Pleural Involvement Due to Metastatic Melanoma: A Rare Complication and Literature Review

Malignant melanoma is an aggressive, therapy-resistant malignancy of melanocytes. Although there is an increase in the worldwide incidences of melanoma, the recent data indicates that rates are declining among those younger than 50 years of age. We present the case of a 50-year-old Hispanic gentleman with metastatic malignant pleural melanoma, with tumor cells strongly positive for Melan-A, HMB-45, and S-100. Pleural metastatic melanoma represents a rare event that has been described in a small number of patients and they are found to be associated with reduced median overall survival. Massive pleural effusion is also an unusual presentation and has been associated to impaired lymphatic drainage due to infiltrated mediastinal lymph nodes. Melanoma can emerge in sun-shielded areas. Besides ultraviolet radiation, xenobiotics such as drugs and carcinogenic environmental toxins filtered and bound to melanin, along with viruses are etiological candidates. Only a small number of pleural metastatic melanoma cases have been reported and they are found to be associated with reduced median overall survival.