Individual Abstract within a Delegate Designed Symposium 2025 Joint Meeting of the COSA ASM and IPOS Congress

Time to diagnosis and treatment of younger vs older adults with colorectal cancer: insights from linked health data (126367)

Rebecca J Bergin 1 2 3 , Allison Drosdowsky 2 , Silja Schrader 2 , Victoria White 4 5 , Roger L Milne 3 6 7 , Robert J Thomas 3 8 , Dallas English 3 6 , Sophie Boffa 9 , Julie Marker 10 , Jody Horne 11 , Amanda Piper 12 , John Ding 13 14 , Finlay A Macrae 14 15 16 , Jon D Emery 2
  1. Centre for Quality and Patient Safety Research, Institute of Health Transformation, Deakin University, Geelong, Vic, Australia
  2. Department of General Practice and Primary Care, University of Melbourne, Melbourne, Vic, Australia
  3. Cancer Epidemiology Division, Cancer Council Victoria, Melbourne, VIC, Australia
  4. School of Psychology, Deakin University, Melbourne, VIC, Australia
  5. Behavioural Science Division, Cancer Council Victoria, Melbourne, VIC, Australia
  6. Melbourne School of Population and Global Health, The University of Melbourne, Melbourne, Vic, Australia
  7. Precision Medicine, School of Clinical Sciences at Monash Health, Monash University, Melbourne, VIC, Australia
  8. Faculty of Medicine, Dentistry and Health Sciences, The University of Melbourne, Melbourne, Vic, Australia
  9. National Consumer Committee, ECORRA program, Deakin University, Melbourne, VIC, Australia
  10. Consumer representative, Narooma
  11. Consumer representative, QLD
  12. Strategy and Support Division , Cancer Council Victoria, Melbourne, VIC, Australia
  13. Gastroenterology Department, St Vincent's Hospital, Melbourne, VIC, Australia
  14. Department of Medicine, University of Melbourne, Melbourne, VIC, Australia
  15. Colorectal Medicine and Genetics, Royal Melbourne Hospital, Melbourne, VIC, Australia
  16. Genomic Medicine and Family Cancer Clinic, Royal Melbourne Hospital, Melbourne, VIC, Australia

Objectives/purpose: More advanced stage in younger adults with colorectal cancer (aged under 50) negatively impacts survival and quality of life. Prolonged time to diagnosis may be important but is underexplored. This study examined time from presentation to diagnosis, colonoscopy and treatment of younger vs older adults with colorectal cancer.

Sample and setting: Primary care medical record data, hospital administrative data and Victorian Cancer Registry (VCR) data were linked for people diagnosed with colorectal cancer between 2008 and 2022 in Victoria, Australia. Three separate samples were created, maximising sample size, to calculate three intervals: 1) presentation in primary care with a colorectal cancer-related symptom to diagnosis (n=809, 11% under 50; all datasets); 2) referral to colonoscopy (n=5,101, 9% under 50, public patients only; Victorian Integrated Non-Admitted Health data, Victorian Admitted Episodes Dataset (VAED) and VCR); 3) diagnosis to treatment (n=34,525, 10% under 50; Victorian Radiotherapy Minimum Dataset, VAED and VCR).

Procedures: Intervals were analysed using descriptive statistics and compared using the Mann-Whitney U test.

Results: Time from presentation to diagnosis for younger and older adults was a median 43 days (Interquartile range [IQR]: 18.5 – 148.5) vs 54.5 days (IQR: 19 – 144), respectively p=0.618. Time from referral to colonoscopy for younger and older adults was a median 57 days (IQR: 21 – 134) vs 62 days (IQR: 29 – 124), respectively p=0.070. Median time from diagnosis to treatment was identical, 27 days (IQR: 12 – 46) for younger adults and 27 days (IQR: 12 – 47) for older adults, p=0.269.

Conclusions and clinical implications: Intervals from presentation to treatment of colorectal cancer were not prolonged for younger compared to older adults. Future research should explore the period from experiencing symptoms to presentation, symptom profiles, emergency presentations, and tumour characteristics to further understand advanced stage in younger adults.