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Patient handout

Colorectal cancer screening (adult)

PRODUCTION

1. Your condition

This handout is for colorectal cancer screening (adult). Your care team identified this based on: routine preventive/wellness visit — crc screening due age 45-75 (uspstf 2021 grade a 50-75 / b 45-49 pmid 34003218).

Other reasons your team may use this plan: overdue or never-screened patient identified at any encounter — health-equity recall (uspstf 2021); fdr with crc, or known lynch/fap — earlier + more frequent surveillance (nccn 2024; usmstf 2017); ibd (crohn colitis / ulcerative colitis) ≥8 yr from dx — dysplasia surveillance colonoscopy (usmstf).

2. Your medications

Take these medications exactly as prescribed. Do not stop or change a dose without talking to your provider.

MedicationStarting doseHowWhenWhat it does
colonoscopy_q10yrColonoscopy q10yr, age 45-75 average-riskprocedureq10yrAdenoma sens ~95% (reference standard). NordICC (Bretthauer NEJM 2022 PMID 36214590): ITT 10-yr CRC risk 0.98% vs 1.20% (RR 0.82, 95% CI 0.70-0.93), NNT-invite 455, CRC-death RR 0.90 (95% CI 0.64-1.16, NS at 10y — ITT dilution, 42% screened). Harm: 15 major bleeds / ~11,843 screened, no perforations/deaths ≤30d. USPSTF 2021 Grade A 50-75 / B 45-49.
fit_annualFIT annually, age 45-75labannualPooled sens 0.79 (95% CI 0.69-0.86) / spec 0.94 (0.92-0.95), LR+ 13.10, LR− 0.23 — Lee Ann Intern Med 2014 PMID 24658694; cutoff-dependent (sens 0.89 at <20 µg/g). A positive FIT raises post-test probability enough to mandate diagnostic colonoscopy.
fit_dna_stool_test_q1_3yrMultitarget stool DNA (FIT-DNA / Cologuard) q1-3yrlabq1-3yrCRC sens 92.3% vs FIT 73.8%; advanced-lesion sens 42.4% vs 23.8%; spec 86.6% vs FIT 94.9% — higher sensitivity but lower specificity = more false-positive colonoscopies (Imperiale NEJM 2014 PMID 24645800).
ct_colonography_q5yrCT colonography q5yrimagingq5yrStructural alternative; extracolonic incidentalomas are a harm; positive/incomplete CTC → diagnostic colonoscopy (USPSTF 2021).
flexible_sigmoidoscopy_q5yr_or_q10yr_plus_fitFlexible sigmoidoscopy q5yr (or q10yr + annual FIT)procedureq5-10yrUKFSS once-only (Atkin Lancet 2010 PMID 20430429): ITT CRC incidence HR 0.77 (0.70-0.84) / mortality HR 0.69 (0.59-0.82), distal CRC −50%, NNS 191 incidence / 489 death. PLCO (Schoen NEJM 2012 PMID 22612596): incidence RR 0.79 / mortality RR 0.74, distal-mortality RR 0.50, proximal mortality unaffected (distal-only test — Bayesian limitation).
lynch_aspirin_chemopreventionDaily aspirin (CAPP2 600 mg trial dose; clinical dose individualized)POdailyCAPP2 (Burn Lancet 2020 PMID 32534647): in Lynch syndrome, daily aspirin reduced CRC HR 0.65 (95% CI 0.43-0.97) ITT at 10y, incidence-rate ratio 0.58. Adjunct to intensified colonoscopy, not a substitute. No hand-authored RxCUI — screening engine; clinical dose per specialist (RxNav validation deferred per dispatch).

Plan: Colorectal — colonoscopy / FIT / FIT-DNA / CTC / flex-sig (USPSTF 2021 Grade A/B PMID 34003218; ACS 2018 PMID 29846947)

3. When to call your provider

Contact your care team if any of the following happen:

  • Advanced adenoma or CRC on colonoscopy → GI/oncology (no CRC-staging engine in repo — route narratively; USMSTF 2020)
  • Alarm hematochezia / symptomatic occult bleed → gi.lgib.core.v1 (NOT screening)
  • Confirmed Lynch/FAP → NCCN high-risk protocol + cascade testing (NCCN 2024)
  • IBD dysplasia on surveillance → gi.crohns.core.v1 / gi.ulcerative-colitis.core.v1 for management (USMSTF)

4. When to seek emergency care

Call 911 or go to the nearest emergency room right away if you have:

  • Positive FIT (LR+ ~13.10 — Lee PMID 24658694), positive FIT-DNA (CRC sens 92.3% — Imperiale PMID 24645800), positive flexible sigmoidoscopy, or incomplete/positive CTC — post-test probability now high enough that the harm of NOT working up exceeds the harm of the diagnostic colonoscopy
  • Confirmed Lynch (MLH1/MSH2/MSH6/PMS2 — CRC lifetime ~50-80%) or FAP (APC, near-100% CRC) — very high prior requiring earlier + far more frequent colonoscopy; Lynch adds aspirin chemoprevention (CAPP2 CRC HR 0.65 — PMID 32534647)
  • Hematochezia, iron-deficiency anemia, unexplained weight loss, or obstructive change in bowel habit — the patient is symptomatic; this is NOT screening (the pre-test prevalence and test characteristics no longer apply) → exit to diagnostic colonoscopy / gi.lgib.core.v1

5. Follow-up

STOP-screening logic (the deprescribing-equivalent): discontinue when life expectancy <10 yr or age >85; age 76-85 = individualized decision weighing health, prior-screening history, and patient values (USPSTF 2021 Grade C). Patient education on FIT false-positive rate, FIT-DNA lower specificity (more unnecessary colonoscopies), colonoscopy bleeding/perforation harm, non-advanced-adenoma overdiagnosis, and the value of NOT screening when harm dominates (USPSTF 2021)

6. Sources

Guideline: USPSTF 2021 colorectal cancer screening recommendation statement (Grade A 50-75 / B 45-49 / C 76-85) + ACS 2018 (start 45) + USMSTF 2020 post-polypectomy surveillance + USMSTF 2017 high-risk + NCCN 2024 Lynch/FAP

  1. pubmed.ncbi.nlm.nih.gov/34003218
  2. pubmed.ncbi.nlm.nih.gov/29846947
  3. pubmed.ncbi.nlm.nih.gov/36214590