Epidemiology of Colorectal Cancer in England: is it changing? Somerset, Wiltshire, Avon and Gloucestershire SSG meeting Adam Chambers Colorectal Registrar Severn Deanery

Outline Worldwide trends in colorectal cancer epidemiology Changes in age-specific incidence in England South west data compared to English data Comparison with findings in other countries Future directions

Is (colo)rectal cancer increasing among young adults (<40years) in England?

Worldwide Incidence 2012 2030 1.4 million 2.2 million Ferlay et al., GLOBOCAN 2012, IARC

CRC incidence increases with HDI Low HDI Medium HDI High HDI/Very high HDI ↔ Incidence ↑ Mortality ↑ Incidence ↓ Mortality ↓ Incidence Gambia Mozambique Philippines Brazil UK Denmark US Austria Ferlay et al., GLOBOCAN 2012, IARC

Aims To determine whether the incidence of colorectal cancer is increasing among young adults (<40 years) To determine whether this differs according to site (colon vs. rectum) or gender

Methods Data collected by National Cancer Registration & Analysis Service (NCRAS) – 100% data completeness to 2010 and 98.4% to 2016 Operated by Public Health England (PHE) Adults aged ≥20 years from 1974 to 2015 Identification using ICD9 (153.0-153.9) & ICD10 (C18-C20) Grouped into 10 age bands Office for National Statistics (ONS) for mid-year populations estimates

Statistical Analysis Modelling Age-specific rate = Number of new cases in age group Mid-year population estimate of age group Age-standardised rate = ∑ (European standard population in age group X age-specific rate) ∑ European standard population in age group Modelling Joinpoint Regression to estimate annual percentage change/changes in incidence Age-period-cohort modelling

Largest study of CRC incidence worldwide Total CRC cases 1974-2015: 1,145,639 Colon: 726,887 Rectum: 418,752

The Elderly (>90 years) -2.1% +3.0% Incidence CRC (per 100,000) +1.3% Annual Percentage Change (%) in Colorectal Cancer Incidence

Screening Age (60-74 years) +1.0% -0.8% +4.5% -1.0% 60-69 years +1.3% -0.8% +1.4% -4.6% 70-74 years Incidence CRC (per 100,000) Incidence CRC (per 100,000) Annual Percentage Change (%) in Colorectal Cancer Incidence

Pre-screening middle age (40-59 years) +1.6% -0.7% Incidence CRC (per 100,000) +1.8 +1.2% Incidence CRC (per 100,000) -1.0% Annual Percentage Change (%) in Colorectal Cancer Incidence

The Young (<40 years) 20-29 years 30-39 years -4.8% +20.7% +12.7% -26.1% -2.9% Incidence CRC (per 100,000) Incidence CRC (per 100,000) +0.8% +1.4% Annual Percentage Change (%) in Colorectal Cancer Incidence

South West vs English CRC incidence rates

CRC incidence by anatomical site and gender (20-40years)

Age-period-cohort: Colon vs. Rectum

Is this an isolated phenomenon? USA Canada Brenner et al., Prev Med 2017 Siegel et al., JNCI 2017

Conclusions Increased incidence in young adults over last 20 years Birth-cohort effect observed after 1965 Similar trend in both colonic (IRR=2) and rectal cancer (IRR=3) Comparable trends seen in North America South West data mirrors English data Ecological data – no risk factor data

Future Directions Implications for screening and diagnosis - (qFIT) Identification of differences in phenotype/biology in this age group Understand the issues of living with CRC and its management for younger people Promote awareness in at risk groups

Acknowledgments Mr David Messenger Dr Steve Dixon Dr Paul White Consultant Colorectal Surgeon, University Hospitals Bristol Dr Steve Dixon Post-CCT Senior Clinical Fellow in Gastroenterology & MD candidate, University of Bristol Dr Paul White Associate Professor in Applied Statistics, University of West of England Mr Mike Thomas

Sources of Funding Elizabeth Blackwell Institute for Health Research Clinical Primer Fellowship Medical Research Council Clinical Research Training Fellowship David Telling Charitable Trust (Mr Adam Chambers)

Earlier diagnosis is critical in the younger patient <40 years ≥40 years P-value At presentation Poorly differentiated 27% 14% 0.014 N2 disease at presentation 37% 16% 0.001 Metastatic disease at presentation 38% 22% 0.019 Treated with curative intent Develop metastatic disease 56% 23% 0.003 5-year Overall Survival 54% 80% 0.029 Endreseth et al. (Norwegian Rectal Cancer Group), Dis Col Rectum 2006