Neoadjuvant treatment for operable breast cancer in the community: Applications of cooperative group trials

Abstract

11529 Background: Neoadjuvant treatment for operable breast cancer is increasing based on clinical guidelines that are typically derived from randomized phase 3 cooperative group trials whose results establish a standard of care. However, the majority of cancer therapy is given in the community. There is controversy about the applicability of these studies to community practice. The National Surgical Adjuvant Breast and Bowel Project (NSABP) B-27 (JCO (24)2019–27, 2006) found the preoperative addition of four cycles of docetaxel to four cycles of AC significantly improved response rates in women with operable breast cancer. We studied whether community practice can achieve similar results in women with operable breast cancer treated in a neoadjuvant approach. Methods: Retrospective analysis of a cancer registry database from a community center consisting of 36 women with operable breast cancer who were treated preoperatively with four cycles of doxorubicin and cyclophosphamide followed by docetaxel was performed. Clinical and pathologic response to therapy was evaluated and compared to the peer-reviewed, published standard. Results: Of 36 patients reviewed, a total of 21 patients were identified for analysis. The average age of the patient was 54. The average tumor size was 6.4 cm, with 48% having estrogen receptor (ER) positive disease. The complete clinical response (CCR) was found to be 42.9% v 63.6%, p = 0.066; the partial clinical response (PCR) 38.1% v 27.1%, p = 0.320; the overall clinical response (CCR + PCR) 81.0 v 90.7; and the complete pathologic response (CPR) 23.8% v 26.1%, p = 1.00, compared to results published in NSABP B27, respectively. The data was tested against the standard as established by the NSABP B-27 by using the Fisher exact test. There were no significant differences between the two groups in regards to response rates. Sample size was too small to compare disease-free and overall survival. Conclusions: Although our sample contained a large proportion of ER positive tumors, women with operable breast cancer treated with four cycles of doxorubicin and cyclophosphamide followed by four cycles of docetaxel in the community setting achieve similar outcomes compared to national standards. Current breast cancer trials reflect community practice. No significant financial relationships to disclose.