Primary omental gestational choriocarcinoma ascertained by deoxyribonucleic acid polymorphism analysis

Abdominal choriocarcinoma is extremely rare. It is important to examine whether the disease is primary or metastatic and gestational or non-gestational.

A 26-year-old nulli-gravid woman underwent laparoscopy for presumed ectopic pregnancy. The uterus, ovaries and fallopian tubes surrounded by hemoperitoneum were unremarkable. A hemorrhagic 7-cm-sized tumor was identified on the greater omentum and excised. Histology was consistent with choriocarcinoma. Analysis of human leucocyte antigen (HLA) gene polymorphism on deoxyribonucleic acid (DNA) demonstrated that tumor DNA contained both HLA locus antigens of patient and of her husband. Clinical remission was achieved with six courses of chemotherapy.

To our knowledge, this is the first reported case of choriocarcinoma that occurred primarily on the omentum ascertained to be of gestational origin by DNA polymorphism analysis.