No abstract

Neoadjuvant chemotherapy is given more frequently to black, Hispanic, and Asian women than to white women. Black women have a lower likelihood of pCR for triple-negative and HER2-positive breast cancer. Whether this is due to biologic differences in chemosensitivity or to treatment or socioeconomic differences that could not be adjusted for is unknown.

Background: Complete pathological response following neoadjuvant chemotherapy for breast cancer indicates an excellent prognosis and may influence subsequent local or systemic treatment. However it is not clear which patients should undergo neoadjuvant chemotherapy. Methods: The National Cancer Database is a joint project of the Commission on Cancer of the American College of Surgeons and the American Cancer Society and contains about 80% of the cancer cases in the United States. Patients undergoing neoadjuvant chemotherapy for breast cancer in 2010 and 2011 were identified and the pathological response was compared across multiple demographic and tumor associated variables. Complete pathological response (pCR) was defined as no invasive cancer remaining in the breast or lymph nodes at the time of subsequent surgery. Results: Out of 334,447 cases of breast cancer diagnosed in 2010 and 2011, 29,534 (8.8%) underwent neoadjuvant chemotherapy. This included 2052 (6.9%) who also received neoadjuvant hormonal therapy and 616 (2.1%) who also received neoadjuvant radiation therapy. The pathological response was known for 19,310 (65%) and 6244 (32%) had a complete response (pCR), 11,522 (60%) had a partial response, and 1544 (8%) had no response. In logistic regression analysis, demographic and tumor related variables were significant (p<0.05) in both univariable and multivariable models. Estimated odds ratio of having pCR and p-values of demographic and tumor related variables are shown in Table 1, where a multivariable logistic regression was used to fit the data of 15686 patients. Conclusions: These data can be used to construct a nomogram that estimates the chance of pCR based on patient age, tumor histology, grade, molecular type, clinical T stage, and clinical N stage. This may be useful to help select suitable candidates for neoadjuvant chemotherapy. Predictors of Complete Pathological Response : Multivariate Logistic RegressionNOR95% CIp valueAge> 508500Reference<0.001< 5071861.271.19 - 1.37<0.001HistologyDuctal12,926Reference<0.001Lobular8370.650.52 - 0.80<0.001Mixed ductal/lobular5770.710.57 - 0.890.003Other13460.820.72 - 0.940.003Grade1872Reference<0.001252221.090.90 - 1.330.363395921.761.45 - 2.13<0.001Molecular typeER/PR+, Her2-6738Reference<0.001ER/PR+, Her2+26622.622.37 - 2.90<0.001ER/PR-, Her2+17574.033.58 - 4.53<0.001ER/PR-, Her2-45292.322.12 - 2.55<0.001Clinical T stageT12147Reference<0.001T271670.710.64 - 0.79<0.001T335130.480.43 - 0.54<0.001T428590.500.44 - 0.57<0.001Clinical N stageN05713Reference<0.001N173070.770.72 - 0.84<0.001N216460.680.60 - 0.78<0.001N310200.700.60 - 0.82<0.001 Citation Format: Vicky Q Yang, Gang Han, Sarah S Mougalian, Brigid K Killelea, Nina Horowitz, Anees B Chagpar, Brandon Hayse, Lajos Pusztai, Donald R Lannin. Predictors of complete pathological response to neoadjuvant chemotherapy for breast cancer: 19,310 cases from the national cancer database treated in 2010 and 2011 [abstract]. In: Proceedings of the Thirty-Seventh Annual CTRC-AACR San Antonio Breast Cancer Symposium: 2014 Dec 9-13; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2015;75(9 Suppl):Abstract nr P3-11-02.