Dietary and other risk factors in women having fibrocystic breast conditions with and without concurrent breast cancer: a nested case-control study in Shanghai, China.
Risk of breast cancer is increased in women with proliferative benign breast conditions. Most of these conditions, however, do not progress to breast cancer. The purpose of our study was to identify factors possibly associated with this progression. Women with proliferative fibrocystic breast conditions alone (214), and women with proliferative fibrocystic breast conditions and concurrent breast cancer (130), were compared to each other, and each of these groups of women were also compared to 1,070 controls; and 176 women with non-proliferative benign breast conditions alone, and 155 also with breast cancer, were similarly compared. All study subjects were selected from a cohort of women enrolled in a trial of breast self-examination in Shanghai. Women were interviewed to ascertain information on suspected risk factors for breast cancer and dietary habits. Conditional logistic regression was used to estimate adjusted odds ratios (OR) and 95% confidence intervals (CI). Increased risks of both proliferative fibrocystic breast conditions alone, and with breast cancer, were associated with low parity, a prior benign breast lump and breast cancer in a first-degree relative. Decreasing trends in the risk of both conditions with increasing intake of fruits and vegetables were observed. No factors were significantly associated with risk of breast cancer relative to risk of proliferative changes. Similar, but in some instances weaker, associations were observed for non-proliferative fibrocystic conditions with and without breast cancer. The possible risk or protective factors that were observed in our study most likely alter the risk of breast cancer at an early stage in the carcinogenic process, and probably do not alter risk of progression from proliferative fibrocystic breast conditions to breast cancer.
Li
Wenjin
W
Division of Public Health Sciences, Fred Hutchinson Cancer Research Center, Seattle, WA 98109, USA.
Ray
Roberta M
RM
Lampe
Johanna W
JW
Lin
Ming-Gang
MG
Gao
Dao Li
DL
Wu
Chunyuan
C
Nelson
Zakia C
ZC
Fitzgibbons
E Dawn
ED
Horner
Neilann
N
Hu
Yong Wei
YW
Shannon
Jackilen
J
Satia
Jessie A
JA
Patterson
Ruth E
RE
Stalsberg
Helge
H
Thomas
David B
DB
D000328:Adult; D001943:Breast Neoplasms / Q000150:complications / Q000209:etiology*; D016022:Case-Control Studies; D002681:China; D004032:Diet; D018450:Disease Progression; D005260:Female; D005348:Fibrocystic Breast Disease / Q000150:complications / Q000209:etiology*; D005638:Fruit; D006801:Humans; D008423:Maternal Age; D008875:Middle Aged; D010298:Parity; D012307:Risk Factors; D014675:Vegetables