Evaluation of Efficacy of Neoadjuvant Immunochemotherapy for Cervical Metastatic Squamous Cell Carcinoma of Unknown Primary

This study aims to evaluate the antitumor activity of neoadjuvant immunochemotherapy in patients with cervical metastatic squamous cell carcinoma of unknown primary (CMSCCUP), providing a new idea for its treatment.

We retrospectively examined the medical records from Sun Yat-sen University Cancer Center to identify patients with CMSCCUP from July 2020 to November 2023. CMSCCUP's diagnoses are based on the results of biopsy and imaging examination. All patients received PD-1 inhibitors combined with chemotherapy: paclitaxel (Albumin-bound) 260 mg/m² and cisplatin 60 mg/m² every 3 weeks for two or more cycles as their initial treatment. Clinical response after neoadjuvant immunochemotherapy was assessed using Response Evaluation Criteria in Solid Tumors (RECIST), version 1.1. Surgery, radiotherapy, or chemoradiotherapy was performed subsequently based on the imaging evaluation results. Outcomes included overall survival (OS) and disease-free survival (DFS).

After neoadjuvant immunochemotherapy, the objective response rate (ORR) was 84.2%; complete response (CR), partial response (PR), and stable disease (SD) were 36.8%, 47.4%, and 15.8%, respectively. Of the 9 patients (42.9%) who underwent surgery after neoadjuvant immunochemotherapy, 7 (77.8%) achieved pathological complete response (pCR). No severe treatment-related adverse events occurred. The most common treatment-related adverse events were Grade 1-2 fatigue (11/14, 78.6%), decreased appetite (11/15, 73.3%), and increased aspartate transaminase (12/20, 60.0%). One (1/20, 5.0%) patient experienced Grade 3 anemia. The 2-year overall survival (OS) and 2-year disease-free survival (DFS) rates were 94.4% and 89.4%, respectively.

Neoadjuvant immunochemotherapy showed favorable efficacies, anticipated outcomes, and tolerable toxicity for patients with CMSCCUP. More clinical practice and clinical studies are still needed to confirm further.