Author: PathologyMCQ Team
Category: Gastrointestinal Pathology
Last Updated: 2025
Read Time: ~18 minutes

At-a-Glance

• Nature: Benign, non-neoplastic serrated polyp
• Common site: Rectum and distal colon
• Architecture: Serrated (saw-tooth) crypts
• Crypt bases: Straight, narrow, non-dilated
• Dysplasia: Absent
• Major differential diagnosis: Sessile serrated lesion
• Treatment: Endoscopic excision

Table of Contents

• Definition
• Epidemiology
• Sites
• Etiology
• Pathophysiology
• Clinical Features
• Gross Pathology
• Microscopic Features
• Microscopic Features – Photomicrographs
• Diagnosis
• Case Correlation
• Treatment
• MCQs
• Exam Pearl
• Key Takeaways
• Recommended Learning

Definition

A hyperplastic polyp is a benign, non-neoplastic epithelial polyp characterized by superficial serrated crypt architecture without cytologic dysplasia.

• Most common colorectal polyp
• Part of the serrated lesion spectrum
• Minimal malignant potential when isolated

Epidemiology

Hyperplastic polyps most commonly occur in adults over 50 years of age.

• Frequently detected during screening colonoscopy
• Slight male predominance
• Represent the majority of distal colorectal polyps
• Rare in pediatric population

Sites

Hyperplastic polyps predominantly arise in the rectum and distal colon.

• Rectum and sigmoid colon are the most frequent sites
• Less commonly found in the proximal colon
• Gastric hyperplastic polyps are a separate clinicopathologic entity

Etiology

Hyperplastic polyps arise due to abnormal epithelial maturation and delayed epithelial cell shedding.

• Not associated with APC gene mutations
• Not true neoplastic lesions
• Often related to mucosal regenerative processes

Pathophysiology

Hyperplastic polyps result from reduced apoptosis of surface epithelial cells with preserved basal proliferation.

• Normal proliferative zone at crypt bases
• Accumulation of mature epithelial cells in superficial crypts
• Serrated architecture limited to upper crypt portions
• Crypt base orientation remains intact

Clinical Features

Most hyperplastic polyps are asymptomatic and detected incidentally.

• Occasionally associated with mild rectal bleeding
• Rarely cause pain or obstruction
• Identified during routine colorectal screening

Gross Pathology

Hyperplastic polyps are small, sessile mucosal elevations.

• Typically less than 5 mm in size
• Smooth surface
• Similar color to surrounding mucosa
• Poorly circumscribed on gross examination

Microscopic Features

Hyperplastic polyp histology shows serrated crypt architecture with preserved basal crypt morphology and absence of dysplasia.

Key Histologic Features

• Serrated or saw-tooth luminal crypt contours
• Serrations confined to the upper half of crypts
• Straight, narrow crypt bases
• Absence of crypt dilation, branching, or horizontal growth
• Mild nuclear enlargement without dysplasia

Serrated Crypt Architecture (Low Power)

Demonstrates classic serrated crypt architecture without basal distortion, characteristic of hyperplastic polyp pathology.

Superficial Crypt Serrations

Limitation of serrations to superficial crypts excludes sessile serrated lesion

Crypt Base Architecture

Straight crypt bases favor hyperplastic polyp over sessile serrated lesion and adenoma

Nuclear Features

Mild nuclear enlargement reflects physiological proliferative activity.

High-Power View

High-power view confirms benign epithelial maturation.

Diagnosis

Diagnosis of hyperplastic polyp is established by histopathologic examination.

• Based on crypt architecture and maturation pattern
• Requires exclusion of sessile serrated lesion
• Immunohistochemistry is not routinely required

Case Correlation

A typical case involves an asymptomatic adult with a small rectal polyp detected on screening colonoscopy.

• Biopsy shows superficial serrations
• Crypt bases remain straight
• Final diagnosis: hyperplastic polyp

Types of Hyperplastic polyp

Feature	Microvesicular Hyperplastic Polyp (MVHP)	Goblet Cell Rich Hyperplastic Polyp (GCRHP)
Frequency	Most common type	Less common
Architecture	Prominent serrated (saw-tooth) pattern	Mild or minimal serration
Epithelial cells	Columnar cells with microvesicular mucin	Abundant goblet cells
Goblet cells	Reduced	Increased
Cytoplasm	Finely vacuolated	Mucin-rich
Common location	Left colon > rectum	Distal colon & rectum
Molecular relevance	Associated with serrated pathway	Not a key serrated precursor

View virtual slides

Slide 1: Goblet cell rich Hyperplastic polyp

Slide 2: Microvesicular Hyperplastic polyp

Treatment

Hyperplastic polyp treatment consists of endoscopic excision alone.

• Polypectomy is curative
• No increased surveillance for isolated lesions
• Follow-up depends on associated polyps

High – yield MCQS

Exam Pearl

Superficial crypt serrations with straight crypt bases define hyperplastic polyp.

Takeaways

• Hyperplastic polyp is a benign serrated colorectal lesion
• Crypt base architecture is preserved
• Differentiation from sessile serrated lesion is essential

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