High dose rate cobalt-60 afterloading intracavitary therapy of uterine cervical carcinomas in Srinagarind hospital - analysis of complications.

Objectives: To evaluate complications in uterine cervical cancer patients treated with teletherapy combined with high dose rate(HDR) cobalt-60 brachytherapy.

Materials And Methods: A retrospective study of uterine cervical cancer patients, stages IB-IVB (International Federation of Gynecologists and Obstetricians recommendations), treated by radiotherapy alone between April 1986 and December 1988 was conducted. The patients received teletherapy 50 Gy / 25 fractions, five fractions per week to the whole pelvis together with HDR Cobalt -60 afterloading brachytherapy of 850 cGy/ fraction weekly to point A for 2 fractions.

Results: The study subjects were 141 patients with uterine cervical cancer. The mean age was 49 years with a range of 30-78. The mean tumor size was 4.1 cms in diameter (range 1-8 cms ). Mean follow-up time was 2.9 years (range 1 month - 6.9 years). The treatments resulted in a 96.5% complete response rates but morbidity rates of grade 1 and grade 2 radiation proctitis of 27.0%, and 10.6 %. The grade 1 and grade 2 radiation cystitis were 1.4%, and 1.4 %. At the level of grade 3 radiation complications, 0.71% of radiation proctitis and 0.71% small bowel obstruction were observed. The mean onset time to develop radiation proctitis after complete treatment was 15 months with a range of 6-61 months, for radiation cystitis was 30 months (range 9 - 47 months) and for small bowel obstruction was 53 months in the one case it occurred.

Conclusion: Combined teletherapy along with high dose rate Cobalt -60 brachytherapy of 850 cGy/ fraction, weekly to point A for 2 fractions for uterine cancer demonstrated a slightly higher incidence of grade 2 radiation proctitis. Therefore, treatment using HDR-60 brachytherapy less than 850 cGy per fractionation for decreasing the grade 2 and grade 3 radiation morbidity is recommended.