Novel use of a vaginal cylinder purposed dually as obturator and localiser for stereotactic ablative radiotherapy delivery

Background:Vaginal cancer is a rare malignancy that poses a challenge to treat and cure, as surgical excision requires life-changing procedures because of the proximity and involvement of rectum, bladder and anus. We report in this case study the successful delivery of stereotactic ablative radiotherapy (SABR) for a patient with vaginal cancer after previous radiotherapy.Methods:A 71-year-old white female who presented with dyspareunia and irritative urinary symptoms proven by biopsy was our candidate patient. Subsequent PET/CT revealed a hypermetabolic 3 cm lesion at the 12–1 o’clock position in the distal vagina involving the clitoris. The patient was initially treated with volumetric-modulated arc therapy (VMAT) with simultaneous integrated boost technique to the involved nodes, and later upon recurrence treated with SABR using 30 Gy in six fractions.Findings:To our knowledge, this is the first report of a vaginal cylinder used to physically distance organs at risk from the treatment target and also as a localising device with image guidance for the delivery of SABR using an external beam.