Breast Ductal Lavage for Assessment of Breast Cancer Biomarkers

Abstract

Purpose Lavage of the ductal systems of the breast provides fluid (DLF) containing hormones and products of hormone actions that may represent more accurately the composition of the breast than samples collected from blood or urine. The present study was undertaken to assess the presence of potential cancer biomarkers, their variation among individuals at high risk for breast cancer, and differences associated with menopause and tamoxifen treatment. Methods Seventy seven tamoxifen-eligible subjects with a 5-year breast cancer risk estimate (Gail > 1.6%)(N = 53) or recently diagnosed breast cancer (N = 24) were offered tamoxifen therapy; those not accepting tamoxifen were under observation only. After six months, all subjects underwent ductal lavage (DL) in an unaffected breast. Estradiol (E2), estrone sulfate, androstenedione, dehydroepiandrosterone (DHEA), DHEA sulfate, progesterone, cathepsin D and epidermal growth factor (EGF) were measured in DLF by immunoassays. Data were expressed as the mass of analyte per mg of protein in DLF and normalized by natural log transformation. Results With the exception of DHEA, none of the analytes measured were significantly lower in postmenopausal women than in premenopausal women. The mean loge concentration difference in estradiol was 10.9%. Tamoxifen treatment for 6 months did not result in a significantly greater concentration of E2 or in any of the other analytes in DLF of pre- or postmenopausal women. The between-duct variance of the concentration of free steroids within the same breast averaged 51% less than that between subjects, and was similar to that of non-diffusible proteins. Conclusions The maintenance of estradiol concentrations in the breast after menopause demonstrates the importance of local biosynthesis. The fact that DLF E2 does not reflect the high serum concentrations of E2 during tamoxifen treatment indicates that breast concentrations of estradiol may be under feedback control. Unlike studies of low risk populations, progesterone concentrations were not significantly less in postmenopausal than in premenopausal women. The similarity in variance of free steroids and protein analytes between ducts of a breast indicates little transfer of steroids between lobules.

Methodological considerations in estrogen assays of breast fluid and breast tissue

“…However, in a recent study [10], we were able to obtain adequate samples from only 86.3% of subjects. Even when fluid was obtained, no protein was found in 7.3% of samples.…”

“…The methods for collection of NAF and DLF have been described in detail in previous publications [9,10]. Briefly, after warming and massage of the breast, droplets of NAF are collected from the nipple in calibrated capillary tubes.…”

“…The volume is measured, the sample is flushed out with 200 lL of phosphate-buffered saline, and the diluted sample is sealed and stored at À80°C. Lavage for DLF was performed as described previously [10]. The breast was massaged, and the Cytyc aspirator (Cytyc Corp., Boxborough, MA) was used to elicit nipple aspirate fluid.…”

“…1. Distribution of estradiol values in nipple aspirate samples [10]. Values in the upper graph are shown as number of subjects with values in increments of 8 pg/ml.…”

Evaluation of Factors Associated with Pain Experienced during Mammary Ductoscopy

“…With this technology, surgeons can easily locate the discharging duct or perform early-stage tumor screening for outpatients. Although duct lavage specimens used for malignancy screening by fluorescence or endocrine biomarkers are currently being researched [3,4,5,6], mammary ductoscopy is a useful and well-established tool for the examination of nipple discharge by visualization biopsy [7] and for guiding purposes [8]. The examination is non-invasive, and most patients can complete the entire examination based on 3 dimensions of the breast duct [9,10]; the most common complaint, however, is the pain experienced during the procedure.…”