Larynx, hypopharynx & trachea
Precursor epithelial lesions
Dysplasia
Author: Nat Pernick, M.D.
Last author update: 1 November 2013
Last staff update: 30 June 2022
Copyright: 2002-2024, PathologyOutlines.com, Inc.
PubMed Search: Dysplasia larynx
Table of Contents
Definition / general | Prognostic factors | Treatment | Gross description | Microscopic (histologic) description | Additional referencesCite this page: Pernick N. Dysplasia. PathologyOutlines.com website. https://www.pathologyoutlines.com/topic/larynxdysplasia.html. Accessed December 26th, 2024.
Definition / general
- For columnar epithelium, resembles cervical dysplasia
- Associated with HPV 16 and p53 expression
- Leukoplakia: clinical term describing any white lesion on a mucous membrane; usually associated with mucosal thickening and not dysplasia
- Erythroplakia: clinical term describing red lesion on a mucous membrane; usually associated with dysplasia or malignancy; in smokers, for squamous epithelium, features of nuclear pleomorphism, mitotic activity, abnormal mitotic figures and stromal inflammation are associated with progression to invasive carcinoma
- Keratosis: increase in surface keratin, often with prominent granular cell layer and orthokeratin (cells without nuclei) mixed with parakeratin (flat keratotic cells with pyknotic nuclei); not related to dysplasia
- Dyskeratosis: abnormal keratinization of epithelial cells
- Dysplasia: spectrum of abnormal epithelial maturation and cellular atypia that may or may not precede invasive carcinoma
- Carcinoma in situ: full thickness dysplasia of mucosa without violation of basement membrane; same as severe dysplasia
Prognostic factors
- Overall, low risk of development of invasive squamous cell carcinoma after dysplasia
- For mild dysplasia, 7% develop in situ or invasive carcinoma versus 24% with moderate dysplasia versus 25% with severe dysplasia
- High risk of progression to invasive carcinoma for severe keratinizing dysplasia versus nonkeratinizing dysplasia
Treatment
- Mild / moderate dysplasia may be reversible
- Severe dysplasia requires intervention (vocal cord stripping, surgery, radiation therapy, endoscopic laser resection) as well as surveillance of entire upper aerodigestive tract
Gross description
- Erythema of involved areas
Microscopic (histologic) description
- Mild dysplasia:
- Normal or mildly disordered basal layer with retained maturation and stratification of upper layers
- Mild nuclear atypia and possibly mitotic figures in basal third of epithelium
- No abnormal mitotic figures
- Variable keratosis and chronic inflammatory infiltrate
- Moderate dysplasia:
- Moderate nuclear atypia, usually with prominent nucleoli and mitotic figures, most pronounced in lower two - thirds of epithelium
- Cell maturation and stratification are present in upper layer
- No abnormal mitotic figures
- Variable keratosis
- Severe / high grade:
- Marked nuclear abnormalities and loss of maturation greater than two - thirds of epithelium
- Large atypical nuclei, some bizarre; nuclear pleomorphism is common
- May have prominent nucleoli
- Mitotic figures high in epithelium, often abnormal
- Keratinizing dysplasia:
- Defined as lesions in which epithelial alterations are so severe that there is a high probability of progression to invasive carcinoma
- Includes dyskeratotic cells and mitotic figures with variable atypical forms above basal zone, variable surface keratinization
- Carcinoma in situ:
- Full thickness nuclear abnormalities without stromal invasion
- Cells are usually keratinized but may be basal-like
- Often lumped together with severe dysplasia
- May represent peripheral portion of invasive carcinoma
- Papillary carcinoma in situ:
- Papillary fronds with a fibrovascular core covered by squamous epithelium with marked atypia
- Note: invasion may occur by dysplastic cells without full thickness epithelial involvement
Additional references
