ESTRO 2022 - Abstract Book

S953

Abstract book

ESTRO 2022

Materials and Methods Consecutive patients treated with primary (C-)RT for SCC of the larynx (not T1 glottic cancer), pharynx, and oral cavity from 2016 to 2019 were analyzed. In total of 395 patients. Clinical evaluation at 2 months after (C-)RT (which included clinical examination and flexible laryngoscopy), imaging reports, MDT decisions, and pathology reports were collected from patients records and the DAHANCA database. Descriptive statistics were used to evaluate patients and imaging data. Results Sixteen percent of the patients had laryngeal cancer, 77% had pharyngeal cancer, of which 51% were p16 positive oropharynx carcinoma. Seven percent of the cohort had oral cavity cancer. Clinical evaluation at 2 months after (C-)RT revealed that 74% of patients were clinically in complete remission. Of those, 5% of patients had persistent disease suspected by MRI at 3 months and proved by pathology. Twenty-two percent of patients were clinically suspicious for residual tumor at 2 months' clinical evaluation after (C-)RT. MRI found that 57% of these had suspicious/uncertain changes, and 46% of MRI suspicious changes lead to a positive biopsy. Of patients clinically suspicious for residual tumor, 22% had pathologically confirmed disease. In total there were 5%, 3%, and 0.4% of the total cohort with treatment failure at the nodal site (N), primary tumor (T), or both T and N, respectively, proved by pathology after a suspicious MRI evaluation. The 1 year follow up of those patients revealed that, for N failures 64% were disease free at 1 year after salvage treatment. While 9 %, 18%, and 9% of patients with N site failure died from the disease, died from other causes/other cancer or had a recurrence within 1 year of residual tumor diagnosis respectively. Eighty-nine percent of patients with failure at T site died from the disease within 1 year of diagnosis of the treatment failure. Conclusion Follow up with MRI after (C-)RT identified 5% of the patients with treatment failures after (C-)RT despite free clinical examination including endoscopy. Almost all early failures not suspected clinically were N failures. N failures had a better 1-year outcome than other treatment failures denoting that salvage treatment was more successful in patients with N-site failure. MRI is an effective modality to evaluate treatment response after primary curative RT of SCC of the larynx, pharynx and oral cavity. Four percent of the cohort did not undergo clinical evaluation nor MRI (e.g. died or discontinued (C-)RT). Purpose or Objective Late radiation-associated dysphagia (RAD) is defined as impaired swallowing efficiency/safety following chemoradiotherapy in head and neck cancer patients. In a RAD framework, the risk of impaired coughing may lead to lung aspiration and fatal lung infection. Although cough efficacy is a predictor of aspiration, cough investigation is minimal in patients with RAD. Acoustically, a cough sound is a superposition of turbulence noise – presumably due to the air jet passing through the glottis – and lower frequency noise – presumably generated by the airflow modulated by the vibrations of the vocal folds, false vocal cords and aryepiglottic folds. Because cough is a transient signal, existing software for speech analysis are not appropriate. The goal of our project is to develop an assessment method using acoustic features related to voluntary and reflexive coughs as biomarkers of aspiration in patients with RAD. As our methods are new, this study first focuses on healthy subjects in order to obtain reference values. Materials and Methods Forty healthy subjects produced voluntary and (induced) reflexive coughs, recorded using a throat microphone. Cough samples were analyzed with a software under development. Automatic final segmentation enables to measure the cough duration. A first method of analysis includes temporal features: the amplitude contour, the sample entropy and the kurtosis. These features report respectively the strength, the unpredictability (turbulence noise due to the air jet) and the impulsive quality (burst) of the signal. A second method of analysis consists of a spectral decomposition of the relative cough signal energy into several frequency bands (0-400Hz, 400-800Hz, 800-1600Hz, 1600Hz-3200Hz, >3200Hz). Results Results show an average duration of 0.3 sec for voluntary and reflexive coughs. The temporal analysis (Table 1) reports that reflexive coughs exhibit higher feature values for the curvature of the amplitude contour and the average and curvature of the kurtosis compared to voluntary coughs. This suggests overall higher impulsivity and higher contrast of impulsivity between onset, sustain and offset in reflexive coughs. The average and curvature of the sample entropy are also higher in reflexive coughs, suggesting overall higher flow noise and higher contrast of flow noise between onset, sustain and offset. Overall higher flow noise is confirmed by the larger weighted frequency and by the higher spectral features (Table 2) in frequency bands >800 Hz. Voluntary and reflexive coughs show comparable energy in frequencies <800Hz, suggesting comparably intense mechanical vibrations of the glottal structures. PO-1121 Acoustic analysis of voluntary and reflexive coughs in healthy subjects S. Mootassim-Billah 1 1 Jules Bordet, Radiation-Oncology, Brussels, Belgium