Colorectal and kidney cancer patients would see the greatest increase in their chances of survival if they were diagnosed at an earlier stage, data shows.
The four stages of cancer range from 1 (earliest stage) to 4 (latest stage) depending on the tumour size; whether the lymph nodes have cancer cells; or if the cancer has spread to other parts of the body.
Cancer patients with colorectal cancer have an overall net-survival of 59.1% (the survival of cancer patients compared to the general population) for the 5 years following diagnosis. At stage 1 this is 93.4%.
For patients with kidney cancer, overall net-survival is 63.3%, compared with 88.9% at stage 1.
While there are many factors that can influence a patient’s chance of surviving cancer, a major factor is the stage of the disease at diagnosis.
Earlier diagnosis would increase overall net-survival for all cancers but kidney and colorectal would benefit most from earlier diagnosis. This is due to the drop-off in net-survival in these cancers once diagnosed at stages 3 and 4, and the fact that overall net-survival lies between stages 3 and 4.
Overall net-survival for colorectal and kidney cancer falls between stages 3 and 4
5-year net-survival, by stage of diagnosis
Colorectal cancer has the largest difference in 5-year net survival between stages 1 and 4. People diagnosed with colorectal cancer at stage 1 are estimated to have a 93.4% net survival compared to 10.7% if diagnosed at stage 4 – a difference of 82.7 percentage points.
Men diagnosed at stage 1 prostate cancer have an estimated 100.5%1 5-year net survival compared to those diagnosed with stage 4 prostate cancer, which has a 47.7% 5-year net survival. This difference of 52.8 percentage points is the smallest in these estimates.
The earlier people are diagnosed, the higher their chances of survival
Proportion of people diagnosed at each stage, and overall net-survival
There tends to be higher overall 5-year net survival estimates for cancers that are mostly diagnosed at earlier stages, for example breast and prostate cancers. Meanwhile, there are generally lower 5-year net-survival estimates for cancers that are mostly diagnosed at a later stage, for example lung cancer.
While earlier diagnoses lead to better outcomes for cancer patients, some cancers are relatively asymptomatic which means they may not present with significant symptoms until the disease progresses, leading to patients going to the doctor later and consequently being diagnosed at later stages.
Typically, prostate cancer and breast cancer present specific symptoms (difficulty urinating, for prostate cancer, and a lump in the breast for breast cancer) which are well-publicised and lead people to seek health interventions. Additionally, these parts of the body are not considered vital organs and tumours can be removed relatively safely.
With other cancers this is not always the case. For instance, one symptom for colorectal cancer presents as stomach pain and discomfort, which could be applicable to any number of other conditions. Lung cancer (overall 5-year net survival of 15.3%) begins with a persistent cough and shortness of breath, which people may live with for a while before visiting a GP.
In the absence of obvious symptoms other conditions are ruled out first, during which time the cancer may have progressed to further stages. The government set a target in the Department for Health and Social Care's "Prevention is better than a cure" report for 75% of stageable tumours to be diagnosed by stage 1 or stage 2 by 2028.
This new data helps us understand more about how the stage of diagnosis affects health outcomes. It provides evidence for where health intervention resources should be concentrated and could help the government reach that target.
1: Estimates over 100% mean patients have more chance of living five years compared to the general population not diagnosed with cancer.