Mesonephric-like adenocarcinoma presenting with malignant peritonitis and suspected to originate from the fallopian tube: A case report.

BACKGROUND

Mesonephric-like adenocarcinoma (MLA) is a rare and highly malignant disease that occurs in the uterine body or ovaries. We report a case of a MLA that was considered to have originated in the fallopian tube and presented with malignant peritonitis.

CASE SUMMARY: A 57-year-old female presented with a chief complaint of abdominal pain that began 2 months prior. Cancerous peritonitis was suspected. During exploratory laparoscopy, the right fallopian tube was found to be enlarged, with widespread disseminated lesions extending from the pelvic cavity to the upper abdomen. Histopathological examination of the peritoneal tissue obtained by biopsy showed tumor cells with a high nuclear/cellular ratio and proliferation of papillary tubular to pedunculated solid nests. Immunohistochemical testing was positive for GATA-binding protein 3, thyroid transcription factor 1, cluster of differentiation 10, and paired box protein-8, and negative for estrogen receptor, Wilms' tumor 1, and wild-type p53, leading to the diagnosis of MLA. Subsequently, debulking surgery was performed, and no macroscopic residual tumors were identified. The pathological diagnosis was right tubal carcinoma, mesonephric adenocarcinoma (International Federation of Gynecology and Obstetrics stage IIIC), and pT3cNXM0. Adjuvant chemotherapy was administered postoperatively; however, recurrence was noted, and the patient died 1 year and 6 months after the initial treatment.

CONCLUSION

MLA is a very rare disease with poor prognosis. Further studies are necessary to identify effective treatment options.