Colorectal Cancer Screening: A Clinical Update

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1 11:05 11:45am Colorectal Cancer Screening: A Clinical Update SPEAKER Kevin A. Ghassemi, MD Presenter Disclosure Information The following relationships exist related to this presentation: Kevin A. Ghassemi, MD: No financial relationships to disclose. Off-Label/Investigational Discussion In accordance with pmicme policy, faculty have been asked to disclose discussion of unlabeled or unapproved use(s) of drugs or devices during the course of their presentations. Learning Objectives Colorectal Cancer Screening: A Clinical Update Kevin Ghassemi, M.D. Assistant Clinical Professor Division of Digestive Diseases David Geffen School of Medicine at UCLA Discuss the appropriate surveillance recommendations based on index colonoscopic findings Evaluate the potential risks and advantages/disadvantages of various screening options Review newer screening tests and those that can be ordered by the primary care provider CRC background Statistics Cancer formation Screening options Endoscopic Radiologic Stool-based Agenda Improving CRC screening Statistics 3 rd -most common cancer 3 rd -most common cause of cancer death Incidence highest in African Americans, lowest in Asians and Hispanics Highest incidence in proximal colon Siegel et al, CA Cancer J Clin, 2014.

2 Risk factors Obesity IBD (colon involvement) Alcohol (>1 drink/day) Tobacco ( dose -response risk) Cancer formation Majority arise from adenomatous polyps Polypectomy: 75% reduction in expected CRC incidence Ma et al, PLoS One, Fedirko et al, Ann Oncol, Liang et al, Int J Cancer, Winawer et al, NEJM, The other causes Flat and depressed colorectal neoplasms Serrated polyps Screening options: endoscopic Haque et al, Curr Gastroenterol Rep, Soetikno et al, JAMA, Colonoscopy Pros The gold standard for CRC screening Full evaluation of colon Therapeutic potential (polypectomy) Detect other colorectal lesions Bowel prep Sedation Risks: abdominal pain, bleeding, perforation How golden is it? Interval cancer rate ~6% Miss rate for large adenomas (>10mm) may be as high as 12% Associated factors Suboptimal bowel prep Right colon location Incompletely removed polyp Family history of CRC Pickhardt et al, Ann Intern Med, Samadder et al, Gastroenterology, 2014.

3 Setting some standards Cecal intubation rate >95%* Adenoma detection rate 25%* 30% in men 20% in women Documentation of bowel prep quality Withdrawal time 6 minutes * Level 1 evidence Rex et al, GIE, After initial colonoscopy Baseline exam (most advanced finding) Surveillance interval (yrs) No polyps or hyperplastic polyps tubular adenomas (<10mm) tubular adenoams 3 1+ tubular adenoma 10mm 3 1+ villous adenoma 3 Adenoma w/ high-grade dysplasia 3 >10 tubular adenomas <3 Sessile serrated polyp (SSP) <10mm, no dysplasia 5 SSP 10mm or SSP w/ dysplasia 3 Piecemeal polypectomy 2-6 months Lieberman et al, Gastroenterology, Other factors Flexible sigmoidoscopy Factor Recommendation Comment CRC Colo at year 1, then 3 years later, then every 5 years 1+ 1 st degree relative w/ CRC or polyps <60 yrs 11 st degree relative w/ CRC or polyps 60 yrs or 2+ 2 nd degree relatives w/ CRC Colo starting at 40 or 10 years before the youngest case Colo starting at age 40 Subsequent colo (if normal) every 5 years Subsequent colo (if normal) in 10 years African American race Colo starting at age 45 Surveillance as per usual guidelines Levin et al, CA Cancer J Clin, Rex et al, Am J Gastroenterol, Pros Therapeutic potential Bowel prep: enemas only Unsedated Only visualizes 1/3 1/2 of the colon If polyp(s) detected colonoscopy Same risks as colonoscopy Every 5 years if negative exam How good is it? Reduced CRC incidence Reduced CRC mortality Overall and distal colon in particular No reduced proximal colon cancer mortality No difference when yearly FOBT added to screening regimen Colon capsule FDA approval (2014) for polyp screening after incomplete colonoscopy with adequate preparation Compared w/ colonoscopy 88% sensitive, 95% specific for polyps 10mm 84% sensitive, 64% specific for polyps 6 mm Schoen et al, NEJM, Holme et al, JAMA, Spada et al, GIE, 2011.

