Endocrine Abstracts

Background: Colorectal cancer is the third most common cancer in the UK this had led to development of the bowel cancer screening programmes (BCSPs). It is known that ileo-colonic NETs are increasing in incidence in part thought to be related to increased endoscopy. There are few epidemiological data on rectal or ileal NETs diagnosed in BCSPs. This study aims to identify the number of NETs diagnosed through the UK BCSP.

Methods: UK bowel cancer colonoscopy data is stored on the Exeter database managed by Public Health England (PHE). Queries were developed by PHE to capture potential NET related search terms across relevant data tables in the Exeter database. Queries were run to identify BCSP participants attending for colonoscopy with NET-related coding from 2006 to December 2014. A written proforma was sent to the responsible BCSP clinician for all participants identified with NET related search terms. The proforma contained questions on tumour characteristics and further patient management.

Results: 216707 participants had colonoscopies. There were 146 unique BCSP participants with NET related codes across the 3 database tables in this time period. 60% of the 146 participants were male (n=87). Primary sites: colorectal region (n=102, 70%), ileum (n=24, 16%), unknown (n=18, 12%) and appendix (n=2, 1%).

The incidence of ileo-colonic NETs was 67 per 100,000 colonoscopies per year. 85% of participants with this data available were reported as grade 1 (83/98) with 8% as grade 2 (8/98) and 7% as grade 3 (7/98). Data on the presence of metastatic disease was available in 95/110 (86%). Metastases were present in 24% of cases (23/95); colonic (10/ 17) or ileal NETs (9/27). 94% (102/108) with a validated NET were discussed in a multidisciplinary meeting (MDM), mostly in colorectal MDMs (82%, 89/108) rather than a specific NET MDM (12%, 13/108). Additional recommendations were made in 82% of instances (63/77).

Discussion: This is the first data reporting on incidence of ileo-colonic NETs within a national bowel cancer screening programme. It provides evidence of early stage of disease at presentation of ileo-colonic NETs.