Aziza Nassar, MD, FCAP, is Professor of Pathology and Director of Cytopathology at the Mayo Clinic in Jacksonville, FL.
There is a member of your health care team who plays a vital role in your diagnosis and cancer care who you may never meet face to face: the pathologist. This is the doctor who analyzes the sample of tissue removed during a biopsy to make the correct diagnosis.
1. Biopsy sample size and location matter.
Pathologists are trained to evaluate many different types of tissue. They use powerful microscopes to evaluate the cells within each tissue sample.
Sometimes a biopsy sample might not be big enough to evaluate. Other times, the pathologist can see that the sample was not taken from the correct area. In these cases, the pathologist will ask your doctor to repeat the biopsy, so the pathologist can make a conclusive and accurate diagnosis.
2. The time required for biopsy results will vary.
Some biopsies can be performed in a doctor’s office or an outpatient clinic. These include shave biopsies, punch biopsies, Pap tests and cervical biopsies, and even some fine needle aspiration biopsies (FNABs) for the thyroid or lymph nodes. These procedures are usually fairly quick and might take 15 to 30 minutes to perform, depending on the part of the body being biopsied.
Typically, the biopsy sample is then saved in a special type of preservative and sent to the pathology lab for processing. Tissue processing takes several steps, but it starts with making sure the correct test was done on the correct patient. Depending on the type of evaluation needed, the next steps might take a few hours or several days.
If your pathologist suspects certain types of cancer, such as lymphoma, he or she might need to perform additional testing to determine the subtype. This process takes an additional 24 to 96 hours, depending on the complexity of the cancer.
It can be agonizing to wait for biopsy results. But be assured that the pathologist is using his or her specialized expertise to make sure you get an accurate diagnosis.
3. Pathologists make sure biopsy tissue is used effectively to determine an accurate diagnosis.
Pathologists are the caretakers of tissue samples and must exercise good judgment with them. Samples allow us to make a correct diagnosis. But we can also use the samples to perform additional tests, such as immunostains, which can identify where a tumor started. This is really valuable in treating cancer that has spread from another part of the body, called metastasis.
Your pathologist will also make sure that biopsy samples are used to identify other factors affecting your treatment and recovery. These can include genetic changes that could guide treatment options or predict your chance of recovery. For example, in breast cancer, pathologists use the biopsy sample to identify hormone receptors such as estrogen and progesterone receptors (ER and PR) and human epidermal growth factor receptor (HER2). As we identify more precise characteristics of cancer from the biopsy sample, we can identify a growing number of patients who may benefit from new, more effective targeted therapies.
4. Biopsy samples are safely stored and secured to help manage future treatment.
Federal law requires laboratories to safely store specimens for a set amount of time. For example, cytology slides, like Pap tests, are usually stored for at least 5 years. Other types of stained tissue slides are typically kept for 10 years or more. Paraffin blocks (material where tissues are usually processed) are retained for at least 10 years. Some states may require even longer storage periods.
By saving biopsy tissue for a long time, the pathologist may review the primary tumor if a patient has that cancer come back or spread in the future. By looking at the sample again, we can find out if the original primary tumor has come back or if it is a new cancer. We also may review the samples again if new treatments based on a tumor’s genetics become available. At other times and only if the patient gives permission, biopsy samples may be used in research to help discover new treatments and targeted therapies.
5. Pathologists seek multiple opinions, and patients can, too.
Typically, pathologists share all cancer diagnoses with their associates, especially when a patient has a cancer that is difficult to diagnose or treat. Most accredited labs require a second pathologist to confirm the diagnosis for all cancers.
In addition, pathologists participate in tumor board review. Tumor board review is an approach to planning cancer treatment in which a team of doctors from different specialties work together to reach an opinion.
This multilayered team evaluation helps ensure that patients receive a detailed and accurate diagnosis. And because we understand the value of gaining a second opinion, all laboratories are willing to give patients their biopsy samples if they want a second opinion or treatment from another cancer center.