Clinicopathological features of breast cancer in women ≤35 years: A retrospective single-center study

Abstract

Objective: Although breast cancer (BC) predominantly affects women aged ≥ 50 years, its incidence among younger women is increasing. Younger patients often present with aggressive biological features. This study aimed to compare the clinicopathological characteristics and survival outcomes between BC patients aged ≤35 years and those >35 years. Materials and Methods: We retrospectively reviewed the data of 933 BC patients treated at Kocaeli University between 2006 and 2011. Patients were stratified by age (≤35 vs >35y). Demographics, tumor characteristics (TNM stage, grade, receptor status, lymph node involvement), and overall survival were analyzed. Results: Median age was 52 years (24-89). Of the total cohort, 6% were ≤ 35 years and 46% were premenopausal. Younger patients more frequently had T3 tumors (23% vs. 10%; p=0.049). However, no significant differences were observed regarding nodal status, histological grade, receptor expression, or survival (5-years OS 72% vs.74%, p=0.629). Each one-year increase in age was associated with an increased mortality risk (OR 1.04; 95% Cl, 1.02-1.06). Conclusion: While younger BC patients in our cohort presented more frequently with advanced T stage, their pathological features and survival rates were largely comparable across age groups. These results highlight importance of individualized management in young women and underscore the need for prospective studies to define age-specific prognostic and therapeutic implications.

Keywords

• breast cancer
• younger
• prognosis

References

1. Siegel RL, Kratzer TB, Giaquinto AN, Sung H,Jemal A. Cancer statistics, 2025. CA Cancer J Clin. 2025;75(1):10-45. doi: 10.3322/caac.21871
2. Sopik V. International variation in breast cancer incidence and mortality in young women. Breast Cancer Res Treat. 2021;186(2):497-507. doi: 10.1007/s10549-020-06003-8
3. Anders CK, Hsu DS, Broadwater G, et al. Young age at diagnosis correlates with worse prognosis and defines a subset of breast cancers with shared patterns of gene expression. J Clin Oncol. 2008;26(20):3324-30. doi: 10.1200/JCO.2007.14.2471
4. Zhu JW, Charkhchi P, Adekunte S, Akbari MR. What Is Known about Breast Cancer in Young Women? Cancers (Basel). 2023;15(6).doi: 10.3390/cancers15061917
5. Azim HA, Jr., Partridge AH. Biology of breast cancer in young women. Breast Cancer Res. 2014;16(4):427. doi: 10.1186/s13058-014-0427-5
6. Hao W, Rajendran BK, Cui T, et al. Advances in predicting breast cancer driver mutations: Tools for precision oncology (Review). Int J Mol Med. 2025;55(1). doi: 10.3892/ijmm.2024.5447
7. Paluch-Shimon S, Pagani O, Partridge AH, et al. ESO-ESMO 3rd international consensus guidelines for breast cancer in young women (BCY3). Breast. 2017;35:203-17. doi: 10.1016/j.breast.2017.07.017
8. Organization WHO. International Agency for Research on Cancer. 2025. http://irc.who.int

9. Colleoni M, Rotmensz N, Robertson C, et al. Very young women (<35 years) with operable breast cancer: features of disease at presentation. Ann Oncol. 2002;13(2):273-9. doi: 10.1093/annonc/mdf039
10. Dufour O, Houvenaeghel G, Classe JM, et al. Early breast cancer in women aged 35 years or younger: A large national multicenter French population-based case control-matched analysis. Breast. 2023;68:163-72. doi: 10.1016/j.breast.2023.02.004
11. Nixon AJ, Neuberg D, Hayes DF, et al. Relationship of patient age to pathologic features of the tumor and prognosis for patients with stage I or II breast cancer. J Clin Oncol. 1994;12(5):888-94. doi: 10.1200/JCO.1994.12.5.888
12. Goldhirsch A, Glick JH, Gelber RD, et al. Meeting highlights: international expert consensus on the primary therapy of early breast cancer 2005. Ann Oncol. 2005;16(10):1569-83. doi: 10.1093/annonc/mdi326
13. Partridge AH, Hughes ME, Warner ET, et al. Subtype-Dependent Relationship Between Young Age at Diagnosis and Breast Cancer Survival. J Clin Oncol. 2016;34(27):3308-14. doi: 10.1200/JCO.2015.65.8013
14. Conte B, Soldato D, Razeti MG, et al. De novo Metastatic Breast Cancer Arising in Young Women: Review of the Current Evidence. Clin Breast Cancer. 2022;22(1):78-87. doi: 10.1016/j.clbc.2021.10.001