2890 - Does the Addition of Chemotherapy to Adjuvant Radiation Benefit the Survival for Patients with Adenocarcinoma of Cervix after Radical Surgery? A Single-Center Retrospective Cohort Study

Purpose/Objective(s): To investigate if the addition of chemotherapy to adjuvant radiation (RT) could yield additional survival benefit for post-operative patients with adenocarcinoma of cervix (ADC).

Materials/Methods: 261 ADC patients who received at least adjuvant radiotherapy after surgery from the Peking Union Medical College Hospital (PUMCH) between 2013 and 2023 were selected and analyzed. Patients who received adjuvant radiation alone and adjuvant chemoradiation after surgery were assigned into RT alone and concurrent chemoradiation (CCRT) group, respectively. The overall survival (OS) and Disease-free survival (DFS) between two groups were compared before and after propensity scoring matching (PSM). Univariate and multivariate cox regression analysis were conducted to identify the independent risk factors for DFS of these patients. The risk factors identified from the multivariate cox regression analysis were incorporated into the construction of Recursive partitioning risk stratification analysis (RPA). The survival outcomes were compared between RT alone and CCRT group in different RPA-derived risk groups.

Results: No significant differences between RT alone and CCRT group were observed whether before or after PSM in terms of OS and DFS. Before PSM, the 3-yr OS for RT alone and CCRT group were 89.2% (86.0%-92.4%) and 88.6% (85.7%-91.3%), respectively (P=0.4). And the 3-yr DFS for RT alone and CCRT group were 82.9% (79.1%-86.7%) and 79.7% (76.3%-83.1%), respectively (P=0.8). The 3-yr OS was 85.1% (80.9%-89.3%) and 81.2% (77.4%-85.0%) for RT alone and CCRT group, respectively (P=0.3). Also, the 3-yr DFS was 90.3% (86.8%-93.8%) and 86.2% (82.1%-90.3%) for RT alone and CCRT group, respectively (P=0.6). The pretreatment CA-125 level and depth of myometrial infiltration (DOI) were identified from the multivariate cox regression analysis to construct the RPA risk classification. Three RPA-derived risk groups (RPA I-III) with distinct survival outcomes were identified (P<0.001). Moreover, no significant differences between RT alone and CCRT group were spotted regarding DFS and OS (All P>0.05).

Conclusion: The addition of chemotherapy to adjuvant radiation didn't benefit ADC patients after surgery.