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  • A type of skin cancer that forms in the cells that produce skin color
  • Symptoms include a new, unusual growth or changes to an existing mole on the skin
  • Treatment includes surgery, immunotherapy, targeted therapy, chemotherapy, or radiation therapy
  • Involves melanoma program, medical dermatology, dermatologic surgery, onco-dermatology program, dermatopathology
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Too much time in the sun or a tanning booth in your youth might make you worry about skin cancer, especially the most serious form called melanoma. 

It is a type of skin cancer that originates in the pigment-producing cells of the epidermis called melanocytes. Of the three most common types of skin cancer, melanoma is the most dangerous. It's much more likely to spread than basal cell or squamous cell carcinoma to spread.  

Melanoma accounts for only one percent of skin cancer cases but causes a large majority of skin cancer deaths. Rates of melanoma have been rising for at least 30 years. About 96,000 new cases of melanoma are expected to be diagnosed this year. 

But here's the silver lining: “This serious cancer can be—and should be—diagnosed early, when it is usually completely curable,” says David J. Leffell, MD, a Yale Medicine dermatologist, who is the chief of the Dermatologic Surgery and Cutaneous Oncology

At Yale Medicine, we are proven experts in diagnosing and treating melanoma. “Knowing more about melanoma in its earliest stage can save your life or the life of a loved one,” says Dr. Leffell.

What are the risk factors for melanoma?

As with other types of skin cancer, exposure to ultraviolet (UV) radiation, from the sun or tanning beds, is a major risk factor for melanoma. Skin color matters, too. There's an inverse relationship between the amount of pigment in a person's skin and his or her risk of melanoma. 

Not all melanomas are UV related. There's also a genetic component, which involves abnormalities in the gene that directs the body's production of the protective skin pigment known as melanin. Researchers have found that people who have abnormalities in this gene and have red hair and fair skin have a fourfold increased melanoma risk. About 10 percent of all people with melanoma have a family history of the disease (meaning that a parent, brother, sister or child has melanoma). 

The risk of melanoma increases as people age, says Dr. Leffell says. The average age at diagnosis is 62 but, notes Dr. Leffell, melanoma occurs in those under 30, too, and it is one of the most common cancers in young adults—especially young women. (Melanoma that runs in families may occur at a younger age.) 

According to Dr. Leffell, here are common risk factors: 

  • Family history of melanoma
  • Personal history of melanoma or atypical (dysplastic) moles
  • Fair skin
  • A tendency to burn rather than tan
  • Sensitivity to the sun
  • Freckles
  • Red/blond/light brown hair
  • Green/gray/blue eyes
  • Excessive sun exposure
  • New or changing moles

What are the symptoms of melanoma?

The most important warning sign for melanoma is a new spot on the skin or a spot that’s changing in size, shape or color. A spot that looks different from all of the other spots on someone’s skin (for example, it's darker than the freckles or it has a different shape than the other moles) is also something to bring up to a dermatologist. 

While common moles do not turn into melanoma, an "atypical nevus" mole can transform into this kind of cancer, says Dr. Leffell. Self-examination for melanoma is a good place to start, but Dr. Leffell highlights change in color as an important factor. People should look for moles that fit this description:

  • Asymmetry: If you fold the mole over in your mind's eye, the halves won't match, he says. 
  • Border irregularity: The edges of the mole are ragged, notched or blurred, not smooth like normal moles.
  • Color irregularity: There are shades of tan, brown and black. Even red, white and blue can add to the mottled appearance.
  • Diameter: A mole with a diameter greater than a pencil eraser (about five to six millimeters) should raise suspicion.

The most common location for a melanoma to appear is on the back. Men are also highly susceptible to melanomas on the chest or abdomen, while women develop melanomas on the legs more often than do men. 

Dr. Leffell says that patients should trust their instincts. “If you sense there is something of concern about a mole, insist that your doctor biopsy it,” he says. 

Catching malignant melanoma early makes all the difference in terms of being able to treat it. According to the Journal of the National Cancer Institute, people who check themselves for changes in existing moles or new growths and abnormalities are 44 percent less likely to die from melanoma. 

