Colitis Associated Neoplasia

Slide 1 · Colitis-Associated Neoplasia

Dysplasia, cancer risk, surveillance, and clinicopathologic decisions

Dr Abu Suraih Sakhri

MBBS, MD (Pathology)

www.abusuraihsakhri.com

Slide 2 · Learning objectives

Identify which IBD populations have increased colorectal neoplasia risk.

Explain how duration, extent, inflammation, and PSC alter surveillance.

Recognize dysplasia categories and consequential diagnostic pitfalls.

Relate lesion visibility and histologic grade to management.

Slide 3 · Colitis-associated neoplasia: The core concept

Colonic IBD

At-risk epithelium

Dysplasia

Carcinoma

Chronic colonic IBD increases the risk of dysplasia and colorectal carcinoma.

Dysplasia is a neoplastic epithelial precursor without invasive growth.

Risk is not uniform: Disease distribution and inflammatory history matter.

Slide 4 · Which IBD patients are relevant?

Colonic disease

Relevance

Ulcerative colitis

At-risk group

Crohn colitis

At-risk group

Crohn without colitis

No increased risk via colitis pathway

Slide 5 · Normal colon, inflamed colon, dysplasia

Chronic inflammation

Regeneration

Neoplastic epithelium

Possible invasion

Colonic epithelial injury and regeneration provide the tissue context.

Dysplasia describes true neoplasia—not merely active inflammation.

Invasive carcinoma is a separate diagnostic state.

Slide 6 · Ulcerative colitis: Extent is continuous

UC generally starts in the rectum and extends proximally without skip lesions.

Left-sided colitis and pancolitis differ in the amount of at-risk mucosa.

Pancolitis carries higher neoplasia risk than left-sided disease.

Simplified distribution: Extensive colon involvement

Slide 7 · Crohn colitis: Colonic involvement is decisive

Crohn disease can involve small and large bowel in discontinuous segments.

The neoplasia risk statement concerns Crohn disease with colonic involvement.

Do not extrapolate the same colon risk to isolated ileal disease.

Simplified distribution: Patchy Crohn colitis

Slide 8 · The three major risk dimensions

Longer disease duration increases cumulative exposure.

Greater colonic extent increases tissue at risk.

More frequent and severe active inflammation increases risk.

Duration

Extent

Inflammatory activity

Slide 9 · Disease duration: The late complication

A marked risk increase after approximately 8–10 years.

Duration refers to the history of IBD, not merely current symptoms.

A new episode of active symptoms does not reset the disease clock.

IBD onset

Years of colonic disease

~8–10 years: Risk rises

Slide 10 · Extent: Pancolitis versus left-sided colitis

Disease distribution

Textbook risk relationship

Pancolitis

Greater relative risk

Left-sided colitis

Lower than pancolitis

Isolated proctitis

No routine IBD-specific program if truly confined to rectum (ECCO)

Slide 11 · Active inflammation is a risk signal

The presence of neutrophils characterizes histologically active inflammation.

More frequent and more severe inflammatory episodes confer greater risk.

Distinguish activity from chronic architectural injury on biopsy.

Neutrophilic activity

Repeated mucosal injury

Higher neoplasia risk

Slide 12 · Chronicity and activity are not synonyms

Feature

Histologic implication

Architectural distortion

Chronic mucosal injury

Cryptitis / crypt abscess

Current active inflammation

Dysplastic atypia

Neoplastic transformation

Slide 13 · Inflammation burden is longitudinal

Risk assessment considers how often inflammation has recurred.

Histologic severity across examinations can be clinically informative.

A single remission biopsy cannot summarize the entire disease course.

Prior flares

Repeated activity

Cumulative burden

Current assessment

Slide 14 · Primary sclerosing cholangitis changes risk

Concurrent primary sclerosing cholangitis (PSC) identifies a higher-risk subgroup.

Surveillance beginning at diagnosis for IBD with PSC.

ECCO recommends annual surveillance following PSC diagnosis.

Requires individualized clinical action

Slide 15 · PSC: Do not apply the standard waiting period

Clinical context

Screening / surveillance start

Colonic IBD, no PSC

About 8 years after onset/diagnosis

Colonic IBD plus PSC

At PSC diagnosis

Slide 16 · A patient-specific risk synthesis

Record disease duration and historical extent.

Review endoscopic and histologic inflammation burden.

Identify PSC, prior dysplasia, stricture, and relevant family history for modern risk stratification.

Duration

Extent

Inflammation

High-risk modifiers

Slide 17 · Why surveillance targets dysplasia

Surveillance

Lesion / biopsy

Histologic dysplasia

Action

Dysplasia precedes many colitis-associated carcinomas.

Detecting a precursor may allow intervention before invasion.

Biopsies must undergo histologic assessment to establish dysplasia.

