Heterotopic Pregnancy Including Intrauterine Normal Gestation and Tubal Complete Hydatidiform Mole: A Case Report and Review of the Literature.

We report a rare case of heterotopic pregnancy with intrauterine normal gestation alongside tubal complete hydatidiform mole (CHM) that resulted in a viable pregnancy after removal of molar tissue. Because of their rarity and inherent complexity, such cases represent a significant challenge in diagnosis and management. A 34-year-old female in her 10th week of gestation presented with nausea, vomiting, and intermittent abdominal pain that progressively worsened. Imaging studies revealed a normal intrauterine fetus and an 11-cm heterogenous mass in the left adnexal region. The patient's serum human chorionic gonadotropin was higher than the reference range. Diagnostic laparoscopy revealed a large hemorrhagic mass involving the left adnexa that was removed completely. The mass was composed of blood clots admixed with necrotic tissue of vesicular appearance on gross inspection. Microscopic examination revealed large chorionic villi with circumferential trophoblastic proliferation and cisterns, all of which are characteristic of CHM. An implantation site was identified at the tubal fimbriae. Immunohistochemistry p57 demonstrated negative staining in the villous stromal and cytotrophoblastic cells, supporting the diagnosis of CHM. Chromosomal karyotyping and cytogenetic analysis were performed on chorionic villi samples from the intrauterine gestation and reported as normal (46, XX). The patient elected to continue the intrauterine pregnancy, delivering a healthy female infant at 39 weeks. Our case reaffirms that to successfully manage this rare yet life-threatening condition, heterotopic pregnancy should be included in the differential diagnosis for any gravid women presenting with persistent abdominal pain and/or extrauterine mass.