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Post-operative avoidance of radiotherapy: biomarker selection of women categorised to be in a very low risk group by IHC4+C.

Disease site: Breast cancer

Treatment modality: Radiotherapy

Status: In Follow-up

Trial details

PRIMETIME is a phase III, multicentre trial which tests whether radiotherapy can be safely avoided in patients considered to have such a low risk of local recurrence that the potential absolute gain from radiotherapy does not outweigh the established risks associated with breast radiotherapy.

PRIMETIME will use immunohistochemical biomarkers with clinical information (IHC4+C) to direct selective avoidance of breast radiotherapy. The IHC4+C algorithm will be used to risk stratify patients into a very low risk group (recommended avoidance of radiotherapy) or not (standard radiotherapy). 

Approximately 2,400 patients will be registered over four years to recruit 1,500 patients in the no radiotherapy group. All patients will be followed up for 10 years. 

Further information

Chief Investigator: Professor Charlotte Coles, The University of Cambridge

ICR-CTSU Scientific Lead: Professor Judith Bliss

Trial management contact: [email protected]

ISRCTN: 41579286

Sponsor: The Institute of Cancer Research (ICR)

Funding: Cancer Research UK

View a plain English summary from Cancer Research UK.

Publications and presentations

C.C. KirwanC.E. Coles, J. Bliss, On Behalf of the PRIMETIME Protocol Working Group; It's PRIMETIME. Postoperative Avoidance of Radiotherapy: Biomarker Selection of Women at Very Low Risk of Local Recurrence

Indrani S. Bhattacharya, Joanne S. Haviland, Lesley Turner, Hilary Stobart, Ada Balasopoulou, Liba Stones, Anna M. Kirby, Cliona C. Kirwan, Charlotte E. Coles & Judith M. Bliss on behalf of the PRIMETIME Trialists; Can patient decision aids reduce decisional conflict in a de-escalation of breast radiotherapy clinical trial? The PRIMETIME Study Within a Trial implemented using a cluster stepped-wedge trial design

PRIMETIME Newsletters

PRIMETIME Patient Newsletter June 2022

Clinical trials

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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.