4 Issues/limitations 3 more cups of bowel prep vs. colonoscopy Contraindications Known/suspected bowel obstruction/stricture, fistula Cardiac pacemaker, other electro-medical devices Main risk: capsule retention If polyp(s) detected repeat colonoscopy Timing of next eval after negative exam??? Screening options: radiologic CT colonography (CTC) Pros Non-invasive No sedation Bowel prep still required Radiation exposure Might identify extra-colonic abnormalities Every 5 years if negative exam If polyp(s) detected colonoscopy CTC test performance Polyps 10mm Sensitivity 85-93% Specificity 97% Polyps 6mm Sensitivity 70-86% Specificity 85% Levin et al, CA Cancer J Clin, Barium enema Pros: similar to those of CTC Same limitations as CTC Lower sensitivity, specificity than CTC No possibility of same-day colonoscopy if polyp found (must re-prep to eliminate barium) Screening options: stool tests Levin et al, CA Cancer J Clin, 2008.

5 Gauiac-based testing (FOBT) Detect blood by pseudoperoxidase activity of heme, hemoglobin Reduced CRC mortality 15-33% Annual testing (if negative) Positive test colonoscopy 3 samples (higher sensitivity vs. 1) Factors that can affect accuracy Increased false (+): NSAIDs, red meat, poultry, fish, some raw vegetables Increased false (-): vitamin C Levin et al, CA Cancer J Clin, Accuracy of FOBT Wide range of sensitivity: 37-79% Specificity 85-95% Should not be performed during DRE! Sensitivity for CRC only 9% Levin et al, CA Cancer J Clin, Fecal immunochemical test (FIT) Advantages over FOBT Detects human globin (greater specificity) Not subject to false (-) results with vitamin C Human globin from UGI tract gets degraded (more specific for LGI bleeding source) Fewer samples, less direct stool handling Higher sensitivity vs. FOBT For CRC: 87% vs. 74% For advanced adenomas: 36% vs. 18% Oort et al, APT, FIT other details Annual testing Only one sample needed No diet restriction Positive test colonoscopy Oort et al, BMC Cancer, Stool DNA FDA approved (2014) to screen for CRC and advanced neoplasia CMS coverage Age Asymptomatic Average risk to develop CRC Once every 3 years Positive test colonoscopy The data behind it Quantitative molecular assays KRAS Aberrant methylation -actin Hemoglobin immunoassay Sensitivity compared with colonoscopy 92.3% for detecting CRC 42.4% for advanced pre-cancerous lesions 69.2% for high-grade dysplasia 42.4% for sessile serrated polyps 10mm Imperiale et al, NEJM, 2014.

6 Stool DNA vs. FIT Sensitivity (%) Finding Stool DNA FIT CRC Advanced pre-cancerous lesion Nonadvanced adenoma Sessile serrated polyp 10mm Improving CRC screening Specificity (%) Finding Stool DNA FIT Negative result on colonoscopy Imperiale et al, NEJM, Barriers to CRC screening Patient factors Fear of exam Poor knowledge of CRC risk Lack of perceived benefit of colonoscopy Provider factors Failure to recommend screening Knowledge deficits about guidelines, barriers to screening Systems factors Financial obstacles Lack of insurance/access to care Irregular primary care visits Bromley et al, Prev Med, Cost comparison Test Out of pocket cost ($) Medicare pt cost Colonoscopy * $0** Flexible sigmoidoscopy * $0** CTC * Not covered (initial screening) Barium enema * 20% + copayment FOBT 5 $0 FIT 22 $0 Stool DNA 599 $0 *Physician fee only, does not include facility/hospital fee **If polyp removed, then procedure considered diagnostic and patient might have to pay coinsurance A better way of looking at it Test Out of pocket cost per 10 years ($) Colonoscopy (q10 yrs) * Flexible sigmoidoscopy (q5 yrs) * CTC (q5 yrs) * Barium enema (q5 yrs) * FOBT (yearly) 50 FIT (yearly) 220 Stool DNA (q3 yrs) 1797 Improving CRC screening rates Interventions Mailing out FIT to eligible patients Post-paid return envelope Reminders by mail/phone >2x completion rate vs. giving FIT in office Lower cost per FIT returned *Physician fee only, does not include facility/hospital fee Baker et al, JAMA Intern Med, Schlichting et al, J Community Health, 2014.

7 Summary Several ways to screen for CRC Quality indicators for colonoscopy Increased polyp detection Decreased CRC rates Bottom line: when it comes to reducing CRC mortality, any screening is better than no screening