Study investigates risk of dysphagia after radiotherapy treatment for head & neck cancer

Phase III results

At the 3rd International Conference on innovative approaches in Head and Neck Oncology (ICHNO), Dr Hanna Rahbek Mortensen and colleagues at hospitals and institutes in Denmark presented results from a large prospective trial, the DAHANCA 6 & 7 study. The study, conducted across the country, investigated risk factors for developing dysphagia (swallowing dysfunction), after undergoing radiotherapy treatment for a head & neck cancer. "We followed 1,476 patients with squamous cell carcinoma of the head and neck and found out the existence of factors related to the cancer itself, to the patient and to the treatment influencing the development of dysphagia," said Dr Mortensen.

Dysphagia may be acute (starting in direct association with treatment) or late (starting months to years after treatment). Risk factors for developing severe acute dysphagia were large tumours, spreading of cancer cells to the lymph nodes, swallowing problems at the time of diagnosis, 6 treatments per week and tumour location other than the vocal cords. Risk factors for developing late dysphagia were large tumours, swallowing problems at the time of diagnosis and tumour location other than the vocal cords.

83% of all head & neck cancer patients develop some kind of dysphagia, but this predictive model will have a major impact on patient quality of life.

"These results are very important," said Dr JA Langendijk from the University Medical Center of Groningen, The Netherlands. "Today, with the increasing use of intensity modulated radiotherapy (IMRT), the dose to the salivary glands is reduced resulting in lower risks on xerostomia (dry mouth). However, swallowing dysfunction is remaining an important side effect following irradiation in the head and neck region. Therefore, the identification of patients that are at highest risk for dysphagia, in particular late and persistent, is of major importance as this will help us to provide them with preventive measures", said Dr Langendijk.

Gastric tubes insertion and swallowing exercises could be prescribed and prevent malnutrition and weight loss. "This study will be very helpful to improve the quality of life of patients," noted Dr Mortensen. "Indeed, these measures at an early stage of the treatment will considerably reduce swallowing disorders".

But the results will also lead to a better treatment. "Dysphagia is a limiting factor for further intensification of head and neck radiotherapy. This is why the knowledge provided here may help us to better tailor treatments for the patients: it may allow us to increase the intensity of the treatment while maintaining their quality of life," concluded Dr Mortensen.