Variation in use of neoadjuvant chemotherapy in patients with stage III breast cancer: Results of the Dutch national breast cancer audit.

OBJECTIVES: Neoadjuvant chemotherapy (NAC) is important in the optimal treatment of patients with locally advanced (stage III) breast cancer (BC). The objective of this study was to examine the clinical practice of NAC for stage III BC patients in all Dutch hospitals participating in BC care. MATERIALS AND METHODS: All patients aged 18-70 years who received surgery for stage III BC from January 2011 to September 2015 were selected from the national multidisciplinary NABON Breast Cancer Audit. Multivariable logistic regression was used to assess independent predictors of NAC use, focussing on hospital factors. RESULTS: A total of 1230 out of 1556 patients with stage III BC (79%) received NAC prior to surgery. The use of NAC did not change over time. We observed a large variation of NAC use between hospitals (0-100%). Age <50 years, breast MRI, large tumour size, advanced nodal disease, negative hormone receptor status and hospital participation in neoadjuvant clinical studies were significant independent predictors of NAC use (all P < 0.001). NAC use in stage III BC was not influenced by hospital type and hospital surgical volume. After adjustment for all independent predictors, variation in NAC use between hospitals remained (0% to 97%). CONCLUSION: NAC was used in 79% of patients with stage III BC, which represent a high quality of care in the NL. Patient, tumour, clinical management and hospital factors could not explain considerable variation in its use between hospitals. Hospital participation in neoadjuvant studies did show to improve the use of NAC in daily practice.