The role of interstitial brachytherapy using template in locally advanced gynecological malignancies

Brachytherapy plays a major role in the treatment of patients with carcinoma of the cervix. However, routine intracavitary brachytherapy may not be feasible or adequate to treat locally advanced disease. The purpose of this prospective study was to assess treatment outcome for patients with locally advanced gynecological malignancies treated with interstitial brachytherapy using Martinez Universal Perineal Interstitial Template (MUPIT) and to study the acute and late sequelae after treatment by this technique.

Thirty previously untreated patients with histologically confirmed carcinoma of the cervix (20 patients), vault (7 patients), and vagina (3 patients) were treated by a combination of external beam radiotherapy using megavoltage irradiation to the pelvis to a dose of 4000 to 5000 cGy followed by interstitial brachytherapy using MUPIT between June 2000 to August 2001 at Gujarat Cancer and Research Institute, Ahmedabad. Only those patients who were found unsuitable for conventional brachytherapy or in whom intracavitary radiotherapy was found to be unlikely to encompass the tumor volume were treated with interstitial template brachytherapy using MUPIT applicator and were enrolled for this study. Criteria for inclusion in this study were as follows: Hemoglobin--minimum 10 gm%; Performance Status--70% or more (Karnofsky Scale); Histopathological confirmation; FIGO Stage--IIb-IIIb (excluding frozen pelvis).

Among the 30 patients studied, 4 lost to follow-up and they were excluded from the study. With a median follow up of 9 months, local control was achieved in (20/26) 76.92% patients. The local control was better for nonbulky tumors compared to bulky tumors irrespective of stage of disease. Local control rate was better in patients with good regression of disease after EBRT. The time gap between EBRT and implant also had an impact on the outcome.

Interstitial template brachytherapy by MUPIT is a good alternative to deliver high-dose radiation in locally advanced gynecological malignancies where conventional brachytherapy application is either not feasible or unlikely to encompass tumor volume adequately. The locoregional control obtained is definitely better than external beam therapy alone and within the accepted range of complications. However, long-term follow-up is needed to comment on late morbidities.