ESTRO 2024 - Abstract Book

S1363

Clinical - Head & neck

ESTRO 2024

Overall, 41 patients were included in the analysis. Median age was 49 (interquartile range, IQR: 40-58) years old, and median Charlson Comorbidity Index was 3 (IQR: 2- 4.5), with all patients having a performance status of 0 or 1. Histology was keratizing in 3 cases, non-keratinizing in 34 and basaloid in the remaining 4. Stages were almost equally distributed between III and IVA according to the TNM 7th Edition. All pts received platinum-based concurrent chemotherapy and 26 patients received induction chemotherapy, as well. Median total dose was 70 Gy. Considering severe acute toxicity, the most common was hematological (8 patients, 19%), followed by dysphagia (4 cases), mucosal toxicity (2 cases) and skin toxicity (1 case). No grade 4 toxicity was reported. After a median follow up time of 44 (IQR: 29.3- 69.3) months, most patients were alive with no evidence of disease (26/41, 63%), while four patients were alive with disease. Overall, 7 patients were deceased at last follow-up: the cause was LANPC in 4 cases, and other- non-oncological causes- in 3. Considering the higher degree of toxicity registered during the course of follow-up, three patients experienced Grade 3 late toxicity. These were visual impairment, osteoradionecrosis and nasopharyngeal stenosis. At the last follow-up, none of the patients described clinically relevant toxicities.

Conclusion:

Conclusion After a median follow-up of almost four years, the mixed beam approach proves to be feasible, safe and effective in clinical setting. Further prospectively collected series are needed to confirm our results. After a median follow-up of almost four years, the mixed beam approach proves to be feasible, safe and effective in clinical setting. Further series are needed to confirm our results

Keywords: Radiotherapy, Head & Neck, Nasopharyngeal cancer

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Relationship and concordance between CT, MRI and PET for target delineation of oropharyngeal cancer

Parveen Ahlawat, Sarthak Tandon, Sandeep Purohit, Akash R Bellige, Sauharda Lohani, Gerim Prasai, Aslam Najeem, Apoorva Nayak, Munish Gairola

Rajiv Gandhi Cancer Institute and Research Centre, Radiation Oncology, New Delhi, India

Purpose/Objective:

Computed Tomography (CT) is the basic and widely used imaging modality to do target delineation for head and neck cancers. Positron Emission Tomography (PET) and Magnetic Resonance Imaging (MRI) have also gained wide popularity in delineation of target more accurately. Accurate delineation is an essential and prerequisite step so as to maximize tumour control and minimize normal tissue toxicity. The aim of this study was to compare volume of gross tumour volume (GTV) of primary tumour between CT, MRI and PET, and determine the concordance between these imaging modalities for locally advanced oropharyngeal cancers.