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Waiting for Your Biopsy or Cytology Test Results

Waiting to hear about lab test results can be very stressful, and sometimes it can take a while to get the results back. This can be even harder when you're waiting to know if a biopsy result is cancer, or to find out if cancer has come back.

You may be going through some strong emotions, such as anxiety, fear, anger, or sadness. It's important to know that it's normal to have these types of feelings. It may help you to talk with others about it, or you may decide to keep it private.

You might be concerned about how long it’s taking to get your test results. You might be wondering if waiting for test results will affect when you can start treatment. It's important to know that each person's situation is different, and any questions you have about your test results can be answered best by your health care team.

It might also help to have a better understanding of the testing process used to diagnose and classify cancer. Knowing this, and asking your health care team questions, can help you understand what different test results might mean (including how they might affect possible treatment options), as well as why some test results might take longer than others. It can also help you know what questions to ask so you can work with your doctors to make the best decisions about your treatment.

Possible reasons for delays in getting your biopsy or cytology results

Some routine biopsy and cytology results might be ready as soon as a day or two after the sample gets to the lab. But sometimes it might take longer to get the results. There are many possible reasons for this.

It’s natural to feel concerned, stressed, or anxious while you’re waiting for biopsy or cytology test results. Not knowing when the results will be ready might cause extra concern. Knowing some of the reasons the result could be taking longer might be helpful.

Need for extra processing time

Often, there are technical reasons for delays in reporting results. For instance, some types of body tissues take longer to process than others.

Bone and other hard tissues that contain a lot of calcium need special handling. These tissues have to be treated with strong acids or other chemicals to remove the minerals so that the tissue becomes soft enough to be thinly sectioned (sliced). This takes extra time.

The formalin solution that’s used to preserve tissues takes longer to penetrate samples with lots of fatty tissue (such as breast biopsies). So, an extra day of fixation (formalin treatment) is sometimes needed. Large samples, such as when an entire organ is removed, might also require more than one day for the formalin to soak into the tissue. If formalin doesn’t penetrate the sample completely, cells might not be clearly seen under the microscope, so the microscopic exam might be more difficult and/or less accurate.

Need to look at more tissue

For most large samples, only selected areas are processed and examined under a microscope. After the first sections of tissue are seen under the microscope, the pathologist might want to look at more sections to help make an accurate diagnosis. In these cases, extra pieces of tissue might then need to be processed. Or the lab may need to make more slices of the tissue that has already been embedded in wax blocks.

Either case might add 1 or 2 days to the testing time.

Need for special stains or tests

Although most often cancers can be diagnosed by looking at routinely stained sections, sometimes special stains or other tests may be needed to ensure an accurate diagnosis. For example, if histochemical or immunohistochemical stains are needed, this usually delays results for another day. Other advanced tests like flow cytometry, electron microscopy, cytogenetics, and molecular genetic tests can take even longer before results are ready.

Sometimes a tissue specimen might need to be sent out to a specialized central lab, particularly for some types of molecular tests. Depending on the tests being done, the results of such tests might take as long as 2 to 3 weeks to come back.

Need for a second opinion

Another important reason a pathology report might be delayed is that the pathologist looking at the specimen may want to get a second opinion from an expert in a particular area.

Some tests usually give straightforward results, such as a chemical test that measures the amount of a specific substance or determines whether a substance is present or absent. But determining if there is cancer in tissue or cell samples is often based on the professional opinion of the pathologist who looks at the sample under the microscope.

Although the abnormal features of some cancers are obvious, some have features that are very hard to recognize. Pathologists are also often reluctant to diagnose certain very rare types of cancer without getting a second opinion from an expert who specializes in that area.

There are pathology experts specializing in almost every organ system (digestive, head and neck, breast, bone, reproductive, etc.). When hard or rare cases come up, slides are usually sent to experts by overnight mail or as digital images.

This review might delay the report for several days.

Other reasons

Finally, delays might occur for reasons that are neither technical nor medical. For example, entering the pathology report into the computer can take time. Many labs submit the results right into the computer system, so they are available to both the doctor and patient (through a patient portal) fairly quickly. But in some situations it might take longer for the results to become available.

The American Cancer Society medical and editorial content team

Our team is made up of doctors and oncology certified nurses with deep knowledge of cancer care as well as editors and translators with extensive experience in medical writing.

Last Revised: August 1, 2023

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