1. What is a Pap test (Pap smear) or cervicovaginal smear?
The Papanicolaou test (Pap test) is a preventive screening test that successfully detects cells indicative of cervical cancer or cells that may develop into cancer cells in the future. It was invented by the Greek physician Georgios Papanikolaou 50 years ago and has remained essentially unchanged since then.
2. Why should I have a Pap test?
Regular Pap tests help prevent cervical cancer. Cervical cells may undergo changes without symptoms or pain. Even minor abnormalities can progress to cancer if not treated. The Pap test also assesses hormonal function as well as the administration of hormonal treatments. Finally, it detects inflammations of the vagina or cervix (vaginitis, cervicitis) and their causes (bacteria, fungi, trichomonas, viruses, etc.).
3. How is the Pap test performed?
The doctor performing the Pap test gently scrapes cells from the cervix using a small spatula and a brush. The cells are spread on a glass slide, which is then sent to the laboratory for microscopic examination.
4. Is there any improvement to the traditional Pap test?
The simple spreading of the sample on a glass slide often results in uneven distribution, making accurate evaluation difficult. Additionally, studies have shown that the majority of collected cellular material does not adhere to the slide and is discarded with the spatula or brush. Today, the ThinPrep technique addresses these limitations of the conventional Pap test and represents a true improvement.
5. How does the ThinPrep Pap test differ?
Cells are collected in the same way and without any additional discomfort. But instead of being spread on a glass slide, the doctor places the cells into a vial containing a preservative solution. The spreading on the slide is then performed automatically by a specialized device. This process ensures complete collection, proper preservation, and uniform preparation of the sample. Additionally, ThinPrep allows for multiple tests to be performed on the same sample without requiring a repeat visit or collection.
6. Is there evidence that the ThinPrep Pap test is more effective?
Reliable clinical studies worldwide have demonstrated that the Pap test using the ThinPrep method provides more accurate results than the conventional smear. The ThinPrep Pap test is currently the most sensitive method for preventive screening and diagnosis of cervical abnormalities.
7. What happens if the Pap test is not normal?
If your Pap test is abnormal, it does not mean you have cancer! This often results from inflammation or infection of the cervix or vagina. When the Pap test is abnormal, your doctor will recommend the most appropriate treatment for you. Ask your doctor to explain the test and what will follow.
8. Who should have a Pap test?
All women who have had or currently have an active sexual life should undergo regular Pap tests. Even if you are not currently sexually active or no longer have periods, you should still have regular Pap tests.
9. Why should I request the ThinPrep Pap test?
The ThinPrep Pap test is the first true improvement of the Pap test since its introduction 50 years ago. This new, advanced test enhances confidence in the reliability of the examination. Take control of your health and ask your doctor for the ThinPrep Pap test today.
In summary…
Liquid-based cytology: what happens in the lab
ThinPrep is the best-known method of liquid-based cytology. Sampling in the office is similar to the conventional test. The difference lies in what happens afterward, and that explains why the result is easier to read.
- Rinsing in the vial: the doctor swirls the brush in an alcohol-based preservative fluid. The cells are fixed immediately and do not air-dry, which in a conventional smear often distorts their appearance.
- Separation: in the lab, an automated machine mixes the sample and passes it through a special filter. Much of the blood, mucus and inflammatory cells is removed.
- Thin layer: the epithelial cells are spread in a small, even circle on the slide, in an almost single layer. They do not overlap, so the cytologist sees each cell clearly.
- Staining and reading: the classic Papanicolaou stain follows. In some labs, reading is assisted by an image analysis system that flags the fields needing attention.
The remaining fluid stays in the vial. This is perhaps the method's biggest practical advantage.
What else can be tested from the same vial
Because the sample is preserved, the lab can run additional tests without you having to come back for a new sample:
- HPV test: detection of the cancer-causing types of the virus and, when requested, identification of types 16 and 18.
- Reflex HPV testing: when cytology shows a borderline finding, such as ASC-US, the HPV test is done on the same material and clarifies whether you need colposcopy.
- Molecular testing for infections: chlamydia, gonorrhea and trichomonas, using PCR techniques.
- Immunocytochemical markers: in selected cases, stains such as p16/Ki-67 dual staining help show which HPV-positive women need further investigation.
The sample remains suitable for such tests for a few weeks, according to each lab's guidelines.
ThinPrep and the HPV test in modern screening
Screening for cervical cancer is changing. In many European countries, the first test for women over about 30 is now the HPV test, and cytology is used to determine which HPV-positive women need colposcopy. In others, co-testing is done, with cytology and HPV together.
Liquid-based cytology fits all three scenarios, because one vial is enough for everything. Which screening program suits you, how often and from what age, is explained in detail in the guide to the Pap test and HPV testing.
How much more accurate is ThinPrep? What the studies show
Liquid-based cytology has real advantages, but it is worth looking at them accurately and without exaggeration.
- Fewer unsatisfactory samples: this is the most consistent finding in studies. Fewer women are asked to repeat the test because the slide could not be read.
- Easier and faster reading: the cytologist examines a smaller, cleaner area.
