15 Interstitial Brachytherapy in Gynaecological Cancer

Interstitial Brachytherapy in Gynaecological Cancer 431

In the initial experience reported by Martinez et al.(9), two out of 35 patients developed major complications: one necrotic rectal ulcer which required colostomy and one contracted painful bladder which necessitated urinary diversion. In the report on a total of 104 patients treated with interstitial brachytherapy, 37 of them presenting with advanced cervical cancers, Martinez et al. (28) reported four major complications. Among them, two occurred in the 37 patients treated for advanced cervical carcinomas. A tendency for complications to increase was observed when the dose of external irradiation exceeded 50 Gy. In the series reported by Gupta et al. (25) hyperthermia or prior irradiation did not appear to increase the complication rate. A dose-rate of less than 70 cGy/hour appeared to significantly increase the risk of grade 4 complications in the limit of a univariate analysis. Aristizabal et al. (29)reported their complications using a specific classification in three grades. Eighteen per cent of the patients presented with grade II and III, with 6 of the 19 patients developing vesico- or recto-vaginal fistulae while 6 other patients developed rectal stenosis, three requiring colostomies. The frequency of the complications was correlated with the geometric distribution of the radioactive sources. The loading of the obturator needles leading to high doses to the vaginal mucosa was associated with a higher incidence of complications: 64% of the patients with this source arrangement developed severe complications while only 19% of the patients presented severe side effects when the obturator needles were not loaded. In the series reported by Hughes-Davies et al.(32), late complications requiring surgical intervention were observed in 17% of locally controlled patients, with a 4% rate of fistula, 11% bladder complications and 17% bowel complications. Demanes et al. (26) reported their experience with high-dose rate interstitial brachytherapy in 62 patients. Grade 3 - 4 complications were observed in 6.5% of the patients. These complications consisted of one vesicovaginal fistula, one vaginal necrosis leading to a fatal hemorrhage, and two small bowel obstructions. In the recent Vienna series with HDR interstitial brachytherapy in 23 patients complications mainly occurred at the vagina: 9 patients with atrophy, 6 patients with significant shortening and narrowing, 2 patients with obliteration. One patient developed a ureteral stricture requiring surgery, one a malabsorption syndrome. No severe complications were seen at the rectum or bladder. In the series reported by Monk et al. (34) in an attempt to compare interstitial and intracavitary brachytherapy, the same serious complication rates were observed in the two groups, and reached 21% in each group. The most frequent complications were from digestive origin: intestinal obstruction was encountered in 4% in the interstitial group and 10% in the intracavitary group respectively. Digestive fistula occurred in 9% in the interstitial group and 3% in the intracavitary group respectively. Seven per cent of the patients in the interstitial group and 2% in the intracavitary group respectively experienced severe proctitis. Urinary complications were observed in 3% of the patients in the interstitial group and 2% in the intracavitary group respectively. 13 References 1. Green A, Jennings WA. New techniques in radium and radon therapy. J Faculty Radiol 1951; 2 : 206-33. 2. Mead KW. Methods of increasing accuracy in radon and radium implants. Med J Aust 1955; 2 : 232-5. 3. Barnes AC, Morton JL, Callendine GW. The use of radioactive cobalt in the treatment of carcinoma of the cervix. Am J Obstet Gynecol 1950; 60 : 1112-20.