Response to primary chemotherapy in breast cancer patients with tumors not expressing estrogen and progesterone receptors.
BACKGROUND
We recently demonstrated that in premenopausal patients with estrogen receptors (ER)-absent tumors, early initiation of systemic chemotherapy after primary surgery might improve outcome. These data indicate a different responsiveness to chemotherapy for tumors not expressing hormone receptors. To test this hypothesis we evaluated the responsiveness to preoperative chemotherapy in patients with ER and progesterone receptors (PgR)-absent tumors.


METHODS
Patients with biopsy-proven T2-T3, N0-2 breast cancer treated at a single institution from January 1995 to August 1999 with preoperative chemotherapy were retrospectively evaluated. ER and PgR were determined immunohistochemically and classified for this purpose as absent (0% of the cells positive) or positive (> or = 1% of the cells).


RESULTS
On 117 evaluable patients 72 had an objective response (61%). A significant difference in response was observed for patients with ER and PgR absent compared with those with ER and/or PgR-positive tumors (82% vs. 57%, P = 0.03 Fishers's exact test). Pathological complete remission rates were also significantly different in the two groups (23% vs. 7%, respectively; P = 0.04).


CONCLUSIONS
The different degree of response according to hormone receptors expression supports the hypothesis that tumors not expressing both ER and PgR might represent a different clinical entity in terms of chemotherapy responsiveness.
Colleoni
M
M
Division of Medical Oncology, Istituto Europeo di Oncologia, Milan, Italy. marco.colleoni@ieo.it
Minchella
I
I
Mazzarol
G
G
Nolè
F
F
Peruzzotti
G
G
Rocca
A
A
Viale
G
G
Orlando
L
L
Ferretti
G
G
Curigliano
G
G
Veronesi
P
P
Intra
M
M
Goldhirsch
A
A
D000328:Adult; D000368:Aged; D000971:Antineoplastic Combined Chemotherapy Protocols / Q000627:therapeutic use*; D014408:Biomarkers, Tumor; D001943:Breast Neoplasms / Q000188:drug therapy / Q000503:physiopathology*; D005260:Female; D006801:Humans; D008875:Middle Aged; D017697:Premenopause; D011379:Prognosis; D011960:Receptors, Estrogen / Q000032:analysis* / Q000096:biosynthesis; D011980:Receptors, Progesterone / Q000032:analysis* / Q000096:biosynthesis; D012189:Retrospective Studies
D014408:Biomarkers, Tumor; D011960:Receptors, Estrogen; D011980:Receptors, Progesterone