Imperial College London


Faculty of MedicineDepartment of Surgery & Cancer

Honorary Clinical Lecturer



+44 (0)20 3312 7657s.markar




Queen Elizabeth the Queen Mother Wing (QEQM)St Mary's Campus





From 2013 to 2016, I was awarded doctoral research fellowship by the National Institute for Health Research (NIHR) in the United Kingdom, through which I undertook my first PhD at Imperial College London. The subject was basic science focusing on non-invasive breath analysis of volatile organic compounds (breath test) for the diagnosis of gastro-intestinal cancer. From 2015 to 2018 I undertook my second PhD at Karolinska Institutet in Sweden, through which I developed further knowledge in clinical research in the surgical treatment of oesophageal cancer.

In 2016, I was awarded my first postdoctoral position with a NIHR Clinical Trials fellowship, to support my training in the design and conduct of randomised clinical trials /RCTs) at Imperial College London. Through this fellowship I was also able to work on an RCT comparing minimally invasive with open surgery for oesophageal cancer, which was published in New England Journal of Medicine. In 2017 I was appointed as NIHR Clinical Lecturer in Oesophago-Gastric Surgery at Imperial College London. The focus of my research became cancer survivorship, through which I coordinated three large multi-center European studies with recruitment of over 1000 oesophageal cancer survivors. I also continued my basic science research in breath test analysis as supervisor of PhD students, studying breath profiling of early oesophageal cancer and its premalignant lesion (Barrett’s oesophagus).  



Sounderajah V, Ashrafian H, Rose S, et al., 2021, A quality assessment tool for artificial intelligence-centered diagnostic test accuracy studies: QUADAS-AI, Nature Medicine, ISSN:1078-8956

Kamarajah SK, Sylla P, Markar SR, 2021, Racial disparity in curative treatment and survival from solid-organ cancers., Br J Surg, Vol:108, Pages:1017-1021

Markar SR, Sounderajah V, Johar A, et al., 2021, Patient-reported outcomes after oesophagectomy in the multicentre LASER study., Br J Surg, Vol:108, Pages:1090-1096

Liu Y, Pettersson E, Schandl A, et al., 2021, Psychological distress after esophageal cancer surgery and the predictive effect of dispositional optimism: a nationwide population-based longitudinal study, Supportive Care in Cancer, ISSN:0941-4355

Chidambaram S, Sounderajah V, Maynard N, et al., 2021, Evaluation of postoperative surveillance strategies for esophago-gastric cancers in the UK and Ireland., Dis Esophagus

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