Dose fusion and efficacy evaluation of different radical radiotherapy doses for cervical cancer

The recommended external beam radiotherapy (EBRT) dose for cervical cancer is 40-50 Gy, but there is no consensus. In this study, 45-Gy and 50.4-Gy treatment groups were compared for fused doses to target tumor areas and organs at risk (OARs), clinical efficacy, and quality of life.

Seventy-nine cases receiving radical radiotherapy within the past 3 years were retrospectively analyzed. EBRT and three-dimensional brachytherapy dose fusion values were calculated for target areas and OARs using Elastix V5.0. Clinical efficacy was assessed using Response Evaluation Criteria in Solid Tumors (RECIST), adverse events using Common Terminology Criteria for Adverse Events v4.03 (CTCAE4.03), and quality of life using the European Organization for Research and Treatment of Cancer Quality of Life Questionnaire-Core 30 (EORTC QLQ-C30).

Minimum fused dose delivered to 90% of the high-risk clinical target volume (HRCTV D90) did not differ significantly between 45-Gy and 50.4-Gy groups, whereas D2cc values of rectum and bladder (OARs) were significantly lower in the 45-Gy group (both p < 0.05). Further analysis showed that these D2cc differences resulted primarily from EBRT. No grade III-IV adverse events were observed in either group during follow up. Short-term clinical efficacy, adverse events, and EORTC QLQ-C30 functional and symptom scales also did not differ significantly between groups (all p > 0.05). However, quality of life was markedly higher in the 45-Gy group (p < 0.05).

Appropriate EBRT dose reduction can reduce OAR irradiation without compromising total target area dose or clinical efficacy. Dose fusion can facilitate the judicious choice of EBRT to limit OAR exposure, reduce adverse events, and enhance the quality of life.