Introduction: We describe an unusual case of metastatic melanoma of the brain with an unknown primary site during pregnancy.
Case Description: A 35-year-old woman in the third trimester of pregnancy presented with ataxia, nausea, vomiting, headaches and diplopia. CT of the brain revealed a hyper-attenuating 2.1 cm mass in the fourth ventricle with mild obstructive hydrocephalus. A healthy newborn was delivered by urgent caesarean section. Craniotomy and resection of the brain lesion confirmed melanoma. Pathology of the placenta reported a ‘focal nest of melanocytes identified in intervillous space’.
Discussion: Brain and maternal placenta pathology findings were consistent with melanoma, making this case relevant because of the possibility of metastatic melanoma in a fetus.
Conclusion: Epidemiological data on congenital and infantile melanoma are scarce. Also, there is no database for long-term follow-up of children born to pregnant mothers with metastatic melanoma. Delayed presentation of melanoma in the child cannot be ruled out.