Abstract
Introduction: In management of head and neck cancer, radiotherapy plays an integral role. IMRT is an established modality in radiotherapy which helps in better coverage of target volume and lower dose to critical structures which leads to lesser toxicity. Volume Modulated Arc Therapy (VMAT) offers a good alternative to IMRT with less treatment time and similar treatment outcome. In this study we have compared conformity, toxicity and treatment time of VMAT with IMRT in head and neck cancers.
Objective
- To determine dose, plan evaluation, (monitor units) MU, optimum target volume coverage with sparing of critical structures and overall treatment time in Head & Neck cancer using VMAT
- To review literature regarding benefit of VMAT over IMRT in head and neck cancer.
Material and Method: 60 patients of Head and Neck cancers treated with Radiotherapy using VMAT were analysed.
Result: Out of the 60 patients, 77% and 23% patients received a total dose of 70Gy and 66Gy respectively. Patients who received a total dose of 66Gy, the mean of dose receiving 95% volume was 66.5Gy. The average Monitor unit and treatment time were 993.8 and 4.2 minutes respectively. Those received 70Gy, mean of dose receiving 95% volume of PTV was 70.3Gy. Here the average Monitor unit and treatment time were 996.7 and 4.3 minutes respectively. The does received by parotid, brainstem and spinal cord were similar when compared with data available to IMRT planning.
Conclusion: VMAT provides similar conformity and toxicity as IMRT with less treatment time and less MU. This leads to a greater number of patient treatments in high volume centers.
Keywords: VMAT, Head and Neck Cancers, Treatment Time.
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Corresponding Author
Dr Abani Kanta Nanda
Senior Resident, Dept. of Radiation Oncology, A.H. Regional Cancer Centre, Cuttack, India
DOI: https://dx.doi.org/10.18535/jmscr/v8i10.17
