Biopsy

Cervical cancer is staged clinically. This means that if the tumor is very early and only detected by a biopsy, then a cold-knife cone is performed to determine the depth of tumor invasion and thus the stage. If the patient has a visible lesion, then the tumor is staged based on a pelvic examination. During that examination, the physician is trying to assess tumor size and extent within the pelvis. A chest x-ray is commonly obtained to assure that there is no evidence of spread of disease. Surgery is not routinely used to stage cervical cancer.

The chance of the sentinel node(s) having melanoma that has spread from the skin varies by the thickness of the primary melanoma (and other factors such as ulceration, mitotic rate, vertical growth phase). For melanomas <1 mm, it is ~5-7%; for 1-4 mm, it is 12-24%; and >4mm, it is ~25-40%. However the vast majority of time the sentinel node only has a microscopic deposit of melanoma so it is unusual to discover this at the time of sentinel lymph node biopsy. Therefore, I never (rarely) do a complete dissection at the time of sentinel lymph node biopsy, waiting instead for the final pathology report. If there is a 'positive' sentinel lymph node, then the standard of care is to remove the rest of the lymph nodes in that basin (neck, axilla, groin). These basins are defined by anatomic landmarks (not absolute number of nodes) and all tissue within those boundaries is removed. The number of lymph nodes removed will vary by patient with some patients having just a few and some patients having a lot (like most things in medicine the number of lymph nodes in a basin is a bell shaped curve). There is a large international study going on (Multicenter Selective Lymphadenectomy Trial- II) that is trying to determine if we need to do a complete dissection for those patients with a positive sentinel node. The study is a randomized (meaning a computerized coin toss) trial comparing the standard of care (complete lymphatic dissection) vs no further lymphatic surgery (with ultrasound examination of the lymph node basin every 3 months to look for metastatic lymph nodes). The patient can choose to be in the study but cannot 'pick' their therapy (surgery vs observation of their lymph nodes). If you want further information on this trial please email me at beitsch@aol.com

Image-guided biopsy is preferred. This can be done with a core biopsy using the stereotactic table or under ultrasound. There are many different biopsy needles available, but for all a small knick is made in the skin after injecting local. The devise is then inserted into the breast, and several cylinders of tissue are removed and placed in formalin then sent to pathology.

Time enough to absorb the volumes of information provided, discuss issues with family, obtain second opinions if desired, and consult with other specialists such as radiation oncologists and plastic surgeons. Usually this will be two to three weeks. An MRI may be ordered as well, in the time between diagnosis and surgery. I usually allow a week between MRI and a surgery date to act on the results if need be. There is no set time limit. Some patients want surgery as soon as possible; others wish to research more themselves.

Pre-melanoma (http://www.cancercenter.com/melanoma/melanoma-information.cfm), also often referred to as “atypical nevus,” or “dysplastic nevus,” refers to moles (nevi) that do not have uniform pigmentation or shape or borders, but which, at the same time, have not yet progressed into actual melanoma when viewed under the microscope. While there is no standard clinical definition of pre-melanoma, dermatologists and surgeons often informally refer to these types of pigmented skin lesions as “FLMs,” or “funny looking moles.” We know that these atypical moles are at increased risk of progressing to melanoma if they are not removed. Also, some patients may have multiple atypical nevi as part of the Familial Atypical Mole and Melanoma (FAMM) syndrome. Patients with FAMM syndrome may have dozens, or even hundreds, of atypical nevi, and are at significantly increased risk of developing melanoma.

After a biopsy is performed, a pathology doctor will look under the microscope to see how deeply the melanoma (http://www.cancercenter.com/melanoma.cfm) invades into the various different layers of the skin. They will also look at other factors, including how thick the tumor is, whether or not there is ulceration of the tumor, as well other important factors. For a melanoma to be considered “invasive,” the tumor has to invade deeply enough into the upper layers of the skin where lymphatic vessels are present. (Like many types of cancer, melanoma can easily spread through these lymphatic channels, and then on to the lymph nodes.) If the melanoma tumor only involves the most superficial skin layer, and not the layers that contain lymphatic vessels and blood vessels, then it is referred to as “melanoma in situ.” Unlike invasive melanoma, melanoma in situ (“non-invasive” melanoma) does not have the ability to spread (metastasize) to other areas of the body.

