The purpose of the study is:

• to assess the potential benefits of 18F-[FDG] PET/CT and PET/MRI for operable breast cancer in order to define the size and location of the primary tumor, as well as axillary, supraclavicular and internal mammary lymph nodes.
• to apply the imaging results to the simulation and the radiation treatment planning and partial breast for 3-D radiation treatment and partial breast irradiation with intensity modulated radiation treatment (IMRT).

Pre-operative FDG PET/CT, and in option PET/IRM, are intended for women with histologically confirmed operable clinically node-negative breast cancer, in whom breast conserving and post-operative radiotherapy are planned.

Inclusion Criteria:

• Histologically confirmed breast carcinoma
• Clinical stage T1-2 N0 M0
• Age > 18 years
• Signed informed consent

Exclusion Criteria:

• WHO performance index 3
• Premenopausal women without contraception
• Gestation
• Lactating
• Prior surgery or radiotherapy on the same breast
• Unable to understand study participation
• Bilateral breast cancer
• Prior CT thorax-abdomen and breast MRI within 4 months of interview
• Presence of electromechanical implant and/or body ferromagnetic material
• Previous history of renal insufficiency requiring dialysis and/or hospitalisation
• Ureum and/or creatinine within 2 weeks of interview above lab's reference limits
• History of contrast allergy
• Hyperthyroidy
• Claustrophobia.

Women with operable clinically node-negative breast cancer