Περίληψη:
Introduction: Associations of hormone-receptor positive breast cancer
with excess adiposity are reasonably well characterized; however,
uncertainty remains regarding the association of body mass index (BMI)
with hormone-receptor negative malignancies, and possible interactions
by hormone replacement therapy (HRT) use.
Methods: Within the European EPIC cohort, Cox proportional hazards
models were used to describe the relationship of BMI, waist and hip
circumferences with risk of estrogen-receptor (ER) negative and
progesterone-receptor (PR) negative (n = 1,021) and ER+PR+ (n = 3,586)
breast tumors within five-year age bands. Among postmenopausal women,
the joint effects of BMI and HRT use were analyzed.
Results: For risk of ER-PR- tumors, there was no association of BMI
across the age bands. However, when analyses were restricted to
postmenopausal HRT never users, a positive risk association with BMI
(third versus first tertile HR = 1.47 (1.01 to 2.15)) was observed. BMI
was inversely associated with ER+PR+ tumors among women aged <= 49 years
(per 5 kg/m(2) increase, HR = 0.79 (95%CI 0.68 to 0.91)), and
positively associated with risk among women >= 65 years (HR = 1.25 (1.16
to 1.34)). Adjusting for BMI, waist and hip circumferences showed no
further associations with risks of breast cancer subtypes. Current use
of HRT was significantly associated with an increased risk of
receptor-negative (HRT current use compared to HRT never use HR: 1.30
(1.05 to 1.62)) and positive tumors (HR: 1.74 (1.56 to 1.95)), although
this risk increase was weaker for ER-PR- disease (P-het = 0.035). The
association of HRT was significantly stronger in the leaner women (BMI
<= 22.5 kg/m(2)) than for more overweight women (BMI >= 25.9 kg/m(2))
for, both, ER-PR- (HR: 1.74 (1.15 to 2.63)) and ER+PR+ (HR: 2.33 (1.84
to 2.92)) breast cancer and was not restricted to any particular HRT
regime.
Conclusions: An elevated BMI may be positively associated with risk of
ER-PR- tumors among postmenopausal women who never used HRT.
Furthermore, postmenopausal HRT users were at an increased risk of
ER-PR- as well as ER+PR+ tumors, especially among leaner women. For
hormone-receptor positive tumors, but not for hormone-receptor negative
tumors, our study confirms an inverse association of risk with BMI among
young women of premenopausal age. Our data provide evidence for a
possible role of sex hormones in the etiology of hormone-receptor
negative tumors.
Συγγραφείς:
Ritte, Rebecca
Lukanova, Annekatrin
Berrino, Franco
Dossus,
Laure
Tjonneland, Anne
Olsen, Anja
Overvad, Thure Filskov
and Overvad, Kim
Clavel-Chapelon, Francoise
Fournier, Agnes and
Fagherazzi, Guy
Rohrmann, Sabine
Teucher, Birgit
Boeing,
Heiner
Aleksandrova, Krasimira
Trichopoulou, Antonia
Lagiou,
Pagona
Trichopoulos, Dimitrios
Palli, Domenico
Sieri, Sabina
and Panico, Salvatore
Tumino, Rosario
Vineis, Paolo
Ramon
Quiros, Jose
Buckland, Genevieve
Sanchez, Maria-Jose
Amiano,
Pilar
Chirlaque, Maria-Dolores
Ardanaz, Eva
Sund, Malin and
Lenner, Per
Bueno-de-Mesquita, Bas
van Gils, Carla H. and
Peeters, Petra H. M.
Krum-Hansen, Sanda
Gram, Inger Torhild and
Lund, Eiliv
Khaw, Kay-Tee
Wareham, Nick
Allen, Naomi E. and
Key, Timothy J.
Romieu, Isabelle
Rinaldi, Sabina
Siddiq,
Afshan
Cox, David
Riboli, Elio
Kaaks, Rudolf