For stereotactic biopsies and MRI-guided biopsies, I use a vacuum-assisted device.

For ultrasound-guided biopsies, I have found both core needles and vacuum devices to be equally successful in my experience, although the scientific literature reports fewer false-negatives with the vacuum-assisted devices. I prefer to use the smaller, less expensive, less scary core needle when possible. If a lesion is very small or subtle on the sonogram, I tend to use the vacuum-assisted device to obtain larger specimens and ensure adequate sampling.

If the target for biopsy is microcalcifications, the adequacy of the specimen can be confirmed by doing a modified mammogram on the obtained specimens, to make sure that calcifications are within the tissue being sent to the pathologist. For masses and other types of biopsied lesions, it’s a bit trickier. For all biopsies, the amount of tissue collected can be visually assessed by the doctor performing the biopsy. For ultrasound-guided biopsies, the needle can be seen in real-time on the screen, and the doctor can see the biopsy needle going through the sampled lesion. For an MRI-guided biopsy, the MRI images taken with the biopsy needle in position are important for confirmation of appropriate tissue sampling. Knowing that there is always room for sampling error by the needle, most radiologists recommend six-month follow-up imaging of the biopsied breast, to confirm that the area biopsied has not changed in any significant way. In addition, when the radiologist receives the pathology report from the biopsy, he/she decides if this result from the pathologist is “concordant” with the imaging findings. If the pathology is not an acceptable answer for the radiologist’s findings (discordant), the radiologist will recommend that the lesion be taken out surgically to confirm benignity.

Over the past 20 years, the standard of care for sampling suspicious lesions in the breast has evolved from open surgical biopsies to the modern standard of minimally-invasive needle biopsy. Over many years, studies have confirmed that needle biopsies are as accurate as surgical biopsies in diagnosing breast cancer, and the needle has advantages: no operating room visit, less invasive, minimal if any scarring, no stitches, fewer complications, less expensive, quicker to perform. In addition, if cancer is diagnosed with a needle biopsy, the patient will have a greater chance of having just one surgery. (If the cancer is diagnosed on a surgical biopsy, the patient usually has to return to the operating room a second time to get all of the cancer out, and to sample the lymph nodes under the arm.) Although most biopsies can be performed with a needle, approximately 10% of biopsies must be performed surgically. The reasons include: living in a region where there are no specialists trained to perform the needle biopsy; the location of the lesion might be in a part of the breast that the needle cannot safely reach; patient inability to cooperate with positioning for the needle biopsy; medical conditions that make direct control of bleeding in the operating room necessary; a breast that is too small or large to allow for the biopsy to be performed with a needle; the presence of an implant, which might not allow for a needle biopsy without a high risk of rupturing the implant.

A stereotactic biopsy is a form of needle biopsy. "Stereotactic" refers to method in which we will image the finding, in order to guide the needle. A stereotactic biopsy is the way we biopsy a mammogram finding, it is not used for ultrasound or MRI findings. If the finding is a cluster of calcifications found on mammography, this will be the preferable mode of biopsy. Nodules are often seen both on mammography and sonography and then an ultrasound guided biopsy is faster, cheaper, and more comfortable for the patient. When we refer to a stereotactic biopsy most facilities are using a vacuum-assisted devise (needle) but this is not part of the definition of stereotactic. A vacuum-assisted devise is particularly beneficial when sampling calcifications, as quantity of tissue retrieved will contribute to accuracy of the diagnosis. This is not necessarily the case for masses.

The first thing to realize, is that the term "biopsy" often means different things to different people, so hopefully I can provide some clarification as well as some advice to women who might be in this situation.

It used to be that when a woman felt a lump in her breast, she was given one option - surgery. The lump was removed, and depending on the results she either was told to resume routine follow up (if it was benign) or had a mastectomy (if it was cancer) - women used to sign a consent form that would allow for lump removal and mastectomy all at the same time if the pathology showed that it was cancer. At the time, we did not have the sophisticated imaging and biopsy devices that we do now, and there was only one operation for breast cancer - a radical or modified radical mastectomy.

