TWICE-PER-DAY FRACTIONATED HIGH VERSUS CONTINUOUS LOW-DOSE RATE INTRACAVITARY THERAPY IN THE RADICAL TREATMENT OF CERVICAL-CANCER - A NONRANDOMIZED COMPARISON OF TREATMENT RESULTS

Purpose: To compare the efficacy of two twice-per-day fractionated hig h dose rate (HDR) brachytherapies with a historical control group trea ted with low dose rate (LDR) brachytherapy for cervical cancer patient s. Methods and Materials: From 1985 to 1988, 92 patients with cancer o f the cervix were treated by remote-controlled, HDR brachytherapy, six fractions of 7 Gy per fraction (42 Gy) at point A (HDR-6). Fifty-seve n patients were treated with four fractions of 8 Gy per fraction (32 G y) at point A (HDR-4). A twice-per-day program was used for all HDR pa tients by two split courses. As a historical control, treatment result s of 259 patients treated with LDR brachytherapy (40 Gy in two split c ourses) were compared with those of the two HDR regimens, All patients received whole pelvic external irradiation, 36-45 Gy (mostly 40 Gy) b efore brachytherapy. Results: Five-year local control rates were not s ignificantly different for the three groups (HDR-6 = 82.0%, HDR-4 = 85 .5%, and LDR = 89.5%, respectively). Five-year survival rates were als o comparable (67.7%, 77.9%, and 74.1%, respectively). However, late co mplications were lower in HDR-4 than HDR-6 (11.0% vs. 25.6%). Conclusi ons: Both 5-year local control and survival rates were comparable amon g the three groups. However, HDR-4, which was more biologically equiva lent to our LDR regimen, showed fewer complications compared to HDR-6. In addition, our twice-per-day schedule shortened the hospital stay.