Abstract:
Objective To explore concordance between preoperative core needle biopsy (CNB) and resection specimen (RS) in evaluating biomarkers and molecular subtypes with immunohistochemical method.
Methods A retrospective study was performed on 324 breast cancer patients who underwent modified radical mastectomy at the Tianjin Medical University Cancer Institute and Hospital between August 2015 and November 2016. All patients who had received neoadjuvant systemic therapy were excluded. The aim of this analysis was to report concordance between CNB and surgical specimens in evaluating biomarkers, such as ER, PR HER-2, Ki-67, and molecular subtypes.
Results There was concordance between estrogen receptor (ER) assessment on CNB and RS in 94.1% (305/324) of the patients (κ=0.84). Concordance of the progesterone receptor (PR) and the human epidermal growth factor receptor 2 (HER-2) assessments were observed in 90.7% (294/324, κ=0.76) and 61.1% (198/324, κ=0.38) patients, respectively. Evaluation of Ki-67 revealed an accordance rate of 86.7% (281/324, κ=0.34), and the concordance for immunohistochemistry detection for assessing breast cancer (BC) molecular subtypes was 73.4% (91/124, κ=0.64).
Conclusions Although CNB showed good accuracy for evaluating hormonal receptor status and BC molecular subtypes, its evaluation of HER-2 and Ki-67 statuses was less accurate than other biomarkers. Therefore, we should combine immunohistochemical results with both CNB and RS samples in order to improve accuracy when diagnosing molecular subtypes. Moreover, improved diagnoses can provide the basis for more effective systemic therapies.