3736 - Comparative Study to Assess the Quality of Life in Patients with Oral Cavity Cancer Treated with Adjuvant Radiation Therapy: Standard Intensity Modulated Radiotherapy vs. Dysphagia Optimized Intensity

P. Singh¹, R. Saini¹, and A. Saha²; ¹AIIMS PATNA, PATNA, India, ²All india Institute of Medical Sciences, Patna, India

Purpose/Objective(s): Nearly 50% patients report dysphagia as a distressing symptom following radiation therapy for oral cancers compromising the quality of life. Dysphagia and aspiration related structures (DARS) if spared may improve the swallowing function in the oral cavity cancer patients treated with radiation therapy. Oral cavity cancer is most common cancer in males in India. Adjuvant radiation with standard IMRT (SIMRT) reduces locoregional recurrence. Dysphagia optimsed Intensity Modulated Radiotherapy (DOIMRT) is a noval technique wherein dose contraints if applied to the superior, middle pharyngeal constrictors (SMPC) and inferior pharyngeal constrictor (IPC) will help in limiting the distress related to swallowing and hence have a better quality of life. The Primary objective of this study was to compare the quality of life of oral cavity cancer patients treated with adjuvant radiation therapy by SIMRT and DOIMRT techniques measured at 6 months post radiotherapy.The secondary objective was to compare the dosimetric analysis of dysphagia and aspiration related structures (DARS) and the HR_PTV and IR_PTV coverage in SIMRT and DOIMRT techniques. Materials/Methods: Oral cavity cancer patients planned for adjuvant radiotherapy, who met the inclusion criteria and gave consent were randomized into the Standard IMRT and Dysphagia optimised IMRT technique. Dose–volume histograms (DVHs) was generated for all the DARS structures. Quality of life was assessed using the MDADI dysphagia questionnaire for swallowing as well as the EORTC QLQ C30 and EORTC H& N 35 questionnaire for overall quality of life was assessed at beginning and completion of radiation and thereafter after 6 months. Statistical analysis was done by JAMOVI software for windows. Normally distributed continuous data was expressed as mean and Standard deviation and for Independent samples T test for finding the statistical significance was used.

Results: A total of sixty patients, thirty each in the two groups were treated. Mean age was 46.5 years (SD- 9.26). The majority of the patients were male 93.3%. 90% had AJCC stage III and IV disease. 40 % of the patients had received induction chemotherapy, 36 % received concomitant chemotherapy. All patients received RT doses as prescribed. PTV D95 is not compromised in the DOIMRT arm. Mean dose to SMPC and IPC was significantly low in the DOIMRT arm as compared to SIMRT arm 56.3 (SD 5.95) versus 47.4 (SD 5.82) p value <0.01; and 53.8 (SD 9.68) 33.5 (SD 11.59) p value <0.01 respectively. The mean MDADI Global and composite scores at 6 months were significantly higher in DOIMRT arm as compared to SIMRT arm. DOIMRT reduced RT dose to the DARS and improved patient reported swallowing function compared with S-IMRT.

Conclusion: Reducing the radiation dose to the DARS structures can safely improve long- term swallowing function and quality of life of patients with oral cancers. Hence DOIMRT should be considered for oral cancer patients undergoing radiation.