Choosing Wisely in Rural America: Surgical Management of the Axilla in Elderly Patients with Clinically Node-negative, Hormone Receptor-positive Invasive Breast Cancer.

BACKGROUND: In 2016, the Choosing Wisely campaign published recommendations for patients older than 70 years with cT1-2N0 hormone receptor-positive (HR+)/human epidermal growth factor receptor 2-negative (HER2-) breast cancer, which stated that surgeons should avoid routine sentinel lymph node biopsy (SLNB) because it did not result in improved survival. The goal of this study was to determine whether rurality of the patient influenced the decision to adhere to this recommendation.

METHODS: This retrospective cohort study used the National Cancer Database Participant User Data File (PUF) to collect information from women older than 70 years with cT1-2N0, HR+/HER2- invasive breast cancer and compare demographic characteristics, tumor biology, and treatment (surgical management, radiotherapy [RT], and systemic therapy) of these women across the rural-urban continuum. A random forest model was used to determine what factors were associated with the likelihood of such women receiving SLNB.

RESULTS: The study included 1,802,124 women. Rural patients had significantly longer travel distances to treatment (P < 0.001) and were more likely to be treated at a community facility (P < 0.001), to undergo SLNB (P < 0.001), and to undergo both simple and modified radical mastectomy (P < 0.001) than their metropolitan counterparts. A random forest model indicated that the most important factors for predicting the probability of SLNB were age, T2 tumors, year of diagnosis, and facility type.

CONCLUSIONS: The study demonstrated that rurality may have an impact on compliance with recommendations, but this association may be mediated by underlying factors associated with rural care.