Black Urine and Black Pleural Fluid: A Distinctive Presentation of Metastatic Melanoma

Abstract

Metastatic melanoma is an uncommon clinical entity which can have an unusual presentation. We describe a patient with metastatic melanoma who presented with diffuse melanosis cutis, black urine and black pleural effusion. Very few medical conditions can cause black discoloration of body fluids, so this should prompt physicians to search for a number of potential underlying causes. LEARNING POINTS• Diffuse melanosis cutis is a rare presentation of metastatic melanoma.• Malignant melanoma with thoracic metastases can cause a black pleural effusion.• Physicians should be aware of potential causes of black discoloration of body fluids. KEYWORDS Melanoma; pleural effusion; diffuse melanosis cutis; black urine. INTRODUCTIONMalignant melanoma is the most serious of the skin cancers and has shown an increasing incidence over the past 30 years

Etiology, pathological characteristics, and clinical management of black pleural effusion

“…[42] Malignancy was by The most frequently reported cancer is metastatic melanoma (50%). [13,16,17,20,23,35,38] However, BPE is also reported in primary lung malignancies. [12,15] In patients with melanoma, black discoloration is a consequence of cytoplasmic melanin production by the cancerous cells.…”

“…Two patients had bilateral, 2 had left, and only 1 had a right-sided BPE. [8,20,24,31,37] After initial drainage, recurrence of black effusion was seen in 2 patients, both with malignancy. [8,37] All 5 patients had an exudative effusion.…”

Pleural effusion as the initial manifestation of metastatic melanoma: a case report and literature review

“…Choroidal and oral malignant melanoma were also later discovered (11,12) . It may be postulated that concealment of the primary lesion caused delayed diagnosis.…”

“…There are few reports of recurrent malignant melanoma mainly presenting with pleural effusions in the literature (5)(6)(7)(8)(9)(10)(11)(12)(13)(14)(15)(16)(17)(18) (Table 1); all were con rmed by pathology.…”

“…The typical survival time of secondary metastatic melanoma ranges between 4 and 5 months, after the diagnosis (25) . Mishe'el, S. et al (12) described a patient who presented with diffuse melanosis cutis (DMC), black pleural effusion, black urine, and died 2 weeks after admission; DMC is an extremely rare manifestation of metastatic melanoma with a poor prognosis (mean survival of ~ 4 months) (26) and was reported in approximately 0.22-0.27% of the cases (27) . However, Wang, T. S. et al reported a case of complete spontaneous regression of the metastatic lesions.…”