Prospective Observational Comparative Study of Response and Toxicities in Early Glottic Cancer Using Telecobalt Versus 3D-CRT.

Abstract

The study was performed with 50 patients, 24 patients in Arm A and 26 patients in Arm B. Arm A-Conventional Telecobalt RT 66Gy/33 fraction in stage T1N0M0 and stage T2N0M0 and Arm B-3D-CRT 66Gy/33 fraction in T1N0M0 and T2N0M0 used. At the end of RT, 6weeks, 3months acute and late toxicities were noted by RTOG/EORTC morbidity scoring criteria for skin reaction, dysphagia and laryngeal toxicity. Fiber optic Laryngoscopy clinical assessment criteria were used to assess response after 6weeks, 3months of treatment completion. At 6weeks of follow-up-Both Arm A and B complete response rate were 83.3% and 88.5% respectively and at 3months rate were 85.0% and 95.7% respectively. There was no superiority of results with 3D-CRT over 2DRT. At the end of RT dysphagia grade 3 toxicity seen 1 patient (4.2%) but in Arm B (total 26 patients) no grade 3 toxicity found. At the end of 6week and 3month, one patient (4.3%) had grade 3 toxicity on Arm B only at 3month. All these results are comparable. At the end of RT, one patient (3.8%) had incidentally dermatitis grade 3 toxicity in Arm B only. But all the results are comparable. On follow up, 6week and 3months, no grade 3 toxicity noted. At the end of RT, grade 3 laryngeal toxicity noted in 3 (12.5%) in Arm A and 2 (7.7%) in Arm B, not statistically significant. At 6week, grade 3 toxicity found in 3/24 (12.5%) in Arm A and 2/26 (7.7%) in Arm B, at 3months, 1/26 (4.3%) patient had incidental grade 3 toxicity only in Arm B. As conformal radiotherapy is more time consuming, less available in India and more costly than 2DRT, we can consider Conventional 2D planning for patients in India where most of people belong to low economic profile. Due to limitation in sample size and long-term follow-up further randomized studies are needed to validate the results.