HIGH-DOSE-RATE INTRACAVITARY BRACHYTHERAPY (HDR-IC) IN TREATMENT OF CERVICAL-CARCINOMA - 5-YEAR RESULTS AND IMPLICATION OF INCREASED LOW-GRADE RECTAL COMPLICATION ON INITIATION OF AN HDR-IC FRACTIONATION SCHEME

Purpose: To report the treatment results and rectal/bladder complicati ons of cervical carcinoma radically treated with high-dose-rate intrac avitary brachytherapy (HDR-IC). The current policy of using three-frac tion scheme was examined. Methods and Materials: Between November 1987 and August 1990, 173 patients with cervical carcinoma were treated wi th curative-intent radiation therapy. Whole pelvic irradiation was adm inistered with 10-MV X ray. Dose to the central cervix was 40-44 Gy in 20-22 fractions, following by pelvic wall boost 6-14 Gy in three to s even fractions with central shielding. Co-60 sources were used for HDR -IC, and 7.2 Gy was given to Point A for three applications, 1-2 weeks apart. Duration of follow-up was 5-7.8 years. Results: Twenty-eight p atients (16%) developed central-regional recurrences. Overall 5-year a ctuarial pelvic control rate was 83%. By stage, 5-year actuarial pelvi c control rates were 94%, 87%, and 72% for Stages IB + IIA, IIB + IIIA , and IIIB + IVA, respectively. Thirty-one patients (18%) developed di stant metastasis. Overall 5-year actuarial survival rate was 58%. By s tage, 5-year actuarial survival rates were 79%, 59%, and 41% for Stage s IB + IIA, IIB + IIIA, and IIIB + IVA, respectively. Sixty-six (38%) and 19 patients (11%) developed rectal and bladder complications, resp ectively. For rectal complication, the overall actuarial rate was 38% at 5 years. By grade, 5-year actuarial rectal complication rates were 24%, 15%, 4%, and 3% for Grades 1-4, respectively. Overall prevalence of rectal complications was 37% and 14% at 2 and 5 years, respectively . Prevalence of low-grade rectal complication (Grades 1 and 2) was dom inant at 2 years (30%), but declined to 8% at 5 years. Prevalence of h igh-grade, severe rectal complication (Grades 3 and 4) remained steady at 2 and 5 years (7% and 6%, respectively). Five-year actuarial bladd er complication was 9%. Five-year prevalence of bladder complication w as 2%. Conclusion: Using a three-fraction scheme, survival rate appear ed comparable with the existing results of the low-desk-rate technique . The incidence of rectal complication with this scheme remained relat ively high. The increased part of rectal complication was predominatel y low grade. This result suggested that therapeutic gain with this sch eme may not be good enough to circumvent its biologic disadvantage. Nu mbers of fractions >3 must be considered in future trials. (C) 1997 El sevier Science Inc.