Should the Breast Cancer Staging System be Revised?

Area of Science:

• Oncology
• Clinical Research
• Cancer Prognostics

Background:

• Stage T2N0 breast cancer encompasses tumors between 2-5 cm.
• Tumor size is a critical factor in breast cancer staging and prognosis.
• Differentiating outcomes based on tumor size within T2N0 is essential for treatment planning.

Purpose of the Study:

• To compare oncological outcomes between T2N0 breast cancer patients with tumor sizes <4 cm (T2a) and ≥4 cm (T2b).
• To determine if tumor size ≥4 cm is a negative predictor of prognosis in stage T2N0 breast cancer.

Main Methods:

• Retrospective analysis of 70,971 patients diagnosed with T2N0 breast cancer between 2010-2019 from the SEER 17 Research Plus database.
• Patients were categorized into two groups: T2a (<4 cm) and T2b (≥4 cm).
• Clinicopathological characteristics, overall survival (OS), and cancer-specific survival (CSS) were compared between groups.

Main Results:

• The T2a group exhibited significantly higher 5-year OS (87.2%) and CSS (93.7%) rates compared to the T2b group (OS: 80.8%, CSS: 89.4%).
• Univariate analysis showed a 1.53 times higher risk of death and a 1.69 times higher risk of cancer-specific death in the T2b group.
• Multivariate analysis confirmed a 1.38 times higher risk of death and a 1.42 times higher risk of cancer-specific death for T2b patients.

Conclusions:

• Stage T2b breast cancer patients (tumor size ≥4 cm) have significantly poorer overall survival and cancer-specific survival rates than T2a patients.
• Tumor size ≥4 cm is identified as a significant negative predictor of prognosis in T2N0 breast cancer.
• These findings underscore the importance of tumor size in stratifying risk and guiding treatment for T2N0 breast cancer.