Professor Timothy Perren is a Consultant Medical Oncologist based at St James's University Hospital, part of The Leeds Teaching Hospitals NHS Trust.

Prof Perren trained in general medicine in London and Stoke on Trent. His oncology training was in Birmingham and at the Royal Marsden Hospital, London. He was appointed consultant medical oncologist at St James's Hospital in Leeds in January 1990. He specialises in the non-surgical treatment of cancers using chemotherapy, hormonal therapy and the new targeted molecular therapies. Prof Perren believes that it is important to take into account the individual needs and situation of each patient and to involve the patient and their family closely in the development of a treatment plan.

Professor Perren specialises in the treatment of breast cancer and gynaecological cancers, including ovarian cancer, cervical cancer and endometrial cancer. He provides treatment for newly diagnosed patients, as well as for those with recurrent or metastatic disease and has gained a high degree of knowledge and understanding of difficult constellation of symptoms that can often accompany cancer and its treatment. Professor Perren’s philosophy of patient care puts the patient at the centre of treatment planning. He believes in discussing all options of treatment before finally coming up with a solution that is best for the individual concerned. 

Professor Perren is a member of various organisations and groups including: fellow of the Royal College of Physicians; He is former Chair of the Joint Colleigate Council for Oncology and Joint Specialty Committee for Medical Oncology at the Royal College of Physicians; He is a member of the   American Society of Clinical Oncology; European Society of Medical Oncology; Association of Cancer Physicians; Yorkshire Cancer Network Breast Group; Yorkshire Cancer Network Gynaecology Group;National Cancer Research Institute Gynaecological Cancer Clinical Studies Group, and the UK Breast Cancer Intergroup.