Adjuvant vaginal cylinder brachytherapy may be recommended for early stage endometrial adenocarcinoma based on various risk factors such as age, grade, depth of myometrial invasion, tumor extent, and lymphovascular space invasion. Vaginal cylinders are available in various lengths and diameters to customize treatment based on patient anatomy. The American Brachytherapy Society recommends that the proximal 3-5 cm of vagina be treated routinely. Treatment of the entire vaginal canal can be considered for serous and clear cell histologies, grade 3 disease, or extensive lymphovascular space invasion, as these are risk factors for distal vaginal recurrence. The entire length of the vagina is not routinely treated to minimize toxicity given the generally low risk of distal vaginal recurrence. Source: Small et al. Brachytherapy 2012
When treating with a vaginal cylinder, the largest diameter vaginal cylinder that is comfortable for the patient should be used. This reduces dose to the vaginal surface due to the inverse-square law.
