INTRODUCTIONPatients with primary breast cancer (PBC) are at 2 to 6 times higher risk for developing synchronous and metachronous breast cancer (MBC). The pathology and behavior of MBC still remains unclear.METHODSWe reviewed the charts of 108 women with MBC at our hospital over the past 10 years. Profile patterns of the estrogen receptor (ER), the progesterone receptor (PR), and Her2/neu receptors were explored.RESULTSOf 33 patients with ER(+)/PR(+) in the primary tumor, 23 (70%) retained the status in MBC. Forty-five (92%) of 49 patients with ER(-)/PR(-) in the primary tumor remained the same in MBC. Most Her2(-) tumors (22/31, 71%) remained negative, but 50% (8/16) of Her2(+) tumors became negative.CONCLUSIONSMost MBC retained the ER/PR expression patterns irrespective of the treatment for the primary tumor, thus suggesting a common origin. Because MBCs tend to be triple negative and thus more aggressive, early detection and close surveillance techniques must be devised.