PRIMETIME – Post-operative avoidance of radiotherapy in minimal risk women: patient selection using biomarkers

Not Applicable

• Conditions: Breast cancer; Cancer; Malignant neoplasm of breast

• Registration Number: ISRCTN41579286
• Lead Sponsor: Institute of Cancer Research

Brief Summary

2021 Interim results article in https://pubmed.ncbi.nlm.nih.gov/34127033/ (added 13/08/2021)

Detailed Description

Not available

Study Timeline

• Results First Posted: 1900-01-01
• Study Start: 2017-03-07
• Last Update Posted: 20 November 2023
• Study Completion: 2030-05-19

Recruitment & Eligibility

• Status: Ongoing
• Sex: Female
• Target Recruitment: 2400

Inclusion Criteria

1. Provision of written informed consent to participate in the PRIMETIME study
2. Provision of slides for research testing and availability of KI67 result (contact ICR-CTSU to confirm)
3. Women aged =60 years (younger patients are eligible if they are post-menopausal and have co-morbidities that imply a high risk of radiotherapy toxicity e.g. significant cardiovascular disease with left sided breast cancer)
4. Women having had breast conserving surgery with complete resection of tumour tissue (=1 mm microscopic, circumferential margins of normal tissue from invasive cancer and DCIS)
5. AJCC staging of pT1/pN0/M0 (DCIS is allowed in combination with invasive breast cancer; isolated tumour cells in axillary nodes are allowed)
6. Histological confirmation of grade 1 or 2 invasive breast cancer
7. Oestrogen receptor (ER) positive according to local practice. The H score must be available.
8. Progesterone receptor (PR) positive according to local practice. The percentage positivity must be available.
9. Human epidermal growth factor receptor (HER2) negative according to local practice
10. Patients must be recommended for =5 years adjuvant endocrine therapy according to local policy and in the investigator’s opinion, deemed able to comply with the duration of treatment

Exclusion Criteria

1. Patients known to have lymphovascular space invasion and/or axillary nodal micrometastases or macrometastases.
2. Patients with a past history of malignancy excep:
2.1. Basal cell skin cancer and CIN cervix uteri
2.2.Treated, localised squamous cell carcinoma of the skin
2.3. Malignancies treated with curative intent and the patient has been disease free =5 years
3. Patients who have had an ipsilateral mastectomy
4. Patients who have received neoadjuvant therapy (endocrine or cytotoxic chemotherapy with therapeutic intent) or who are deemed by the MDT to require adjuvant cytotoxic chemotherapy
5. Patients with mammographically occult breast cancers, ie. present with lump, but not visible on mammogram

Study & Design

• Study Type: Interventional
• Study Design: Not specified

Primary Outcome Measures

Name	Time	Method
Ipsilateral breast local relapse rate 5 years from study registration is assessed through patient note review.

Secondary Outcome Measures

Name	Time	Method
<br> 1. Ipsilateral breast local relapse rate is measured by patient note review 10 years from study registration<br> 2. Regional relapse rate is measured by patient note reviewat 5 and 10 years<br> 3. Distant relapse rate is measured by patient note review at 5 and 10 years<br> 4. Overall survival is measured by patient note review at 5 and 10 years<br> 5. Breast cancer specific survival is measured by patient note review at 5 and 10 years<br>