Definitive Radiotherapy for Primary Squamous Cell Carcinoma of the Vagina: Are High-Dose External Beam Radiotherapy and High-Dose-Rate Brachytherapy Boost the Best Treatment? Experience of Two Italian Institutes

Introduction: We assessed the clinical outcome and survival of 70 patients with primary vaginal squamous cell carcinoma undergoing radiotherapy (RT) at the Divisions of Radiotherapy, University of Pisa and ASST Cremona between January 1995 and June 2016. Methods: 58 patients received external beam RT (EBRT) to the entire vagina, para-vaginal area and pelvic nodes (total dose: 45-50.4 Gy). 29 patients (41.4%) received concomitant weekly cisplatin 40 mg/m2. 35 patients received an additional (15-36 Gy) high-dose-rate (HDR) brachytherapy (BT) boost and 13 received an additional (9-25 Gy) EBRT boost to the primary tumor site. 12 women exclusively received HDR-BT up to a total dose of (30-58 Gy). Results: Median overall survival (OS) was 85 months. A total RT dose of > 60 Gy was significantly associated with a better OS (p = 0.015). There was a trend for a better OS for patients aged < 70 years and for those undergoing EBRT to the entire vagina and pelvis plus BT boost. The most common grade 1-2 acute toxicities were diarrhea (24.1%) and cystitis (20.7%); grade 3 cystitis only occurred in 2 patients (3.4%). Conclusions: EBRT followed by BT boost seems to be the best treatment for vaginal carcinoma. The total dose of RT should be > 60 Gy.