Slide 18 · The baseline surveillance timeline

Robbins: Surveillance is generally initiated about 8 years after IBD diagnosis.

ECCO: Screening colonoscopy 8 years after first symptoms to assess extent and dysplasia.

The differing anchors should not be silently treated as identical.

Symptoms / diagnosis

~8 years

Screening examination

Slide 19 · Surveillance intervals depend on risk

AGA advises repeat surveillance every 1–5 years after a negative examination.

ECCO uses shorter intervals when high-risk features are present.

The exact interval should be individualized using guideline-defined risk factors.

Lower risk

Longer reassessment interval

Intermediate risk

Intermediate interval

Higher risk

Shorter surveillance interval

Slide 20 · Examine when inflammation is controlled

Active inflammation obscures subtle lesions.

Inflammation also complicates interpretation of reactive versus dysplastic atypia.

ECCO recommends performing surveillance when IBD is in remission where feasible.

Better disease control

Clearer mucosal inspection

More reliable histology

Slide 21 · High-definition colonoscopy changes detection

Careful mucosal inspection is central to dysplasia detection.

High-definition endoscopes reveal subtle surface and vascular differences.

Histology remains necessary to classify suspected dysplasia.

Inspection → targeted tissue → histology

Slide 22 · Three endoscopic visibility categories

Category

Clinical interpretation

Polypoid

Visible projecting lesion

Nonpolypoid

Visible subtle surface lesion

Invisible

Histologic dysplasia on nontargeted biopsy

Slide 23 · Polypoid does not automatically mean sporadic

IBD patients can develop sporadic colorectal adenomas.

Polypoid IBD-associated dysplasia may resemble sporadic adenoma.

Distribution, surrounding colitis, and complete resectability matter.

Morphology alone does not establish lesion origin.

Slide 24 · Nonpolypoid dysplasia can be subtle

A minimally raised or depressed lesion may escape casual inspection.

High-quality bowel preparation and slow careful examination are important.

Suspicious mucosal irregularities warrant targeted assessment.

Subtle visible surface change

Schematic (not endoscopic or histologic evidence)

Slide 25 · Invisible dysplasia is a sampling diagnosis

The diagnosis arises on nontargeted biopsy without a documented visible lesion.

Invisible does not prove that no subtle lesion exists.

Repeat high-definition chromoendoscopy may reveal a resectable focus.

Nontargeted biopsy + dysplasia

Expert confirmation

Repeat expert examination

Slide 26 · Why apparently normal mucosa must be considered

Dysplasia may develop in macroscopically flat mucosa.

Endoscopic appearance and epithelial genotype are not equivalent.

Surveillance strategies must address lesions that are not overt masses.

Mucosal surface may look unremarkable

Schematic (not endoscopic or histologic evidence)

Slide 27 · Dye-spray chromoendoscopy

Contrast dye accentuates mucosal surface architecture.

AGA recommends considering dye-spray chromoendoscopy in colonic IBD surveillance.

Dye highlights suspicious patterns; It does not substitute for tissue diagnosis.

Contrast-enhanced surface

Abnormality recognized

Targeted examination

Slide 28 · Virtual chromoendoscopy

Method

Main principle

Dye-spray

Topical dye highlights surface relief

Virtual chromoendoscopy

Optical / digital image enhancement

Histology

Definitive dysplasia assessment

Slide 29 · Targeted versus nontargeted biopsy

Sampling

When informative

Targeted

Suspected or altered mucosa

Nontargeted

White-light surveillance or selected high-risk patients

Slide 30 · Nontargeted sampling remains situational

AGA advises extensive nontargeted biopsies when surveillance relies on white-light endoscopy without chromoendoscopy.

These are generally not routine with high-definition chromoendoscopy.

History of dysplasia or PSC can justify added nontargeted sampling.

Sampling is tailored to endoscopic technique and patient risk.

Slide 31 · Specimen mapping preserves clinical meaning

Biopsies should be attributable to a colon region or targeted lesion.

Report whether dysplasia was visible and resected versus biopsy-only.

Anatomic distribution helps assess multifocality and future management.

Simplified distribution: Patchy Crohn colitis

Slide 32 · Morphologic classification begins with H&E

Dysplasia is assessed using cytologic and architectural alterations.

Conventional dysplasia is graded as low grade or high grade.

The category “indefinite for dysplasia” addresses unresolved neoplasia versus reactive change.

Negative

Indefinite

Low grade

High grade

Slide 33 · Dysplasia is neoplasia without invasion

ECCO defines dysplasia as unequivocal epithelial neoplasia without invasive growth.

Atypia caused solely by inflammation or repair is not dysplasia.

The designation requires integration of gland architecture and cytology.

Cytologic changes

Architectural changes

No invasive growth

Slide 34 · Negative for dysplasia

Epithelium may be normal, chronically inflamed, or regenerative.

