Parametrial interstitial brachytherapy for advanced or recurrent pelvic malignancy: the Harvard/Stanford experience

In this study we evaluate the long-term efficacy and safety of transperineal interstitial implants for advanced pelvic malignancy. A total of 139 patients were treated at Stanford University Medical Center and the Joint Center for Radiation Therapy with transperineal template interstitial brachytherapy for locally advanced or recurrent cancers arising in the pelvic organs. Most patients received whole pelvis external beam irradiation to a median dose of 4200 cGy followed by an implant for a median duration of 48 hr to a median implant dose of 3000 cGy (range 600-6000 cGy). Complete follow-up was obtained for 91% of the patients. Median follow-up for survivors is 57 months (range, 10-173 months). The crude disease-free survival rate was 22% at 5 years. The 5-year crude local tumor control rate was 25%. No dose-response relationship could be demonstrated for tumor control or complications. There were no acute treatment-related deaths. Three late deaths were seen which were directly related to treatment. Major bowel complications requiring surgery were seen in 17% of patients without locally recurrent disease, and fistulas were reported in 4% of these patients. We conclude that template parametrial implant brachytherapy offers a modest chance of cure for women with locally advanced pelvic malignancy. However, this treatment causes significant late morbidity.