As can be seen from the Web-site subsection, Predicting Skin Cancer Behavior, the only way to truly know what a lesion, possible precancer or cancer is, is to biopsy it, i.e., to obtain a specimen for microscopic examination.

A skin biopsy is the removal from the body of any piece of skin or tumor tissue that is to be sent to a laboratory to be stained and examined under the microscope. A biopsy may be large or small. A biopsy may be an incisional biopsy, i.e., the taking of a piece of a tissue smaller than the skin area about which the doctor is concerned, in order to get an idea of what the process is. An excisional biopsy is the taking of the problem area of skin or lesion plus some extra normal tissue (margin) around what the naked eye sees as abnormal, in the hopes of trying to remove all of the targeted process. For most dermatology purposes, to biopsy is to remove a tissue sample in order to make a diagnosis. To see whether some lesion, cancer, tumor or growth has been entirely removed, doctors talk about testing the removed tissue. That act itself is technically the biopsy, but the distinction is not well understood by the public.

The author has developed techniques to make the taking of a biopsy specimen virtually painless for most locations. The sample taken is smaller than the head of a pin, resulting in a mark that is very difficult to detect, as biopsies go. The biopsied area usually heals in one to two days, and the results are accurate and reliable. If biopsies are not easy for patients to tolerate, then patients may not come in when a cancer is suspected. The author believes that simplicity and accuracy of biopsy technique is as important as a good skin-cancer removal technique.

The Web-site author believes that it is rarely necessary to take pieces of suspected basal-cell carcinoma larger than a pinhead for a biopsy. If a squamous-cell carcinoma is suspected in a lesion and is the size of a pencil eraser, a biopsy of less than one-third its size, but including the depth in the inverted pyramid, is usually sufficient. If melanoma or a bad (suspicious for atypia) mole is suspected, the author may take a sample much smaller than the mole. If the lesion is large, he may occasionally take two or more samples within the lesion. In all of these cases, the author uses the inverted-pyramidal-biopsy technique he developed. This technique allows the skin to heal with only a virtually imperceptible Mercedes sign that, many times, cannot be found even by doctors looking for the site. Because of the extreme difficulty in finding old biopsy sites using the inverted pyramidal technique, the author and his staff measure by compass every biopsy site from a set of fixed points on the body. Knowing a lesion's coordinate location aids in finding the biopsy site days or weeks later, should there be a positive result. Tiny biopsies are usually well-tolerated by patients; still, they must be of sufficient size to provide the laboratory with adequate information. If the lab tells a doctor that more than one in every hundred specimens needs to be retaken, then that doctor should improve his/her biopsy technique. The tiny biopsies that result from the author's inverted-pyramidal-biopsy technique may have make-up applied to them within hours for social functions, heal in days and may be taken swimming immediately.

Although a biopsy may be used to test any kind of skin growth, we will consider the extremely common example of the mole. Most dermatologists feel that if a mole is changing or suspicious for malignancy, a biopsy should be performed. There are many ways to biopsy many types of moles, all varying in cost and scar formation. The author is specially trained in all the existing forms of mole removal. The author's philosophy on mole removal is that margin excision (the removal of large pieces of normal tissue) around moles, thereby leaving large scars for initial testing is NOT helpful. A small inverted-pyramidal sample is best. Also, the inclusion of extra normal tissue in a large specimen makes it more difficult for the average laboratory technician to examine a mole thoroughly. As you can see, the author favors incisional biopsies rather than excisional biopsies for evaluation of a spot or process (lesion).

An INCISIONAL BIOPSY is the taking of a piece of a tissue smaller than the lesion (skin area in question) in order to get an idea of what the process is. The specimen is examined under the microscope, in most cases after it is stained with special dyes that usually display the nucleus and nuclear material as well as other parts of the cell(s). Incisional biopsy techniques may include punches with a miniature sharp cookie-cutter like instrument, shaving, snipping with scissors, the author's special inverted-pyramidal-technique and partial scalpel sampling.

In the author's office, FOR INITIAL EXAMINATION or incisional biopsy, a tiny inverted-pyramidal biopsy is taken of small moles. Moles that protrude are tangentially sampled (delicately removed to the level of the skin), and the remaining skin surface is then lightly sanded to match the surrounding body contours. Though the biopsy is small, it usually encompasses 90% of the mole cells. If the biopsy is read benign, then no further work is necessary. If the biopsy indicates any potential for trouble in the future, then the patient is advised of the options and a final decision made for or against a margin excision to remove any remaining mole.

