Adapting to changing risks

Colorectal cancer staging can be misleadingly optimistic: a tumour may be classified as stage 2 even at T4 (tumour growth into nearby structures), although with such T a classification well over half of these lesions are associated with local or distant spread. Ideally, detection should happen at in-situ, T1, or T2 stages, before the risk of distant metastasis increases.

This raises the question: why aren’t these cancers detected earlier? Symptoms such as changes in bowel habits, abdominal discomfort, anaemia, and rectal bleeding are often nonspecific and can be misattributed to less serious conditions like haemorrhoids or dietary issues. For a healthy 40-year-old, these signs may not immediately raise alarm, leading to significant delays in diagnosis. Studies indicate that the median time from symptom onset to diagnosis ranges from 4.8 to 9.7 months, even among individuals presenting multiple warning signs.[5] This delay contributes to a higher likelihood of advanced-stage disease at diagnosis, underscoring the need for heightened public awareness and updated screening protocols. Emerging evidence also suggests that early-onset colorectal cancers may be more aggressive in nature, further reinforcing the urgency of earlier detection.

Risk factors & underwriting

Underwriting colorectal cancer risk involves assessing known factors such as inflammatory bowel disease (Crohn’s, colitis), previous polyps, unexplained anaemia or blood loss, and digestive symptoms like unexplained weight loss or abdominal pain. Many risk factors remain unknown or are not routinely captured in underwriting or medical records. Lifestyle factors like exercise and diet are important but challenging to incorporate into underwriting decisions.

A review was conducted of over 100 unique claims for colorectal cancer in individuals under 50, across life, critical illness, and total permanent disability policies, all paid within the last five years. Nearly two-thirds of these claims were male, consistent with population data. Approximately 80% were non-smokers, 20% were smokers, though ex-smoker status was often unavailable. Alcohol consumption data was limited and often vague.

Six claims were paid within the first year, some within just three months. Diagnoses were frequently at an advanced stage, and 75% of claims were for critical illness policies. Many involved lymph node spread or metastases. While lockdowns may have contributed to delays, most patients sought medical help promptly, with GPs responding appropriately.

Surprisingly, none of the claimants reported a family history of bowel cancer at application, though some mentioned second-degree relatives at the claim stage. Emerging research linking family history of diabetes in men under 60 to colorectal cancer is worth further study. Regarding underwriting, one applicant with ulcerative colitis was rated accordingly; another was diagnosed after application. Notably, 80% of claims were accepted at standard rates. It appears that many of these diagnoses are sporadic.

Height & cancer risk

An interesting observation from the Hannover Re UK data science team is that the claimants were taller than average - many exceeding 6′, with the tallest reaching 6’8”. Exploring this further reveals a clear link between height and cancer risk. Although the lowest relative increase in risk is for colorectal cancer, that risk exists and is significant. A meta-analysis of 47 observational studies involving 280,644 CRC cases shows that colorectal cancer risk increases by approximately 14% for every 10 cm rise in height and about 10% for males and 16% for females per 10 cm increase. Individuals in the tallest height percentile face a 24% greater risk compared to those in the shortest percentile.[6] While this relative increase is lower than for some other cancers, the consistent significance across sexes and studies indicates it's a robust finding that should not be overlooked.

Physical activity offers benefits beyond supporting metabolic health: it positively alters microbiome diversity, improves gut transit, reduces exposure time to carcinogens, lowers systemic inflammation and oxidative stress, and enhances immune surveillance, collectively helping intercept abnormal cells before they develop into tumours.

While obesity exacerbates these issues – driving insulin resistance, systemic inflammation, visceral fat accumulation, and further microbial imbalance – the association between gut health and cancer risk is significant across all weight categories. Elevated BMI has been linked to a fourfold increased CRC risk in some populations, with even stronger effects observed in women. This data underscores the importance of maintaining gut and metabolic health for all individuals, regardless of BMI.