Metastasis to the fetoplacental unit during gestation: a scoping review

Tenazoa-Villalobos J.R.; Huertas-Burgos C.; Burgos-Muñoz S.; Aguirre-Mendoza M.; Pozo-Calle J.; Villoslada-Terrones V. · International Journal of Gynecological Cancer (2026) · DOI: 10.1016/j.ijgc.2026.105002

Resumen

Objective: This study systematically maps and synthesizes the clinical characteristics, histopathological invasion patterns, and perinatal outcomes of the mother-placenta-fetus triad in cases of maternal malignancies metastasizing to the fetoplacental unit. Methods: A scoping review was conducted in accordance with Preferred Reporting Items for Systematic Reviews and Meta-Analyses extension for Scoping Reviews guidelines and Joanna Briggs Institute methodology. Systematic searches were performed in PubMed, Embase, Scopus, Cumulative Index to Nursing and Allied Health Literature, and Web of Science for studies published from 1950 to 2026. Using the population, concept, and context framework, the review included studies involving pregnant women with malignancies confirmed by histopathology and evidence of metastatic spread to the placenta, umbilical cord, or fetus. Results: A total of 104 cases were identified. Melanoma was the most common primary malignancy (36.5%), followed by hematologic neoplasms (18.3%), breast cancer (15.4%), and lung cancer (11.5%). Placental metastasis was detected incidentally in 76.0% of cases during post-partum histopathological examination and in 20.2% prenatally. Confirmed fetal metastasis occurred in 20.2% of cases, with melanoma exhibiting the highest transmission rate, at 31.6%. A prognostic paradox was observed: despite a high maternal mortality rate of 80.8%, neonatal survival at follow-up was 68.3%. Obstetric complications were frequent and included iatrogenic prematurity (65.4%) and cesarean section (67.3%). Conclusions: Metastasis to the fetoplacental unit indicates advanced maternal disease and is associated with a poor maternal prognosis. Because most metastases are not detected before birth, universal histopathological examination of the placenta is essential in all cases of gestational cancer to inform neonatal staging and risk assessment. Fetal metastasis may manifest after birth; therefore, infants require at least 1 year of clinical surveillance.

Instituciones: Universidad Nacional Pedro Ruiz Gallo; Universidad Privada Antenor Orrego; Universidad Nacional de Cajamarca