Metastatic Brain Adenocarcinoma and Pelvic Squamous Carcinoma Originating From Cervical Adenosquamous Carcinoma: A Case Report and Literature Review.

Background: Cervical adenosquamous carcinoma (ASC) has a poor prognosis, and brain metastasis (BM) is extremely rare. Patients with BM have a poor prognosis. At present, there is no satisfactory treatment and no standard effective treatment. In recent years, immune checkpoint inhibitors (ICIs) and surgical treatment have emerged as a promising treatment for recurrent and metastatic cervical cancer (CC).

Case: We report a 39-year-old CC patient whose cervical biopsy pathology showed adenocarcinoma with stage IIIC1r, and so underwent radical radiotherapy and chemotherapy 7 years ago. She was under a palliative enterostomy 4 years ago after intestinal perforation due to multiple recurrence of pelvic tumor. To our surprise, postoperative histopathology was squamous cell carcinoma and adenocarcinoma, ASC was confirmed. The postoperative efficacy of intravenous chemotherapy combined with immunotherapy was partial response (PR), and the efficacy of immunomaintenance therapy was progressive disease (PD). While she had gone through the recurrence of intestinal leakage 3 years ago, Pelvic exenteration (PE) was performed (postoperative histopathology squamous cell carcinoma), the postoperative effect was complete response (CR), and the patient selected regular reexamination. Isolated BM focus was developed in August 2024, and radiotherapy, chemotherapy and immunotherapy were refused after surgical treatment (postoperative histopathology adenocarcinoma). The progression-free survival (PFS) after BM is nearly one year. At present, the patient's reexamination showed no obvious abnormality.

Conclusion: We report a case of ASC, whose at the initial treatment, the cervical lesions were mainly adenocarcinoma. However, pelvic metastatic lesion was mainly squamous carcinoma and underwent chemotherapy combined with immunotherapy combined with PE. The histopathology form of BM is adenocarcinoma. The surgical treatment has achieved remarkable curative effect and survival benefit.The choice of treatment is often based on the number of metastases in the patient's clinical state, tumor size, and metastases in other organs.