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A phase III, randomised, multicentre study of dysphagia optimised intensity modulated radiotherapy (Do-IMRT) versus standard intensity modulated radiotherapy (S-IMRT) in head and neck cancer.

Disease site: Head and neck cancer

Treatment modality: Radiotherapy

Status: In follow-up

Trial details

DARS is a parallel group, phase III, multicentre, randomised-controlled radiotherapy trial to determine if dysphagia optimised intensity modulated radiotherapy (Do-IMRT) compared to standard IMRT (S-IMRT) improves post radiotherapy swallowing difficulties in patients with head and neck cancer.

DARS aims to recruit 102 men and women following diagnosis and before administration of optional induction chemotherapy. Patients will receive either S-IMRT or Do-IMRT. Radiotherapy doses will be the same in both groups; however, in Do-IMRT patients, the irradiation of the pharyngeal muscles will be reduced by delivering inverse planned IMRT identifying these as organs at risk.

Unless contraindicated, patients will receive concomitant chemotherapy. Participants will be followed up after radiotherapy treatment at regular intervals for 24 months, and then annually for up to 5 years.

Further information

Chief Investigator: Professor Christopher Nutting, The Royal Marsden NHS Foundation Trust and The Institute of Cancer Research

ICR-CTSU Scientific Lead: Dr Emma Hall

Trial management contact: [email protected]

ISRCTN: 25458988

Sponsor: The Royal Marsden NHS Foundation Trust

Funding: Cancer Research UK (CRUK/14/014)

View DARS on the National Institute for Health Research website: NIHR - Be Part Of Research

Patient friendly information is available from the following link:

Cancer Research UK

Publications and presentations


Petkar I, Rooney K, Roe JWG, Patterson JM, Bernstein D, Tyler JM, Emson MA, Morden JP, Mertens K, Miles E, Beasley M, Roques T, Bhide SA, Newbold KL, Harrington KJ, Hall E, Nutting CM. DARS: a phase III randomised multicentre study of dysphagia- optimised intensity- modulated radiotherapy (Do-IMRT) versus standard intensity- modulated radiotherapy (S-IMRT) in head and neck cancer. BMC Cancer 2016 16:770. 


Nutting C, Rooney K, Foran B, Pettit L, Beasley M, Finneran L, Roe JW ,Tyler JE, Roques T, Cook A, Petkar I, Bhide SA, Srinivasan D, Boon C, De Winton E, Frogley R, Mertens K, Emson E, Hall E, on behalf of the DARS investigators. Results of a randomised phase III study of dysphagia-optimised intensity modulated radiotherapy (Do-IMRT) versus standard IMRT (S-IMRT) in head and neck cancer. Presented at ASCO 2020 Virtual Scientific Progamme, oral abstract sesson, head and neck cancer, abstract 6508. DOI 10.1200/JCO.2020.38.15_suppl.6508.

Tyler J, Bernstein D, Rooney K, Nutting C. Development of dysphagia optimised IMRT for head and neck cancer treatment in the DARS trial.  ESTRO 35 2016, Turin, Italy.

Clinical trials

Division of Clinical Studies

The division carries out or coordinates high-quality trials and translational research at both an early phase – typically to test new targeted drugs – and a later stage.