Chemotherapy

Chemotherapy is a cancer treatment that uses powerful medicines to kill cancer cells or stop them from growing and dividing.

Cancer cells grow and divide much faster than most normal cells. Chemotherapy medicines travel through the bloodstream and target cells that are dividing rapidly. Because of this, they can reach cancer cells almost anywhere in the body. The medicines damage the cancer cell's ability to copy itself, so the tumour shrinks or stops growing. Some normal cells that also divide quickly — such as those lining the mouth and gut, or cells in hair follicles (the tiny pockets in the skin that hold each hair) — can also be affected, which is why side effects occur.

Chemotherapy is used across a wide range of cancers and can be given with different goals depending on the situation — to cure the cancer, to shrink it before another treatment, to destroy any remaining cells after surgery, or to control symptoms when a cure is not the aim.

• Breast cancer — often given before surgery to shrink the tumour, or after surgery to reduce the chance of return.
• Lung cancer — including both non-small-cell and small-cell types.
• Colorectal cancer (cancer of the large intestine or rectum).
• Lymphoma (cancer of the lymphatic system, the network of vessels that carries immune cells).
• Leukaemia (cancer of the blood or bone marrow).
• Ovarian cancer and other gynaecological (relating to the female reproductive system) cancers.
• Head and neck cancers.
• Stomach and oesophageal (relating to the food pipe) cancers.
• Bladder cancer.
• Bone and soft-tissue sarcomas (cancers that start in connective tissues such as muscle or fat).
• Preparation for a stem-cell transplant, to clear existing bone marrow.

Chemotherapy is not suitable for everyone. Your oncologist (cancer specialist) will review your overall health before recommending it. It is usually avoided or used with extra caution in situations such as:

• Severely reduced kidney or liver function, because these organs clear the medicines from the body.
• Very low blood cell counts before treatment begins.
• Active serious infection that has not yet been treated.
• Pregnancy — certain regimens (treatment plans) carry risk to the developing baby, so timing and medicine choice require very careful consideration.
• Extremely poor general health where the body may not tolerate the treatment.

Chemotherapy affects rapidly dividing cells throughout the body, not only cancer cells, so side effects are common — though their severity varies greatly from person to person and depends on which medicines are used.

• Fatigue (extreme tiredness) — one of the most frequently reported effects, and it can persist throughout treatment.
• Nausea and vomiting — very common; medicines to control nausea are usually given alongside chemotherapy.
• Hair loss — because hair follicle cells divide quickly; hair typically regrows after treatment ends.
• Increased risk of infection — chemotherapy can lower white blood cell counts, reducing the body's ability to fight infections (this state is called neutropenia).
• Anaemia (low red blood cell count) — causing tiredness, breathlessness, and pale skin.
• Bleeding or bruising easily — due to lower platelet (the tiny blood cells that help clotting) counts.
• Mouth sores and difficulty swallowing — caused by damage to the lining of the mouth and throat.
• Loss of appetite and weight loss.
• Diarrhoea or constipation.
• Peripheral neuropathy (nerve damage in the hands and feet) — tingling, numbness, or pain, which may last after treatment ends.
• Kidney or liver stress — some medicines can strain these organs; blood tests are done regularly to monitor them.
• Heart effects — certain chemotherapy medicines can affect heart muscle over time; your doctor will monitor this.
• Fertility effects — chemotherapy can affect the ability to have children; this should be discussed before treatment starts.
• Secondary cancers — a rare long-term risk; some chemotherapy medicines slightly increase the chance of a different cancer appearing years later.

Preparation for chemotherapy is thorough because the treatment needs to be tailored carefully to your body and your cancer. The steps below are typical, but your care team may adjust them.

Before treatment begins, your doctor will usually ask you to: stop or adjust blood thinners or other medicines that could interact with the chemotherapy; avoid alcohol in the days leading up to each cycle (a cycle is one round of treatment followed by a rest period); tell the team about all supplements and herbal remedies you take, as some can interfere with chemotherapy medicines; and not smoke if possible, since smoking can reduce how well treatment works and slow recovery.

