Professor Aziz is a Manchester Academic Health Science Centre Honorary Clinical Chair at the University of Manchester and a Consultant Colorectal Surgeon at The Christie, one of Europe's largest comprehensive cancer hospitals. As the clinical lead for the peritoneal tumour service at The Colorectal & Peritoneal Oncology Centre (CPOC), he specialises in  complex minimally invasive (keyhole) and open surgical techniques to treat early, advanced, and recurrent tumours of the appendix, colon, and rectum, including those that have spread to the lining of the abdomen (peritoneum), for which he performs cytoreductive surgery (CRS) with hyperthermic intra-peritoneal chemotherapy (HIPEC). Approximately 200 CRS/HIPEC procedures are carried out at The Christie CPOC each year. He is also a specialist in retroperitoneal sarcomas, has been the endoscopy lead for the trust, the clinical lead for colorectal surgery, and is a national laparoscopic colorectal surgery trainer. 

Professor Aziz has developed evidence synthesis techniques to better guide healthcare decision-making and published over 100 peer-reviewed research papers, some of which have been used to guide institutions such as the UK National Institute of Clinical Excellence (NICE). He was a member of the 2007 ‘Healthcare for London-A Framework for Action’ team reviewing the capital’s healthcare needs and have an interest in translating biomedical research into new technologies for patient benefit.

To date Professor Aziz has obtained grants from Innovate UK, Medical Research Council, Technology Strategy Board, and National Institute for Healthcare Research. He is a cofounder of Smart Surgical Appliances Ltd, a medical device company developing sensor-enabled technologies to increase the adoption of minimally invasive surgery. He is the UK primary investigator for a 5-year CRUK accelerator award to identify biomarkers and develop treatment options for patients with pseudomyxoma peritonei and a co-investigator on a 3-year NIHR HTA grant evaluating the cost-effectiveness of CRS/HIPEC in treatment of ovarian, colorectal, and gastric adenocarcinoma. Professor Aziz leads the CPOC lab at the Manchester Cancer Research Centre which is at the cutting edge of translational research in peritoneal tumours.