- Additional tests from the same sample: HPV test and infection testing without a second sample.
- Detection of precancerous lesions: large randomized trials in Europe showed that sensitivity for high-grade lesions is similar to that of a well-performed conventional smear. In other words, the benefit relates mainly to sample quality and flexibility, and less to the number of lesions detected.
In other words, proper sampling and regular screening matter more than the method. A ThinPrep every few years, at the right interval, protects far more than any technique done rarely.
How to read a liquid-based cytology report
The lab report usually follows the Bethesda system and has three parts.
Sample adequacy
It states whether the sample is “satisfactory for evaluation.” It often notes whether cells from the transformation zone are present, that is, the area of the cervix where most lesions start. Their absence in an otherwise normal report does not mean there is a problem. Your doctor will decide whether an earlier repeat is needed.
General categorization
“Negative for intraepithelial lesion or malignancy” means a normal result. Any other wording is discussed with your doctor, because most findings are mild.
Comments
This section notes findings such as yeast, a picture of bacterial vaginosis, atrophic changes after menopause or reactive changes. These are not abnormal cells. They are treated only if there are symptoms or if your doctor considers it necessary.
ThinPrep in special situations
- Pregnancy: sampling is safe in every trimester, if your scheduled screening is due. A few drops of blood may follow, which is expected.
- After menopause: atrophy makes cells harder to interpret. If the sample is unclear, your doctor may suggest local estrogen for a few weeks and a repeat test.
- After hysterectomy: if the cervix was removed for a benign reason and there was no history of precancerous lesions, screening usually stops. If there is such a history, samples are taken from the vagina at regular intervals. More about hysterectomy.
- Vaccinated women: the HPV vaccine does not cover all cancer-causing types, so screening continues as usual.
- After treatment of lesions: follow-up is done with cytology and an HPV test from the same vial, at intervals set by your doctor.
ThinPrep sampling in the office: the seconds that determine quality
The best lab technique cannot fix a poor sample. That is why those few seconds in the office matter so much.
What the doctor does
- The doctor inserts the speculum, usually with water only, so that lubricant does not affect the sample.
- The doctor uses a broom-shaped brush that is rotated a few times around the opening of the cervix, or a combination of a spatula and an endocervical brush.
- The doctor immediately rinses the brush in the vial, so no cells are lost, and closes the cap tightly.
- The doctor notes details on the request form that help the cytologist: cycle day, pregnancy, menopause, hormone therapy, previous findings.
What you can do
- Empty your bladder before the exam. It makes it easier to relax.
- Breathe slowly and let your thighs “fall” outward. Muscle tension makes sampling more uncomfortable.
- Tell the doctor if it hurts. There are smaller speculums and ways to make the exam more comfortable.
- Mention any recent symptoms of infection, so they can be tested from the same vial.
Frequently Asked Questions
What is the ThinPrep Pap test?
It is a liquid-based Pap test. The sample from the cervix is not spread on a slide but placed in a special preservative fluid and processed in the lab, so the cells can be seen more clearly.
How is it different from the conventional Pap test?
It gives fewer unsatisfactory samples, because blood and mucus are removed, and it allows an HPV DNA test or chlamydia testing to be done from the same vial, without a second sample.
Does the sampling hurt?
No. It is done like the conventional test, with a soft brush, and takes a few seconds. You may feel slight pressure.
How often should I have a Pap test?
Screening starts at 21 or when you become sexually active and is repeated at intervals set by your doctor, depending on your age and previous results. Details in our guide to Pap tests and HPV testing.
How do I prepare?
Schedule it outside your period. For 48 hours beforehand, avoid intercourse, vaginal medications, creams and douching.
What happens if the result is not normal?
Most of the time these are mild changes that are monitored. Depending on the finding, you may need an HPV test or colposcopy.
What does an “unsatisfactory sample” mean on a ThinPrep?
It means there were not enough cells or they could not be seen clearly, for example because of blood or severe inflammation. It is not an abnormal result. The sample is usually repeated after two to three months, or sooner if an infection is treated first.
Can an HPV test be done later from the same sample?
Yes. The material stays in the vial and, within the time frame set by the lab, your doctor can request an HPV test or infection testing without a new sample. This is especially useful when cytology shows a borderline finding.
Does ThinPrep also detect endometrial or ovarian cancer?
No. It is a test for the cervix. Rarely, it may detect abnormal glandular cells that lead to further testing, but it does not replace ultrasound or other tests for the endometrium and ovaries.
Do I need to fast or stop my birth control pills?
No. Sampling does not require fasting, and you don't need to stop birth control pills or other oral medications. Do tell your doctor, though, if you use vaginal products or have an IUD.
Can I have a ThinPrep if I have an IUD?
Yes. An IUD does not prevent sampling. The doctor takes care with the IUD strings so as not to pull them, and notes its presence on the request form, because it can cause reactive changes in the cells that have no clinical significance.
How long does it take to get the result?
Usually a few days to two weeks, depending on the lab and whether additional tests, such as an HPV test, were requested. If the result needs action, your doctor will contact you about the next steps.
