Organ
Cervical transformation zone
The changing interface of cervical epithelial types
High-yield
This metaplastic region is a major site of HPV-associated cervical precancer. Its inner boundary is the current squamocolumnar junction.
Overview
The transformation zone records where endocervical columnar epithelium has been replaced by squamous metaplasia. It lies between the original and current squamocolumnar junctions. Its extent and visibility change with cervical growth, hormonal state and aging.
Reference facts
- Location
- May lie on the ectocervix, extend into the endocervical canal, or be largely within it, depending on age and anatomy.
- Parts
- Contains immature or mature metaplastic squamous epithelium and residual gland openings; occluded glands can form nabothian cysts.
- Blood supply
- Supplied by the cervical arterial network, chiefly uterine branches with vaginal contributions.
- Innervation
- Shares cervical innervation through the uterovaginal plexus; sensory experience cannot be inferred from epithelial type alone.
- Venous/Lymphatic drainage
- Cervical veins join uterine and vaginal plexuses; lymph reaches iliac, obturator and sacral pathways.
- Relations
- Bounded externally by the original epithelial junction and internally by the current junction with endocervical columnar epithelium.
- Function
- Represents physiological epithelial adaptation at the cervical surface; it is also a key site for assessing cervical neoplasia.
Clinical correlation
Transformation-zone visibility helps describe a colposcopic examination. Absence of transformation-zone cells in an otherwise interpretable cytology sample does not by itself make that sample unsatisfactory; interpretation also depends on the test and clinical context.
Frequently asked questions
Where is the cervical transformation zone located?
The cervical transformation zone lies may lie on the ectocervix, extend into the endocervical canal, or be largely within it, depending on age and anatomy.
What does the cervical transformation zone do?
Represents physiological epithelial adaptation at the cervical surface; it is also a key site for assessing cervical neoplasia.
What are the parts of the cervical transformation zone?
Contains immature or mature metaplastic squamous epithelium and residual gland openings; occluded glands can form nabothian cysts.
What is the blood supply of the cervical transformation zone?
The cervical transformation zone is supplied by the supplied by the cervical arterial network, chiefly uterine branches with vaginal contributions.