The DNA labelling index: a prognostic factor in node-negative breast cancer

Area of Science:

• Oncology
• Cell Biology
• Cancer Research

Background:

• Assessing prognostic factors in early-stage breast cancer is crucial for treatment decisions.
• The DNA labelling index (LI), a measure of S-phase fraction, reflects cell proliferation.
• Previous prognostic indicators for node-negative (N-) breast cancer require further validation.

Purpose of the Study:

• To evaluate the prognostic value of the DNA labelling index (LI) in node-negative (N-) breast cancer patients.
• To determine if LI can predict metastatic potential and survival outcomes.
• To compare LI's efficacy against other established prognostic factors.

Main Methods:

• Retrospective analysis of 76 N- breast cancer patients operated between 1975-1979.
• Patients were stratified into two groups based on median DNA labelling index (LI).
• Comparison of survival and recurrence rates between high LI and low LI groups, controlling for age, tumor size, and receptor status.

Main Results:

• Higher LI correlated with a greater frequency of grade 3 tumors.
• Patients with high LI showed significantly lower 8-year survival (36% vs 100%) and relapse-free survival (56% vs 83%).
• Metastases occurred earlier in the high LI group, with 2-year survival rates of 75% versus 100%.

Conclusions:

• The DNA labelling index (LI) is a significant prognostic factor for metastatic potential in N- breast cancer.
• LI demonstrated superior prognostic value compared to tumor size, histological grade, or hormone receptor status.
• Identifying high-risk patients via LI may enable targeted adjuvant medical treatment to improve outcomes.