Oncology is a branch of medicine that deals with cancer. A medical professional who practices oncology is an oncologist.

Oncology is concerned with:

• The diagnosis of any cancer in a person
• Therapy (e.g. surgery, chemotherapy, radiotherapy and other modalities)
• Follow-up of cancer patients after successful treatment
• Palliative care of patients with terminal malignancies
• Ethical questions surrounding cancer care
• Screening efforts:
  • of populations, or
  • of the relatives of patients (in types of cancer that are thought to have a hereditary basis, such as breast cancer