Abstract 2679
Background
Adjuvant! Online (AOL) and Nottingham Prognostic Index (NPI) are prognostic tools that are widely used to aid treatment decision-making. Although performing globally well, their performance is unclear in populations other than those used in their validation studies and particularly in specific subgroups such as women ≤ 40 years. The present study aimed to evaluate for the first time the prognostic performance of AOL and NPI in young early breast cancer patients.
Methods
This is a multicentre hospital-based retrospective cohort study including young (≤ 40 years) and older (55-60 years) breast cancer patients treated from January 2000 until December 2004 at 4 large Belgian and Italian institutions. Predicted 10-year overall survival (OS) and disease-free survival (DFS) using AOL and 10-year OS using NPI were calculated for every patient. To assess calibration, the trimmed mean of the predicted 10-year outcomes was compared to the observed (Kaplan-Meier estimate at 10 years) 10-year rates by using one-sample t-test. Discriminatory accuracy was assessed by calculating the area under the receiver-operator characteristic curve and the corresponding 95% confidence intervals for 10-year predicted OS and DFS. Vital status was cross-checked with the national registries in Belgium and Italy.
Results
A total of 1,283 patients were included (376 in the young and 907 in the older cohorts, respectively). AOL accurately predicted 10-year OS (absolute difference: 0.66%; p = 0.37) in the young cohort, but overestimated 10-year DFS by 7.66% (p = 0.003). In the older cohort, AOL significantly underestimated both 10-year OS and DFS, by 7.20% (p
Conclusions
In young breast cancer patients, AOL is a reliable tool in predicting OS at 10 years but not DFS, while the calibration performance of NPI is suboptimal. In patients aged 55-60 years, the role of AOL and NPI deserves further investigations.
Clinical trial identification
Not applicable
Legal entity responsible for the study
N/A
Funding
N/A
Disclosure
All authors have declared no conflicts of interest.