Improved survival with combination chemotherapy and external beam radiation therapy in uterine carcinosarcoma

To evaluate differences in survival and recurrence patterns in stage I-IV uterine carcinosarcoma patients treated with surgery followed by adjuvant chemotherapy alone, radiation alone, or a combination of both chemotherapy and radiation therapy.

A multicenter retrospective analysis of patients with surgically staged carcinosarcoma receiving adjuvant therapy from January 2000 to December 2019 was conducted. Inclusion criteria were patients with carcinosarcoma who had received primary surgical treatment, followed by adjuvant therapy with chemotherapy alone, radiation therapy alone, or a combination of chemoradiation. Patients were excluded for incomplete surgical staging data, adjuvant brachytherapy alone, adjuvant chemotherapy and brachytherapy without external beam radiation therapy, receipt of neoadjuvant chemotherapy and/or pre-operative pelvic radiation, and death due to non-cancer causes. Sites of recurrence were analyzed by adjuvant treatment modality using Pearson's χ² test. Progression-free and overall survival were calculated using Kaplan-Meier estimates. Multivariate analysis was performed using Cox proportional hazards model.

Of 176 evaluable patients, 27% (n=47) had stage I, 14% (n=24) stage II, 37% (n=66) stage III, and 22% (n=39) stage IV disease. Among them, 33% (n=59) received chemotherapy alone, 17% (n=29) received radiation therapy alone, and 50% (n=88) received chemoradiation. Patients with stage I disease recurred less frequently (64%) versus stage II (83%), stage III (85%), and stage IV (90%) (p<0.001). Stage I disease demonstrated improved progression-free and overall survival relative to all other stages (p<0.01). Across all stages, patients receiving chemoradiation experienced superior progression-free (p=0.01) and overall survival (p=0.05) versus single modality therapy. However, when analyzed in a stage-specific manor, stage III disease derived the greatest survival benefit from chemoradiation versus all other stages (p<0.01). On multivariant analysis, only stage and receipt of chemoradiation were independent predictors of survival.

Stage I disease demonstrated improved survival compared with other stages regardless of adjuvant treatment modality. Chemoradiation was associated with improved survival and better distant and local disease control for all stages of disease. Patients with stage III disease derived the most benefit from chemoradiation.