Home > Finding Melanoma Early: When a Lesion Could Be Melanoma

Note: The following FAQ section about the dermatology referral, biopsy, and follow-up experience was written by Louis Neipris, M.D., a medical writer trained in pathology and internal medicine. (The Melanoma Stages 0–IV chart was updated independently.) Dr. Neipris contributes articles covering a wide range of topics in preventive medicine, clinical trial research, and health information quality.

The best cure
for melanoma is
early detection

MEF has received questions from people asking about what to expect if their doctor finds a suspicious lesion, the experience of visiting a dermatologist, and getting a skin biopsy. Below are some representative questions, followed by responses based on my review of the medical literature. I also draw from patient care experience, knowledge as a pathologist trained to interpret skin biopsies, and discussions with dermatologists. Note the reminders to check your skin monthly as well as references to other parts of this website. These are included to reinforce a central message: The best cure for melanoma is early detection.

Could This Be Melanoma?

Q. I have a few moles on my back that haven't changed, but I still watch them closely because as a kid I often got sunburns at summer camp. Last month I noticed a new, small black mole. I just saw my primary care physician, who said it's a pigmented lesion about 6 mm in diameter, and was concerned enough to refer me to a dermatologist. What are the chances this could be melanoma?

A. This patient shares the anxiety that most everyone experiences when referred to a dermatologist for a pigmented lesion, or mole. The patient is doing his best in terms of melanoma prevention, but waiting a month is potentially dangerous when a new lesion appears. It may very well be an early melanoma, but it's impossible to tell without examining the lesion. This case brings up two key points: how to interpret a change found in your skin examination, and the implication of risk factors.

Interpreting a change found in your skin examination: Change can occur in an existing lesion, such as an increase in diameter or change in color, two features that commonly prompt patients to seek medical attention. Itching, bleeding, or elevation are other possible changes you might observe in an existing lesion. Change may also refer to a new lesion that suddenly appears. In this case, the mole may not fall within the ABCDE properties. However, even a lesion less than the diameter of a pencil eraser (6 mm) can turn out to be a melanoma.

Most melanomas progress in two phases: a radial growth phase followed by a vertical growth phase. During the radial growth phase, there is an increase in diameter that poses no risk for spread, and the lesion remains completely curable. Prognosis is primarily based on the vertical growth phase, and the prognosis worsens the deeper the lesion extends beneath the skin.

Nodular melanoma accounts for 15 to 30 percent of all melanomas, and are notorious for rapid downward growth without an apparent radial expansion on the surface. A nodular melanoma can first appear as a small raised mole (perhaps less than 6 mm), when it can be mistaken for not only a benign lesion, but also a blood blister or skin polyp. For those with a chronic skin condition such as eczema or acne, monthly skin self-exams will help tell the difference between yet another outbreak and an early melanoma. Anything that looks "funny" to you should be seen by a doctor. Don't wait. One study even proposed that F for "funny looking lesion" be added to the ABCDE criteria.

The implication of risk factors: Risk factors are always an important consideration, particularly for the case in question. About 10 percent of new melanoma cases diagnosed each year occur in people with a family history of melanoma. The other predisposing risk factors—including a history of excessive sun exposure—apply whether the lesion identified is atypical or not. Here is another mnemonic device for remembering risk factors:

Atypical moles
Many common moles
Red hair or freckling
Inability to tan
Severe sunburn before age 14
Family history of melanoma

In terms of statistics, remember only this important percentage range: 40 to 90 percent. That range is the improved survival rate for people diagnosed with melanoma from the 1940s to the present. The case above presents a patient with the pre-visit anxiety that you too may experience after being diagnosed with a suspicious lesion. Find comfort in the latest figure of 90 percent, the greatly improved survival rate due mostly to increased public awareness about melanoma early detection and monthly skin self-exams.

