Margriet Kwint

Acute esophagus toxicity after IMRT and concurrent chemoradiation 121 6 Table 2: Spearman’s rank correlation coefficients of dose volume parameters and acute esophagus toxicity (AET). * correlation is significant at the 0.05 level; **correlation is significant at the 0.01 level Variables Correlation with AET Correlation with V50 Dmax 0.237 ** 0.536 ** Dmean 0.220 ** 0.960 ** V5 0.104 0.665 ** V10 0.135 0.727 ** V15 0.149 0.764 ** V20 0.161 0.833 ** V25 0.174 * 0.876 ** V30 0.193 * 0.909 ** V35 0.222 ** 0.944 ** V40 0.231 ** 0.970 ** V45 0.250 ** 0.991 ** V50 0.250 ** -- V55 0.265 ** 0.989 ** V60 0.284 ** 0.938 ** V65 0.300 ** 0.856 ** V70 0.247 ** 0.708 ** Table 3: Results of the backward stepwise regression analysis; Volume of the esophagus receiving ≥50 Gy (V50) to predict Acute Esophagus Toxicity grade 2 and 3 Acute Esophagus Toxicity Variable Coefficient Standard deviation of the coefficient p-value Odds ratio Grade 2 V50 0.027 0.011 0.012 1.027 Constant -0.515 0.405 0.204 0.598 Grade 3 V50 0.032 0.013 0.012 1.033 Constant -2.486 0.561 <0.001 0.083