Table 3.

Changes in HER2 status between primary breast and paired metastatic breast carcinomas according to hormonal receptor status

HR statusHER2 status
PBCNo. of patients (%)PBCNo. of patients (%)MBCP*
HER2– (%)HER2+ (%)
ER and/or PgR+82 (60)HER2–74 (66)64 (86)10 (14)0.002
HER2+8 (7)08 (100)
ER/PgR–55 (40)HER2–38 (69)36 (95)2 (5)0.68
HER2+17 (31)2 (12)15 (88)

Abbreviations: HR, hormonal receptor; PBC, primary breast cancer; MBC, metastatic breast cancer; ER, estrogen receptor; PgR, progesterone receptor; HER2−, score 0, 1+, 2+nonamplified; HER2+, score 2+amplified, 3+.

*Mc Nemar paired test.