pS2 expression and response to hormonal therapy in patients with advanced breast cancer.
Seventy-two patients with advanced breast carcinoma (42% bone, 25% visceral, 5.5% soft tissue, and 27.5% multiple site metastases) were evaluated to determine the relationship between tumor expression of the estrogen-regulated protein pS2, estrogen receptor (ER) or progesterone receptor (PgR) content, and response to hormonal therapy. Twenty-nine % of tumors were pS2 positive, 64% were ER positive, and 29% were PgR positive. Of the ER-positive patients (n = 43), 15 (35%) had greater than 10% of the invasive carcinoma which immunostained for pS2 (these were considered pS2 positive). Only 3 of 24 ER-negative tumors were pS2 positive. A weak association between pS2 expression and ER content (P = 0.08) but not PgR content was observed. Of pS2-positive patients, 52% had a partial or complete response to hormonal therapy. In 24% of pS2-positive patients the disease stabilized with treatment. In contrast, 27% of pS2-negative patients had a partial or complete response. In 10% of these patients the disease stabilized. Similar associations between therapeutic response and ER or PgR were not observed. The odds of having a clinical response to hormonal therapy was greater for pS2-positive than for ER- or PgR-positive tumors. pS2 expression may define a subset of ER-positive tumors that are more likely to respond to hormonal treatment.
Schwartz
L H
LH
Department of Radiation Therapy, Massachusetts General Hospital, Harvard Medical School, Boston 02114.
Koerner
F C
FC
Edgerton
S M
SM
Sawicka
J M
JM
Rio
M C
MC
Bellocq
J P
JP
Chambon
P
P
Thor
A D
AD
D014408:Biomarkers, Tumor / Q000032:analysis*; D001943:Breast Neoplasms / Q000737:chemistry / Q000473:pathology / Q000601:surgery / Q000628:therapy*; D005260:Female; D005474:Fluoxymesterone / Q000627:therapeutic use*; D006801:Humans; D009361:Neoplasm Invasiveness; D009362:Neoplasm Metastasis; D009363:Neoplasm Proteins / Q000032:analysis* / Q000096:biosynthesis; D009367:Neoplasm Staging; D011379:Prognosis; D011506:Proteins; D011960:Receptors, Estrogen / Q000032:analysis; D011980:Receptors, Progesterone / Q000032:analysis; D013629:Tamoxifen / Q000627:therapeutic use*; D000071163:Trefoil Factor-1; D025521:Tumor Suppressor Proteins
D014408:Biomarkers, Tumor; D009363:Neoplasm Proteins; D011506:Proteins; D011960:Receptors, Estrogen; D011980:Receptors, Progesterone; C051838:TFF1 protein, human; D000071163:Trefoil Factor-1; D025521:Tumor Suppressor Proteins; D013629:Tamoxifen; D005474:Fluoxymesterone