Metastatic Melanoma in Pregnancy: Risk of Transplacental Metastases in the Infant

PURPOSE: Although metastases to the fetus via the placenta are rare, melanoma is the most common culprit. When it occurs, maternally derived melanoma metastasis in the infant is almost invariably fatal. PATIENTS AND METHODS: This article reviews current guidelines for placental evaluation in pregnant women with metastatic melanoma and presents surveillance recommendations for their infants. Comprehensive literature reviews were performed on melanoma in pregnancy and melanoma metastasis to the placenta and fetus. The use of interferon alfa in the pediatric population was also reviewed. A comprehensive search of the MEDLINE database (1966 to 2002) was performed. Articles were reviewed and additional references were obtained from the bibliographies. Translation of non-English articles was performed, and authors of previous publications were contacted. RESULTS: Eighty-seven patients with placental or fetal metastasis were identified. Twenty-seven occurrences were attributed to melanoma (31%). The fetus was affected in six of 27 melanoma patients (22%), with five of six infants dying of disease. The use of high-dose interferon alfa adjuvant therapy in pediatric patients has not been reported. CONCLUSION: The placentas of women with known or suspected metastatic melanoma should be carefully examined grossly and histologically by pathologists. With placental involvement, fetal risk of melanoma metastasis is approximately 22%. Neonates delivered with concomitant placental involvement should be considered a high-risk population. The risk-benefit ratio of adjuvant treatment for a potentially affected infant should be carefully weighed.