M, Malaguarnera M, Mannino M, Curr\u00f2 G, La Greca G. Abdominal perineal resection or wilde local excision in primary anorectal malignant melanoma. Case report and review. Ann Med Surg 2017; 19: 74-77.","DOI":"10.1016\/j.amsu.2017.03.039"},{"key":"ref-1691613","doi-asserted-by":"crossref","unstructured":"Ugonabo O, Mohamed M, Ezeh E, Simmons J, Cuda J, Ghavimi S. A\u00a0rare metastatic primary rectal melanoma in a\u00a0geriatric male. J Med Cases 2022; 13: 369-373.","DOI":"10.14740\/jmc3929"},{"key":"ref-1691614","doi-asserted-by":"crossref","unstructured":"Bulut N, Dagistani S, Yilmaz B, et al. Surgical approach to anorectal melanoma with PET-CT staging: a\u00a0case report. Surg J (New York, NY) 2017; 3: e177-180.","DOI":"10.1055\/s-0037-1608902"}],"container-title":["Polish Journal of Pathology"],"original-title":[],"link":[{"URL":"https:\/\/www.polishjournalofpathology.com\/pdf-173385-136600","content-type":"application\/pdf","content-version":"vor","intended-application":"text-mining"},{"URL":"https:\/\/www.polishjournalofpathology.com\/pdf-173385-136600","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2026,6,23]],"date-time":"2026-06-23T11:04:14Z","timestamp":1782212654000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.polishjournalofpathology.com\/Primary-amelanotic-melanoma-of-anorectum-a-rare-case-report-with-diagnostic-challenge,173385,0,2.html"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2023,12,21]]},"references-count":11,"journal-issue":{"issue":"4","published-print":{"date-parts":[[2023]]}},"alternative-id":["173385"],"URL":"https:\/\/doi.org\/10.5114\/pjp.2023.133846","relation":{},"ISSN":["1233-9687","2084-9869"],"issn-type":[{"value":"1233-9687","type":"print"},{"value":"2084-9869","type":"electronic"}],"subject":[],"published":{"date-parts":[[2023,12,21]]}}}