DEFINITIVE TREATMENT OF PLANOCELLULAR OROPHARYNGEAL CARCINOMA WITH MODERATE ACCELERATION OF INTENSITY MODULATED RADIATION THERAPY WITH SIMULTANEOUS INTEGRATED BOOST

Abstract

Introduction: Intensity Modulated Radiation Therapy (IMRT) represents a new technique in the treatment of head and neck carcinomas. Oropharyngeal carcinomas are ideal target for this radiation technique, because of their anatomic localization close to critical healthy organs. Simultaneous Integrated Boost (SIB) in IMRT allows in at the same time at the same fraction delivering of different dose to different structures to irradiated volume with distribution on higher dose to the tumor and lower dose in elective irradiated regions. Moderate acceleration of IMRT-SIB allows in shorter time delivering of higher dose to planning target volume and achieving bigger tumor control. Objective: Aim of this study was to present planning technique IMRT – SIB with 95% dose coverage of volume of planning target volumes referring to primary oropharyngeal carcinoma, metastatic lymph nodes, elective region in head and neck which is irradiated and to critical organs near the tumor, achieving in the future better tumor control and fewer side effects on healthy tissues. Materials and methods: This retrospective study included 31 patients with advanced planocellular oropharyngeal cancer treated at University clinic of Radiotherapy and oncology- Skopje, with modulate acceleration of IMRT-SIB and weekly concurrent cisplatin. Results: With IMRT SIB we achieved high 95% dose coverage of the planned target volumes (PTV54 = 99,46 % and PTV66 = 98.74 %) and successfully spare the spinal cord as the most important organ at risk. Conclusion: IMRT- SIB fulfill the goal of better tumor coverage and moderate acceleration achieve dose reduction in critical healthy organs.