Histopathology Interpretation Report

Anatomic Pathology — Whole-Slide Imaging Review of Colonic Polyp

Report ID: MAA-HST-4D7C39
Generated: June 5, 2026
Analysis: AI-Powered Image Interpretation

Specimen Profile

Sex / Age:
Male, 59 years
Specimen:
Colonoscopic polypectomy, sigmoid colon, 12 mm pedunculated polyp
Indication:
Average-risk colorectal cancer screening colonoscopy
Other findings at endoscopy:
Two small (3–4 mm) hyperplastic polyps in the rectum (resected separately, reported in linked report)
History:
No personal or family history of colorectal cancer or IBD; no prior surveillance findings
Slide review:
Whole-slide H&E digital imaging, multiple levels

Summary Overview

The 12 mm sigmoid pedunculated polyp shows histologic features of a tubular adenoma with low-grade dysplasia. Margins are free of dysplastic epithelium. No high-grade dysplasia, no invasive carcinoma, no lymphovascular invasion identified.

Tubular
Architecture
Low-Grade
Dysplasia
R0
Margins Clear

Polyp Classification (WHO 5th Ed. 2019)

Conventional adenoma — tubular:
≥ 75% tubular architecture
Tubulovillous adenoma:
25–75% villous
Villous adenoma:
≥ 75% villous
Sessile serrated lesion (with/without dysplasia):
Distinct entity with crypt architectural distortion
Reference:
WHO Classification of Tumours of the Digestive System, 5th Ed. 2019

Microscopic Findings

ArchitectureTubular Adenoma
Predominantly tubular glandular architecture (> 90% tubular). No significant villous component. Stalk demonstrates non-neoplastic colonic mucosa.
Cytology / DysplasiaLow-Grade
Pseudostratified, hyperchromatic, elongated nuclei oriented along the basement membrane (basal polarity preserved). Nuclear-to-cytoplasmic ratio mildly increased. Mitoses occasional, located at the basal half of the crypts. Goblet cell depletion is partial. No high-grade features: no architectural complexity (no cribriforming), no loss of polarity, no markedly atypical nuclei [Schlemper RJ, Gut 2000; Riddell RH, Hum Pathol 1983].
InvasionAbsent
No invasion through the muscularis mucosae. No tumor cells in stalk vessels. No infiltrative pattern. Specifically: no submucosal invasion, no lymphatic or vascular invasion, no perineural involvement.
MarginsClear
Stalk margin examined and is free of dysplastic epithelium. Margin-to-dysplasia distance > 2 mm in all examined sections. No fragmentation that would prevent margin assessment.
Background MucosaNo IBD
Adjacent non-polypoid mucosa shows preserved crypt architecture without inflammation or features of inflammatory bowel disease. No serrated change.

Diagnosis & Risk Stratification

  • Tubular adenoma with low-grade dysplasiaConfirmed
    Classic morphology with preserved basal nuclear polarity, no architectural atypia, no high-grade features. WHO 2019 conventional adenoma — tubular type.
  • High-grade dysplasiaExcluded
    Absence of cribriform architecture, marked nuclear atypia, or loss of polarity rules out high-grade dysplasia.
  • Invasive adenocarcinomaExcluded
    No invasion of muscularis mucosae or submucosa. Margins free.

Analytical Summary & Recommendations

Pathologic impression

Sigmoid colon, polypectomy: Tubular adenoma with low-grade dysplasia, 12 mm. Margins free of dysplasia. No high-grade dysplasia or invasive carcinoma.

Recommended surveillance (US Multi-Society Task Force, 2020)

  • Repeat colonoscopy in 7–10 years — appropriate for 1–2 small (< 10 mm) tubular adenomas, but this 12 mm adenoma falls into a slightly higher-risk category
  • Patient profile: 1 adenoma 10–19 mm with low-grade dysplasia → recommended 3-year surveillance interval [Gupta S, Gastroenterology 2020]
  • The 2 small hyperplastic polyps in the rectum do not modify the surveillance interval
  • Continue routine age-appropriate colorectal cancer screening guidance with the gastroenterology team
  • Lifestyle: maintain dietary fiber, limit processed/red meats, avoid smoking, moderate alcohol — all reduce future adenoma risk

Key Questions for Your Physician

  • Given the size of the adenoma, when is my next colonoscopy recommended?
  • Did the pathologist see anything that requires further evaluation (e.g., MMR/MSI testing)?
  • What lifestyle steps reduce my risk of more polyps?
  • How does my family history affect the surveillance plan, if at all?
  • Are there symptoms that should prompt earlier follow-up (bleeding, change in bowel habits)?

What This Means for You

The polyp removed during your colonoscopy is a tubular adenoma with low-grade dysplasia. In plain terms: this is a benign growth of cells that, over many years, can sometimes progress toward cancer if left in place. Removing it during the colonoscopy is exactly how we prevent colon cancer from developing.

The good news: the entire polyp was removed, the edges (margins) are clear, and there is no high-grade dysplasia and no invasive cancer. The 2 small polyps in the rectum were "hyperplastic" — these are very common and do not have a meaningful risk of progression.

Because the adenoma was on the larger side (12 mm), the recommended next colonoscopy is in 3 years, rather than the standard 7–10 years used for very small adenomas. This is to make sure no new growths develop and to remove any if they do.

In the meantime: a fiber-rich diet, limited processed/red meat, no smoking, and moderate alcohol intake are all helpful. Report any rectal bleeding, persistent change in bowel habits, or unintended weight loss to your physician immediately.

Analysis Confidence 94%

High confidence in architectural classification, dysplasia grading, and margin assessment given complete sectioning and standard H&E review. Final sign-out attribution rests with the reporting pathologist.

References

  1. WHO Classification of Tumours Editorial Board. WHO Classification of Tumours: Digestive System Tumours. 5th ed. IARC 2019.
  2. Gupta S, Lieberman D, Anderson JC, et al. Recommendations for Follow-Up After Colonoscopy and Polypectomy: A Consensus Update by the US Multi-Society Task Force on Colorectal Cancer. Gastroenterology 2020;158(4):1131–1153.
  3. Schlemper RJ, Riddell RH, Kato Y, et al. The Vienna classification of gastrointestinal epithelial neoplasia. Gut 2000;47(2):251–5.
  4. Riddell RH, Goldman H, Ransohoff DF, et al. Dysplasia in inflammatory bowel disease: standardized classification with provisional clinical applications. Hum Pathol 1983;14(11):931–68.
  5. USPSTF. Colorectal Cancer: Screening — final recommendation. JAMA 2021;325(19):1965–1977.