“Self-examination, early diagnosis and immediate treatment can literally save your life,” Dr. Leffell says.

How is melanoma diagnosed?

Because melanoma can appear anywhere on the skin, including areas not commonly exposed to the sun, it's important to get regular annual full-body exams performed by a dermatologist. These exams can detect the spots that a person can't see (for example, on the back or top of the head). 

The definitive diagnosis for melanoma can only be made by taking a skin biopsy. After numbing the area with a local anesthetic, the dermatologist will excise the full depth of the lesion. The thickness of the melanoma is very important because it helps to determine prognosis, says Dr. Leffell. 

“The biopsy needs to be of sufficient depth to ensure an accurate assessment of the melanoma,” Dr. Leffell says. “Since our program at Yale Medicine specializes in skin cancer, we have extensive expertise in both the biopsy procedure and ensuring that the pathology is read by our highly skilled team of skin pathologists.” A properly done biopsy should heal well with a minimal scar.

How is melanoma treated?

Treatment options are based on the stage of the cancer and other factors. Those factors are identified on the biopsy and include degree of inflammation, how quickly the cells seem to be dividing, and other features.  

Early-stage melanomas that haven't grown deeper than one millimeter can be completely treated with office-based excision, or surgical removal. “Ninety-six percent of early-stage melanomas are cured with simple surgery,” says Dr. Leffell. In those cases, the doctor uses a procedure known as a wide excision to remove the melanoma and a margin of skin and tissue extending 1 to 2 centimeters around it to ensure that all of the cancer is removed.

A special area of expertise for Dr. Leffell’s team at Yale Medicine is a sub-category of melanoma called melanoma in situ. This form of melanoma is extremely superficial and has a low risk of spreading. But since it commonly occurs on the face, it presents special treatment challenges. In these cases, surgeons try to use surgical techniques typically used for cosmetic procedures to hide scars.

If the melanoma at the time of diagnosis is deeper than one millimeter or has some concerning features on biopsy, a more complex workup will be required. In those cases, Dr. Leffell and his team would refer the patient to colleagues at Yale Medicine who would perform a sentinel lymph node biopsy to determine if the melanoma has spread.

The sentinel lymph node is the first node where the cancer would be expected to spread, given the flow of the body’s lymphatic system. If that node is clear, meaning there are no cancer cells in it, then it is unlikely that the cancer has spread to other nearby lymph nodes, and further surgery on the lymph nodes is not required. If melanoma is found in the sentinel lymph node, doctors may choose to monitor the status of the other lymph nodes using periodic imaging tests. In other cases, though, the surgeon may remove the remaining lymph nodes in a more extensive procedure called lymph node dissection.

For more advanced cases of melanoma that have metastasized, treatment options include excision plus immunotherapy, targeted therapy, chemotherapy, or radiation therapy (sometimes more than one treatment is used). 

How is the patient monitored after surgery for melanoma?

After the surgery, the dermatologist will create a follow-up schedule of visits, depending on the patient’s situation. For example, says Dr. Leffell, if the patient has melanoma that hasn't spread within the body, he or she will be seen by a doctor every three months for the first year and twice a year from that point on.  

A patient who has had one melanoma is at a higher risk for developing more. That’s why it’s important for melanoma patients to do regular self-checks. Dr. Leffell recommends doing this monthly and adds that a patient should report new lesions of concern to the dermatologist right away. Adequately protecting the skin from the sun is, of course, crucial for melanoma survivors.

What makes Yale Medicine’s approach to melanoma unique?

“Our section's main focus is skin cancer and melanoma,” says Dr. Leffell, who founded this program in 1988 and has also published some of the key research on skin cancer. “One great strength of our program is our close working relationship with our skin pathologists. The diagnosis of melanoma is not always black and white, and having the experience to address the nuances is critical for the patient,” he says.

Special approaches are used in the treatment of melanoma in situ, and the team at Yale Medicine probably has the most experience in the region treating this type of melanoma.

“If the melanoma is more advanced than the earliest stages, or can’t be treated in the office setting, we work closely with our colleagues in Yale Medicine's Departments of Surgical Oncology and Medical Oncology, who assume care of the patient in a seamless fashion,” Dr. Leffell notes.