Predictors of complete pathological response after neoadjuvant systemic therapy for breast cancer.
BACKGROUND
The aim of the current study was to identify predictors of pathologic complete response (pCR) following neoadjuvant therapy.


METHODS
From 2000 to 2007, 518 breast cancer patients received neoadjuvant therapy. Data were compared using chi(2) and Fisher's exact tests and multivariate analysis of variance, as appropriate.


RESULTS
Of 518 breast cancer patients receiving neoadjuvant therapy, 81 (16%) had pCR (77 of 456 [17%] with chemotherapy, 4 of 62 [6%] with endocrine therapy; P < .05). Four factors were associated with pCR: higher tumor grade (P = .015), lack of estrogen receptor (ER) and progesterone receptor (PR) expression (P < .0001), HER2/neu amplification (P = .025), and negative lymph node status (P < .0001). On multivariate analysis, ER and PR negativity, HER2/neu amplification, and negative lymph node status were found to significantly correlate with pCR.


CONCLUSIONS
Patients with ER-negative and PR-negative and HER2/neu-amplified breast cancer phenotypes are more likely to experience pCR to neoadjuvant therapy. Although pCR is more frequently observed following neoadjuvant chemotherapy, it is rare following neoadjuvant endocrine therapy.
Department of Surgery, Washington University School of Medicine, St. Louis, MO, USA.
Marcus C
MC
Tan
Fatema
F
Al Mushawah
Feng
F
Gao
Rebecca L
RL
Aft
William E
WE
Gillanders
Timothy J
TJ
Eberlein
Julie A
JA
Margenthaler
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000970:Antineoplastic Agents / Q000008:administration & dosage*; D001943:Breast Neoplasms / Q000188:drug therapy* / Q000378:metabolism / Q000473:pathology* / Q000601:surgery; D005260:Female; D006801:Humans; D008875:Middle Aged; D020360:Neoadjuvant Therapy; D012074:Remission Induction
D000970:Antineoplastic Agents