Placental Chorangiocarcinoma a Specific Histological Pattern of Uncertain Incidence and Clinical Impact: Systematic Review of the Literature.

Chorangiocarcinoma is a very rare and misdiagnosed placental neoplasm. The unique morphologic features of the lesion distinguish it from other trophoblastic tumors and vascular abnormalities. We present a systematic review of the literature to provide clarity on chorangiocarcinoma entity and biology. A literature search was carried out in December 2022 using the keywords "Placental chorangiocarcinoma", "Chorangioma", "Placenta", and "Throphoblast proliferation". Articles published from 1988 to 2022 were obtained from Scopus, Google Scholar, and PUBMED. In our review, we examined maternal age, gestational age at the time of delivery, parity, type of pregnancy, placental weight, ultrasound features of the placenta, macroscopic examination and tumor size, microscopic examination, immunostaining, maternal beta-human chorionic gonadotropin, fetal and maternal outcome. Eight manuscripts were detected. They are all case reports. The macroscopic characteristics of the lesions were represented by the presence of a grey-yellow-white color well-demarcated round nodule. Microscopically, all the authors described typical aspects of malignancy as a high rate of mitosis, nuclear atypia and necrotic areas. In some cases, the presence of AE1/AE3 cytoplasmic positivity, p63 nuclear staining, and beta-human chorionic gonadotropin (BHCG) were reported. A good fetal outcome was reported in all cases of newborns with normal birth weight, except one with fetal growth restriction. Maternal outcome was good in all cases except one with maternal lung metastasis three months after delivery. The clinical course has probably underestimated the real incidence of the pathology. Only greater knowledge of its histology and its clinical course will allow us to evaluate the real prevalence of the disease.