Oral mucosal melanoma with contrasting clinical presentations: a case series

Elias Antonio da Silva Filho; Antônio Roberto Garcia Júnior; Paulo Sérgio Souza Pina; Suzana Catanhede Orsini Machado de Souza; Camila de Barros Gallo; Fábio de Abreu Alves; Celso Augusto Lemos; Camilla Vieira Esteves

doi:10.5327/2525-5711.537

Authors

Elias Antonio da Silva Filho Department of Oral Medicine, School of Dentistry, University of São Paulo, São Paulo, Brazil. https://orcid.org/0000-0001-7070-5602
Antônio Roberto Garcia Júnior Department of Oral Medicine, School of Dentistry, University of São Paulo, São Paulo, Brazil. https://orcid.org/0000-0003-2400-8982
Paulo Sérgio Souza Pina Department of Oral Medicine, School of Dentistry, University of São Paulo, São Paulo, Brazil. https://orcid.org/0000-0001-8205-9935
Suzana Catanhede Orsini Machado de Souza Department of Oral Medicine, School of Dentistry, University of São Paulo, São Paulo, Brazil. https://orcid.org/0000-0002-9708-9608
Camila de Barros Gallo Department of Oral Medicine, School of Dentistry, University of São Paulo, São Paulo, Brazil. https://orcid.org/0000-0002-8141-6029
Fábio de Abreu Alves Department of Oral Medicine, School of Dentistry, University of São Paulo, São Paulo, Brazil. https://orcid.org/0000-0003-3372-1536
Celso Augusto Lemos Department of Oral Medicine, School of Dentistry, University of São Paulo, São Paulo, Brazil. https://orcid.org/0000-0002-3372-6719
Camilla Vieira Esteves Department of Oral Medicine, School of Dentistry, University of São Paulo, São Paulo, Brazil. https://orcid.org/0000-0001-9673-2756

DOI:

https://doi.org/10.5327/2525-5711.537

Keywords:

Oral mucosal melanoma, Oral melanoma, Pigmented oral lesions, Case series, Oral cancer

Abstract

Background: Oral mucosal melanoma (OMM) is a rare and aggressive malignancy accounting for approximately 0.2%–0.8% of all melanomas. Its heterogeneous clinical presentation and frequently asymptomatic early course may contribute to delayed recognition and diagnosis.

Case presentation: We report two cases of OMM with markedly contrasting clinical presentations. Case 1 involved a 67-year-old woman who presented with a painful pigmented gingival lesion noticed approximately two weeks before clinical evaluation. The lesion was relatively localized and was subsequently treated surgically. Case 2 involved a 51-year-old woman with a pigmented maxillary gingival lesion reportedly present for approximately 10 years before developing progressive nodular enlargement, pain, bleeding, and extensive involvement of the maxillary gingiva and hard palate. Both lesions received a histopathological diagnosis of microinvasive oral melanoma, despite their substantially different clinical extent and evolution.

Conclusion: These cases illustrate the considerable clinical heterogeneity of OMM and reinforce the importance of timely biopsy of suspicious oral pigmented lesions, particularly when changes in size, color, surface morphology, nodularity, ulceration, or bleeding are observed. They also highlight the need to interpret histopathological findings from incisional biopsies in conjunction with the overall clinical extent of the lesion.

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