The Dermatologist Exam

Q. What techniques will my dermatologist use for examining my skin and the lesion in question?

A. A dermatologist has seen hundreds or thousands of cases, depending on how long he or she has been in practice. Experience is therefore the first technique that your dermatologist will use. A simple magnifying glass with a light source and a handheld device called a dermatoscope may be used. Nonetheless, no matter how experienced your dermatologist, reporting your own history is very important and will help guide the exam. Thus, it helps to think about the answers to the following questions prior to your visit:

  • Has anyone in your family been diagnosed with melanoma?
  • Do you have difficulty tanning, perhaps freckling instead?
  • Did you have a lot of sun exposure before age 20?
  • Can you recall over the last few weeks if the lesion has grown, changed shape, become red or irritated looking, or got itchy? Have you seen any new lesions?
  • How many other lesions do you have? Are any larger than a pencil eraser head?

Jotting down the answers in advance will relieve you of the need to think under pressure. Moreover, your answers will provide information that will help your doctor decide how to best treat the lesion.

You can expect a thorough skin check. The doctor or office assistant will ask you to disrobe and put on a hospital gown prior to the exam. All of your skin will be examined and your doctor may ask you questions such as "When did you first notice this lesion?" and "Has it changed or grown?" The more familiar you are with your skin, by doing your monthly skin self-exams, the easier you will find it to answer these questions.

You may also have your lymph nodes checked. Lymph nodes are tiny organs, embedded as clusters within fatty tissue, that help fight off infection. They may collect and trap melanoma cells that spread outside of an advanced lesion. Your doctor will check for palpable lymph nodes—feelable lumps under your armpits and around your neck, if the lesion is on your arm. Lymph nodes in your groin area and upper/inner thigh will be checked if the lesion is on your leg or foot.

Any suspicious lesion will first
be measured and photographed
for a basis of comparison.

Any suspicious lesion will be measured and photographed for a basis of comparison. A Wood's lamp, a kind of magnifying glass with a light source, is often used to characterize surface features, especially color variations. Newer, noninvasive techniques using handheld microscopes called dermatoscopes, or ELM (epiluminescence microscopy) are commonly used to help determine subtle color or contour variations on the surface. These handheld devices, first introduced in Germany, are now in fairly widespread use among dermatologists in the U.S. They help differentiate between lesions that may be confused with benign skin conditions or certain types of much less aggressive skins cancers from those that are malignant melanoma. They can improve detection of melanoma significantly, but a dermatologist would likely still biopsy a lesion with any unusual characteristics. Digitized, or computer-enhanced methods tied into the handheld microscopy information are less common but used by some centers for early detection in patients with multiple lesions.

The Skin Biopsy

Q. What does a skin biopsy involve?

A. A skin biopsy is a surgical procedure for the removal of a piece of skin that is sent to a pathology lab for a microscopic exam and other tests to determine whether a lesion is cancerous. Most biopsies are done under local anesthesia, often using injected lidocaine, a numbing medication. With large, congenital lesions, the surgery is a more complicated procedure done under general anesthesia that may need to be performed in more than one stage and involve reconstructive techniques, including skin grafting. If the lesion is on the face or eye, a similar multistaged approach is used by a plastic surgeon, depending on the size of the area.

Most lesions can be removed on the day of your referral visit. An outline of the area surrounding the lesion is drawn in ink, and the center is marked with a dot. This "mapping" step not only guides the dermatologist in conducting the biopsy, but also the pathologist who receives the specimen and must determine where the margin is located when examining it under the microscope.

The most common biopsy performed on a lesion is a simple excision. The entire mole is removed, along with normal skin and underlying tissue surrounding it. The amount of skin and tissue removed depends on your doctor's suspicion that it is a melanoma, and how deep it is. At minimum, the lesion will be biopsied with a margin of 0.5 cm. The depth of the biopsy depends on where the lesion is located, but generally the removal will extend down to the upper adipose, or fatty layer.

A punch biopsy involves taking a core specimen from a larger lesion that itself cannot be excised by a simple, one-step procedure. The punch biopsy device is a hollow tube, about 5 mm in diameter, with a sharp end used to penetrate the skin deep enough to get under the lesion. The pathologist will determine if the specimen is a melanoma, and how deep it goes. You would then return for a full excision that would require more extensive surgery.

If the lesion is 6 mm or greater in diameter, with elevation or some bleeding, you would likely undergo a biopsy with larger margins (1 to 2 cm) during the first office visit. Remember, the earlier you have the biopsy done, the better.

