Cervix
Premalignant / preinvasive lesions - H&E
SIL variants
Author: Branko Perunovic, D.M.
Topic Completed: 1 May 2007
Minor changes: 3 December 2020
Copyright: 2007-2019 PathologyOutlines.com, Inc.
PubMed Search: SIL Variant cervix
See subtypes below: Atypical immature metaplasia Condyloma-immature HSIL with immature metaplastic differentiation HSIL with eosinophilic dysplasia
Table of Contents
Definition / general | Microscopic (histologic) description | Microscopic (histologic) images | Definition / general | Treatment | Microscopic (histologic) description | Microscopic (histologic) images | Differential diagnosis | Definition / general | Microscopic (histologic) description | Positive stains | Differential diagnosis | Additional referencesCite this page: Perunovic B. SIL variants. PathologyOutlines.com website. https://www.pathologyoutlines.com/topic/cervixSILvariant.html. Accessed January 22nd, 2021.
Atypical immature metaplasia
Definition / general
- Controversial term not accepted by most gynecologist pathologists
- Poorly reproducible diagnosis which lacks a uniform definition; spans a morphologic spectrum and includes many diagnostically challenging cases with an immature appearance
- First described by Crum et al (Cancer 1983;51:2214) as a low grade lesion but now often includes both high grade and low grade lesions
- HPV+ cases are associated with future diagnosis of HSIL
Microscopic (histologic) description
- More cellular than usual immature squamous metaplasia
- Nonpapillary, metaplastic squamous epithelium with nuclear atypic
- Basal layer of uniform cells with a uniform chromatin pattern and variable hyperchromasia
- Overlying squamous cells are monomorphic with prominent chromocenters and regular nuclear membranes
- Normal cell polarity, rare / no cell crowding
- Mitoses are < 1 per 10 HPF, normal (not atypical) and confined to lower third of epithelium
- Occasionally higher mitotic rates, multinucleation, nuclear enlargement and perinuclear halos
Microscopic (histologic) images
Images hosted on other servers:
Atypical immature metaplasia
Atypical immature metaplasia
Use of immunostains to reclassify atypical immature metaplasia:
Cytoplasmic CK17
HSIL / CINIII
Condyloma-immature
Definition / general
- Also called papillary immature metaplasia, immature exophytic LSIL, squamous papilloma
- Considered a variant of LSIL
- Infection of transformation zone epithelium that fails to mature, maintains a phenotype resembling immature metaplasia
- Involves proximal transformation zone and endocervix
- Strongly associated with HPV subtypes 6 and 11 (Mod Pathol 1992;5:391)
Treatment
- Excisional biopsy, diathermy or laser vaporization
Microscopic (histologic) description
- Patterns of immature condyloma include:
- Close similarity to squamous metaplasia with
- Mild increases in nuclear cytoplasmic ratio
- Preservation of nucleoli
- Slight nuclear crowding
- A near absence of keratinocyte maturation
- Formation of small slender filiform papillae (pathognomic)
- Frequent preservation of overlying columnar cells
- No / rare mitotic figures
- Close similarity to squamous metaplasia with
Microscopic (histologic) images
Contributed by Seema Khutti, M.D.
Slender papillae 100x
Slender papillae 200x
Slender papillae 400x
p16
HSIL with immature metaplastic dysplasia
Differential diagnosis
- Air drying artifact
- Papillary immature metaplasia: papillary not flat, less nuclear pleomorphism and atypia
HSIL with eosinophilic dysplasia
Definition / general
- Present in 10% of HSIL lesions
- Associated with HPV infection and classic HSIL in adjacent areas
- May arise from metaplastic cervical squamous epithelium that has become infected with high risk HPV
Microscopic (histologic) description
- Lack of normal maturation
- Compared to classic HSIL, cells have distinct cell borders and abundant eosinophilic cytoplasm, increased N/C ratio and focal dysplastic nuclei with nuclear enlargement, hyperchromasia, variable nuclear membrane abnormalities and distinct nucleoli
- Associated with classic SIL and squamous metaplasia
Differential diagnosis
Additional references