Fasting is not always required for chemotherapy itself, but if a port (a small device placed under the skin to give medicine easily) is being inserted beforehand, fasting instructions will be given for that minor procedure. Always follow the specific guidance your team provides.

Tests that are commonly done before and during a course of chemotherapy include:

• Blood tests to check blood cell counts, kidney function, and liver function — these are usually repeated before every cycle.
• Heart tests such as an echocardiogram (an ultrasound scan of the heart) or EKG (electrocardiogram, a recording of the heart's electrical activity) if the planned medicines are known to affect the heart.
• Imaging scans such as CT or MRI to measure the tumour before treatment starts, so progress can be compared later.
• A dental check — mouth infections can become serious during chemotherapy, so dentists may treat problems in advance.
• Fertility counselling and sperm or egg banking, if the patient wishes to have children in the future.

What happens during a chemotherapy session, step by step (the exact number and order of steps will vary by hospital and medicine type):

• You arrive at the chemotherapy day unit or ward and your identity and treatment plan are confirmed.
• A nurse checks your blood pressure, temperature, weight, and recent blood test results to make sure you are safe to proceed.
• A cannula (a thin, flexible tube) is placed into a vein in your arm, or an existing port is accessed, to deliver the medicines into the bloodstream. Some chemotherapy medicines are given as tablets.
• Pre-medications — such as anti-nausea medicines and fluids — are given first through the drip to prepare your body.
• The chemotherapy medicine or medicines are then administered slowly through the drip. The infusion can take anywhere from under an hour to many hours depending on the regimen.
• Nursing staff monitor you throughout for any immediate reactions such as flushing, breathing changes, or pain at the infusion site.
• Once the infusion is complete, the drip is removed or capped, and you are observed for a short period before going home or to your room.

Most chemotherapy is given on an outpatient basis, meaning you go home the same day, though some regimens or complications require a hospital stay. Recovery between cycles is just as important as the treatment itself, because the body needs time to rebuild healthy cells before the next round.

• Monitoring: Blood tests are done regularly — usually before each new cycle — to check that blood cell counts and organ function are recovering well enough to continue safely.
• Infection precautions: During the days when white blood cell counts are at their lowest (often around one to two weeks after each dose), it is important to avoid crowded places, practice careful hand hygiene, and report any fever promptly to the care team, as fever during chemotherapy can be a medical emergency.
• Wound or port care: If a central line or port has been inserted under the skin to deliver medicines, the site needs to be kept clean and dry according to the nurse's instructions. Signs of redness, swelling, or discharge should be reported immediately.
• Eating and drinking: Small, frequent meals are often easier to tolerate. Staying well hydrated helps the kidneys clear medicines from the body. The dietitian (a specialist in nutrition) attached to the oncology team can give personalised advice.
• Mouth care: Rinsing with a gentle, non-alcohol mouthwash several times a day can help reduce mouth sores. Any new sores, bleeding gums, or difficulty swallowing should be reported to the team.
• Activity: Rest is important, but gentle movement such as short walks is usually encouraged when energy allows, as it can help manage fatigue.
• Medicines at home: Anti-nausea medicines and other supportive medicines are usually prescribed to take between sessions. These should be used as directed by the care team.
• Avoiding infections: Live vaccines (such as some flu vaccines) are generally avoided during chemotherapy. The oncology team will advise on which vaccines are safe.
• Fertility and contraception: Even if fertility is reduced, pregnancy during chemotherapy carries serious risks. The care team will discuss appropriate contraception.
• Follow-up scans and appointments: Imaging scans are repeated at intervals set by the oncologist to assess whether the cancer is responding to treatment. Attendance at these appointments is essential.
• Emotional support: Mood changes, anxiety, and low mood are common. Oncology social workers, counsellors, and support groups are usually available and can make a real difference.