• Tumour size on a breast report, and why it differs from the scan: The size on the pathology report is the largest continuous lump of invasive cancer measured under the microscope, which is not the same as the size on the mammogram or the MRI.
• Nottingham Prognostic Index (NPI), and PREDICT: One number that puts a breast cancer's size, its node status and its grade together, because the stage on its own leaves grade out.
• Ducts, lobules and the terminal duct lobular unit: The breast is a tree: fifteen to twenty branching duct systems, each ending in a cluster of milk-making sacs called a lobule.
• Nottingham grade (breast cancer grade 1, 2 and 3): The grade on a breast report is a sum of three scores: how much of the tumour still forms tubes, how ugly its nuclei are, and how many cells are caught dividing.
• The WHO classification of breast tumours, and what the 6th edition changed: The book that decides what a breast tumour is called.
• Mastectomy: Removing the whole breast, either for cancer or preventively in BRCA1/2 carriers, where bilateral risk-reducing mastectomy cuts breast cancer risk by 90% or more.

Biomarker results to ask for: E-cadherin loss on immunohistochemistry and CDH1 inactivation, Oestrogen and progesterone receptor (almost always positive), HER2 (usually negative), PTEN, TBX3 and FOXA1 mutations (enriched), Extent on MRI or contrast-enhanced mammography before surgery.

Bring copies of scan reports, pathology and blood results, and a list of every medicine and supplement.

• All stages: Treated as HR-positive breast cancer: surgery planned with MRI, endocrine therapy, CDK4/6 inhibitors in advanced disease; sentinel node biopsy as in ductal disease. (HR-positive / HER2-negative breast cancer, Endocrine therapy (SERMs, AIs, SERDs), CDK4/6 inhibitors, Tamoxifen, Letrozole (and other aromatase inhibitors), Mastectomy)

From the standard of care recorded for this cancer; which apply depends on your stage and biomarkers. Ask which the team recommends and why.