Background and aims: Vaginal intraepithelial neoplasia (VAIN) is an uncommon premalignant condition which can be difficult to eradicate. In view of the low incidence worldwide and lack of published work available there is no gold standard treatment. The aim of this study was to assess the outcome of VAIN 3 treated by brachytherapy at a single institution over a 20-year period.
Methods: A retrospective review of medical records was performed 1985-2004 inclusive based on hospital admissions with an ICD-9/10 diagnosis of VAIN.
Results: 22 patients with pathologically confirmed VAIN3 were treated with intracavitary brachytherapy over this time period. Median age at time of treatment was 56 years (range 37-70) and median follow up was 77 months. The majority of patients were post-menopausal smokers who presented asymptomatically following hysterectomy for cervical dysplasia/neoplasia. Medium dose rate Selectron was the method of choice, typically 48 Gy prescribed to point Z (located 0.5 cm lateral to ovoid surface) over two insertions 1 week apart. Acute toxicity was minimal. There were 5 cases of RTOG G3 toxicity, predominantly stenosis of the vagina, and 1 case of G4 toxicity resulting in vaginal ulceration. Recurrent/residual VAIN3 was documented in three patients; one of whom was successfully treated by laser ablation while the other two went on to develop invasive or micro-invasive vaginal carcinoma. The first remained disease free 17 years later following external beam radiotherapy but the second died of peri-operative complications as a consequence of radical surgery. Late progression was documented in one patient 14 years after initial treatment and was suspected in a further patient who succumbed to metastatic squamous cell carcinoma of uncertain origin 8 years later.
Conclusions: Medium dose rate brachytherapy is a well tolerated form of treatment for VAIN3 but patients must be counseled regarding potential toxicity. Long-term follow up is advised due to risk of late recurrence and second malignancy.