Oncology is a branch of medicine that deals with the study, treatment,

diagnosis and prevention of cancer

A medical professional who practices oncology is an oncologist

The name's etymological origin is the Greek word ὄγκος (ónkos), meaning "tumor", "volume" or "mass"

The diagnosis of any cancer in a person (pathology)

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