ABSTRACT
Background: The combined modality approach incorporating surgery, radiotherapy(RT) and chemotherapy ( CT) forms the corner-stone of management of locally advanced head and neck squamous cell carcinoma(HNSCC). Intensity modulated radiotherapy (IMRT) is an advanced RT technique where large dose of radiation could be delivered to precisely defined target volumes while reducing dose to surrounding OARs It can be delivered in sequential manner or as simultaneous integrated boost(SIB). Aim – The aim of this study was to evaluate the feasibility and toxicity of of IMRT-SIB in post-operative cases of head and neck squamous cell carcinoma (HNSCC). Methods: This was a retrospective study done on 20 patients of HNSCC who received adjuvant RT with IMRT-SIB. Data was analysed for various dosimetric parameters and toxicity profile of patients. Toxicities were recorded using RTOG acute radiation morbidity scoring criteria. Toxicities were evaluated weekly during RT and monthly up to 3 months after RT completion. Results: The median age was 40.5 years WITH 80% patients having locally advanced disease (stage III and IV). Eleven patients received concurrent cisplatin weekly. Majority (60%) of patients developed Gr 1 mucositis with maximum being grade 3 seen in 1 patient. Maximum skin toxicity that appeared was Grade 2; found in 10% patients. Xerostomia was Grade 2 in 75% patients . Sixty percent of patients experienced Grade 2 dysphagia while 15% grade 3. Seventy five percent patients were treated with dose schedule of 66/60/54 Gy in 33# while remaining with 60/54 in 30#.the dose received by organ at risk(OAR) were within normal limits in all the patients. Conclusions: IMRT with SIB can be safely delivered in post-operative squamous cell carcinoma of oral cavity with acceptable toxicity.
ABSTRACT
High grade gliomas are common intracranial tumors and adjuvant radiotherapy after maximal safe surgical resection is the cornerstone of the management. Aim: The aim of the present study was to compare the dose distribution characteristics in patients with high grade gliomas planned with Intensity-modulated radiotherapy (IMRT) and Rapid Arc (RA). Methods: Two plan sets by IMRT and RA were generated for each patient on planning Computed Tomography (CT) data sets and were then compared. Results: Total dose prescribed was 60 Gy given in biphasic manner as per Radiation Therapy Oncology Group (RTOG) guidelines guidelines. Planning Target Volume (PTV) coverage (mean values) for IMRT was found 98% and 96% for RA. Conformity Index (CI) was 1.3 for RA, 1.2 for IMRT. Homogeneity Index (HI) was found to be 1.03 for IMRT, 1.04 for RA. Dose maximum (Dmax) for the PTV was equal for IMRT and RA (106%). Conclusions: The dose to Organ at Risks (OARs) was within the acceptable limits and comparable in both the techniques, however RA augments shorter treatment time.