Table 1 Overview of the inclusion and exclusion criteria for the RICE trial

Age ≥ 60 years

Previous radiotherapy to the same breast

Unifocal

Suspicious diffuse microcalcifications

Tumor visible on pre-treatment imaging

Invasive lobular carcinoma on core biopsy

Tumor size on pre-treatment imaging ≤ 2 cm

Lymphovascular invasion on core biopsy

Grade 1–2 on pre-treatment core biopsy

Any clinical nodal or metastatic disease

Estrogen receptor (ER) and progesterone (PR) positive (> 10%)

Human epidermal growth factor receptor 2 (HER2) positive

Clinically node-negative

Prior non-hormonal therapy

Breast primary tumor visible on MR radiation oncology imaging (with or without IV contrast) for treatment localization

Skin or chest wall involvement

Collagen vascular disease (e.g., lupus, scleroderma)

Pregnant or lactating

Absolute contraindications to MRI (e.g., incompatible implants, unable to tolerate duration)