INFLUENCE OF INTRALUMINAL BRACHYTHERAPY DOSE ON COMPLICATIONS IN THE TREATMENT OF ESOPHAGEAL CANCER

Purpose: Demonstration of the influence of intraluminal brachytherapy dose on complications in the treatment of esophageal carcinoma. Method s and Materials: Between January 1990 and June 1991, 75 patients with esophageal cancer were treated with external radiotherapy followed by intraluminal brachytherapy. Patients had a Karnofsky score of over 70, with no supra-clavicular nodal or distant disease. An external radiot herapy dose between 40 and 55 Gy (mean 52 Gy), 5 times a week, 2 to 2. 06 Gy/fraction, followed by a single session of Intraluminal brachythe rapy using a locally developed, manual, afterloading applicator with C s-137 sources with dose ranges of 8-10 Gy (Group 1:42 patients), 10-12 Gy (Group 2:11 patients), and 12-15 Gy (Group 3: 22 patients) at a me an dose rate of 2.09 Gy/hr was delivered. Results: The actuarial figur es at 1 year were 39% for overall survival, 29% for disease-free survi val, and 38% for local control. Fourteen patients (18.6%) developed co mplications of either an esophageal stricture or fistula. These were d ependent on intra-luminal brachytherapy dose, whereas external radioth erapy and intra-luminal brachytherapy doses did not contribute signifi cantly to local control. For Groups 1, 2, and 3, actuarial local contr ol were 28%, 45%, and 63% (p < 0.1) and of complications were 6%, 20%, and 70%, (p < 0.001), respectively. Also, on applying the Time/Dose/F ractionation formula on brachytherapy doses, it was found that the com plication rate was 6% for TDF of < 31, 25% for TDF of 32-37, and 70% f or TDF of > 38 (p < 0.001). Conclusion: External radiotherapy doses in the range of 50 to 55 Gy followed by a dose of 10-12 Gy of intralumin al brachytherapy was found optimal with respect to complications and l ocal control in the radiotherapeutic management of esophageal cancer.