At present, cervical cancer is still one of the most common gynecological malignant tumors, which seriously threatens women's health and life, but in fact, compared with malignant tumors such as ovarian cancer, lung cancer, liver cancer, cervical cancer can be said to be a "not too cold" killer, and even a tumor that can be prevented and cured.
For cervical cancer, a "three-level prevention and control system" has been established to eliminate cervical cancer in the future, primary prevention and control refers to the vaccination of cervical cancer vaccine (referred to as HPV vaccine), secondary prevention and control refers to cervical cancer screening and treatment of precancerous lesions, and the last level of prevention and control refers to the treatment of cervical cancer in various stages.
In the context of the primary prevention and control of cervical cancer (vaccination) in mainland China, the screening of cervical cancer and the treatment of precancerous lesions in secondary prevention and control are particularly important, and even after the universalization of vaccination in the future, it cannot replace secondary prevention and control. Therefore, cervical cancer screening remains a top priority.
The importance and necessity of sampling
Cervical fluid-based cytology (TCT) is to detect whether a cell has a lesion and understand the pathological morphology of the cell, HPV testing is used to detect the presence of viral infection, and to detect the early risk of lesion progression.
At present, cervical cancer screening has been included in the mainland public health projects, widely carried out throughout the country, through improved liquid-based thin layer cytology (TCT) and HPV detection, the detection rate of cervical lesion cells can theoretically reach 100%.
However, in one clinical study[1], the matching rate of TCT and pathological biopsy results was 77.49%, while 76.2% of false-negative smears that did not contain heterogeneous cells were due to sampling errors [2].
38 percent of HPV test results in patients with cervical cancer are due to insufficient sample size [3].
Although simple and easy to perform cervical cell sampling, it is a key factor affecting the test results and will directly affect the interpretation of patient outcomes and subsequent treatment and follow-up.
Specimens satisfactory to TCT
Specimens sent for inspection are labeled with specimens and signs, with the purpose of application;
Have a clinical history to fill in the application form (age, last menstrual period, cervical description);
Have at least 5,000 or more squamous epithelial cells that are well preserved and well structured;
Adequate amounts of cervical columnar epithelial cell clumps or cell components with transitional zones
Image source: Taken by the author
Factors affecting sampling results?
1 The cell material is limited, and the deep epithelial cells cannot be obtained, resulting in low result interpretation;
2 The number of positive cells is small, resulting in abnormal cell mass has satisfied the diagnosis of mild epithelial abnormalities, but due to the small number of positive cells can only be identified as ASCUS;
3 Material extraction failure, neither to obtain diseased cells, easy to lead to high diagnostic results;
4 The specimens taken contain more blood and mucus, fewer squamous cells, overlapping cells, too thick, and poor fixation, resulting in incorrect results.
How can I optimize sampling quality?
01 Timing of sampling
1Menso terms should be avoided, with mid- and late menstruation being the most ideal.
2 Avoid placing drugs and lubricants in the vagina for 48 hours before the test.
Avoid sex, vaginal douching, and vaginal examination for 348 hours.
4 When vaginitis is severe, it should be treated first and then sampled.
5 Sampling during pregnancy should be done with caution.
02 Sampling site
Samples are taken at the junction of cervical scales or in the migration area.
03 Prepare before sampling
After adjusting the patient's position, a speculum is placed to peek open the vagina, expose the cervix, and observe the cervix with the naked eye to remove excess mucus and other secretions.
04 Operating instructions when sampling
1 The design of the broom sample sampling brush is convenient for simultaneous contact with the external cervical opening and the inside of the cervical canal, so that the center bristle of the sampling brush is inserted into the cervical canal, inserted as deeply as possible, and the surrounding bristles should fully contact the outer cervical opening.
2 Gently turn the sampling brush 5 times clockwise to avoid excessive force and reverse rotation, resulting in cervical bleeding and affecting cell collection.
3 After sampling is completed, immediately push the sampling brush to the bottom of the preservation liquid bottle, the brush is scattered, evenly shaken several times, so that the collected cells are released into the preservation solution as much as possible, and the cap is closed.
4. Indicate your name and age on the preservation bottle.
05 Precautions when sampling
Avoid menstrual sampling, and when the cervical mucus swab is difficult to wipe off during the midmenstrual sampling, it can be taken with oval forceps to avoid touching the external cervical opening.
When there is a lot of secretion, you can gently wipe it off with a cotton swab to avoid rubbing hard.
Patients bleeding after intercourse can be gently wiped off with a cotton swab before sampling.
When there is more cervical bleeding during sampling, the sampling should be stopped in time and repeated sampling should be avoided in the short term (< 3 months) to avoid false negative results.
The speculum should be kept dry and scrubbing with iodine, paraffin oil, lubricants, etc. should be prohibited.
Sampling sequence of multiple gynecological tests: naked eye observation Vaginal secretions sampling TCT Sampling HPV sampling Acetic acid/iodine solution.
Fill in the application form as completely as possible, the handwriting is neat, and the preservation liquid bottle should be sent to the laboratory in time.
How to deal with the difficulty of operation during the sampling process?
Smaller cervical openings (infertile and postmenopausal women) make cervical sampling more difficult. The cervical orifice is small, the sampling brush is more difficult to penetrate deep into the cervical opening, the number of cells taken is small, the sampling is insufficient, and it is easy to cause false negative results. Probes with probes or HPV brushes, slightly dilated cervical openings, and then TCT sampling is performed.
Caesarean section of the female cervix upwards, resulting in difficulty in exposure, you can first use double combined examination to determine the position of the cervix, and then place a speculum, expose the cervix, really difficult to expose, you can first use oval forceps to clamp the front or back lip of the cervix, downward stretching exposure and then take samples.
In patients with severe cervical erosions, rotate no more than 5 weeks to avoid excessive bleeding and dilute the cells.
bibliography:
Zhu Fenghua, et al. Compliance rate and influencing factors of cervical TCT and biopsy diagnosis[J]. Sino-Foreign Medical Sciences,2013,33(5):171-173.
Huang Yanyan, Chen Zhiheng, Zhu Xiaoling, et al. Application of liquid-based thin layer cytology in cervical cancer screening[J]. Practical Preventive Medicine,2010,17(6):1041-1043.
[3] Walboomers JMM, Jacpbs MV, Manos MM，et al. Human papillomavirus is a necessary cause of invasive cervical cancer worldwide. J.Pathol.189:12-19(1999).
Author: Teng Yuanyuan
Curator: Dongdong
This article was first published on Lilac Garden's professional platform: Maternity Time