Abstract
Small intestine neuroendocrine tumours (SI-NETs) are often diagnosed late with a UK median of 3 years and high misdiagnosis rates. Previous studies, largely based on patient surveys, offer little data on improving diagnosis. In 2017, the South Wales NET service underwent a nationally commissioned, systematic transformation, aiming to improve diagnosis through the development of a gastroenterology and surgical referral network, and education of these specialities. This study aims to assess the impact of the transformation on SI-NET diagnosis times and misdiagnosis rates using accurate hospital data, along with the diagnostic routes and investigations used for SI-NETs. We retrospectively analysed the hospital records of 224 patients diagnosed with SI-NETs referred to the South Wales NET service (110 pre-transformation and 114 post-transformation). Following the service transformation, there was a significant reduction in diagnosis times from a median of 12.5-5.2 months (p < .05), at an earlier stage (cases with metastases reduced from 77% to 62%), and reduced misdiagnosis rates from 40% to 25%. Colonoscopy, used to investigate the presenting gastrointestinal symptoms in 42% of patients prior to diagnosis, identified an abnormality in only 28%, compared with 97% with computed tomography (CT) scans. A gastroenterology and surgical referral network across hospitals may improve diagnosis in SI-NETs, leading to earlier detection and reducing misdiagnosis rates. Further exploration of GP interactions is needed. Caution is needed following negative colonoscopy in patients with persistent lower gastrointestinal symptoms as this could lead to missed SI-NET diagnosis if further abdominal imaging is not undertaken.