Excision Biopsy: Definition, Procedure, Evaluation of Margins and Disadvantages

Biopsies are the most conclusive diagnostic tests for cancer.

They can be performed without surgery, as in the case of a biopsy performed with a thick needle specially designed for this purpose.

It is often done with the guidance of an image and is the standard way used to diagnose or rule out cancer.

In this procedure, only a sample of tissue is removed, which is removed without the need for surgery.

It involves the removal of a tissue nucleus from a tumor and is generally used in diagnoses of breast cancer and brain injuries.

Although the primary objective is to diagnose cancer, it can also be performed as a surgical treatment to remove the tumor. In these cases where a surgical biopsy is necessary, this can be by incision or excision.

In the first, only a portion of the tumor is removed and performed when the mass is significant; in the second, the lesion is completely removed and part of the normal tissue around it.


The excisional biopsy is performed when the mass is small enough to be eliminated.

Currently, most surgical biopsies are excisional biopsies.

The procedure

An excisional biopsy is performed by a surgeon in an operating room, with the help of a local anesthetic instead of general anesthesia, to numb the area where the tumor is located, obtaining the sample that will later be performed.

The procedure usually takes about an hour, with a minimum time of subsequent hospitalization.

Before performing the surgery, a tumor localization procedure can be achieved. A small incision will be made in the skin to access the area.

The radiologist uses a mammogram or an ultrasound image to guide a skinny wire to the suspicious area during this procedure.

This allows the surgeon and the radiologist to link suspicious areas of the mammogram with those of the biopsy tissue.

If both areas match, then the correct tissue was removed.

If the areas do not match, the surgeon can try to remove the affected tissue again or perform another new biopsy.

If performing the excisional biopsy, the surgeon can eliminate cancer, and then an excisional biopsy may be the only breast surgery needed to remove the cancerous tumor.

Then, depending on the results of the laboratory tests, a subsequent intervention may be necessary to remove the rest of the tissue and the lymph nodes.

Evaluation of margins

If the biopsy shows cancer, a pathologist will study all the tissue removed during surgery to determine if there is a sufficiently wide border of normal tissue around the tumor.

By examining the tissue samples taken from the areas adjacent to the tumor, the clinical margin.

This way, you can confirm that all diseased cells have been eliminated.

The excisional biopsy is accurate and yields few false-negative results because it is an exact technique complemented with unique examination methods, with the help of an electron microscope and antigens.

The pathology reports follow a standard scheme. A pathologist’s examination of the biopsy tissue provides information that helps plan the treatment.

When the tissues are examined, the pathologist assigns characteristics that include a grade and a stage to the tumor.

The size and dissemination of the tumor are also described to evaluate how much it has spread in the patient’s body.

These clinical aspects are the factors that can predict their behavior and indicate the most appropriate approach to treatment.

Disadvantages of excisional biopsy

The excisional biopsy is much more invasive, and its recovery time is longer and more uncomfortable.

When the excision is performed, there are more significant risks of infection, bleeding, and bruising.

The amount of tissue removed can also cause changes in the appearance and sensitivity of the breast (in the pervasive case of breast cancer or benign tumors within the breast tissue).

If the biopsy results do not show the presence of cancer, more surgery than necessary may have been performed.