Is it possible to be officially diagnosed with cancer when blood results are clear and they haven't done a biopsy? my mother in law is currently in hospital, shes been in pain for 2 years with a lump on her back and they have kept sending her away saying its artheritis. This past week she has been so bad with it she pushed the hospital to do further tests which consisted of blood tests, MRI & CT scans. Blood tests were clear but MRI & CT showed tumours, my question is how do they know these tumour are cancerous without a biopsy? I understand they see it every day and I am aware that it most likely is cancer but are they allowed to fully diagnose you without a blood test or a biopsy confirming it? The hospital she is under have severely mistreated and neglected her, they are also unable to tell us what form of cancer it is and what stage she is in but that she definetley has it so i just wanted to make sure that what they are saying is corect. Thanks x