- Patients with cancers deemed to have surgically non−resectable disease, patients refusing chemotherapy, patients unable to perform cardiopulmonary exercise testing (CPET) due to other coincident illness or conditions (e.g. arthritis), patients refusing surgery, patients withholding consent. Patients unable to give informed consent due to mental incapacity. Prisoners will be excluded. Patients in whom haemoglobin drops by >2g/dl between Visit 1 and visit 2.