Abstract 190P
Background
Young women with breast cancer (YWBC), defined by consensus as aged ≤40 years at diagnosis, are characterized by unique sociodemographic and clinical features. However, it is unclear if this definition is appropriate compared to other “young” age thresholds (e.g., ≤35 and ≤50 years).
Methods
Medical records of women aged ≤50 at BC diagnosis from 2010-2020 in a center in Monterrey, Mexico were reviewed. Clinicopathological features according to age group were compared with χ2 tests. The Kaplan-Meier method and Cox models were used to calculate recurrence-free survival (RFS) after excluding patients with stages 0 and IV.
Results
A total of 848 patients with a median follow-up of 35 months (95CI 32-38) were included. Younger patients had a higher incidence of node-positive and triple-negative disease (p<0.02) (Table). Notably, patients ≤35 yrs were not significantly different from those aged 36-40 except for an increased prevalence of a high tumor grade (58% v 44%; p=0.047). Unadjusted RFS at 2.5 yrs were 82% (95CI 71-89), 83% (95CI 75-89), 87% (95CI 81-91), and 85% (95CI 79-90) for patients ≤35, 36-40, 41-45, and 46-50 years, respectively. In a univariate analysis, age (continuous) was not associated with RFS (HR 0.99, 95CI 0.96-1.02). In a multivariate analysis adjusted for tumor size, nodal status, grade, and HR/HER2 status, none of the age groups showed a significantly different RFS (p>0.05). Only nodal invasion (HR 2.02, p=0.017), hormone-receptor (HR 0.44, p=0.001), and HER2 (HR 0.53, p=0.046) status were independent predictors of RFS. Table: 190P
Clinicopathological features shown as n (%). Missing values were omitted.
| Age | ≤35 yr | 36-40 yr | 41-45 yr | 46-50 yr | p |
| n | 107 | 172 | 268 | 301 | |
| Tumor size | 0.693 | ||||
| ≤2 cm | 16 (15) | 34 (20) | 53 (20) | 59 (20) | |
| >2 cm | 90 (85) | 138 (80) | 212 (80) | 233 (80) | |
| Nodal status | 0.016 | ||||
| N1-3 | 77 (73) | 120 (70) | 166 (62) | 172 (58) | |
| N0 | 29 (27) | 52 (30) | 101 (38) | 123 (42) | |
| Stage | 0.625 | ||||
| 0 | 3 (3) | 8 (5) | 9 (3) | 11 (4) | |
| I | 9 (8) | 16 (9) | 33 (12) | 42 (14) | |
| II | 40 (38) | 62 (36) | 114 (43) | 120 (40) | |
| III | 45 (42) | 73 (42) | 89 (33) | 99 (33) | |
| IV | 10 (9) | 13 (8) | 23 (9) | 26 (9) | |
| Grade | 0.119 | ||||
| 1-2 | 39 (42) | 78 (56) | 119 (52) | 133 (57) | |
| 3 | 53 (58) | 62 (44) | 109 (48) | 102 (43) | |
| Subtype | 0.011 | ||||
| HR+HER2- | 44 (42) | 91 (55) | 154 (60) | 161 (58) | |
| HR+HER2+ | 14 (13) | 17 (10) | 33 (13) | 31 (11) | |
| HR-HER2+ | 10 (10) | 16 (10) | 18 (7) | 37 (13) | |
| HR-HER2- | 36 (35) | 41 (25) | 50 (20) | 50 (18) |
Conclusions
In this study, young age at diagnosis was not associated with RFS. Therefore, the definition of YWBC should take into account other clinical, demographic, psychological, and behavioral features.
Clinical trial identification
Editorial acknowledgement
Legal entity responsible for the study
The authors.
Funding
Has not received any funding.
Disclosure
All authors have declared no conflicts of interest.