Thankfully, a lot has changed. Our imaging has significantly improved - ultrasound can be invaluable when dealing with a palpable lump, especially in a young woman, as often we can make the distinction between normal "lumpy" breast tissue, a fluid-filled cyst, or a solid mass. In addition, ultrasound can give us some idea based on the characteristics of the lesion whether a solid mass is benign or malignant, but ultrasound and any imaging test does not take the place of obtaining a tissue sample that the pathologist can review to make a definitive diagnosis.

The standard of care is that minimally-invasive, image-guided biopsies be performed to make a diagnosis, not surgical removal. There are a few situations when image-guided biopsies are not technically possible or are not appropriate, but they can be performed in the majority of cases. If the biopsy demonstrates a benign lesion, the patient may not need surgery at all, or may be a candidate for a minimally invasive method of treatment, such as cryoablation (see my answer on cryoablation for more details). Approximately 80-85% of biopsies result in a benign diagnosis, and we try to reserve the operating room for therapy, not diagnosis.

If the lesion is found to be malignant, further workup such as MRI or other testing might appropriate in order to properly plan the surgery. There are also plenty of studies demonstrating that if surgery is the first procedure performed in the setting of breast cancer, the woman is more likely to require more than one operation either due to positive margins, the need for lymph node biopsy, or other factors. A more appropriate and more cosmetic procedure will be done if the diagnosis is established prior to surgery. This is supported by the American Society of Breast Surgeons (http://www.breastsurgeons.org/statements/PDF_Statements/Percutaneous_Needle_Biopsy.pdf)


As to who should perform the biopsy, surgeon or radiologist - it depends on the individual practice situation and training of the physician. More surgeons are being trained in performance of ultrasound, ultrasound-guided biopsy, and stereotactic (mammogram-guided) biopsy, and the American Society of Breast Surgeons has education, certification and accreditation programs specifically for surgeons. As a surgeon, I would rather perform the imaging and biopsy myself, as I will then have a better appreciation for exactly where the lesion is (more important when dealing with non-palpable lesions), especially if surgery is eventually required. However radiologists do perform the imaging and biopsies as well, and in many situations, work collaboratively with the surgeon.

However the most important point is not necessarily who performs the biopsy (assuming that anyone performing it is qualified), but that whenever possible, a minimally-invasive needle biopsy be performed rather than surgery as the initial procedure.

Sentinel node biopsy involves mapping the breast (or skin in the case of melanoma) to determine which 1-4 (average 2) lymph nodes drain the breast. This allows precise removal of the lymph nodes most likely to harbor metastases form the breast cancer. A standard axillary biopsy is a removal of 1 or more lymph nodes that are abnormal - usually by size criteria. A standard axillary lymph node dissection is the removal of all the lymph nodes in a certain anatomic area (the 3 dimensiaonl triangle between the lateral border of the pectoralis major muscle (anterior border), the axillary vein (superior border), and the lateral border of the lattisimus dorsi muscle (posterior border). There are typically 10-15 lymph nodes under each arm but like most things in biology the number is a bell shaped curve with some people having a few (6 or less) and some people having a lot (30 or more).

The vast majority of women with breast cancer should be getting no more than a sentinel lymph node biopsy. The exceptions are patients that have large (clinically positive) lymph nodes at the time of their diagnosis that have undergone a biopsy of their lymph node that shows cancer(fine needle aspiration or needle core biopsy typically). Women undergoing lumpectomy who have 1-2 sentinel nodes with cancer in them can now forego a completion dissection based on the recent ACOSOG study - Z0011 that was published in JAMA in February. The caveat is that they have to have whole breast irradiation (not partial breast irradiation). Also this does not apply to patients having a mastectomy (with or without reconstruction). If they have a positive sentinel node, they should have a completion dissection.

After a biopsy, there are 4 potential results:
- Everything is normal - Even with this result though, it is important to continue with monthly self-exams, clinical breast exams, and mammograms.
- Not cancer, but you should be rechecked in 4 to 6 months to look for changes. In the mean time, you should also be looking for changes on your own.
- Abnormal but not necessarily cancerous - Sometimes tests may reveal a higher risk for breast cancer, which may result in more frequent testing or consideration of options to prevent breast cancer (i.e. preventative mastectomy, hormonal therapy).
- Cancer - If cancer is diagnosed, next steps are further tests to learn more about the cancer to determine stage, prognosis, and treatment options.