The need to examine metastatic tissue at the time of progression of breast cancer: is re-biopsy a necessity or a luxury?
Knowledge of estrogen receptor (ER), progesterone receptor (PgR) and human epidermal growth factor receptor-2 (HER2) status is necessary for determining the optimal treatment of breast cancer patients. At the same time, the discordance between marker profiles (ER/PR and HER2) of primary and metastatic breast cancer is well documented. Whether discordant cases are secondary to "clonal selection" in the face of targeted anti-estrogen or anti-HER2 therapy or whether they are a laboratory artifact is still debated; both scenarios are likely. This article outlines current modalities for ER, PR, and HER2 testing in primary breast carcinoma and its metastases and reviews prospective and retrospective studies that have addressed these issues, as well as recent advances in the field.
Evelyn H. Lauder Breast and Imaging Center, Memorial Sloan-Kettering Cancer Center, 300 East 66th Street, New York, NY 10065, USA. mkhasraw@med.usyd.edu.au
Mustafa
M
Khasraw
Edi
E
Brogi
Andrew D
AD
Seidman
D001706:Biopsy / Q000379:methods; D001943:Breast Neoplasms / Q000378:metabolism / Q000473:pathology* / Q000628:therapy*; D018450:Disease Progression; D005260:Female; D006801:Humans; D011446:Prospective Studies; D018719:Erb-b2 Receptor Tyrosine Kinases / Q000032:analysis* / Q000378:metabolism; D011960:Receptors, Estrogen / Q000032:analysis* / Q000378:metabolism; D011980:Receptors, Progesterone / Q000032:analysis* / Q000378:metabolism; D012189:Retrospective Studies
D018719:Erb-b2 Receptor Tyrosine Kinases; D011960:Receptors, Estrogen; D011980:Receptors, Progesterone; C508053:ERBB2 protein, human