Top Facts About Pap Smear
Cervical cancer is characterized by the growth of cancerous cells in the lower region of uterus called cervix, which also serves as the exit route for the monthly flow of blood during menstrual cycle (or periods).
Cervix has 2 sections containing 2 different cellular types:
- Endocervix: It is the innermost section of the cervix that lines the ‘passage’ leading into the vagina, all the way from uterus. The cells present in this part are columnar and takes part in the mucus secretion.
- Ectocervix: It is the outermost section of the cervix that protrudes forward (towards the vagina). The cells present here are squamous variety and appears to be like scales of the fish.
The part where the two cell types join is usually the spot where precancerous cells of cervical cancer begins to form.
It is a type of screening test that detects the presence of cancerous and abnormal cells. The cell samples are collected from the cervix for the observation. This test can help in the early detection and prevention of cervical cancer. Human papillomavirus (HPV) and Pap smear are used for the detection of the following:
- Precancerous changes in the cell
- HPV presence
- Cancer presence
Women above 30 are recommended to undergo HPV testing as well as Pap smear test. Pap smear has played a vital role in the early detection of cervical cancer and has minimized the death rate by up to 40%. According to Mayo Clinic, women must avoid Pap smear test while being on the period. The frequency of the test is dependent on the following factors:
Women above 21 who are sexually active becomes eligible to have Pap smear done and may continue until they reach 65 years of age. Initially it’s done annually followed by once in every three years. A constant surveillance may be essential for women who have had hysterectomy for a cancerous or precancerous condition. However, after a complete hysterectomy without such conditions, the screening may no longer be a requirement.
Results Of Pap Smear
At times, there may be a false negative result due to presence of abnormal cells on the lining of the cervix. Following may be the reasons of a false negative result:
- Insufficient sample cells collection
- Inflammatory cells presence
- Blood presence
- Reduced abnormal cells quantity
A negative result shows that there was nothing wrong with the Pap smear and no that no abnormal cells were detected. A positive result may suggest the presence of abnormal cells. To further confirm the results, colposcopy may be done either alone or in combination with biopsy.
Given below are the abnormalities detected in the cells during Pap smear:
- Atypical squamous cells of undetermined significance (ASCUS), these are not usually categorized as precancerous cells.
- Intraepithelial lesions in the squamous cells; low graded lesions have less chances of progression into cancer whereas the case is vice versa for high graded lesions.
- Atypical glandular cells, it indicates the presence of abnormal cells.
- Adenocarcinoma; this is a red flag for cancer likelihood, depending on atypical cells.
- Lombardi, T. M., Kahn, B. S., Contreras, S., Waalen, J., & Levitz, D. (2016). Image Comparison of a Mobile Colposcope (EVA) versus a Standard Colposcope for Directing Cervical Biopsies in Women with Abnormal Pap Smears: A Non-Inferiority Trial. Journal of Minimally Invasive Gynecology, 23(7), S92.
- Bengtsson, E., & Malm, P. (2014). Screening for cervical cancer using automated analysis of PAP-smears. Computational and mathematical methods in medicine, 2014.