Menstrual and reproductive factors, and hormonal contraception use: associations with non-Hodgkin lymphoma in a pooled analysis of InterLymph case-control studies.
BACKGROUND
The two most common forms of non-Hodgkin lymphoma (NHL) exhibit different sex ratios: diffuse large B-cell lymphoma (DLBCL) occurs more frequently in men and follicular lymphoma (FL) more frequently in women. Looking among women alone, this pooled analysis explores the relationship between reproductive histories and these cancers.


METHODS
Self-reported reproductive histories from 4263 women with NHL and 5971 women without NHL were pooled across 18 case-control studies (1983-2005) from North America, Europe and Japan. Study-specific odd ratios (ORs) and confidence intervals (CIs) were estimated using logistic regression and pooled using random-effects meta-analyses.


RESULTS
Associations with reproductive factors were found for FL rather than NHL overall and DLBCL. In particular, the risk of FL decreased with increasing number of pregnancies (pooled OR(trend) = 0.88, 95% CI 0.81-0.96). FL was associated with hormonal contraception (pooled OR = 1.30, 95% CI 1.04-1.63), and risks were increased when use started after the age of 21, was used for <5 years or stopped for >20 years before diagnosis. DLBCL, on the other hand, was not associated with hormonal contraception (pooled OR = 0.87, 95% CI 0.65-1.16).


CONCLUSIONS
Hormonal contraception is associated with an increased risk of FL but not of DLBCL or NHL overall.
Epidemiology and Genetics Unit, Department of Health Sciences, University of York, York, UK. Electronic address: eleanor.kane@egu.york.ac.uk.
E V
EV
Kane
Epidemiology and Genetics Unit, Department of Health Sciences, University of York, York, UK.
E
E
Roman
Division of Cancer Epidemiology German Cancer Research Centre, Heidelberg, Germany.
N
N
Becker
Division of Cancer Etiology, Department of Population Sciences, Beckham Research Institute of the City of Hope Duarte, USA.
L
L
Bernstein
Institute for Translational Epidemiology, The Tisch Cancer Institute, Mount Sinai School of Medicine, New York, USA; International Prevention Research Institute, Lyon, France.
P
P
Boffetta
Department of Epidemiology and Biostatistics, University of California at San Francisco, San Francisco.
P M
PM
Bracci
Department of Health Sciences Research, Mayo Clinic College of Medicine, Rochester.
J R
JR
Cerhan
Division of Biological Sciences, Department of Health Studies, University of Chicago, Chicago, USA.
B C-H
BC
Chiu
Occupational Health Section, Department of Public Health, University of Cagliari, Italy.
P
P
Cocco
Unit of Infections and Cancer (UNIC), Cancer Epidemiology Research Programme, IDIBELL, Catalan Institute of Oncology, Barcelona, Spain.
L
L
Costas
Cancer Epidemiology and Genetics, Masaryk Memorial Cancer Institute, Brno, Czech Republic.
L
L
Foretova
Department of Epidemiology and Biostatistics, University of California at San Francisco, San Francisco.
E A
EA
Holly
Istituto di Ricerche Farmacologiche 'Mario Negri' and Department of Occupational Medicine, Universitá degli Studi di Milano, Milan, Italy.
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C
La Vecchia
Aichi Cancer Center, Division of Epidemiology and Prevention, Nagoya, Japan.
K
K
Matsuo
Registre des Hemopathies Malignes de Cote d'Or, EA 4184, Faculte de Medecine de Dijon, Dijon, France.
M
M
Maynadie
Unit of Infections and Cancer (UNIC), Cancer Epidemiology Research Programme, IDIBELL, CIBERESP, Catalan Institute of Oncology, Barcelona, Spain.
S
S
Sanjose
Cancer Control Research Program, BC Cancer Agency, Vancouver, British Columbia, Canada.
J J
JJ
Spinelli
School of Public Health, Public Health University College, Dublin, Ireland.
A
A
Staines
Centro di Riferimento Oncologico, Aviano, Italy.
R
R
Talamini
Division of Cancer Etiology, Department of Population Sciences, Beckham Research Institute of the City of Hope Duarte, USA.
S S
SS
Wang
Yale University School of Public Health, New Haven, USA.
Y
Y
Zhang
Yale University School of Public Health, New Haven, USA.
T
T
Zheng
Sydney School of Public Health, The University of Sydney, Sydney, Australia.
A
A
Kricker
D016022:Case-Control Studies; D003278:Contraceptives, Oral, Hormonal / Q000008:administration & dosage / Q000009:adverse effects*; D005260:Female; D006801:Humans; D016015:Logistic Models; D008228:Lymphoma, Non-Hodgkin / Q000209:etiology* / Q000503:physiopathology; D016017:Odds Ratio; D034445:Ovulation Inhibition; D017584:Reproductive History; D055703:Reproductive Physiological Phenomena
D003278:Contraceptives, Oral, Hormonal