Pap smear is a screening examination performed by evaluating cells taken from the cervix by scraping with a spatula and/or brush on the basis of single cell appearance. The cells are thinly smeared on a microscope slide and quickly fixed to the glass with chemicals to prevent the cells from spoiling. In recent years, liquid-based analysis has come to the fore, and according to this method, cells are suspended in fixative solution, dispersed, and then cells are specially collected in a filter. The cells are then transferred to the microscope glass for cellular evaluation.
TO WHOM IS PAP SMEAR APPLIED?
It recommends that every woman have a Pap smear test from the age of 21 or 3 years after the start of sexual activity, whichever comes first. Most organizations recommend extending the Pap smear interval to 3 years after 2 or 3 cellular normal annual smears. It recommends annual screening for those who have a history of pre-cancer disease in the cervix, which we define as a high-risk group, human papillomavirus or other sexually transmitted infections, and those who have a relationship with people with high-risk sexual behavior.
New recommendations from the American Cancer Society (ACS) support discontinuation of screening at age 70 if there are 3 consecutive normal or negative tests in unassisted women who have not had an abnormal or positive test result in the past 10 years. It is appropriate to discontinue Pap smear screening after hysterectomy for non-cancerous diseases.
PRE-CANCER CERVICAL LESIONS
Cervical dysplasia are precancerous changes in the cervical tissue that can progress to the development of cervical cancer. CIN I (Cervical Intraepithelial Neoplasia) corresponds to dysplasia limited to the lower 1/3 tissue part. CIN II is cellular dysplasia limited to the lower 2/3. CIN III is a disease that affects more than 2/3 of the thickness of the cervical tissue.
Cell abnormalities that can be seen on Pap smear
Squamous Cell Abnormalities
Atypical squamous cells (ASCs) atypical squamous cells of undetermined significance (ASC-US).
Atypical squamous cells (ASC-H) where HSIL (high-grade lesions) cannot be excluded.
Includes low-grade squamous intraepithelial lesion (LSIL), human papilloma virus, mild dysplasia, and cervical intraepithelial neoplasia (CIN) 1
High-grade intraepithelial lesion (HSIL) includes moderate to severe dysplasia, CIN II and CIN III. Squamous cell carcinoma in situ includes CIN II and CIN III.
Glandular Cell Abnormalities
Atypical glandular cells (AGCs): Defined as the lining of the cervix or inner wall of the uterus, or not otherwise identified.
Atypical glandular cells favor cancer.
Defined as inner part of the cervix or not otherwise specified (AGC-NOS).
Adenocarcinoma in situ (AIS) of the inner part of the cervix; cancer.
WHERE ARE CERVICAL DYSPLASIAS USUALLY LOCATED?
Approximately 95% of squamous intraepithelial neoplasias develop from a special region in the cervix known as the “transformation zone”. The cervical transformation zone is where the glandular cell structure begins to replace the flat cell structure in the outer part of the cervix.
WHAT ARE THE RISK FACTORS FOR CERVICAL DYSPLASIA?
Human papilloma virus (HPV) infection (oncogenic types 16,18, 31, 33, 35, 39, 45, 51, 52, 56, 58, 59 and 68)
Sexual activity at an early age
History of sexually transmitted disease
Relationship with multiple sexual partners or people with risky sexual behavior
Cigarette
having multiple births
Suppressed immunity (HIV, transplant patients)
Despite all this, HPV is the most important risk factor for cervical dysplasia.
HOW DOES HUMAN PAPILLOMA VIRUS INFECTION DIRECTLY CAUSE CERVICAL DYSPLASIA?
HPV causes cellular changes. These cellular changes are found in genital warts and often in the area of intraepithelial neoplasia. Combination of HPV with oncogenic proteins and loss of tumor suppressor genes and consequent cancer cell growth is the possible mechanism.
When is HPV DNA testing done?
This test is done in the following cases:
If the Pap smear result is ASC-US
Pap smear result 12 months later for follow-up of colposcopies for ASC-H and LSIL
What is colposcopy?
Colposcopy is the visual examination of the cervix for cellular changes under magnification with a special microscope and with the application of acetic acid. The pathological diagnosis is determined by taking biopsies from abnormal areas visible on colposcopy.
Are there any special screening approaches for pregnant women?
Pregnant women should have a Pap smear at their first visit.
The content of the page is for informational purposes only, please consult your doctor for diagnosis and treatment.
Content Update Date: 26.12.2022