Cytopathology reports can be used to help diagnose mesothelioma. By looking at fluid samples under a microscope, doctors can find clues leading to a diagnosis.

Detecting Mesothelioma in Fluid Samples

Cytology reports are used to test fluid samples for mesothelioma cells. These tests are less invasive than procedures requiring tissue biopsies and can provide more evidence for a diagnosis. Getting the best diagnosis possible is essential to improving your survival rate.

Importance of Cytology

  • Diagnosis

    Imaging tests such as x-rays and CT scans have limitations when it comes to diagnosing mesothelioma. Cytology tests can further explain suspicious imaging tests and in some cases can be used to determine the patient’s cell type.

  • Less invasive

    Cytology reports only require a simple extraction of fluid buildup in the chest or abdomen in suspected mesothelioma patients. Patients can remain awake for the relatively quick procedure.

  • First line of testing

    If a doctor suspects a patient may have mesothelioma, they may order a cytology test before committing to a tissue biopsy. These tests aren’t as accurate as tissue biopsies but can provide important clues about the diagnosis.

What is Cytology?

Cytology is the study of cell structure and function. Mesothelioma cytology evaluates the behavior of mesothelioma cells. This process is useful for doctors in diagnosing, researching, and understanding mesothelioma.

Mesothelioma cytology is referred to as “cytopathology” because it encompasses the field of pathology—the study of the behavior of diseases. Cytopathology is the branch of pathology that studies diseases via fluid samples.

Doctors must take a fluid biopsy from a patient to conduct a cytology report. Fluid samples are collected from patients when they begin experiencing symptoms of mesothelioma. Fluid biopsies are far less invasive than tissue biopsies, and the patient remains awake during the procedure.

Depending on the suspected type of mesothelioma, fluid samples are collected from:

  • Pleural effusions – fluid surrounding the lungs
  • Ascites – fluid surrounding the abdomen
  • Pericardial effusions – fluid surrounding the heart

How Fluid Samples Are Collected

Fluid samples are collected through fine needle aspiration. Doctors don’t make any incisions during the procedure. Throughout fine needle aspiration, doctors use a syringe with a thin needle to remove fluid from a suspected tumor area. Meanwhile, patients can stay awake for the whole process with the aid of numbing medicine placed on their skin.

How Do Doctors Test Fluid Samples?

MicroFluidSamplePreparing fluid samples can vary depending on the number of cells and amount of blood that is collected in the sample.

Samples with a lower cell count may require a doctor to use a high-powered microscope to examine them. Blood-stained samples will require special solutions to dilute the blood.

Fluid samples are put on slides and dipped into a collection of stains or chemical dyes. These stains start working in approximately one minute.

The three most commonly used stains are:

  • Diff Quick
  • Papanicolaou
  • May-Grünewald-Giemsa

Each stain is attracted to certain elements of the cancer cell and causes a reaction that changes the cell’s color. When pathologists observe this under the microscope, they are able to assess whether the fluid sample contains, or does not contain, mesothelioma cells.

By looking at the size and shape of cells, pathologists are able to compare samples to the likeness of mesothelioma cell types or other diseases. Research suggests that cytology is most useful in diagnosing epithelioid mesothelioma. This cell type makes up 70 percent of all mesothelioma cases. Epithelioid is known for being easy to distinguish due to its elongated egg-shape and defined nucleus.

Although cytology reports can be useful to determine a diagnosis, they cannot definitively diagnose mesothelioma. This is because sometimes it is hard to differentiate between reactive mesothelial cells and mesothelioma.

Learn more about how mesothelioma is diagnosed in our free Mesothelioma Guide.

Cytology vs. Histology

The primary difference between cytology and histology can be described based on the type of biopsy that occurs.

Cytology reports are less conclusive than a histology report. They are also less invasive because they don’t require a tissue biopsy.

One study reported accurate diagnoses of 98 percent of patients with histology, 26 percent with cytology tests and 21 percent with fine needle aspiration.

There are, however, several benefits of cytology reports over histology reports, and doctors may prefer to take a fluid sample before an invasive tissue biopsy. Most of the benefits of cytology lab tests have to deal with the nature of the biopsies.

Some benefits of cytology tests include:

  • Fluid samples are easier to retrieve
  • Virtually no risk of complications
  • Less costly than tissue biopsies
  • Less discomfort for the patient
  • Faster procedure than tissue biopsies

A patient that experiences fine needle aspiration doesn’t have to undergo anesthesia. They will also be pleased to learn that unlike a tissue biopsy, this procedure will not leave them with a scar.

Limitations of Cytology and Needle Biopsies

The overreaching limitation of cytology reports is the lack of accuracy in diagnosing mesothelioma. There are two predominant reasons cytology has limitations.

Not all cases of mesothelioma have enough fluid buildup to obtain a significant sample. Doctors cannot diagnose the extent of metastasis because of this. If the fluid sample doesn’t have enough cells, it may not be possible to determine if the sample is mesothelioma or a disease with similar traits, such as adenocarcinoma.

Cytology is also limited by the process of fine needle aspiration. It can be difficult to accurately aim the needle toward the area of suspected tumor growth. Typically the needle is guided by a CT scan because mesothelioma tumors may be too deep in the chest or abdomen.

Doctor Experience Counts in Cytology

The experience and abilities of a doctor performing fine needle aspiration can play a large part in the accuracy of a cytology report. When performing the aspiration technique experts cannot agree on the best approach.

Some specialists may use a syringe holder (gun), whereas some experts believe it isn’t necessary. It is thought that using a gun helps provide more control by the user and more cells for examination.

Having cytology tests performed by an experienced doctor is vital to a mesothelioma patient.

Approximately 10–15% of patients receive an insufficient diagnosis.

Get connected with a specialist experienced in mesothelioma cytology using our free Doctor Match program.