Patients with locally advanced LH or intermediate and high risk OP squamous cell carcinomas have a modest 5 year survival (around 55%) with standard chemo-radiotherapy (CTRT) regimes. More accurate identification of primary target using metabolic imaging with FDG PET-CT leads to a smaller primary target volume and thereby improves therapeutic index. Our study assesses the safety and feasibility of a 16.2% dose escalation (effective BED 78.9Gy) in a FDG-PET directed target, alongside concurrent chemotherapy in locally advanced LH and poor prognosis OPC. Secondarily laryngo-oesophageal dysfunction rates and changes in voice scores at 2 years are being assessed. Histologically confirmed squamous cell cancer of LH (T3-4, N0-3 or any T stage with N2-3, M0 excluding cartilage and bony involvement) and intermediate/ high risk OPC (HPV negative with T2-T4, any N stage, M0 and HPV positive with more than 10 pack year history and N2b to N3 disease, M0) are being recruited. Randomisation is done after voice recording and swallow assessment as baseline, to either standard arm (66Gy in 30 fractions) or escalated arm (73.5Gy in 30 fractions) of radiotherapy along with concurrent weekly cisplatinum @ 40 mg/m2. FDG-PET CT SUV of 35% of baseline SUV is being delineated to identify primary boost volume. Patients are being assessed weekly during CTRT and post CTRT week 1, 2, 3, 4 and 8 for acute toxicities and at post CTRT months 3, 6, 12, 18 and 24 for late toxicities using CTCAE v 4.03. Response assessment is done clinically at 6-8 weeks post CTRT and monthly thereafter and radiological evaluation with CT/MRI at 3 months using RECIST criteria. However, for patients with more than 3 cm node at diagnosis, PET-CT scan is done if there is residual node post CTRT, to direct salvage. Thirty of the planned 100 patients have been recruited (4 screen failures). Twenty five have completed treatment. Eleven patients (Base of tongue-3, Tonsil-1, Soft palate-1, Posterior pharyngeal wall-1, Gottis-1, Supraglottis-1, Piriform sinus-3) are in standard and 14 (Base of tongue-3, Tonsil-3, Glottis-1, Supraglottis-1, Piriform sinus-5) in escalated arm. Mean dose(Gy) to OAR for swallowing and dysphagia were not significantly different in both arms (TABLE 1).Abstract 2778; Table 1StandardOropharynxEscalatedLarynx39.4236.55Sup Cons59.9251.95Mid cons61.758.36Inf cons53.0146.64Masseter R35.4630.65Masseter L35.8129.97Temporalis R10.786.06Temporalis L10.355.32LarynxSup Cons51.840.97Mid cons64.7366.11Inf cons66.6168.4Masseter R22.1423.2Masseter L25.8421.91Temporalis R3.614.45Temporalis L4.083.27HypopharynxLarynx67.363.36Sup Cons42.6342.96Mid cons65.3666.69Inf cons66.4868.79Masseter R20.2922.23Masseter L25.1822.11Temporalis R6.154.61Temporalis L7.934.93 Open table in a new tab At the time of last data monitoring review (September 2016), the study was allowed to continue.
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