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La chimioradiothérapie concomitante améliore le taux de contrôle des cancers localement évolués des voies aérodigestives supérieures et la chimiothérapie de référence est actuellement le cisplatine. Ces résultats sont obtenus au prix d'une majoration des toxicités. Pour limiter les risques de toxicité, des contraintes de doses dans les organes à risque ont été établies initialement pour la radiothérapie bidimensionnelle, puis affinées pour la radiothérapie tridimensionnelle et l'irradiation conformationnelle avec modulation d'intensité (RCMI). Pour les toxicités aiguës de grade ≥ 3, les données de la littérature confirment que la chimioradiothérapie concomitante augmente significativement les risques de mucite et de dysphagie. Des contraintes appliquées sur un volume muqueux hors volume cible prévisionnel (PTV), les muscles constricteurs du pharynx et le larynx limitent cet impact négatif. Pour la toxicité tardive, la chimioradiothérapie concomitante aggrave significativement les risques de fibrose cervicale postopératoire et de perte d'audition. Pour d'autres organes à risque, il semble que la chimiothérapie concomitante potentialise les effets tardifs de la radiothérapie, même si les résultats sont moins marquants (plexus brachial, mandibule, muscles constricteurs du pharynx et glande parotide). L'impact clinique pourrait être lié à un effet différentiel plus marqué pour des doses inférieures aux contraintes habituelles et celui-ci s'effacerait lorsque ces seuils seraient dépassés comme cela semble être le cas pour les glandes parotides. En attendant d'avoir des données plus robustes, il paraît souhaitable d'appliquer le principe de délivrer la dose la plus faible possible dans les organes à risque. Concurrent chemoradiotherapy improves the outcome of locally advanced head and neck cancers and the current reference chemotherapy is cisplatin. These results are obtained at the cost of increased toxicities. To limit the risk of toxicity, organ at riskdose constraints have been established starting with 2D radiotherapy, then 3D radiotherapy and intensity-modulated radiotherapy. Regarding grade ≥ 3 acute toxicities, the scientific literature attests that concurrent chemoradiotherapy significantly increases risks of mucositis and dysphagia. Constraints applied to the oral mucosa volume excluding the planning target volume, the pharyngeal constrictor muscles and the larynx limit this adverse impact. Regarding late toxicity, concurrent chemoradiotherapy increases significantly the risk of postoperative neck fibrosis and hearing loss. However, for some organs at risk, concurrent chemotherapy appears to increase late radiation induced effect, even though the results are less marked (brachial plexus, mandible, pharyngeal constrictor muscles, parotid gland). This additional adverse impact of concomitant chemotherapy may be notable only when organs at risk receive less than their usual dose thresholds and this would be vanished when those thresholds are exceeded as seems to be the situation for the parotid glands. Until the availability of more robust data, it seems appropriate to apply the principle of delivering dose to organs at risk as low as reasonably achievable. [ABSTRACT FROM AUTHOR]

Radiation therapy is a common treatment for head and neck cancers, which uses ionizing radiation, to destroy cancerous tissue. Its purpose is the sterilization of cancer cells while sparing the best surrounding healthy tissue or organs. The objective of this study was to evaluate the effects of radiotherapy on salivary gland function in patients treated for head and neck cancer. Material and methods. A descriptive cross-sectional study was performed repeatedly in 33 patients with head and neck cancer and treated with radiotherapy department of the Aristide Le Dantec Hospital in Dakar (Senegal). Xerostomia, salivary flow unstimulated and stimulated saliva and pH were measured before (T0), during (T), and one month after radiotherapy (T1). The data were statistically analyzed and evaluated using the SPSS software. Results. The extreme age of patients was 18 and 69 years. People over 60 years old accounted for 45.5% of the population. Men constituted the majority of the sample (54.5%). For salivary secretion, before radiotherapy, no sign of xerostomia was observed in patients and salivary flow was normal in all patients. During radiotherapy all patients were already complaining of dry mouth, 19 had moderate hyposialia and 13 had severe hyposialia. Xerostomia and severe and moderate hyposialia were statistically associated with the radiation dose (p < 0.005). At T0, all patients had a neutral pH. At T1, 28/33 patients had a salivary pH below 5.5, which suggests a hyposialia. Conclusion. The orientation of new irradiation techniques of the head and neck to partially spare the salivary glands opens potential avenues of research and innovation for years to come. [ABSTRACT FROM AUTHOR]