Oncology is a branch of medicine that deals with treatment of tumours. A medical professional who practices oncology is an oncologist. Clinical oncology enfolds the non-surgical aspect of oncology. 85% of all clinical oncologists treat patients with a balance of chemotherapy and radiotherapy. Clinical oncologists are involved in the treatment of all types of cancer. They work intently in large multidisciplinary teams that focus on the treatment of cancer affecting parts of the body or systems. They treat patients and manage their cancer throughout the disease. This specialty gives the opportunity of developing clinical and scientific skills with great potential for academic and clinical research. Technologies in the field of clinical oncology are improving promptly. For example, some tumours can be treated with highly sophisticated precision external beam radiation therapy such as proton beam therapy. Some patients can be cured, but for others the emphasis is on effective palliative care and improving quality of life.