What to Watch For After the Biopsy

Q. What should I watch for after the biopsy while waiting for the follow-up appointment with my dermatologist?

A. You will be given post-surgical instructions to care for the biopsy site and told what to watch out for. There will be some swelling and redness, and possibly some pain, but simple surgical excisions are not usually associated with complications. Most of the sutures are under the skin and do not have to be removed because they are absorbed by natural processes. Although rare, an increase in swelling, pain, and warmth at the biopsy site are signs of infection.

Waiting for the Pathology Report

Q. Why do I have to wait over a week for the pathology report?

A. Your wait for the pathology report depends on two main factors: the lab's turnaround time and the complexity of the case. It takes at least a day for the specimen to be received and processed, and larger specimens remain "fixed" overnight. This means the specimen is immersed in a solution that will assure proper preservation of cell structure for optimum diagnosis under the microscope. If there is some question as to whether the lesion is a melanoma, the case may need to be examined by more than one dermatopathologist, a pathologist who specializes in reading skin biopsies. Procedures are followed to establish a differential diagnosis between melanoma mimics and actual melanoma. The additional testing does add to the delay. While it may be frustrating, understand that all the necessary evidence is required to enable the best possible reading of your biopsy. A few days wait is therefore in your best interest.

Pathology Report: Melanoma

Q. The word "melanoma" was in my pathology report. I know that means I've been officially diagnosed with melanoma. What now? What should I ask about in my pathology report?

A. The biopsy may have cured you. Again, the earlier the lesion is found, the more likely you will remain free of melanoma because you have had the lesion removed. However, even for the very earliest melanoma tumor you will have to return to your doctor to discuss the biopsy results.

The report's most important comments concern the diagnosis (is it melanoma or not?), margins around the lesion, and depth of invasion, if any. Answers to the following questions will help you understand the implications of your pathology report:

  • What did the pathologist call the lesion?
  • Is the lesion benign or malignant? Benign means that the lesion is neither melanoma nor any other type of cancer. However, a melanoma look-alike will still have to be followed more closely than a benign lesion.
  • Are the margins of the biopsy "clear?" The report will state whether the lesion was fully excised or if tumor cells were seen at the margin. Think of the margin as the boundary between the piece of skin removed and what is left in your body. Ideally the margins are clear, or free of the tumor. If tumor cells were found at the margin, another excision will be required. This second procedure is intended to remove all of the localized tumor left behind. Even if the margins were found to be clear, most dermatologists recommend excision of additional tissue (a narrow area excision) as a precaution.
  • How deep does the lesion extend? If the melanoma cells extend just into the uppermost layer of skin (the epidermis), it is referred to as melanoma in situ, or Stage 0. If all the margins are free of melanoma cells, you are cured. However, your dermatologist may still want to see you every six months for up to two years. Any deeper extension of tumor requires some kind of additional care depending on the depth of invasion and whether you have risk factors (see the MMRISK list above).
  • Is the lesion ulcerated? Tumor thickness and the presence or absence of tumor ulceration are important prognostic factors that are always mentioned in the pathology report.

Melanoma Staging

Q. What is involved in melanoma staging?

A. Step 1: Assess the size and depth of tumor. As mentioned above, first your doctor will determine the size, depth and local spread of tumor based on the pathology report, which in turn will determine your follow-up care. If you had a melanoma in situ completely excised, you are cured. Your dermatologist may want you to return for follow-up appointments for up to two years, but you need not worry about the cancer spreading, even if you have a family history of melanoma.

Step 2: Consider lymph node dissection. A surgical procedure called a lymph node dissection helps determine spread of tumor with the use of a sentinel node, the first lymph node(s) that may contain cells from the tumor. Lymph node dissection for melanoma is still controversial, and is therefore elective lymph node dissection, or ELND. Some studies show that patients with a melanoma between 1 to 4 mm thick may benefit by having an exploration and removal of the lymph nodes in the area that drains the blood from the primary tumor site, even if there is no lump found in the lymph nodes. If a melanoma of intermediate thickness (1 to 4 mm) is found, there may be an improved survival rate following lymph node dissection. However, other studies have shown that ELND does not influence survival, and may cause problems such as swelling in the arm or leg the lymph nodes were removed from.