“Negative” refers to absence of established dysplasia, not absence of IBD.

Activity and architectural injury can still be reported separately.

Negative for dysplasia does not mean absence of chronic colitis.

Slide 35 · Reactive atypia can mimic neoplasia

Regeneration

Dysplasia

Inflammation / repair context

Persistent neoplastic cytology

Maturation may be preserved

Loss of normal epithelial maturation

May resolve with healing

Requires specific surveillance / therapy

Slide 36 · Indefinite for dysplasia

Use this category when a definite distinction cannot be made.

Severe active inflammation, tissue damage, and limited sampling may contribute.

A definitive low-grade diagnosis should not be forced from equivocal material.

Requires individualized clinical action

Slide 37 · Low-grade dysplasia: Nuclear abnormalities

Enlarged, elongated, hyperchromatic nuclei support dysplasia.

Pseudostratification may be evident but polarity is relatively maintained.

Interpret nuclei together with surrounding gland architecture.

Schematic: Altered epithelial nuclei and glands

Slide 38 · Low-grade dysplasia: Architectural changes

Gland crowding or altered tubular organization may be present.

Architectural abnormality is usually less marked than in high-grade lesions.

Comparison with adjacent nondysplastic mucosa aids interpretation.

Schematic: Altered epithelial nuclei and glands

Slide 39 · High-grade dysplasia: Cytologic escalation

Marked nuclear atypia and loss of polarity are concerning.

Nuclei may occupy the upper half of epithelial cells.

Prominent nucleoli and vesicular chromatin may be present.

Schematic: Marked nuclear crowding and gland complexity

Slide 40 · High-grade dysplasia: Complex glands

Back-to-back glands and cribriform configurations suggest advanced architecture.

Loss of orderly epithelial maturation accompanies severe cytologic abnormalities.

High-grade dysplasia remains noninvasive unless invasion is demonstrated.

Schematic: Marked nuclear crowding and gland complexity

Slide 41 · Low-grade versus high-grade dysplasia

Feature

Low grade

High grade

Nuclear atypia

Present, less severe

Marked / loss of polarity

Architecture

Variable crowding

Complex, cribriform possible

Invasion

Absent

Absent by definition

Slide 42 · A schematic progression of gland complexity

Normal crypts are ordered and separated by lamina propria.

Dysplastic glands become progressively crowded and irregular.

The schematic is conceptual; Real grading requires authentic H&E sections.

Ordered crypts

Crowded, atypical glands

Original conceptual schematic; Not diagnostic H&E

Slide 43 · Multifocal dysplasia changes risk interpretation

IBD-associated dysplasia may arise at more than one colonic site.

Multifocal nonpolypoid dysplasia increases concern for widespread at-risk mucosa.

Management differs from an isolated completely resectable lesion.

Simplified distribution: Distinct sites

Slide 44 · High-grade dysplasia may coexist with cancer

Carcinoma at the same site or elsewhere in the colon.

Sampling of one lesion does not exclude invasive neoplasia elsewhere.

High-grade dysplasia commonly triggers colectomy consideration.

HGD in biopsy

Concern for synchronous cancer

Multidisciplinary decision

Slide 45 · Superficial low grade may conceal deeper cancer

Invasive adenocarcinoma beneath superficially low-grade dysplasia.

Biopsy sampling may underrepresent the biologic extent of a lesion.

Discordance between endoscopic appearance and biopsy demands caution.

Superficial biopsy: Low-grade area

Deeper invasive focus may be missed

Slide 46 · The pathologist needs endoscopic context

Document lesion site, size and morphology.

State whether it was visible, completely resected, or detected only on biopsy.

Include surrounding inflammation and any previous dysplasia history.

Visibility, resection status, and prior dysplasia inform interpretation.

Slide 47 · Expert review matters

Active inflammation complicates grading and reproducibility.

AGA advocates expert confirmation of dysplasia detected on nontargeted biopsies.

Clinical and endoscopic information improves interpretive confidence.

Initial interpretation

GI pathology review

Endoscopic correlation

Slide 48 · Sporadic adenoma versus IBD dysplasia

Question

Why it matters

Is the lesion completely removable?

Supports endoscopic strategy

Is dysplasia present elsewhere?

Raises field-risk concern

What is the colitis distribution?

Provides etiologic context

Slide 49 · Use modern visibility terminology

Less useful legacy label

Preferred description

DALM / adenoma-like mass

Visible lesion: Morphology + resectability

Flat dysplasia (ambiguous)

Nonpolypoid visible or invisible

Slide 50 · The first management fork: Visible or invisible

Clearly delineated visible lesions should be assessed for resection.

Invisible dysplasia requires expert confirmation and repeat optimized examination.

Unresectability, multifocality, and grade influence surgery discussions.

