AB056. SOH21AS189. The CTS5 score as a predictor of late distant recurrence: a systematic review and meta-analysis

Abstract

Background: The Clinical Treatment Score post-5 years (CTS5) integrates four clinicopathologic variables to estimate the residual disease recurrence risk in estrogen receptor-positive (ER+) breast cancer patients who have been treated with 5 years of adjuvant endocrine therapy (AET) and have remained distant recurrence free at 5 years post-diagnosis. This study aimed to determine the accuracy of the CTS5 in predicting actual distant recurrence rates. Methods: A systematic review was performed in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analysis statement. Studies relevant for inclusion in the current review were identified from The Cochrane Library, Ovid, PubMed, EMBASE. Results: Six papers reported on 35,089 post-menopausal patients (age range, 42–91) with a distribution risk as follows; 45.77% low risk, 29.98% intermediate risk, 24.25% high risk. The hazard ratio of distant recurrence within the high-risk group was 5.41 (CI: 4.50–6.51) relative to the lowrisk group. The intermediate group had a hazard ratio of 2.32 (CI: 1.90–2.84) relative to the low-risk group. Three papers reported on 10,425 pre-menopausal patients (age range, 18–54). The distribution of the CTS5 risk categories was as follows: 54.07% low risk, 23.85% intermediate risk, 22.08% high risk. The hazard ratio for the high-risk premenopausal cohort was 5.42 (CI: 2.26–13.01). The CTS5 as a continuous variable was significantly associated with increased distant recurrence in both the pre-menopausal (HR 1.36, CI: 1.15–1.60) and post-menopausal cohorts (HR 1.50, CI: 1.20–1.87). Conclusions: The CTS5 is predictive of the risk of late distant recurrence in preand postmenopausal ER+ breast cancer patients. The performance of the CTS5 score in different patient populations warrants further academic attention.