Risk factors for colorectal cancer in patients with multiple serrated polyps: a cross-sectional case series from genetics clinics.
BACKGROUND
Patients with multiple serrated polyps are at an increased risk for developing colorectal cancer (CRC). Recent reports have linked cigarette smoking with the subset of CRC that develops from serrated polyps. The aim of this work therefore was to investigate the association between smoking and the risk of CRC in high-risk genetics clinic patients presenting with multiple serrated polyps.


RESULTS
We identified 151 Caucasian individuals with multiple serrated polyps including at least 5 outside the rectum, and classified patients into non-smokers, current or former smokers at the time of initial diagnosis of polyposis. Cases were individuals with multiple serrated polyps who presented with CRC. Controls were individuals with multiple serrated polyps and no CRC. Multivariate logistic regression was performed to estimate associations between smoking and CRC with adjustment for age at first presentation, sex and co-existing traditional adenomas, a feature that has been consistently linked with CRC risk in patients with multiple serrated polyps. CRC was present in 56 (37%) individuals at presentation. Patients with at least one adenoma were 4 times more likely to present with CRC compared with patients without adenomas (OR = 4.09; 95%CI 1.27 to 13.14; P = 0.02). For females, the odds of CRC decreased by 90% in current smokers as compared to never smokers (OR = 0.10; 95%CI 0.02 to 0.47; P = 0.004) after adjusting for age and adenomas. For males, there was no relationship between current smoking and CRC. There was no statistical evidence of an association between former smoking and CRC for both sexes.


CONCLUSIONS
A decreased odds for CRC was identified in females with multiple serrated polyps who currently smoke, independent of age and the presence of a traditional adenoma. Investigations into the biological basis for these observations could lead to non-smoking-related therapies being developed to decrease the risk of CRC and colectomy in these patients.
Buchanan
Daniel D
DD
Familial Cancer Laboratory, QIMR, Herston, Queensland, Australia.
Sweet
Kevin
K
Drini
Musa
M
Jenkins
Mark A
MA
Win
Aung Ko
AK
English
Dallas R
DR
Walsh
Michael D
MD
Clendenning
Mark
M
McKeone
Diane M
DM
Walters
Rhiannon J
RJ
Roberts
Aedan
A
Pearson
Sally-Ann
SA
Pavluk
Erika
E
Hopper
John L
JL
Gattas
Michael R
MR
Goldblatt
Jack
J
George
Jill
J
Suthers
Graeme K
GK
Phillips
Kerry D
KD
Woodall
Sonja
S
Arnold
Julie
J
Tucker
Kathy
K
Muir
Amanda
A
Field
Michael
M
Greening
Sian
S
Gallinger
Steven
S
Perrier
Renee
R
Baron
John A
JA
Potter
John D
JD
Haile
Robert
R
Frankel
Wendy
W
de la Chapelle
Albert
A
Macrae
Finlay
F
Rosty
Christophe
C
Walker
Neal I
NI
Parry
Susan
S
Young
Joanne P
JP
D000328:Adult; D000368:Aged; D003111:Colonic Polyps / Q000150:complications* / Q000453:epidemiology*; D015179:Colorectal Neoplasms / Q000453:epidemiology* / Q000209:etiology*; D005260:Female; D006801:Humans; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D016017:Odds Ratio; D012307:Risk Factors; D012737:Sex Factors; D012907:Smoking / Q000009:adverse effects