Acute Toxicity in Nasopharyngeal Carcinoma Patients Treated with IMRT/VMAT

Purpose: To evaluate acute toxicity in nasopharyngeal cancer (NPC) patients treated with intensity modulatedradiotherapy (IMRT)/volumetric modulated arc therapy (VMAT) with or without cisplatin-based chemotherapy.Materials and
Methods: A total of 45 newly diagnosed, histologically proven non-metastatic NPC patients treatedwith IMRT between May 2010 and December 2012, were evaluated retrospectively, 37 planned with Eclipse and8 with Prowess Panther treatment planning system. The doses to the planning target volumes of primary tumorand involved lymph nodes, high risk region, and uninvolved regional nodal areas were 70 Gy, 60 Gy, and 54 Gyrespectively and delivered simultaneously over 33 fractions to 39 patients. Another 6 patients irradiated withsequential boost technique. Some 84.4% of patients received chemotherapy. Acute toxicities were graded accordingto the Radiation Therapy Oncology Group scoring criteria and Common Terminology Criteria for Adverse Events(CTCAE) for chemotherapy side effects.
Results: Median age was 43 years (14-79) and all patients were WHOtype II. Grade 1 mucositis and dysphagia were observed in 17 (37.8%), and 10 (22.2%) patients, respectively.The incidence of acute grade 2 mucositis and dysphagia was 55.6% and 68.9%, respectively. The most commonchemoradiotherapy related acute toxicities were nausea, leucopenia and thrombocytopenia. Grade 3 toxicity wasdetected in 13 (28.8%) cases. No grade 4 toxicity was occurred. Mean weight loss was 9%. None of the patientsrequired the insertion of percutaneous endoscopic gastrostomy for nutritional support. Radiation therapy wascompleted without interruption in all patients.
Conclusions: IMRT is a safe and effective treatment modality,and well tolerated by patients in the treatment of nasopharyngeal carcinoma. No unexpected side effects wereobserved.