Cancer diagnosis usually involves a combination of medical history, physical examination, laboratory tests and imaging such as CT, MRI, PET, ultrasound or X-rays. A biopsy is often needed to confirm whether abnormal cells are cancerous and can also provide information about the cancer type and grade. Once cancer is diagnosed, staging determines how extensive it is and whether it has spread to other parts of the body. The stage helps the cancer team understand the disease and plan appropriate treatment.

Cancer treatment depends on the type and stage of cancer, overall health and individual preferences. Options may include surgery, chemotherapy, radiation therapy, immunotherapy, targeted therapy and hormone therapy. Some cancers are treated with a single approach, while others require a combination of treatments. Treatment may aim to cure the cancer, remove or control it, reduce the risk of recurrence, slow its progression or relieve symptoms. Clinical trials may also provide access to newer treatment approaches for eligible patients.

Treatment decisions are based on more than the cancer's location. Specialists consider the type and stage of cancer, characteristics of the tumour, whether it has spread, the patient's overall health and other medical conditions, and the potential benefits and risks of available treatments. In some cancers, testing the tumour for specific molecular or genetic characteristics can help identify treatments that are more likely to work. The patient's preferences and goals are also important when developing an individualized treatment plan.

The role of each treatment varies according to the cancer. Surgery may be used to remove a tumour when it can be safely removed. Chemotherapy may be used to destroy cancer cells, sometimes before or after surgery or with other treatments. Radiation therapy uses high-energy radiation to target cancer cells and may be used alone or alongside other treatments. Immunotherapy helps the immune system recognize and attack cancer, while targeted therapy acts on specific abnormalities that help cancer cells grow.

Side effects vary considerably depending on the cancer and treatment, and many can be prevented, reduced or treated. Patients should tell their cancer care team about new or worsening symptoms rather than trying to manage significant side effects alone. Treatment may include medicines for nausea or pain, nutritional support, strategies for managing fatigue or other supportive care. Depending on the treatment, monitoring blood counts and organ function may also be important. Patients should ask which symptoms require urgent medical attention and whom to contact if they occur.

Useful questions include: What type and stage of cancer do I have? Will I need additional tests? What are my treatment options, and which do you recommend? What is the goal of treatment? What benefits and side effects should I expect? How soon should treatment begin, and how might it affect my daily life? Are there clinical trials or other treatment options I should consider? You can also ask whether a second opinion would be useful and how other health conditions may affect your treatment.