@article { author = {Buchapudi, Rekha Reddy and Manickam, Ravikumar and M R, Anil Kumar and C R, Tanvir Pasha and Chandraraj, Varatharaj and Pyakuryal, Anil and Narayanasamy, Ganesh}, title = {Physical and Radiobiological Evaluation of Accelerated Intensity Modulated Radiotherapy for Locally Advanced Head and Neck Cancer and Comparison with Short-Term Clinical Outcomes}, journal = {Asian Pacific Journal of Cancer Prevention}, volume = {20}, number = {8}, pages = {2463-2470}, year = {2019}, publisher = {West Asia Organization for Cancer Prevention (WAOCP), APOCP's West Asia Chapter.}, issn = {1513-7368}, eissn = {2476-762X}, doi = {10.31557/APJCP.2019.20.8.2463}, abstract = {Objective: The present study aims to evaluate the accelerated intensity modulated radiotherapy (IMRT) of headand neck (HandN) treatments using physical indices and radiobiological models with its clinical correlation usinghistogram analysis in radiation therapy (HART). The radiobiological evaluation in terms of tumor control probability(TCP) and normal tissue complication probability (NTCP) indices were compared with acute toxicity. Materials andMethods: A total of twenty patients with stage III and IV of HandN cases treated with accelerated IMRT using 6MVphotons were chosen for the study. Using HART software, physical indices of the IMRT plans have been defined byuniversal plan indices (UPI’s) which summarize the various recognized plan indices. The overall quality factor (QF)of a plan was determined by a linear combination of all indices in UPI set. The clinical outcomes in terms of the acutetoxicity like dysphagia and xerostomia were compared with NTCP values of the OAR calculated from HART software.Results: The mean QF and the mean Poisson TCP index was found to be 0.993±0.02 and 0.86 ±0.02 respectively. Themean JT Lyman NTCP index for bilateral parotid, constrictors, and larynx were found to be 0.23±0.14, 0.30±0.17 and0.22±0.15 respectively. The acute toxicities in terms of severity of xerostomia and dysphagia have shown a moderatecorrelation with NTCP values of bilateral parotids, constrictors, and larynx, respectively. Conclusion: The meanQF based on UPI was found to be close to unity, which correlates with being a better IMRT plan. The present studysuggested the existence of a moderate correlation between the calculated NTCP values and their respective severitiesof the organ at risk (OAR’s). Accelerated IMRT with chemotherapy is a clinically feasible option in the treatmentof locally advanced head and neck squamous cell carcinoma (HNSCC) with encouraging initial tumor response andacceptable acute toxicities.}, keywords = {head and neck,Histogram,TCP,NTCP,IMRT}, url = {https://journal.waocp.org/article_88685.html}, eprint = {https://journal.waocp.org/article_88685_ee1ea3359daa3a923fc7b837faa74e1e.pdf} }