Evaluating the Burden and Predictors of Colorectal Neoplastic Lesions in Young Patients Undergoing Diagnostic Colonoscopy

Introduction: Incidence of young onset colorectal cancer (YOCRC) in patients < 50 years is increasing. Although current guidelines recommend starting screening at age 45, there is limited data on prevalence and characteristics of colrectal neoplastic lesions (CNL) in patients < 50 years. We set out to determine the overall prevalence, characteristics of CNL in patients < 50 years. Given the increasing trend in obesity, diabetes mellitus type II (DMII) and smoking, we also aimed to explore if there was a correlation between CNLs and above and other risk factors. Methods: All patients < 50 years who underwent colonoscopy for any indication between Jan 2012 and Dec 2018 were included. Data on demographics, risk factors, indications, number and polyp pathology was collected. Patients with inadequate preparation, personal history of (h/o) colon polyps or colon cancer, inflammatory bowel disease were excluded. Logistic regression was performed to determine predictors of adenoma detection. Results: Of 5749 patients who had colonoscopy, 4156 were eligible. Mean age was 38.8 years (SD 8.42). Demographics, risk factors, indications for the procedure are shown in Table 1. Abdominal pain (38%), family h/o CRC (38%), diarrhea (34.9%) were the most common indications. Information on polyp characteristics based on age groups is shown in Figure 1. Polyp detection rate was 32.2% (n = 1337). Of those with polyps, 647 (48.4%) had adenomas. Majority of the adenomas were tubular adenomas (45.3%); tubulovillous adenomas were less common (3.1%). Adenoma detection rate was 15.6%. Sessile serrated lesions (SSL) accounted for 17.4%. Detection rate for SSL (SSLDR) was 5.6%; when stratified by age groups, the DRSSL increased from 3.7% in the < 39 year cohort to 7.3% in 40-49 years cohort, however, this was not statistically significant. On multivariate analysis, family h/o colon cancer (1.28) and BMI (1.05) were associated with higher odds of adenoma detection. Interestingly, there was no significant correlation of polyps with DMII and smoking. Conclusion: There was an increasing trend in the prevalence of adenomatous polyps and advanced adenomas with increasing age. DRSSL was similar in the 40-44 and 45-49 age groups, but doubled when compared to < 39 year-olds, although not statistically significant. Large population based studies are needed to confirm this observation. BMI and family h/o colon cancer were independent predictors of adenoma detection in our cohort. Table 1. - Demographic and Clinical Characteristics of the Entire Cohort Stratified by Presence or Absence of Polyps Demographics No Polyps (n = 2819) Polyps (n = 1337) Total (n = 4156) P value Female, n (%) 1828 (64.8) 692 (51.8) 2520 (60.6) < 0.0001 White, n (%) 2341 (63.6) 1125 (84.3) 3466 (83.8) 0.4372 Clinical Characteristics, Comorbidities and Risk Factors Mean BMI (+/- SD) 26.7 (6.46) 30.9 (8.14) 28.1 (7.31) < 0.0001 Diabetes, n (%) 144 (5.1) 100 (7.5) 244 (5.9) 0.0031 Hypertension, n (%) 368 (13.1) 263 (19.7) 631 (15.2) < 0.0001 Tobacco use, n (%) 617 (21.9) 437 (32.7) 1054 (25.4) < 0.0001 NSAIDs use, n (%) 542 (19.2) 300 (22.4) 842 (20.3) 0.0420 Statin Use, n (%) 151 (5.4) 104 (7.8) 255 (6.1) 0.0056 Indications for Colonoscopy F/H Colon Cancer, n (%) 418 (14.9) 355 (26.6) 773 (18.6) < 0.001 F/H Colon Polyps, n (%) 145 (5.1) 156 (11.7) 301 (7.2) < 0.0001 Abdominal pain, n (%) 1005 (35.7) 440 (32.9) 1445 (34.8) 0.0241 Anemia, n (%) 181 (6.4) 117 (8.8) 298 (7.2) 0.0065 Weight loss, n (%) 152 (5.4) 73 (5.5) 225 (5.4) 0.8594 Rectal Bleeding, n (%) 671 (23.8) 347 (26) 1018 (24.5) 0.1320 Constipation, n (%) 417 (14.8) 254 (19.0) 671 (16.2) 0.0028 Diarrhea, n (%) 1061 (37.6) 389 (28.3) 1450 (34.9) < 0.0001 Abnormal Imaging, n (%) 65 (2.3) 19 (1.4) 84 (2.0) 0.0583 Other, n (%) 557 (19.8) 391 (29.2) 948 (22.8) < 0.0001 Figure 1.: Polyp characteristics and detection rates.