Treatment results of high-dose-rate remote afterloading brachytherapy for cervical cancer and retrospective comparison of two regimens.

PURPOSE

To review the treatment results and complications of high-dose-rate (HDR) intracavitary brachytherapy for patients with carcinoma of the cervix in a single institute and to compare them with those of low-dose-rate (LDR) brachytherapy reported in the literature.

METHODS AND MATERIALS

Two hundred twenty patients with carcinoma of the cervix were treated by primary radiotherapy between 1991 and 1998. The median age was 63 (range 24-84). The distribution according to Federation of Gynecology and Obstetrics (FIGO) staging system was as follows: Stage IB, 11.4%; IIA, 9.1%; IIB, 50.9%; IIIA, 3.6%; IIIB, 23.2%; and IVA, 1.8%. They were treated with whole pelvic irradiation giving 40 Gy to the midplane in 20 fractions over 4 weeks. This was followed by parametrial irradiation, giving 16-20 Gy in 8-10 fractions. HDR intracavitary brachytherapy was given weekly, with a dose of 7 Gy to point A for three fractions and, starting from 1996, 6 Gy weekly for four fractions. The median overall treatment time was 50 days (range 42-73 days). The median follow-up time was 4.7 years (range 3 months to 11.1 years). Multivariate analysis was performed using the Cox regression proportional hazards model.

RESULTS

The complete remission rate after radiotherapy was 93.4% (211/226). The 5-year actuarial failure-free survival (FFS) and cancer-specific survival (CSS) rates for stage IB, IIA, IIB, IIIA, IIIB, and IVA were 87.7% and 86.6%, 85% and 85%, 67.8% and 74%, 46.9% and 54.7%, 44.8% and 50.4%, 0% and 25%, respectively. On multivariate analysis, young age (< 50) (p = 0.0054), adenocarcinoma (p = 0.0384), and stage (p = 0.0005) were found to be independent poor prognostic factors. The 5-year actuarial major complication rates (Grade 3 or above) were as follows: proctitis, 1.0%; cystitis, 0.5%; enteritis, 1.3%; and overall, 2.8%. On multivariate analysis, history of pelvic surgery was a significant prognosticator. The two HDR fractionation schedules were not a significant prognosticator in predicting disease control and complications.

CONCLUSION

Our experience in treating cervical cancer with HDR intracavitary brachytherapy is encouraging. Our treatment results and complication rates were compatible with those of the LDR series. Further studies are eagerly awaited to better define the optimal fractionation schedule for HDR brachytherapy and the schedule on how chemotherapy may be combined with it.