TY - JOUR
T1 - The role of postmastectomy radiotherapy in clinically nodepositive, stage II-III breast cancer patients with pathological negative nodes after neoadjuvant chemotherapy
T2 - An analysis from the NCDB
AU - Liu, Jieqiong
AU - Mao, Kai
AU - Jiang, Shuai
AU - Jiang, Wen
AU - Chen, Kai
AU - Kim, Betty Y.S.
AU - Liu, Qiang
AU - Jacobs, Lisa K.
PY - 2016/4/26
Y1 - 2016/4/26
N2 - Purpose: The role of postmastectomy radiotherapy (PMRT) in clinically nodepositive, stage II-III breast cancer patients with pathological negative nodes (ypN0) after neoadjuvant chemotherapy (NAC) remains controversial. Methods: A total of 1560 clinically node-positive, stage II-III breast cancer patients treated with NAC and mastectomy who achieved ypN0 between 1998 and 2009 in the National Cancer Database were analyzed. The effects of PMRT on overall survival (OS) for the entire cohort and multiple subgroups were evaluated. Imputation and propensity score matching were used as sensitivity analyses to minimize biases. Results: Of the entire 1560 eligible patients, 903 (57.9%) received PMRT and 657 (42.1%) didn't. At a median follow-up of 56.0 months, no statistical difference was observed for OS between two groups by univariate and multivariate analyses (P = 0.120; HR 1.571, 95% CI 0.839-2.943). On subgroup analyses, PMRT significantly improved OS in patients with clinical stage IIIB/IIIC disease, T3/T4 tumor, or residual invasive breast cancer after NAC (P < 0.05). This improvement in OS remained significant after sensitivity analyses for the propensity score-matched patients. Conclusions: This study demonstrated that PMRT showed a heterogeneous effect in clinically node-positive, stage II-III breast cancer patients with ypN0 following NAC. PMRT improved OS for patients with clinical stage IIIB/IIIC disease, T3/T4 tumor, or residual invasive breast tumor after NAC. In the absence of definitive conclusions from prospective studies, including the ongoing NSABP B-51 trial, our findings may help identify specific groups of women with clinically node-positive, stage II-III breast cancers who could benefit from PMRT after NAC.
AB - Purpose: The role of postmastectomy radiotherapy (PMRT) in clinically nodepositive, stage II-III breast cancer patients with pathological negative nodes (ypN0) after neoadjuvant chemotherapy (NAC) remains controversial. Methods: A total of 1560 clinically node-positive, stage II-III breast cancer patients treated with NAC and mastectomy who achieved ypN0 between 1998 and 2009 in the National Cancer Database were analyzed. The effects of PMRT on overall survival (OS) for the entire cohort and multiple subgroups were evaluated. Imputation and propensity score matching were used as sensitivity analyses to minimize biases. Results: Of the entire 1560 eligible patients, 903 (57.9%) received PMRT and 657 (42.1%) didn't. At a median follow-up of 56.0 months, no statistical difference was observed for OS between two groups by univariate and multivariate analyses (P = 0.120; HR 1.571, 95% CI 0.839-2.943). On subgroup analyses, PMRT significantly improved OS in patients with clinical stage IIIB/IIIC disease, T3/T4 tumor, or residual invasive breast cancer after NAC (P < 0.05). This improvement in OS remained significant after sensitivity analyses for the propensity score-matched patients. Conclusions: This study demonstrated that PMRT showed a heterogeneous effect in clinically node-positive, stage II-III breast cancer patients with ypN0 following NAC. PMRT improved OS for patients with clinical stage IIIB/IIIC disease, T3/T4 tumor, or residual invasive breast tumor after NAC. In the absence of definitive conclusions from prospective studies, including the ongoing NSABP B-51 trial, our findings may help identify specific groups of women with clinically node-positive, stage II-III breast cancers who could benefit from PMRT after NAC.
KW - Breast cancer
KW - Complete pathological nodal response
KW - Neoadjuvant chemotherapy
KW - Postmastectomy radiotherapy
KW - Survival benefit
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UR - http://www.scopus.com/inward/citedby.url?scp=84966671397&partnerID=8YFLogxK
U2 - 10.18632/oncotarget.6664
DO - 10.18632/oncotarget.6664
M3 - Article
C2 - 26709538
AN - SCOPUS:84966671397
SN - 1949-2553
VL - 7
SP - 24848
EP - 24859
JO - Oncotarget
JF - Oncotarget
IS - 17
ER -