Her2/neu expression predicts the response to antiaromatase neoadjuvant therapy in primary breast cancer: subgroup analysis from celecoxib antiaromatase neoadjuvant trial.
OBJECTIVE
Many studies suggest that Her2/neu play an important role in neoadjuvant endocrine therapy. This study aimed to determine whether the level of Her2/neu expression in advanced breast cancer changes after antiaromatase neoadjuvant treatment, as well as to identify the relationship between Her2/neu expression and response to this kind of therapy.


METHODS
Thirty-six postmenopausal patients with hormonal receptor-positive primary breast cancer were included in a study of three monthly cycles of neoadjuvant endocrine therapy with either Aromasin (25 mg daily) or Femara (2.5 mg daily). Immunohistochemistry (IHC) and fluorescence in situ hybridization (FISH) for Her2/neu were conducted both on pretreatment biopsies and surgical tumors.


RESULTS
Using IHC, 5 of 36 (13.9%) of the patients had a Her2/neu overexpression after treatment, as compared with 16 of 36 (44.4%) before. Meanwhile, there was no change in 21 (58.3%) patients, and through FISH, there was a change from amplification to no amplification in 15 (41.7%) patients. The response rate to the treatment was 75% for Her2/neu (+) tumors and 35% for Her2/neu (-) tumors (P = 0.017) while FISH was performed. The response rate was also significantly affected by the decrease in Her2/neu status after the treatment, with 73% of the tumors showing decreased Her2/neu expression and with 38% of the tumors showing no change of Her2/neu expression (P = 0.037).


CONCLUSIONS
Using both IHC and FISH, advanced breast cancers show statistical evidence of decreasing incidence of Her2/neu expression after antiaromatase neoadjuvant treatment. Our data also suggest that Her2/neu expression and its change during the treatment might be predictive markers for this kind of therapy.
Department of Surgery, The University of Hong Kong, Hong Kong, China.
Li
L
Zhu
Louis W C
LW
Chow
Wings T Y
WT
Loo
Xin-Yuan
XY
Guan
Mazakazu
M
Toi
D000368:Aged; D000369:Aged, 80 and over; D000730:Androstadienes / Q000627:therapeutic use; D000970:Antineoplastic Agents / Q000627:therapeutic use; D047072:Aromatase Inhibitors / Q000627:therapeutic use*; D001943:Breast Neoplasms / Q000235:genetics / Q000378:metabolism / Q000628:therapy*; D000068579:Celecoxib; D016861:Cyclooxygenase Inhibitors / Q000627:therapeutic use; D005260:Female; D015972:Gene Expression Regulation, Neoplastic; D006801:Humans; D007150:Immunohistochemistry; D017404:In Situ Hybridization, Fluorescence; D000077289:Letrozole; D008875:Middle Aged; D020360:Neoadjuvant Therapy; D009570:Nitriles / Q000627:therapeutic use; D011379:Prognosis; D011720:Pyrazoles / Q000627:therapeutic use; D018719:Erb-b2 Receptor Tyrosine Kinases / Q000032:analysis / Q000235:genetics*; D013449:Sulfonamides / Q000627:therapeutic use; D016896:Treatment Outcome; D014230:Triazoles / Q000627:therapeutic use
D000730:Androstadienes; D000970:Antineoplastic Agents; D047072:Aromatase Inhibitors; D000068579:Celecoxib; D016861:Cyclooxygenase Inhibitors; D000077289:Letrozole; D009570:Nitriles; D011720:Pyrazoles; D018719:Erb-b2 Receptor Tyrosine Kinases; D013449:Sulfonamides; D014230:Triazoles; C056516:exemestane