Background: The number of people living after a cancer diagnosis (complete prevalence) is increasing globally. In Italy, one million women will live in 2030 after a breast cancer diagnosis, and nearly half a million individuals after colorectal cancer. These people have complex and heterogeneous healthcare needs and raise new questions that are challenging to address using traditional descriptive epidemiology indicators (i.e., incidence, survival, mortality).
Objectives: Provide estimates of several different indicators of cancer cure able to represent distinct aspects of survivorship.
Methods: Breast and colorectal cancer cases diagnosed in 1997-2017 from the Italian network of cancer registries were selected to calculate the following cure indicators. Using survival mixture cure models, we estimated cure fraction, the proportion of newly diagnosed cases who will not die from cancer (i.e., cured patients); time to cure, defined as the time to reach a 5-year conditional net survival higher than 95%. By joining complete prevalence estimates and survival models results, we estimated cure prevalence, defined as the proportion of all prevalent cases who will not die of cancer. These three indicators were estimated using a documented, feasible and widely reproducible methodology that could be applied in other countries.
Results: For women with breast cancer aged<75 years, the cure fraction was 77% (>70% in all age groups), 99% for patients diagnosed at stage I, 84% at stage II, and 42% at stages III-IV. For colorectal cancer, cure fraction was 60% in men (64% in women), 91% (both sexes) at stage I, and 40% at stages III-IV.
In late 2017, 2.6% of all Italian women were alive after breast cancer and 87.5% will be cured and not die of breast cancer, 99.4% when diagnosed at stage I, 91.7% considering women diagnosed >5 years, 94.7% >10 years (i.e., the residual proportion of deaths for breast cancer was 5.3% after >10 years). People living after colorectal cancer were 422,407, 90.3% will not die of their disease (96.0% at stage I, 97.3% since >5 years, 99.0% since >10 years).
Time to cure was <10 years for colorectal cancer, regardless of sex, age, and stage. For women with breast cancer time to cure was ≤1 year after diagnosis at stage I (all ages) or stage II (age <65 years), whereas it was longer than 10 years for women with advanced breast cancer.
Conclusions: Cancer cure indicators can help characterise the long-term prognosis of survivors and accurately identify patients who are cured, having the same life expectancy as those who have not had cancer. Being classified as cured will improve the quality of life of survivors and support a return to work and social life. Moreover, they may help to personalise treatments/follow-up through risk stratification.
Finally, estimates of cancer cure indicators are essential to end discrimination against cancer survivors and to support the legal concept of the “right to be forgotten” in European countries.
 
* For details and members of the AIRTUM Working group, see:
Dal Maso et al IntJCancer 2024 doi:10.1002/ijc.34923 and
Guzzinati et al. ESMOOpen 2024 doi:10.1016/j.esmoop.2024.103635.

Percentage of people living after breast or colorectal cancer in Italy who will not die from cancer (CURE PREVALENCE), by stage of disease