Is it dangerous to leave any part of a "bad mole" behind? Isn't it better always to sample moles with a margin excision to avoid spilling potentially malignant cells into the bloodstream? The answer fortunately is NO! British and American Dermatologists have battled over this question for years and detailed studies of large and small melanoma biopsies resoundingly favor the American view that small specimens are not dangerous. These studies have shown that melanoma sampled by small biopsies does not spread cells into the bloodstream to any greater degree than melanoma sampled by taking large margin excisions. Melanoma is derived from cells similar to a mole. One of the deadliest forms of skin cancer, if melanoma is not spread from small samples, then it can be reasonably inferred that other moles are not spread by small sampling.

The proposed small incisional (inverted pyramidal) biopsies that the website author discusses do not apply to all patients or all moles. Your doctor will likely have good reasons for recommending his/her approach. Nothing is etched in stone when it comes to biopsying moles and suspected melanomas. Some moles are so obviously "bad looking" that the surgeon should excise (cut all around) these moles so as to make it easier for a good dermatopathologist to inspect it under the microscope for deep invasion. Some patients "want it all over with at once" and demand the spot be completely cut out, whether or not it is benign or malignant. Again, there are many different factors that go into the choice of whether to cut around or into a "pigmented lesion" or for the purposes of this chapter a "colored, irregular spot or bump." No one treatment or type of biopsy is right for everyone. There are two sides to every story and it is only fair for the website author to criticize the use of an incisional biopsy (such as a punch, inverted pyramidal, shave, etc) in evaluating pigmented lesions.

Certain well-respected dermatopathologists such as Dr. Raymond Barnhill believe that every suspicious pigmented lesion (mole) should be biopsied by completely cutting the growth or spot out of the body. This argument has its merits. First, not all bad pigmented lesions (spots) have the most severe abnormal cells in the areas that most doctors can easily identify as bad portions of the mole. Second, the bigger excisional biopsy may "cure" the spot if it is mildly atypical and of course if it was benign from the beginning. Third, dermatopathologists are heavily looked upon following the reading of a melanoma to come up with a number that determines the Breslow level which largely determines a patient's chances for survival. It would of course be impossible for dermatopathologists to provide a reliable thickness answer if they have been given only a small portion to represent the entire "bad spot." Reading only partial or incisional biopsies of spots suspicious for melanoma is an extra burden for dermatopathologists who pride themselves on accuracy. These are extremely valid reasons for performing excisional samples or biopsies. Many dermatopathologists are purists. This approach however may be one that takes only the individual mole into consideration and not the public in general or individual patients.

The website author respects the philosophy of these expert dermatopathologists. However, the website author is at odds with the above philosophy in the majority of his patients for the following reasons. First, cutting out all moles on patients who have anything "suspicious" costs a lot of money, patient transportation, lost work, lost wages, lost productivity, pain of needles (although this can be made extremely minimal), wound care, stitching, etc. Many times managed care only compounds these problems. Not all melanomas are extremely or even moderately abnormal looking. Performing excisional surgeries that cause scarring sometimes an inch or more long limits the amount of moles most patients will want checked or tested in a lifetime. Remember, even in the age of epiluminescence microscopy, the best test for melanoma is a skin biopsy that is read under the microscope. The public and especially the cosmetically conscious patients of the website author do not want numerous noticeable scars on them if at all possible. Tiny incisional biopsies used by the website author have many uses. These incisional biopsies act as a simple "screening tool" because they leave almost unnoticeable marks, allow patients to immediately cover them with make-up, allow immediate return to sports and other activities, are low cost, take less than 20 seconds to do, allow immediate return to work, do not upset the patient's looks, require no stitch removal and still provide some very useful information. Larger excisional biopsies are less of a "screening tool" because they do not share the benefits we just mentioned of tiny incisional biopsies. Judging from the A, B, C, D's put out by the Skin Cancer Foundation and the American Cancer Society and all the other screening programs and from the fact that melanoma is most curable when found early, it seems only logical that the more screening methods, the better.

