Discordance in early breast cancer for tumour grade, estrogen receptor, progesteron receptors and human epidermal receptor-2 status between core needle biopsy and surgical excisional primary tumour.

The aim of the present study was to compare the tumour grade, Estrogen Receptor (ER), Progesteron Receptor (PgR) and Human Epidermal Receptor-2 (HER-2) status in the core needle biopsy (CNB) with those observed in the subsequent excisional primary tumour (EPT). All patients diagnosed with an early breast cancer in our University Hospital Center between January 1, 2005 and December 31, 2006 were included but exclusion criteria of patients with large tumour requiring neoadjuvant chemotherapy and cases with more than one tumour (multicentricity/multifocality tumours). Histological tumour grade assessed according to Nottingham Grading System (SBRm), ER, Pgr and HER-2 tumoural status were assessed twice in CNB and in EPT. A total of 175 patients were assessed. The concordance between CNB and EPT for Grade, ER, PgR and HER2 status were 75.4% (p > 0.00001), 84% (p > 0.00002), 78.3% (p = 0.002) and 98.3% (p = 0.486) respectively. In conclusion CNB can be used with confidence for HER2 determination. For grade, PgR and ER due to substantial discordance results from CNB should be used with caution.