Aggressive Pelvic Angiomyxoma in a Patient with Twin Pregnancy: Diagnosis, Treatment, and Clinical Complications in Light of the Literature

(1) Background: Aggressive angiomyxoma is a mesenchymal cancer that is rare during pregnancy. It is a neoplasm that relapses and infiltrates the nearest structures. Our aim is to evaluate the management and outcomes of an observed case, in light of the current literature. (2) Methods: We observed this condition at the "Maggiore della Carità" Hospital in Novara (Italy) in a patient with an initial twin pregnancy and a suspected pelvic mass. The words "angiomyxoma" and "pregnancy" were searched on the main online scientific search sources (PubMed, Google Scholar, Scopus, WES, and Embase, etc.). (3) Results: The patient underwent surgery with a complicated follow-up, but recent negative controls. We analyzed the literature about the topic and found only 24 similar clinical cases. (4) Conclusions: Considering the current literature, it is useful to assess an aggressive angiomyxoma in the differential diagnosis of soft masses in pregnant women. The treatment of choice is surgical excision, and vaginal delivery is feasible. The therapeutic decision depends on each case.