Purpose: The purpose of this study was to determine the role of interstitial brachytherapy in the management of selected primary cancers of the cervix and the vagina.
Methods: Thirty-nine previously untreated patients with histologically confirmed carcinoma of the cervix (31 patients) and of the vagina (8 patients) were treated by a combination of external beam radiotherapy and fluoroscopic-guided interstitial brachytherapy between November 1989 and May 1995 at the Ohio State University Medical Center because they were not suitable for standard intracavitary brachytherapy. Clinical indications for interstitial brachytherapy were extensive parametrial involvement in 22 patients, extensive vaginal involvement in 10, and poor vaginal anatomy in 7.
Results: With a median follow-up of 36 months (range 12-66 months), 16 patients (51%) with cervical carcinomas and 5 patients (62.5%) with vaginal carcinomas have experienced local control of their tumor. The local control was better for tumors < 4 cm in largest diameter compared to tumors > 6 cm in largest diameter. The 5-year actuarial survival was 34 and 38% for cervical and vaginal cancers, respectively. Only 1 patient experienced grade 3 complications (2.5%).
Conclusions: Interstitial brachytherapy can be safely used to treat patients unsuitable for standard intracavitary brachytherapy. When intracavitary dose distribution is expected to be suboptimal, interstitial brachytherapy is a good alternative.