Clinical Study Of 42 Untreated Nasopharyngeal Carcinoma Patients For Intensity Modulated Radiation Therapy

Objective To verify the efficiency of untreated nasopharyngeal carcinoma(NPC) treated with intensity modulated radiation therapy( IMRT) and to observe the acute and late normal tissue toxicities.Methods we selected 42 untreated nasopharyngeal carcinoma patients who were treated with IMRT in the cancer center of wuhan union hospital.2 patients had stageⅠ,9 stageⅡ, 24 stageⅢ, and 5 stageⅣa ,2 stageⅣb;The prescription dose was engaged to the gross target volume(GTVnx) of nasopharyngeal to DT68～72 Gy,positive neck lymph nodes(GTVnd) to 66～70 Gy , clinical target volume 1(CTV1) to 66 Gy,and CTV2 to 58～60 Gy,the frationation was33 for all .The GTVnx ,CTV1 and upper neck were irradiated by IMRT technique. The lower neck and the supraclavicular fossae were irradiated with the conventional technique using an anterior field.IMRT technique was carried out using CMS-Xio-Release 4.2.0 planning system. Acute and late toxicities were graded according to RTOG/EORTC radiation morbidity scoring criteria.Results With a median followed-up of 15 months(range 4-36) , no patient developed any recurrence at the primary site and the neck lym- phaden .the subsidence rate of primary site and neck lymphaden was 95.2% and 97.6% ,respectively. Most of the patients had grade 1 to 2 acute and Grade 0 to 1 late toxicities , Xerostomia decreased with time in 20 evaluable patients.Conclusions Intensity modulated radiation therapy is able to improve localregion control and protect the normal tissue in the treatment of NPC.