Adjuvant Treatment Decision-Making in Premenopausal Patients with EarlyStage Luminal A Breast Cancer

Breast cancer biomarkers have both prognostic and predictive value and play a crucial role in
determining individualized treatment strategies. The greatest therapeutic dilemma remains in
premenopausal patients with early-stage Luminal A breast cancer, particularly when deciding
between adjuvant chemotherapy and endocrine therapy, balancing the risk of overtreatment against
undertreatment.
These are two cases of 43-year-old premenopausal patients diagnosed with right-sided invasive ductal
carcinoma (pT1aN0M0, G3, Luminal A subtype). Both patients underwent mastectomy with axillary
dissection. Immunohistochemical analysis in both cases showed high estrogen (ER 80–85%) and
progesterone receptor expression (PR 90–95%), HER2-negative status (1+), Ki-67 of 15%, and negative
p53.
These cases highlight that multigene assays provide significant prognostic and predictive information
in selected patient populations. However, in resource-limited settings, careful evaluation of traditional
clinicopathological parameters remains essential for individualized treatment planning. Proper risk
assessment ensures optimal therapeutic decisions while avoiding unnecessary toxicity.