Predictors of proximal neoplasia in patients without distal adenomatous pathology.
BACKGROUND
Previous colorectal cancer screening studies have observed that some patients may have advanced proximal neoplasia without distal findings. Since these studies have included only gender, age, and family history as risk factors, they are limited in their ability to identify predictors of isolated proximal neoplasia.


METHODS
Data were collected from the charts of 1,988 patients who presented for colonoscopy. Information gathered included endoscopic findings, histology, known risk factors for colorectal neoplasia, and smoking pattern. Our main outcome was the presence of proximal adenomatous neoplasia in patients who had no distal adenomas. We defined significant neoplasia as adenocarcinoma, high-grade dysplasia, villous polyps, adenomas 1 cm or greater or more than two adenomas of any size.


RESULTS
Fifty-five patients had isolated significant proximal neoplasia that would have been missed on a flexible sigmoidoscopy. While patients older than 60 yr had a greater risk for this neoplasia (odds ratio = 3.01: 95% CI = 1.66-4.23; p < 0.001), those who took a daily aspirin had a reduced risk (OR = 0.60; 95% CI = 0.30-0.88; p < 0.05). A family history of colorectal cancer increased the patient's risk of having any adenomas (OR = 2.01; 95% CI = 1.33-3.40; p < 0.01) or villous tissue (OR = 2.03; 95% CI = 1.27-3.51; p < 0.05) in the proximal colon without distal findings. Smoking was associated with an increased risk of large (> 1 cm) isolated proximal tubular polyps (OR = 2.71; 95% CI = 1.64-4.46; p < 0.01) as well as isolated significant proximal neoplasia (OR = 2.30; 95% CI = 1.59-3.31; p < 0.01).


CONCLUSIONS
Age greater than 60 yr, a history of at least 10 pack-years of smoking, and a family history of colorectal cancer increased the risk of finding significant proximal polyps in patients without distal pathology.
Anderson
Joseph C
JC
Department of Gastroenterology and Hepatology, Stony Brook University, Stony Brook, New York 11794, USA.
Alpern
Zvi
Z
Messina
Catherine R
CR
Lane
Bernard
B
Hubbard
Patricia
P
Grimson
Roger
R
Ells
Peter F
PF
Brand
Douglas L
DL
D000236:Adenoma / Q000473:pathology*; D000368:Aged; D015179:Colorectal Neoplasms / Q000473:pathology*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D011230:Precancerous Conditions / Q000473:pathology*; D011379:Prognosis; D012307:Risk Factors