Interval colorectal cancers after negative faecal immunochemical test in the New Zealand Bowel Screening Pilot.

OBJECTIVE: Evaluate the diagnostic performance of faecal immunochemical test (FIT), identify risk factors for FIT-interval colorectal cancers (FIT-IC) and describe long-term outcomes of participants with colorectal cancers (CRC) in the New Zealand Bowel Screening Pilot (BSP). DESIGN: From 2012 to 2017, the BSP offered eligible individuals, aged 50-74 years, biennial screening using a quantitative FIT with positivity threshold of 15 µg haemoglobin (Hb)/g faeces. Retrospective review of prospectively maintained data extracted from the BSP Register and New Zealand Cancer Registry identified any CRC reported in participants who returned a definitive FIT result. Further details were obtained from hospital records. FIT-ICs were primary CRC diagnosed within 24 months of a negative FIT. Factors associated with FIT-ICs were identified using logistic regression. RESULTS: Of 387 215 individuals invited, 57.4% participated with 6.1% returning positive FIT results. Final analysis included 520 CRC, of which 111 (21.3%) met FIT-IC definition. Overall FIT sensitivity for CRC was 78.7% (95% CI=74.9% to 82.1%), specificity was 94.1% (95% CI=94.0% to 94.2%). In 78 (70.3%) participants with FIT-IC, faecal Hb was reported as undetectable. There were no significant associations between FIT-IC and age, sex, ethnicity and deprivation. FIT-ICs were significantly associated with proximal tumour location, late stage at diagnosis, high-grade tumour differentiation and subsequent round screens. Median follow-up time was 74 (2-124) months. FIT-IC had significantly poorer overall survival. CONCLUSION: FIT sensitivity in BSP compared favourably to published data. FIT-ICs were more likely to be proximal tumours with poor long-term outcomes. Further lowering of FIT threshold would have minimal impact on FIT-IC.

Faecal immunochemical test to triage patients with possible colorectal cancer symptoms: meta-analysis.

BACKGROUND: This review evaluated the utility of single quantitative faecal immunochemical test (FIT) as a triaging tool for patients with symptoms of possible colorectal cancer, the effect of symptoms on FIT accuracy, and the impact of triaging incorporating FIT on service provision. METHODS: Five databases were searched. Meta-analyses of the extracted FIT sensitivities and specificities for detection of colorectal cancer at reported f-Hb thresholds were performed. Secondary outcomes included sensitivity and specificity of FIT for advanced colorectal neoplasia and serious bowel disease. Subgroup analysis by FIT brand and symptoms was undertaken. RESULTS: Fifteen prospective cohort studies, including 28 832 symptomatic patients were included. At the most commonly reported f-Hb positivity threshold of ≥ 10 µg Hb/g faeces (n=13), the summary sensitivity was 88.7% (95% c.i. 85.2 to 91.4) and the specificity was 80.5% (95% c.i. 75.3 to 84.8) for colorectal cancer. At lower limits of detection of ≥ 2 µg Hb/g faeces, the summary sensitivity was 96.8% (95% c.i. 91.0 to 98.9) and the specificity was 65.6% (95% c.i. 59.0 to 71.6). At the upper f-Hb positivity thresholds of ≥ 100 µg Hb/g faeces and ≥ 150 µg Hb/g faeces, summary sensitivities were 68.1% (95% c.i. 59.2 to 75.9) and 66.3% (95% c.i. 52.2 to 78.0), with specificities of 93.4% (95% c.i. 91.3 to 95.1) and 95.1% (95% c.i. 93.6 to 96.3) respectively. FIT sensitivity was comparable between different assay brands. FIT sensitivity may be higher in patients reporting rectal bleeding. CONCLUSION: Single quantitative FIT at lower f-Hb positivity thresholds can adequately exclude colorectal cancer in symptomatic patients and provides a data-based approach to prioritization of colonoscopy resources.

Manometry of the Human Ileum and Ileocaecal Junction in Health, Disease and Surgery: A Systematic Review.

Background: The terminal ileum and ileocaecal junction form a transition zone in a relatively inaccessible portion of the gastrointestinal tract. Little is known about the motility of this region with few detailed studies, indicating the need for a robust synthesis of current knowledge. This review aimed to evaluate the quantitative and qualitative data on the manometry findings of the terminal ileum and ileocaecal junction during the fasting and post-prandial periods in healthy individuals and patients with motility disorders or patients after bowel surgery. Methods: A systematic search of five databases (Medline, Pubmed, Embase, Scopus, and Cochrane Library) was performed. Studies that presented manometry data from the human ileum or ileocaecal junction were included. Results: Forty-two studies met the inclusion criteria. The main motility patterns reported in the terminal ileum during fasting were the migrating motor complex, discrete clustered contractions, prolonged propagated contractions and phasic contractions. Post-prandial motility featured irregular, intense contractions. Some studies found a region of sustained increased pressure at the ileocaecal junction while others did not. Patients with motility disorders showed differences in manometry including retrograde propagation of phase III. Patients post-bowel surgery showed differences including higher incidence of phase III. Conclusion: Motility patterns of the terminal ileum differ between fasting and fed states. Large variability existed in manometry recordings of the terminal ileum. Technical challenges and lack of standardized definitions may reduce accuracy of manometry assessment. Further research is needed to understand how this key portion of the gut physiologically functions.

Treatment of gastric adenocarcinoma at a New Zealand centre: meeting the challenges of a low volume country.

BACKGROUND: Surgical treatment of gastric cancer in New Zealand is challenging because of a low annual incidence of 400 patients and population dispersal over a wide area with little data on regional treatment trends and outcomes. This investigation was undertaken to evaluate the surgical outcomes of gastric cancer patients presenting to a single upper gastrointestinal centre (WDHB, Waitemata District Health Board) and to compare these to national and international standards. METHODS: Data on 135 patients with histologically proven gastric adenocarcinoma presenting between January 2010 and December 2014 were reviewed and compared with nationally available procedural volume data. RESULTS: Sixty of 135 patients were resected (resection rate 44%) and 75 patients were managed with palliative chemotherapy/symptomatic care alone. Twenty-six patients (43%) received adjuvant or neoadjuvant chemotherapy and only two patients (3%) underwent laparoscopic resection. In resected patients, 90-day mortality was 1.6%, and 11 patients (18%) developed complications ≥ Clavien-Dindo grade 3. Fifty-two patients (87%) had ≥15 lymph nodes resected and 54 patients (90%) had a histological R0 resection. At median follow-up of 49 months, 30 patients remain alive and disease-free with 20 true 5-year disease-free survivors. National data between 2010 and 2014 showed WDHB performed 20% (338/1710) of gastric resections for all indications in New Zealand. CONCLUSION: While WDHB is an internationally low volume centre for gastric cancer, surgical outcomes benchmark satisfactorily to international standards. New Zealand's national treatment standards should set aspirational goals for gastric cancer treatment and have a clear strategy to address issues of surgical volume and national service provision.