A serious side effect for patients treated with radiation for pelvic malignancies where a breakdown in the tissues between the rectum and vagina. Whilst rare, it presents a significant clinical problem once established.
Radiation induced rectovaginal fistulas are an epithelium-lined communication between the rectum and vagina. As a result of radiation, tissue is damaged and decreases the vascular supply, this can lead to proctitis and subsequent ulceration of rectal wall. This ulceration can then progress to rectovaginal fistulas.r
The incidence of radiation induced rectovaginal fistulas have been reported between 0.3 to 7.6% of patients treated for gynaecological cancer.rr
Onset of fistula formation is reported to be about three years after completion of radiotherapy treatment.r
Risk factors include the total dose of radiation, volume irradiated, fractionation schedule, technique (i.e. brachytherapy or external beam RT) and previous surgery.r