Squamous Metaplasia. The most common protective mechanism of the endocervical epithelium of the uterine cervix is squamous metaplasia. The term metaplasia implies the transformation of one cell type into another type of cell, the latter being of a lower organizational order.
Is squamous metaplasia a cancer?
Squamous metaplasia is a benign non-cancerous change (metaplasia) of surfacing lining cells (epithelium) to a squamous morphology.
What is cervical squamous metaplasia?
Squamous metaplasia in the cervix refers to the physiological replacement of the everted columnar epithelium on the ectocervix by a newly formed squamous epithelium from the subcolumnar reserve cells. The region of the cervix where squamous metaplasia occurs is referred to as the transformation zone.
Is HPV squamous metaplasia?
The importance of cervical squamous metaplasia and human papillomavirus 16 (HPV 16) infection for cervical carcinoma has been well established. Nearly 87% of the intraepithelial neoplasia of the cervix occur in the transformation zone, which is composed of squamous metaplastic cells with unclear origin.
What causes metaplasia of the cervix?
During puberty and at the first pregnancy the cervix increases in volume in response to hormonal changes. The endocervical epithelium everts onto the ectocervix (portio vaginalis) exposing it to the acid pH of the vagina. This provides a stimulus for metaplastic change of the columnar epithelium.
How is squamous metaplasia treated?
Conclusion: The therapeutic management of keratinizing squamous metaplasia is controversial, and currently no effective medical therapy is available for its treatment. Actually, patients undergo transurethral resections and a multidisciplinary approach is required to avoid cystectomy.
Is cervical metaplasia precancerous?
Process of Cervical Changes
The Pap test is taken from this area because this where dysplasia (pre-cancer) and cancer most often arise. Two common changes in cells are metaplasia and dysplasia. Metaplasia – Metaplasia is generally described as a process of cell growth or cell repair that is benign (not cancerous).
Is metaplasia benign or malignant?
When cells are faced with physiological or pathological stresses, they respond by adapting in any of several ways, one of which is metaplasia. It is a benign (i.e. non-cancerous) change that occurs as a response to change of milieu (physiological metaplasia) or chronic physical or chemical irritation.
Is squamous metaplasia reversible?
Metaplasia: the exchange of normal epithelium for another type of epithelium. Metaplasia is reversible when the stimulus for it is taken away.
What is the purpose of metaplasia?
Improved clinical screening for and surveillance of metaplasia might lead to better prevention or early detection of dysplasia and cancer. Metaplasia is the replacement of one differentiated cell type with another mature differentiated cell type that is not normally present in a specific tissue1.
Should I worry about squamous metaplasia?
There is no risk of malignant transformation for squamous metaplasia. Nevertheless, the metaplastic change within the endocervix may increase the risk for human papilloma virus infection (Hwang et al., 2012), which is a risk factor for cervical cancer.
Does HPV cause cervical metaplasia?
Active Squamous Metaplasia of the Cervical Epithelium Is Associated With Subsequent Acquisition of Human Papillomavirus 16 Infection Among Healthy Young Women.
What is a metaplasia?
Listen to pronunciation. (meh-tuh-PLAY-zhuh) A change of cells to a form that does not normally occur in the tissue in which it is found.
Is metaplasia normal?
Metaplasia can also occur as a normal physiologic response. An example of physiologic metaplasia is the squamous metaplasia that occurs in the uterine cervix during the menstrual cycle as the squamocolumnar junction migrates across the transformation zone (Fig. 1-13).
What are the treatments for precancerous cervical cells?
A precancerous lesion affecting these cells is called AIS. Treatments for precancerous lesions include excision (surgical removal of the abnormal area, also referred to as a cone biopsy or conization, or loop electrosurgical excision procedure [LEEP]), cryosurgery (freezing), and laser (high-energy light).
What is atypical squamous metaplasia?
The term atypical immature squamous metaplasia (AIM) was initially introduced in 1983 to describe lesions in the uterine cervix featuring a uniform intraepithelial full-thickness basal cell proliferation with high nuclear density in the absence of maturation but without sufficient criteria for a diagnosis of high-grade …