Value of computed tomography as outcome predictor of supraglottic squamouscell carcinoma treated by definitive radiation therapy

Purpose: To investigate the value of several CT-derived tumor parameters as predictors of local outcome of supraglottic squamous cell carcinoma treate d by definitive radiation therapy. Methods and Materials: The pretreatment CT studies of 103 patients with sup raglottic squamous cell carcinoma were reviewed for tumoral involvement of specific laryngeal anatomic subsites and extralaryngeal tumor spread. After redigitizing the films, tumor volume was calculated with the summation-of- areas technique. Mean follow-up time was 3.4 years, Actuarial statistical a nalysis of local and locoregional outcome was done for each of the covariat es; multivariate analysis was performed using Cox's proportional hazards mo del, Results: In the actuarial analysis CT-determined primary tumor volume was s ignificantly correlated with local recurrence rate (p < 0.001), Degree of i nvolvement of the paraglottic space at the level of the true vocal cord (p < 0.05) and subglottic extension (p < 0.001) were also significantly correl ated with local recurrence rate. In the multivariate analysis, only degree of involvement of the preepiglottic space (p < 0.01) and subglottic extensi on (p < 0.01) were found to be independent predictors of local recurrence. Total tumor volume was the strongest independent predictor of locoregional failure (p < 0.01), Conclusions: CT-determined tumor parameters are strong predictors of local and locoregional outcome of supraglottic carcinoma treated by definitive ir radiation, (C) 1999 Elsevier Science Inc.