Was Breast Conserving Surgery Underutilized for Early Stage Breast Cancer? Instrumental Variables Evidence for Stage II Patients from Iowa

Abstract

If marginal patients are representative of patients whose treatment choices would be affected by changes in treatment rates, an increase in the breast conserving surgery plus irradiation rate for stage II early stage breast cancer patients would have decreased survival in Iowa during the early 1990s. Further research with newer data and broader samples is needed to make more current and specific assessments.