Response assessment and follow-up by imaging in gastrointestinal tumours

Abstract

Response assessment with imaging in gastrointestinal tumours can serve different clinical goals. In tumour types that are primarily surgically treated, imaging can be used to assess response to neoadjuvant treatment, determine resectability and help decide on the best surgical approach. In patients who are primarily undergoing medical (systemic) treatment, imaging can be used to monitor tumour responsiveness in order to optimize or alter the treatment plan in any patient not achieving a satisfactory response, thereby avoiding prolonged ineffective treatment. In this chapter, the use of imaging in these respective settings will be illustrated using rectal cancer and gastro-enteropancreatic neuro-endocrine tumours (GEP-NET) as examples.