OSCC HSCC Factors UA p value UA p value T stage T1 vs. T2-4b 0.96 0.94 T1-2 vs. T3-4b 0.18 0.36 T1-3 vs. T4a-b 0.073 0.53 N stage N0 vs. N1-3 0.87 0.51 N0-1 vs. N2a-3 0.52 0.48 N0-2a vs. N2b-3 0.78 0.39 N0-2b vs. N2c-3 0.61 0.19 N0-2c vs. N3 0.096 0.023* Induction chemotherapy (Yes vs. No) 1.00 0.326 Concurrent chemotherapy (Yes vs. No) 0.704 0.676 regimen with TPF/regimen without  TPF/none 0.92 0.11 regimen with CDDP/regimen without CDDP/none 0.89 0.055 regimen with DOC/regimen without DOC/none 0.93 0.818 Simultaneous thoracic EBRT for concurrent EC 0.29 0.15 Initial GTV 0.11 0.18 GTVRR 0.34 0.001* Initial BW 0.25 0.50 BWLR 0.66 0.034

Table 3: The correlation between the cervical body volume reduction rate and clinical factors. Abbreviations: OSCC = oropharyngeal squamous cell carcinoma, HSCC = hypopharyngeal squamous cell carcinoma. GTV = Gross tumor volume, BW = Body weight. The other abbreviations are the same as in Table 1. Note: *= statistical significance (the correlation coefficient (CC) in the Spearman rank correlation was 0.404), = low statistical significance (the CC was 0.26).