When is chemotherapy after surgery recommended for breast cancer?

Surgery removes the visible breast tumour, but very small cancer cells can remain elsewhere in the body. Adjuvant chemotherapy is a whole-body treatment intended to destroy or control these cells before they form a new tumour. The decision considers tumour size, grade, hormone-receptor and HER2 results, lymph-node findings, surgical margins, overall health, and sometimes a genomic test. Chemotherapy is not needed for every person with breast cancer; hormone therapy, HER2-targeted treatment, radiotherapy, or observation may be more suitable depending on the cancer profile.

Review the pathology report with your breast cancer team and ask which findings influence the recommendation. Discuss the expected benefit alongside possible effects such as tiredness, nausea, hair loss, infection risk, fertility concerns, or nerve symptoms. If chemotherapy is chosen, treatment is usually given in cycles with checks of blood counts and organ function between cycles. Tell the team about medicines, pregnancy plans, other illnesses, and any fever or infection before treatment begins.

Contact the oncology team promptly for a fever, chills, new shortness of breath, uncontrolled vomiting, severe diarrhoea, unusual bleeding, or a sudden allergic-type reaction during or after treatment. After surgery, urgent assessment is also needed for rapidly worsening redness, swelling, wound discharge, or severe pain. These symptoms need attention because chemotherapy can affect infection-fighting blood cells and healing.

Ask: What features of my pathology report support chemotherapy? Would a genomic test change the recommendation? What other treatments are planned, and how will their order be decided? Which side effects should be reported the same day?