Hormonal determinants of nipple aspirate fluid yield among breast cancer cases and screening controls.
BACKGROUND
Nipple aspiration fluid (NAF) use as a biosample is limited by the variable yield across studies. We investigated the endocrine determinants of yield in an ongoing breast cancer case-control study.


METHODS
One-hundred and eighteen women yielding ≥2 μL NAF and 120 non-yielders were included; serum hormones were measured; differences in median hormones were assessed using the Wilcoxon rank-sum test. ORs and 95% confidence intervals (95% CI) for yielder status relative to hormone levels were estimated using logistic regression, adjusting for parity and lactation, and, in premenopausal women, menstrual cycle phase (MCP).


RESULTS
Prolactin concentrations were higher in yielders than non-yielders (premenopausal: 7.6 and 2.5 ng/mL, P < 0.01; postmenopausal 5.3 and 2.2 ng/mL; P < 0.01). Among premenopausal-yielders, estradiol was lower (64.3 vs. 90.5 pg/mL, MCP-adjusted P = 0.02). In separate menopausal status and parity-adjusted models, significant case-control differences persisted in prolactin: case OR 1.93 (95% CI, 1.35-2.77), control OR 1.64 (95% CI, 1.17-2.29). Premenopausal control yielders had higher progesterone (OR, 1.70; 95% CI, 1.18-2.46) and sex-hormone binding-globulin (OR, 2.09; 95% CI, 1.08-4.05) than non-yielders. Among parous women, further adjustment for lactation suggested a stronger positive association of serum prolactin with yield in cases than controls.


CONCLUSIONS
NAF-yielders show higher prolactin than non-yielders, regardless of menopause and parity; implications of this and other endocrine differences on NAF biomarkers of breast cancer risk deserve further study.


CONCLUSIONS
NAF yield is associated with a distinct endocrine environment that must be considered in studies of NAF-based breast cancer risk markers.
Authors' Affiliations: Departments of Preventive Medicine, Surgery, Radiology, Pathology, and Obstetrics and Gynecology, Feinberg School of Medicine and Robert H. Lurie Comprehensive Cancer Center of Northwestern University and Department of Pathology, University of Illinois at Chicago, Chicago, Illinois; and Epidemiology Research Program, American Cancer Society, Atlanta, Georgia.
Angela J
AJ
Fought
Claire
C
McGathey
Denise M
DM
Scholtens
Richard E
RE
Heinz
Rick
R
Lowe
Yvonne B
YB
Feeney
Oukseub
O
Lee
Thomas E
TE
Kmiecik
Judith A
JA
Wolfman
Charles V
CV
Clevenger
Peter H
PH
Gann
Susan
S
Gapstur
Robert T
RT
Chatterton
Seema A
SA
Khan
D000328:Adult; D000368:Aged; D001943:Breast Neoplasms / Q000097:blood / Q000378:metabolism*; D016022:Case-Control Studies; D055088:Early Detection of Cancer / Q000379:methods; D005260:Female; D006728:Hormones / Q000032:analysis* / Q000097:blood; D006801:Humans; D008875:Middle Aged; D055966:Nipple Aspirate Fluid / Q000737:chemistry* / Q000166:cytology
D006728:Hormones