Abstract
Background; Core needle biopsy (CNB) specimens have been widely used not only for the diagnosis of breast cancer, but
also for assessing biomarkers, including lymphovascular invasion (ly and v), nuclear grading, the estrogen receptor (ER), progesterone
receptor (PR), human epidermal growth factor receptor 2 (HER-2) and Ki-67. We herein compared the pathological biomarkers
of ER+/HER2- invasive breast cancers in CNB with those in the subsequent surgical specimens.
Methods; Patients with ER+/HER2- invasive breast cancer who presented to our department from August 2011 to July 2013
who had CNB and subsequent surgery were included. Lymphovascular invasion (ly, v) and nuclear grading were determined by
hematoxylin and eosin staining, and the ER, PgR, HER-2, and Ki-67 status were evaluated by immunohistochemistry.
Results; The concordance rates between CNB and surgical specimens for the ly, v, nuclear grading, ER and PgR were 2.4%,
2.9%, 63.0%, 96.4% and 82.1%, respectively. Lymphovascular invasion and nuclear grading tended to be underestimated with
CNB in discordant cases. The Ki-67 labeling index in CNB specimens was strongly correlated with that in surgical specimens
(correlation coefficient 0.75, p<0.0001). Consequently, there was a reasonable level of agreement between CNB and surgical
specimens for surrogate subtyping (82.1%).
Conclusions; CNB provided reliable information on the expression of hormone receptors, Ki-67 in ER+/HER2- invasive breast
cancers. However, because of the substantial discordance between CNB and surgical specimens, the status of lymphovascular
invasion and nuclear grading should not be concluded based on CNB specimens.