If an incisional (inverted pyramidal) biopsy is read as "moderately" or "severely" atypical under the microscope, which is rare in itself (only 5 ­ 10% of the website author's pigmented lesion biopsies) then an excisional surgery mole removal (which becomes a biopsy and is checked by the laboratory) will be scheduled. If original incisional mole biopsy is read "mild" then the mole will be observed indefinitely (if the patient desires) with annual body checks or suggested to be removed if the mole is in a location that cannot be easily seen by the patient. Since so few incisional biopsies would result in some sort of follow-up excisional surgery, incisional biopsies can be thought of as a tool of mass screening that may end up gaining more information (by wider acceptance and use) than they lose (less ability to determine depth on initial sample). Additionally, since the samples are so small especially at the deeper portions when discussing the inverted pyramidal technique the mole is not disrupted much for a later excisional biopsy. Since the inverted pyramidal technique acts as a scout while causing minimal distortion to the remaining mole or melanoma it may best be considered a special type of incisional biopsy. Additionally, the website author has been very fortunate in telling which areas of a mole may be "bad", never having lost a patient to melanoma in over a decade of practice dedicated to skin cancer and skin cancer surgery. Warning: not all doctors may be good at the inverted pyramidal technique.

The website author can certainly agree with the dermatopathologists concerns when it comes to incisional biopsy techniques that may damage or partly destroy what remains of a suspicious pigmented lesion. In those cases it may be better to "scout" with the more involved excisional methods to avoid disasters like missing the worst section of the mole, etc. Additionally, when the varying skills of other doctors come into play using the inverted pyramidal technique there may be difficulties as well. We again must humbly respect the thoughts of the puristic dermatopathologists who recommend only excisional removal of moles. Perhaps they have seen too many serious problems as a result of reading thousands of other dermatologists' and plastic surgeons' mole and melanoma biopsies.

If a protruding mole looks benign and must be removed due to irritation or to enhance cosmetic appearance, a technique called tangential incisional biopsy may be performed. This consists of "shaving" the mole with a sharp scalpel parallel to the surface of the skin, followed by a light sanding. This biopsy removes the raised portion of the mole, leaving some mole cells in the skin. Less than ten percent of the time, these remaining mole cells will re-grow the mole, sometimes even darker than before the biopsy. The tangential biopsy wound generally heals within two to three weeks as a flat scar approximately the same size as the original mole. Initially, the scar can be pink, darker or lighter than the surrounding skin. This color tends to blend in with time leaving a barely perceptible scar. Darkening of the site is minimized if the patient avoids sun exposure or uses at least a #15 sunscreen to the area for several weeks after the biopsy. Good wound care of the area is important to obtaining the best cosmetic result.

Healing tendency depends greatly on the individual and can sometimes be unpredictable. Rarely, a raised or depressed scar may develop in spite of good biopsy technique and meticulous care. The best thing to do if one does not know one's healing tendency from previous wounds or surgery, is to remove only one mole first to see what the healing result is, before removing multiple moles for cosmetic purposes. One must weigh the risks versus possible benefits. If a raised scar does form, local steroid injections and massage are usually effective treatment.

All moles removed, even benign-looking ones, should be sent to pathology for microscopic examination to tell us whether, if fact, the mole is harmless. Sometimes moles that are textbook examples of benign or "good" moles turn out to be serious melanoma, discovered incidentally. This is because ten percent of melanomas may not fit the classic dermatologists' rules for malignancy.

The patient can participate actively in his/her own care by self-examination. Signs of concern for melanoma include a mole's recent change in appearance, size, shape or color, irregularity in color, loss of a uniform border, asymmetry, bleeding, and notching of a border. Moles with any of these signs should be brought immediately to the attention of a dermatologist for close scrutiny of the lesion.

An EXCISIONAL BIOPSY may be taken to determine the nature of a particular growth or lesion, but it is usually performed to determine whether any of the growth still remains in a patient. At the extreme ends, both vertical sections (standard surgical excision) and horizontal sections (Mohs Surgery) are excisional biopsy techniques. The author prefers to use those excisional techniques to remove a known lesion rather than merely for analysis. An excisional biopsy is the removal of surrounding normal tissue in addition to a suspected visible lesion in the hope of removing any and all small cells of the lesion which may be spreading out and invisible to the naked eye.

