Challenges in intracavitary brachytherapy application in anatomically variable uterus

Introduction: Cancer cervix is the 2 nd most common malignancy among Indian females with 1,23,907 new cases every year. Treatment options include radical radiotherapy wherein internal radiation plays an imperative role. Intracavitary applications in anatomically distorted uteri present a challenge and often result in sub-optimal applications. The purpose of this study is to determine the incidence of anatomically variable uterus in cancer cervix patients and the rate of intra-operative complications with Intracavitary brachytherapy (ICBT). Materials and methods: An audit of 276 biopsy-proven cancer cervix patients treated with ICBT between Jan 2019 to June 2022 was undertaken. FIGO stage I-IVA were included while metastatic and post-operative cases were excluded. All applications were done using the Modified Fletcher-Suit applicator, and planned on CT using Brachy vision 13.6.5, based on Point A. Results: 41/276 (14.9%) patients presented with anatomically variable uteri. 20/41 (48.78%) were retroverted uteri, 11/41 (26.82%) were anteflexed and 5 each (12.19%) had cervical stenosis and atrophied uteri respectively. The total number of applications performed was 120, and complications were recorded in 42 applications. There was a statistically significant correlation between the patient's age and the incidence of procedural complications, with an increased incidence of complications in the advanced age group (p-value — 0.001). Similarly, a significant correlation was found between distorted anatomy and the incidence of complications (p-value — 0.045). The higher rectal dose was observed in anteflexed uteri (p-value — 0.001) while retroverted uteri was associated with a higher bladder dose (p-value — 0.001). Conclusions: In anatomically difficult uteri, brachytherapy application is a challenge with significantly high rates of complications including perforation. Careful selection of tandem length and orientation of the uterine anatomy after the first fraction may enable better application in subsequent fractions.