Post radiation hysterectomy in locally advanced cervical cancer: Outcomes and dosimetric impact

Firstly, to evaluate the impact of completion hysterectomy after chemoradiation and image-guided adaptive brachytherapy (IGABT) in locally advanced cervical cancer. Secondly, to assess a potential differential dose-effect relationship for the rectum and bladder according to the realization of hysterectomy.

Two cohorts of patients were identified, differing by the realization of completion hysterectomy. Inclusions were limited to FIGO stage I-II, with no para-aortic involvement. All patients received a combination of pelvic chemoradiation followed by IGABT. Their outcomes and morbidity were reviewed. Log-rank tests were used to compare survivals. Probit analyses were performed to study dose-volume effect relationships.

The two cohorts comprised 54 patients in the completion surgery group and 157 patients in the definitive radiotherapy group. They were well balanced, except for the mean follow-up, significantly longer in the post hysterectomy cohort and the use of PET-CT in the work-up, more frequent in the definitive radiotherapy cohort. Although less local relapses were reported in the hysterectomy group, the 5-year disease-free and overall survival did not differ between groups. The cumulative incidence of severe late morbidity was significantly increased in the hysterectomy cohort: 22.5% versus 6.5% at 5years (p=0.016). Dose-volume effects were observed for the bladder, with the D_2cm3 corresponding with a 10% probability of late severe morbidity urinary events (ED₁₀) of 67.8Gy and 91.9Gy in the hysterectomy and definitive radiotherapy cohorts, respectively. A D₉₀ CTV_HR of 85Gy (planning aim) corresponded with a 93.3% rate of local control in the definitive radiotherapy cohort whereas it corresponded with a 77.3% chance to have a good histologic response (complete response or microscopic residual disease) in the hysterectomy group.

No benefit from completion hysterectomy in terms of overall or disease-free survival rates was observed, which was moreover responsible for an increase of the severe late morbidity. The realization of post-radiation hysterectomy resulted in a shift of the ED₁₀ of 24.1Gy.