In our 4-year initial clinical experience of 39 postoperative OCC patients treated with HT, we noted the incidences of grade 1 and grade 2, 3 trismus [according to the Common Terminology Criteria for Adverse Events v3.0 (CTCAE v3.0) ] appear inversely trend in time sequence with post-HT treatment (Fig. 1). These observations hint the possible of decreasing late complications of HT by better normal tissue sparing and sharper dose gradients (16-18) and responses to radiation induced trismus improved by IMRT (13, 14).