We have had an opportunity to determine estrogen receptor (ER) in cytoplasmic fractions of primary breast cancer specimens taken from 79 patients under a fluorescent microscope using fluorescent estradiol conjugate as a tracer. In this study, an estrogen receptor is reported as positive when not less than 10% of carcinoma cells incorporate fluorescent estradiol conjugate into cytoplasma.
The ER positive rate was 61% in the total cases, varying by age: 70% in 40s and younger, 43% in 50s, and 60% in 60s and older patients.
Sixty-eight % of premenopausal breast cancers conpared to 54% of postmenopausal ones were ER positive.
Broken down by the histological type, the rates were 70% in papilla-tubular carinoma, 59 % in medullary tubular carcinoma, and 57 % in scirrhous type.
The rates by tumor size according to the clinical TNM classification were 70 % in T1, 59% in T2, 91% in T3, and 34% in T4.
The rates by stage difined by the pathological TNM classification were 65 % in Stage I, 50% in Stage II, 87% in Stage III, and 45% in Stage IV.
We discuss our findings and review others, as well.