To locate the sentinel node, a blue dye is injected into the area of the biopsy and allowed to circulate into the lymph node region that corresponds to the area of possible spread of melanoma cells. The surgeon will examine all the lymph nodes and locate the inked sentinel node, but will likely remove only that one and a few others in its region.

The pathologist then examines the removed node(s) under the microscope, looking for groups of melanoma cells. Polymerase chain reaction, or PCR, is a laboratory test for amplifying small quantities of biological molecules (such as DNA or RNA), and may be performed on cells that appear normal, but could contain trace amounts of proteins that are present in melanoma cells.

Step 3: Look for distant spread with imaging procedures. For Stage II or greater, you will have an X-ray and CT scan of the chest and abdomen to look for spread of the melanoma. You may also have an MRI exam. Unfortunately, melanoma can spread virtually anywhere in the body; all major organs are examined, and a head CT scan may be performed if there is evidence of neurological problems.

Blood Tests: Certain blood tests are performed to help determine tumor spread to the liver or bones.

Determination of tumor characteristics and spread:

Restricted to top layer of the epidermis


In epidermis, up to 1 mm thick without ulceration*


Up to 1 mm thick with ulceration*
Stage IIA
In dermis, 1.01 to 2 mm thick with ulceration, or 2.01 to 4 mm thick without ulceration*
Stage IIB
In subcutaneous layer, 2.01 to 4 mm thick with ulceration, or more than 4 mm thick without ulceration*
Stage IIC
More than 4 mm thick with ulceration*
Stage IIIA
Any thickness, without ulceration but with micrometastases in one to three nearby lymph nodes**
Stage IIIB
Any thickness, with or without ulceration, but with visible metastases in one to three nearby lymph nodes or with visible in-transit or satellite metastases**
Stage IIIC
Any thickness, with or without ulceration, but with visible metastases in one or more nearby lymph nodes, sometimes in combination with visible in-transit or satellite metastases**
Stage IV
Any metastasis to distant sites in the body (skin, lymph nodes, subcutaneous layers, or vital organs)

Pathology Report: Atypical Nevus

Q. My biopsy results were not entirely normal; I was diagnosed with an atypical nevus. What can I expect now?

A. A few lesions can be a tough call for the pathologist. Atypical nevi and certain other lesions are not melanoma, but still require close follow-up. You may require doctor visits every three to six months to check the area biopsied as well as other atypical lesions that have not been biopsied, especially if you have a family history of melanoma or other risk factors.

In the meantime, continue to check your skin monthly and pay close attention to the area biopsied. Report any changes, such as the appearance of a new lesion. Also pay close attention to other lesions that your doctor may have pointed out to you on the day of biopsy, but did not think were suspect enough (lacked the ABCDE properties) to remove.

A biopsy for a small lesion
is a minor surgical procedure that could save your life.

If you have a family history of melanoma or have family members with several suspicious moles that are being followed closely (familial melanoma/dysplastic nevus syndrome), you must avoid sunbathing. If you have several lesions that may fit some ABCDE properties, it is not practical to remove them all. You need special instruction on changes to look for within a new or existing lesion. Fortunately, changes that occur if they develop into melanoma are noticeable. Between your own monthly self-skin exams and close follow-up with your dermatologist (who will take serial photographs of the lesions), you will be able to track changes and determine the need for more biopsies. Remember, biopsy for a small lesion is a minor surgical procedure that could save your life.

Pathology Report: Normal

Q. My dermatologist said that my skin biopsy results were perfectly normal and that I don't require follow-up. Yet I'm still concerned about my other moles. What should I do to convince my doctor to see me again?

A. Family history of melanoma or other MMRISKs means you should be seen in three to six month intervals, especially if you have other atypical moles or many lesions acquired as an adult. You should not have to convince your doctor to see you that frequently. Continue with monthly self-skin exams no matter what. Even without a family history or any other moles, check your skin. No one knows your own skin better than you. Most cases of melanoma are diagnosed early and are curable if found early. Remember the 90 percent survival rate mentioned earlier. That figure, of course, depends on you doing monthly self-skin exams. The effort could save your life.