the uk national bowel cancer screening program invites men and women aged between 60  74 years old to be routinely screened every 2 years ( 1 ) . this is based on the finding that population screening using biennial faecal occult blood testing has demonstrated a 16% reduction in mortality from colorectal cancer ( 2 ) . a uk pilot study has successfully demonstrated this as a feasible and reliable method of screening ( 3 ) . screening endoscopists are required to pass an endoscopy  driving test before being allowed to screen and have their screening data rigorously evaluated . a 90% caecal intubation rate , verified by visualisation of the ileocaecal valve and appendix orifice , or intubation of the terminal ileum of these , terminal ileal intubation with ileoscopy has the additional benefit of determining whether the source of bleeding is the distal ileum . we present a case where terminal ileal intubation carried out during a screening colonoscopy led to the identification and treatment of a pathology that if missed , could have a significantly worsened prognosis . a 74 year old man was referred to our endoscopy unit after a positive faecal occult blood test . he had no preceeding symptoms or history that would place him at increased risk of colorectal cancer . at colonoscopy , excellent views were obtained to the ileocaecal valve ( icv ) and appendix orifice , confirming identification of the caecum . with no colonic pathology seen , the endoscopist proceeded to intubate the icv , as part of his routine practice . a 3 cm ileal polyp was identified 5 cm proximal to the valve ( figure 1 ) and biopsies were taken . endoscopic view of the carcinoid tumour in the distal ileum histology demonstrated features of a classical neuroendocrine carcinoid tumour infiltrating the muscularis mucosa . abdominal ct scan , black arrow highlighting the carcinoid tumour in the distal ileum ct scanning demonstrated the lesion intususscepting into the terminal ileum . ( figure 2 ) resected specimen , black arrow demonstrating the carcinoid tumour in the opened distal ileum the patient underwent a laparoscopic right hemicolectomy one month after diagnosis . twelve out of fifteen lymph nodes resected were involved with further evidence of extranodal spread . carcinoids are neuroendocrine tumours derived from enterochromaffin cells most commonly found in the gastrointestinal tract ( 65% of cases ) with an annual incidence of approximately two per 100,000 cases . around 22% of cases present with distant metastases and in half these cases no primary tumour can be found ( 4 ) . despite evidence for improving colonic diagnoses , completion of colonoscopy by passing through the icv this is due to the perceived difficulty of intubating the valve as well as the anticipated increase in procedure time . with practice , ileoscopy has been shown to be achievable in at least 85% of routine colonoscopies . in skilled hands , it adds on average just additional 3 minutes to the procedure and contributes significantly to quality assurance and diagnostic yield ( 5 ) .
the uk national bowel cancer screening programme invites men and women aged between 60  74 years old to be routinely screened every 2 years . a 90% caecal intubation rate or intubation of the terminal ileum 
 is considered to be the best practice means of identifying completeness . 
 this case report describes how terminal ileal intubation carried out during a routine screening colonoscopy led to the identification and treatment of a carcinoid tumour . despite evidence for improving colonic diagnoses , completion of colonoscopy by passing through the ileocaecal valve 
 is not performed routinely due to the perceived difficulty of the manoeuvre . with practice 
 , ileoscopy has been shown to be achievable in at least 85% of routine colonoscopies and contributes significantly to quality assurance and to the diagnostic yield .