Biology and Clinical Implications of Fecal Occult Blood Test Screen-Detected Colorectal Cancer

Shehara Mendis; Wei Hong; Sumitra Ananda; Ian Faragher; Ian Jones; Matthew Croxford; Malcolm Steel; Azim Jalali; Grace Gard; Yat Hang To; Margaret Lee; Suzanne Kosmider; Rachel Wong; Jeanne Tie; Peter Gibbs

doi:10.1093/jncics/pkab100

Biology and Clinical Implications of Fecal Occult Blood Test Screen-Detected Colorectal Cancer

JNCI Cancer Spectr. 2022 Jan 5;6(1):pkab100. doi: 10.1093/jncics/pkab100.

Authors

Shehara Mendis^{1

2}, Wei Hong^{1

3}, Sumitra Ananda^{1

2

4}, Ian Faragher⁵, Ian Jones^{6

7}, Matthew Croxford⁵, Malcolm Steel⁸, Azim Jalali^{1

2}, Grace Gard^{1

2}, Yat Hang To^{1

3}, Margaret Lee^{1

2

9

10}, Suzanne Kosmider², Rachel Wong^{1

9

10}, Jeanne Tie^{1

2

3}, Peter Gibbs^{1

2

3

11}

Affiliations

¹ Personalised Oncology Division, Walter & Eliza Hall Institute, Parkville, VIC, Australia.
² Department of Medical Oncology, Sunshine Hospital, Western Health, St Albans, VIC, Australia.
³ Faculty of Medicine & Health Sciences, The University of Melbourne, Parkville, VIC, Australia.
⁴ Department of Medical Oncology, Peter MacCallum Cancer Centre, Parkville, VIC, Australia.
⁵ Department of Colorectal Surgery, Footscray Hospital, Western Health, Footscray, VIC, Australia.
⁶ Department of Colorectal Surgery, The Royal Melbourne Hospital, Parkville, VIC, Australia.
⁷ Department of Surgery, The University of Melbourne, Parkville, VIC, Australia.
⁸ Department of Colorectal Surgery, Box Hill Hospital, Eastern Health, Box Hill, VIC, Australia.
⁹ Department of Medical Oncology, Eastern Health, Box Hill, VIC, Australia.
¹⁰ Eastern Health Clinical School, Monash University, Box Hill, VIC, Australia.
¹¹ Department of Medical Oncology, The Royal Melbourne Hospital, Parkville, VIC, Australia.

Abstract

Background: Fecal occult blood test (FOBT)-based screening for colorectal cancer (CRC) reduces mortality, with earlier stage at diagnosis a prominent feature. Other characteristics of FOBT screen-detected cancers and any implications for clinical management have not been well explored.

Methods: We examined a multisite clinical registry to compare the characteristics and outcomes of FOBT screen-detected CRC via the Australian National Bowel Cancer Screening Program (NBCSP), which is offered biennially to individuals aged 50-74 years, and age-matched non-screen-detected CRC in the same registry. All statistical tests were 2-sided. Odds ratios (ORs) were calculated using the Baptista-Pike method, and hazard ratios via the log-rank method.

Results: Of 7153 registry patients diagnosed June 1, 2006, to June 30, 2020, 4142 (57.9%) were aged between 50 and 74 years. Excluding 406 patients with non-NBCSP screen-detected cancers and 35 patients with unknown method of detection, 473 (12.8%) were screen detected via the NBCSP, and 3228 (87.2%) were non-screen detected. Screen-detected patients were younger (mean age = 62.4 vs 64.2 years; P < .001) and more medically fit (OR for ASA score 1-2 = 1.91, 95% confidence interval [CI] = 1.51 to 2.41; P < .001). Pathologic characteristics within each stage favored the screen-detected patients. Stage III screen-detected colon cancers were more likely to receive adjuvant therapy (OR = 3.58, 95% CI = 1.52 to 8.36; P = .002). Screen-detected patients had superior relapse-free (hazard ratio = 0.41, 95% CI = 0.29 to 0.60; P < .001) and overall survival (hazard ratio = 0.22, 95% CI = 0.15 to 0.35; P < .001), which was maintained in matched stage comparisons and multivariable analysis.

Conclusions: Beyond stage at diagnosis, multiple other factors associated with a favorable outcome are observed in FOBT screen-detected CRC. Given the substantial stage-by-stage differences in survival outcomes, if independently confirmed, individualized adjuvant therapy and surveillance strategies could be warranted for FOBT screen-detected cancers.

MeSH terms

Australia / epidemiology
Biology
Colonic Neoplasms*
Colorectal Neoplasms* / diagnosis
Early Detection of Cancer / methods
Humans
Neoplasm Recurrence, Local
Occult Blood