Format

Send to

Choose Destination
Ann Surg Oncol. 2016 May;23(5):1522-9. doi: 10.1245/s10434-015-5030-1. Epub 2015 Dec 29.

Impact of Tumor Size on Probability of Pathologic Complete Response After Neoadjuvant Chemotherapy.

Author information

1
Department of Surgery, Breast and Melanoma Specialists of Charleston, Charleston, SC, USA. baronpl@gmail.com.
2
Department of Surgery, Dallas Surgical Group, Dallas, TX, USA.
3
Department of Biostatistics, Levine Cancer Institute, Charlotte, NC, USA.
4
Department of Surgery, Virginia Breast Center, Bon Secours Cancer Institute, Richmond, VA, USA.
5
Department of Surgery, The Breast Place, Charleston, SC, USA.
6
Department of Surgery, Blue Ridge Cancer Care, Roanoke, VA, USA.
7
Department of Surgery, Coastal Carolina Breast Center, Murrells Inlet, SC, USA.
8
Department of Surgery, Northeast Georgia Medical Center, Gainesville, GA, USA.
9
Department of Surgery, Comprehensive Cancer Center, Palm Springs, CA, USA.
10
Department of Surgery, Akron General Hospital, Akron, OH, USA.
11
Department of Medical Affairs, Agendia Inc, Irvine, CA, USA.
12
Department of Surgery, Breast Care Specialists, Allentown, PA, USA.
13
Department of Surgery, Virginia Hospital Center, Arlington, VA, USA.
14
Department of Surgery, Nashville Breast Center, Nashville, TN, USA.

Abstract

BACKGROUND:

The prospective Neoadjuvant Breast Symphony Trial (NBRST) study found that MammaPrint/BluePrint functional molecular subtype is superior to conventional immunohistochemistry/fluorescence in situ hybridization subtyping for predicting pathologic complete response (pCR) to neoadjuvant chemotherapy. The purpose of this substudy was to determine if the rate of pCR is affected by tumor size.

METHODS:

The NBRST study includes breast cancer patients who received neoadjuvant chemotherapy. MammaPrint/BluePrint subtyping classified patients into four molecular subgroups: Luminal A, Luminal B, HER2 (human epidermal growth factor receptor 2), and Basal type. Probability of pCR (ypT0/isN0) as a function of tumor size and molecular subgroup was evaluated.

RESULTS:

A total of 608 patients were evaluable with overall pCR rates of 28.5 %. Luminal A and B patients had significantly lower rates of pCR (6.1 and 8.7 %, respectively) than either basal (37.1 %) or HER2 (55.0 %) patients (p < 0.001). The probability of pCR significantly decreased with tumor size >5 cm [p = 0.022, odds ratio (OR) 0.58, 95 % confidence interval (CI) 0.36, 0.93]. This relationship was statistically significant in the Basal (p = 0.026, OR 0.46, 95 % CI 0.23, 0.91) and HER2 (p = 0.039, OR 0.36, 95 % CI 0.14, 0.95) subgroups. In multivariate logistic regression analyses, the dichotomized tumor size variable was not significant in any of the molecular subgroups.

DISCUSSION:

Even though tumor size would intuitively be a clinical determinant of pCR, the current analysis showed that the adjusted OR for tumor size was not statistically significant in any of the molecular subgroups. Factors significantly associated with pCR were PR status, grade, lymph node status, and BluePrint molecular subtyping, which had the strongest correlation.

PMID:
26714960
PMCID:
PMC4819747
DOI:
10.1245/s10434-015-5030-1
[Indexed for MEDLINE]
Free PMC Article

Supplemental Content

Full text links

Icon for Springer Icon for PubMed Central
Loading ...
Support Center