Visible → assess resection

Invisible → repeat expert exam

Multifocal / HGD → surgery discussion

Slide 51 · Visible dysplasia: Assess resectability

AGA favors endoscopic resection of well-demarcated lesions without invasive features or significant submucosal fibrosis.

Questionable resectability warrants referral to an expert endoscopist or IBD center.

Histology after complete resection guides follow-up.

Visible lesion

Demarcated + resectable?

Resection / expert referral

Slide 52 · Resected solitary polypoid dysplasia

Robbins permits endoscopic removal with careful follow-up when solitary and without flat dysplasia.

Modern guidance extends assessment to any clearly demarcated resectable visible dysplasia.

A complete resection does not eliminate the need for colitis surveillance.

Successful resection must be followed by colitis surveillance.

Slide 53 · Invisible dysplasia: Repeat the examination

Confirm the diagnosis, ideally through expert GI pathologist review.

Perform high-definition dye-spray chromoendoscopy under optimal conditions.

Sample the previously implicated region if no lesion becomes visible.

Confirmed invisible dysplasia

Optimize mucosal visibility

Repeat expert chromoendoscopy

Slide 54 · When colectomy is favored

AGA recommends colectomy for unresectable visible dysplasia.

Invisible multifocal dysplasia or high-grade dysplasia favors colectomy.

Treatment decisions remain multidisciplinary and patient-specific.

Requires individualized clinical action

Slide 55 · High-grade dysplasia: The consequence

Context

Management implication

Invisible HGD

Colectomy recommended (AGA)

Unresectable visible lesion

Colectomy recommended (AGA)

Clearly resectable visible lesion

Expert endoscopic assessment

Slide 56 · Low-grade dysplasia requires context

Surveillance or colectomy depending on extent and lesion pattern.

Multifocal flat dysplasia and long-standing extensive disease raise concern.

Modern endoscopic visibility, resectability, and expert confirmation refine decisions.

Grade

Number of foci

Visibility

Resectability

Slide 57 · PSC creates a different surveillance pathway

Initiate surveillance at PSC diagnosis in patients with IBD.

ECCO recommends annual colonoscopy in this subgroup.

The intensity of current bowel symptoms does not remove this high-risk feature.

IBD + PSC

Surveillance now

Annual reassessment

Slide 58 · Risk and lesion management form one pathway

Risk profile

Inspection + biopsy

Histology

Management

First stratify colonic IBD risk and initiate surveillance.

Then detect and histologically categorize abnormalities.

Finally choose resection, intensified surveillance, or surgery according to lesion features.

Slide 59 · Case 1: Long-standing extensive UC

A patient with pancolitis of long duration enters surveillance.

Recent examinations show recurrent histologic active inflammation.

Question: Which risk dimensions are operating?

Clinical reasoning

Duration + pancolitis + inflammatory activity increase concern; Determine PSC status and past dysplasia.

Slide 60 · Case 1: The surveillance strategy

Do not assess risk from current symptoms alone.

Review inflammation history, disease extent and prior biopsy maps.

Use high-quality inspection with targeted biopsies of suspicious lesions.

Risk assessment

Optimized surveillance

Histologic classification

Slide 61 · Case 2: An invisible dysplasia report

A nontargeted biopsy is read as dysplasia, but no lesion was described.

The original examination occurred during active inflammation.

Question: What verification is needed before definitive treatment?

Clinical reasoning

Expert pathology review, inflammation control when possible, and repeat high-definition chromoendoscopy.

Slide 62 · Case 2: Grade and distribution direct action

Ask whether dysplasia is confirmed, low grade or high grade.

Determine if repeat inspection identifies a resectable lesion.

Persistent invisible multifocal or high-grade dysplasia warrants colectomy discussion.

Confirm grade

Unmask visible lesion?

Resect or discuss colectomy

Slide 63 · What is source-based, and what is updated?

Information layer

Use in this lecture

Robbins 11e (2026)

Core textbook disease concepts

AGA (2021)

Endoscopic dysplasia management

ECCO (2023–24)

Risk surveillance and histologic criteria

Slide 64 · Integrated take-home messages

Cancer risk depends on colitis duration, extent and cumulative activity.

PSC requires earlier and more intensive surveillance.

Dysplasia is diagnosed histologically and may be nonpolypoid or invisible.

Visibility, histologic grade, multifocality and resectability guide decisions.

Slide 65 · Selected references

Robbins, Cotran & Kumar. Pathologic Basis of Disease. 11th ed. 2026. Ch 17, p 733.

Murthy SK et al. AGA Clinical Practice Update. Gastroenterology. 2021.

Gordon H et al. ECCO Guidelines: IBD and Malignancies. J Crohns Colitis. 2023.

ECCO Position Paper: Definitions of Histological Abnormalities in IBD. J Crohns Colitis. 2024.

Bressenot A et al. World J Gastroenterol. 2014;20:3164–3172.