Serum lipids and apolipoproteins in women with breast masses.

BACKGROUND: Human mammary tissue metabolizes lipids from plasma, a process affected by female gonadal hormones. Both benign and malignant proliferation of breast tissue in women have been associated with changes in plasma lipid and lipoprotein levels.
METHODS: One hundred consecutive women with breast masses (50 malignant, 50 benign) had diagnostic biopsies followed by axillary node dissection in those with cancer. Fasting serum samples were taken just prior to biopsy and analyzed for lipid fatty acid and lipoprotein levels. Malignant breast tissue was analyzed for hormone receptor binding.
RESULTS: Low-density lipoprotein (LDL) components (total cholesterol, LDL-cholesterol, apolipoprotein B) were increased, but not significantly, in cancer patients compared to those with benign masses. Decreased levels of LDL-associated components were found in women with cancer recurrence by 3 years. Three apolipoproteins of high-density lipoprotein (apolipoprotein A-I, apolipoprotein A-II, apolipoprotein D) were more affected by the presence of breast masses than the lipids were. Fibrocystic disease, type of hormone binding, and recurrence within 3 years were significantly related to apolipoprotein changes, especially apolipoprotein D levels with hormone receptor binding and the apolipoprotein A-I/apolipoprotein B ratio with breast cancer recurrence.
CONCLUSIONS: Prior to diagnostic biopsy, serum lipid and apolipoprotein components of low-density lipoproteins were increased in women with fibrocystic disease and early stage cancer but decreased in women with early recurrence. However, apolipoprotein A-I, apolipoprotein A-II, and apolipoprotein D, of the high-density lipoproteins, were more affected than serum lipids. The ratio of apolipoprotein A-I to apolipoprotein B serum levels at time of biopsy was the best predictor of cancer recurrence.