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Fig. 3. Kaplan-Meier curve for the OS of the BRCA1/2 Epirubicin HCl positive and negative
Fig. 4. Kaplan-Meier curve for the DFS of the VYWBC and YWBC groups.
with unfavourable biological markers, which portend a poor prognosis [27,41e43].
There are some limitations to our study, which are inherent to any retrospective cohort study. Although the VYWBC group received significantly more aggressive multimodality therapies, the
survival rates were worse than those in the YWBC group. Another limitation is the low rate of genetic testing, such as BRCA 1 or BRCA 2 mutations, and the lack of data on behavioural risk factors (e.g., physical activity, smoking, alcohol consumption, and use of hor-mone replacement therapy).
In conclusion, we found that the VYWBC group was not diag-nosed at a more advanced pT and pN category of disease compared with the YWBC group. The incidence of distant metastases was significantly higher in the VYWBC group. Tumours in the VYWBC group were characterized by more unfavourable biological pa-rameters (more likely a higher grade, ER-negative, PR-negative and a higher Ki67 value). Despite the more frequent use of chemo-therapy and endocrine therapy in the VYWBC group, the diagnosis of breast cancer at a younger age was associated with inferior OS and DFS rates. The VYWBC group presented a worse prognosis than the YWBC group. Our results support the concept that tumours developing in VYWBC are biologically different from tumours in YWBC and tend to be more aggressive with unfavourable biological markers, which portend a poorer prognosis. These results suggest that young women with breast cancer should be subgrouped into very young and young women populations. VYWBC should be regarded as higher-risk patients with a worse prognosis and decreased OS and DFS rates. VYWBC and YWBC, as different sub-groups, should be targeted by specialized multicentre clinical trials and further investigations.
Conflicts of interest
The authors have no conflicts of interest to declare.
Appendix A. Supplementary data
Please cite binding sites article as: Szollar A et al., A long-term retrospective comparative study of the oncological outcomes of 598 very young ( 35 years) and young (36e45 years) breast cancer patients, European Journal of Surgical Oncology, https://doi.org/10.1016/j.ejso.2019.06.007
A. Szollar et al. / European Journal of Surgical Oncology xxx (xxxx) xxx 7
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