Prognosis, Prognostic Factors and Predictive Factors in Centimeter or Subcentimeter Node-negative Breast Cancer

Because of mammography screening increasingly more women are diagnosed with centimeter or subcentimeter node-negative breast cancer (i.e., T1abN0); these tumors account for approximately 19% of all newly diagnosed breast cancers in Sweden. Although the long term relapse-free survival rates among patients with such tumors is as high as ≥90%, some reports suggest that certain patient subgroups may have rates <75%. Firmly established prognostic and predictive factors for patients with T1abN0 tumors are, however, lacking. This is a nationwide, register-based cohort study investigating prognostic and predictive factors in women with centimeter or subcentimeter breast cancer. The study hypotheses are: 1) Established prognostic and/or predictive factors in overall breast cancer are prognostic and/or predictive factors also in centimeter or subcentimeter node-negative breast cancer; 2) The established relative reduction in risk of recurrence and death of adjuvant treatment for overall breast cancer are similar in centimeter or subcentimeter node-negative breast cancer.