Utility of next-generation sequencing in the diagnosis of metastatic melanoma: A case report.

During routine dermatologic examination, a 77-year-old male was noted to have a firm blue subcutaneous nodule on his right lateral upper back. His past medical history included metastatic melanoma of unknown primary involving right and left axillary lymph nodes, treated with ipilimumab/nivolumab with complete response, and subsequent primary uveal melanoma. The subcutaneous nodule was located near his previous right axillary scar for metastatic melanoma. Excision of the nodule showed a plexiform neoplasm involving mid and deep dermis composed of spindle and epithelioid atypical cells admixed with numerous melanophages. Central necrosis was present. Immunohistochemical studies revealed the tumor cells to be diffusely positive for HMB45, with retained expression of BAP1 and p16. The tumor cells were negative for PRAME, nuclear expression of ß-catenin, LEF1, and BRAF V600E. Molecular studies demonstrated BAP1 and GNA11 somatic mutations, a profile different from that exhibited by his prior melanoma. Collectively, these data were interpreted as a metastasis from uveal melanoma and not a recurrence of his metastatic likely cutaneous melanoma after complete response to immunotherapy. This case emphasizes the importance of molecular studies for definitive diagnosis in challenging clinical situations, especially when there is discordance among histopathological, immunohistochemical, and molecular studies. Integration of clinical, histopathological, and molecular features is warranted.

Metastatic choroidal melanoma to the contralateral eye: a rare case / Melanoma de coróide metátastico para o olho contralateral: caso raro

ABSTRACT Uveal melanoma is the most common adult primary intraocular cancer. Although liver metastasis is common to the natural history of the disease, metastasis to the fellow eye is extremely rare. Here we report the case of a 59-year-old man with choroidal melanoma in his right eye who underwent enucleation at a different center. The patient was referred to our service 21 months postoperatively, complaining of decreased vision. He was found to have a new pigmented choroidal tumor in his left eye associated with liver disease. Ocular ultrasonography and liver biopsy with histopathological and immunohistochemical analysis were performed and confirmed the diagnosis. Few similar cases have been described in the literature. The differential diagnosis included primary bilateral choroidal melanoma and metastatic choroidal tumor from a primary skin melanoma.

RESUMO O melanoma uveal é o câncer intraocular primário mais frequente em adultos. Embora a metástase hepática seja comum à história natural da doença, a metástase para o outro olho é extremamente rara. Aqui relatamos o caso de um homem de 59 anos com melanoma de coroide em seu olho direito que foi submetido à enucleação em um centro diferente. O paciente foi encaminhado ao nosso serviço 21 meses após a cirurgia, com queixa de diminuição da visão. Foi encontrado um novo tumor de coróide pigmentado em seu olho esquerdo associado com doença hepática. Ultrassonografia ocular e biópsia hepática com exame histopatológico e imuno-histoquímico foram realizadas e confirmaram o diagnóstico. Poucos casos semelhantes foram descritos na literatura. O diagnóstico diferencial incluiu melanoma de coróide bilateral orimário e tumor coroidal metastático de um melanoma primário da pele.