Tongue metastasis of cutaneous melanoma: Report of two cases and literature review

Tongue metastasis of malignant melanoma: A case report and a systemic review of the literature

OBJECTIVES

The incidence of malignant melanoma, with potential for tongue metastasis, is increasing. This study presents a case of tongue metastasis of cutaneous malignant melanoma, along with a comprehensive systematic review of the cases presented in English literature. The aim is to increase clinical and pathological knowledge of these challenging cases.

MATERIALS AND METHODS

The literature search was carried out according to PRISMA guidelines by two independent researchers using four online databases: Medline, PubMed, Web of Science and Scopus.

RESULTS

Altogether 24 cases of tongue metastasis of malignant melanoma were observed (mean age 54.9 years, range 27-86 years). The average time from the primary tumour to tongue metastasis was 4.5 years. The metastatic tumour was generally indolent or mildly symptomatic. The most prevalent clinical presentation was a submucosal, non-ulcerated tumour mass, located in the tongue base or lateral surfaces. The prognosis at the time of tongue metastasis was generally poor, with a mean survival of 2.9 months.

CONCLUSION

Considering the mild symptoms, varying age of the subjects and interval from the initial diagnosis, a comprehensive anamnesis and regular oral examination should be emphasized, and metastatic malignant melanoma considered in cases of lingual tumour.

Base of tongue metastasis of cutaneous malignant melanoma with rhabdoid and neuroendocrine features: Report of a rare case and review of the literature

Metastatic malignant melanoma (MM) represents a highly aggressive cancer associated with overall poor prognosis. Various anatomic sites can be affected, including the oral cavity and the oropharynx. It may mimic other entities by assuming a variety of clinical appearances and exhibiting a plethora of microscopic variations. Herein, we present a case of a 63-year-old male with a MM metastasizing to the base of tongue, which developed 5 years after the original diagnosis and treatment of cutaneous MM of the chest and heralded its relapse; subsequently, neurological symptoms developed as a result of metastasis to the brain. Diagnostic challenges were encountered, as the tongue lesion clinically masqueraded as a pedunculated reactive lesion and microscopically displayed unusual rhabdoid and neuroendocrine features. Tumor cells expressed S-100, HMB-45, Melan-A, and SOX-10, while most cells with rhabdoid morphology were also positive for myogenin and Myo-D1. Chromogranin and synaptophysin positivity was further noticed in a subset of cells, suggestive of focal neuroendocrine differentiation. Molecular investigation revealed mutations for the BRAF V600E gene. Divergent differentiation of tumor cells may cause diagnostic pitfalls necessitating thorough immunohistochemical analysis. The presence of rhabdoid features and neuroendocrine differentiation are very uncommon, while their co-existence is extremely rare. Better characterization of such microscopic variations in MMs with evaluation of their potential biologic significance is warranted.

Primary retromolar malignant melanoma in a Latin American patient

Primary malignant melanoma of the oral mucosa is rare and has scarcely been reported in patients from Latin America. The most frequently affected sites include the palate and gingiva of the maxilla. In this report, we describe primary malignant melanoma in a Latin American patient. A 3 × 3.5-cm black tumor was observed on the upper left retromolar area. The lesion exhibited a sessile base, irregular edges, soft consistency, and pain on palpation. Immunohistochemistry staining results were positive for S100 and HMB-45; the Ki-67 index was 20%. Contrast tomography of the skull, face, abdomen, and thorax, as well as ultrasound of the liver, did not reveal metastatic lesions. The patient underwent wide surgical excision of the lesion, followed by radiotherapy; he was subsequently rehabilitated with a somato prosthesis.