Excisional specimens involve creating a margin or buffer of skin that appears clinically (to the naked eye of the surgeon) to be normal around the lesion in question. Many medical textbooks/doctors feel that all moles should be excised with a 2-3 mm margin (are around them). Many authorities feel that most basal-cell cancers can be removed with 90% confidence or 10% risk of failure by taking 3mm (1/8 of an inch) of normal tissue around the clinically visible basal-cell cancer. Some newer studies suggest that squamous-cell skin cancer may require a 5 mm border of normal tissue excised in order to be assured of the cure at least 95% of the time (meaning about 5% will be missed). Excisional surgery is likely the treatment of choice for melanoma in many other conditions. See Melanoma.

Standard surgical excisional specimens, although popular, may lack both diagnostic and margin determination accuracy. Yet, most dermatologists, including the author in selected instances, and all plastic surgeons use this technique. The lack of accuracy arises because, in many cases, the tumor that is visible on the skin surface may be only the tip of the iceberg. Standard surgical excision (standard surgical excisional surgery, vertical sections, excisional biopsy with vertical sections) suffers (lacks) in accuracy for several reasons. First, the surgeon must guess by looking at the surface of the skin where the tumor begins and ends. Then, the surgeon must mark off and cut out, usually in the shape of a cylinder or an ellipse (football), an extra amount of bordering normal appearing skin. The surgeon sends this specimen to a pathology lab. The reasoning is that if a tumor process involves the edges of the tested specimen, it is highly likely that the process (be it tumor or abnormal growth) involves the edges of the tissue that remained behind in the body from where the specimen was taken. The problem is accurately determining whether the tissue sent to the lab involves the actual edges of the tumor.
......The laboratory may attempt to use different methods to check that the tumor has been fully removed. This is where the greatest difficulty lies. For example, the most common excisional-specimen testing method is "bread-loafing." Just like "Holsum® Bread," the specimen is cut into slices. But instead of 30 slices, which would cost hundreds of dollars, the tissue specimen is usually cut into five slices. If the pathologist can look only at a few individual slices of tissue, he/she might miss tumor in one of the remaining slices. Unfortunately, vertical sections test only a small portion of a specimen's edges and therefore have an inherent failure rate or uncertainty rate. By questioning most surgeons, you will see they do not know this important fact. Vertical sections were the cause of the plastic surgeon's missing the basal-cell skin cancer on President Reagan's nose the first time. There is a proven inherent failure rate with vertical sections. Horizontal section testing (Mohs Surgery) is much more accurate. So when the doctor or pathologist using vertical sections says, "It's out," he/she really means to say "It's out to the best of our knowledge, using a particular method."

The author prefers these excisional techniques of horizontal and vertical sections only for the purpose of removing a known lesion rather than merely for analysis, i.e., for diagnosis (determination of the nature of the lesion). Assume, for the sake of argument, that a new patient appears with four areas suspicious for skin cancer, two of which are truly squamous-cell cancer. Taking four, 30 second, fast healing incisional biopsies to find out which two spots are cancer is far preferable to charging four to eight times the incisional biopsy cost, cutting out excisional biopsy margins, sewing the holes, having the patient care for the wounds for a week and removing the stitches, subject to the possibility that the lab has missed cutting or analyzing the center of the larger excisional specimens.

There are many ways to biopsy a given lesion on a particular patient. Each lesion presents its own set of difficulties. Your surgeon will likely do his/her best to explain the answers to any questions you may have regarding skin biopsy.

There are many gray zones in diagnosing and treating skin cancer and it may be best to seek two or three opinions before having surgery or relying heavily on a given biopsy. The first thing to know is whether the biopsy (pathology or histopathology) was read correctly. It may be worthwhile to have the glass slide (not just a lab report) read by a different, but reputable, lab before seeking a second surgeon's opinion. Some suggestions are to have the slide re-read at highly reputable institutions such as the Mayo Clinic or a Department of Dermatology at a University Medical School like Harvard or New York University.

The above figure shows an inverted pyramidial biopsy. The blue box represents the dermis. The green amorphous circle represents the top of an unknown growth. The black inverted pyramid is the portion of the growth that is removed by the surgeon. The actual size of the biopsy taken is no more than 1-2 pinheads. The smaller portion of the sample taken is in the deepest part of the dermis. This prevents scarring by doing the least amount of damage to the deep tissue, while still giving the pathologist a reasonably good sample to study.

© 1997-2003, Paul J. Weber, M.D., P.A., All Rights Reserved