Breast Cancer

Breast cancer is biologically diverse, and the subtype determines everything about treatment and prognosis. Hormone receptor positive disease responds to endocrine therapy over five to ten years; HER2-positive disease is transformed by targeted antibodies; triple-negative disease relies on chemotherapy and, increasingly, immunotherapy. Modifiable risk is real but modest at the individual level: alcohol shows a dose-dependent relationship with incidence, post-menopausal obesity raises risk through peripheral oestrogen production, and regular physical activity lowers both incidence and recurrence. On supplements, two issues matter most. Soy isoflavones, long feared for oestrogenic activity, are associated with lower recurrence in cohort studies of survivors rather than higher. Conversely, high-dose antioxidants during chemotherapy have been associated with worse disease-free survival in observational data, and St John's wort reduces tamoxifen efficacy through CYP induction.

• •A new lump in the breast or armpit
• •Skin dimpling or puckering
• •Nipple inversion or discharge
• •Change in breast size or shape
• •Persistent breast or armpit pain
• •Skin redness or thickening resembling orange peel

• •Increasing age
• •BRCA1, BRCA2 and other inherited mutations
• •Early menarche and late menopause
• •Nulliparity or late first pregnancy
• •Post-menopausal obesity
• •Alcohol intake
• •Combined hormone replacement therapy
• •Prior chest radiotherapy

Hormonal exposure over a lifetime, inherited mutations including BRCA1 and BRCA2, dense breast tissue, post-menopausal adiposity driving aromatase activity, alcohol, and age.