Colorectal Cancer Mortality Projections

Key Findings >

Question: Given currently available interventions, how far can we reduce colorectal cancer mortality?

Answer: Over the time frame of our study, we were able to see a nearly 50% reduction in CRC, from 19.9 deaths per 100,000 in 2002 to around 10.5 per 100,000 in 2020. A reduction of this magnitude would require increased effort in risk reduction, screening and chemotherapy. Maintaining current trends (which is an effort as well) will result in about a 40% reduction, to 11.9 deaths per 100,000 in 2020.


Detailed Description

How do we reduce colorectal cancer deaths?

  • By promoting a more healthy lifestyle – reducing risk factors such as smoking, obesity, lack of exercise, a diet rich in red meat, and folate deficiency.
  • By making sure more people are screened, either through a fecal occult blood test (FOBT) or endoscopy.
  • By extending the most effective chemotherapy to more patients.

Recent years have seen overall improvements in all three of these areas (although some risk factors are currently headed in the wrong direction), and we observe a corresponding decrease in the colorectal cancer death rate.

We modeled three scenarios based on differing assumptions about future trends in risk factors, screening and chemotherapy, which we term “upstream objectives", to project future mortality. The assumptions behind these scenarios are as follows:

  • Projected Trends (our baseline): trends in all upstream objectives continue at current rates for each race/sex group. Note that it may be difficult to sustain the pace of improvement in some areas.
  • Optimistic but Realistic: there is improvement over current trends in risk factors and screening, specific to each race/sex group, and the best currently-available chemotherapy is provided to all who might benefit.
  • Healthy People 2010 Goals met: risk factor and screening improve to applicable Healthy People 2010 (HP 2010) objectives and continue at the same rate as projected trends after 2010. These goals are across all race/sex groups, meaning that they will be harder to achieve for some groups than for others. Risk factors with no applicable Healthy People objectives continue at projected trends rates. Chemotherapy, which does not have a HP 2010 objective, meets the Optimistic but Realistic goal.

The following chart plots CRC mortality, as predicted by our models, for each scenario. If you hold your cursor over a point, you can see its value. Compared to 2002 (the latest year for which statistics were available when we performed our simulations) there is a 40% reduction by 2020 given the Projected Trends scenario, a 47% reduction under the Optimistic but Realistic scenario, and a 48% reduction under the Healthy People 2010 goals met scenario (calculated by dividing the mortality reduction by the 2002 mortality value).

Graphs showing the Both Races, Both Sexes results for the combined (average) model. The scenarios displayed are the the projected trends baseline, Risk Factors, Screening and Chemotherapy (Optimistic Goals) and Risk Factors, Screening and Chemotherapy* (HP 2010 Goals)

Download: data | image[D]

Looking at percent reductions from 2002 to 2020 by race/sex group, given optimistic, realistic assumptions about interventions, we find that the percent reduction ranges from from 50.1% for white males to 41.6% for black males, although the absolute reduction is greatest for  black males who face the highest CRC death rates. However, because of the very high rates of CRC deaths among black males this population group is the only one not to achieve the HP 2010 mortality objective even by 2020.

Colorectal Cancer Mortality in 2002 and 2020
given Optimistic but Realistic assumptions
Race/Sex Group CRC deaths per 100,000 % reduction from 2002
2002 2020
White Males
23.2
11.4
50.1
White Females
16.0
8.7
45.6
Black Males
33.4
19.5
41.6
Black Females
22.8
12.3
46.1

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