What is Malignant melanoma?
Malignant melanoma is a type of skin cancer that begins in the melanocytes, the cells that produce the pigment melanin which colors the skin, hair, and eyes. It is one of the most dangerous forms of skin cancer because it has the potential to spread (metastasize) to other parts of the body if not detected and treated early. Melanoma is caused primarily by exposure to ultraviolet (UV) radiation from the sun or tanning beds.
Signs of malignant melanoma include the appearance of new moles or changes in existing moles, such as asymmetry, irregular borders, changes in color, a diameter larger than that of a pencil eraser (about 6 mm), and evolution of the mole’s characteristics over time. The ABCDE rule is often used as a guide to recognize the warning signs of melanoma:
- A for Asymmetry: One half of the mole does not match the other half.
- B for Border: The edges of the mole are irregular, scalloped, or poorly defined.
- C for Color: The mole has multiple colors, such as various shades of brown, tan, black, red, white, or blue.
- D for Diameter: The mole is larger than 6 mm in diameter (about the size of a pencil eraser), although melanomas can be smaller.
- E for Evolving: The mole is changing in size, shape, or color over time.
Early detection and treatment of melanoma are crucial for a positive prognosis. Treatment options may include surgical removal of the tumor, sentinel lymph node biopsy, and in some cases, chemotherapy, immunotherapy, or targeted therapy, depending on the stage and severity of the cancer. Sun protection, regular skin self-exams, and professional skin exams are essential for prevention and early detection of melanoma.
Early detection of malignant melanoma
Early detection of malignant melanoma involves a combination of self-examination, professional skin checks, and awareness of the warning signs. Here are steps for early detection:
- Skin Self-Exams: Regularly perform self-exams to check for any new moles or changes in existing moles. Use a mirror to check hard-to-see areas like the back, neck, and scalp. Look for the ABCDEs of melanoma:
- Professional Skin Checks: Schedule regular full-body skin exams with a dermatologist, especially if you have a high risk of melanoma due to a family history, personal history of sunburns, or a large number of moles.
- Know Your Skin: Be aware of your normal pattern of moles, birthmarks, and blemishes so you can more easily notice any changes.
- Use Sun Protection: Limit your exposure to ultraviolet (UV) radiation by wearing protective clothing, using sunscreen with a high SPF, wearing a hat, and seeking shade during peak sun hours.
- Avoid Tanning Beds: Ultraviolet radiation from tanning beds can increase the risk of melanoma. Avoid using them.
- Stay Informed: Keep up-to-date with the latest information on melanoma detection and prevention.
- Act on Suspicion: If you notice any suspicious moles or skin changes, or if you have a mole that is painful, itchy, bleeding, or scabbing, make an appointment with a dermatologist immediately. Remember, early detection is key to successful treatment.
By following these steps, you can increase the likelihood of detecting melanoma at its earliest, most treatable stage.
The treatment of malignant melanoma
The treatment depends on the stage of the cancer, the thickness of the tumor, whether it has spread to lymph nodes or other parts of the body, and the overall health of the patient. Treatment options may include one or a combination of the following:
- Surgical Removal: The primary treatment for melanoma is surgical removal of the tumor. The surgeon will remove the tumor along with a margin of normal skin to ensure all cancer cells are excised. If the melanoma has spread to lymph nodes, a lymph node dissection may also be performed to remove affected lymph nodes.
- Sentinel Lymph Node Biopsy (SLNB): This procedure is performed to determine if cancer has spread to the lymph nodes. A radioactive substance or dye is injected near the tumor, and the first lymph node(s) to receive drainage from the tumor area (the sentinel lymph node) is removed and examined under a microscope.
- Adjuvant Therapy: After surgery, some patients may receive adjuvant therapy to reduce the risk of recurrence. This can include:
- Immunotherapy: Medications that help the immune system fight cancer cells. Examples include ipilimumab, nivolumab, and pembrolizumab.
- Targeted Therapy: Medications that target specific genetic mutations in melanoma cells, such as BRAF inhibitors (vemurafenib, dabrafenib) and MEK inhibitors (trametinib, cobimetinib), often used in combination.
- Chemotherapy: The use of drugs to kill cancer cells, although this is less common for melanoma and more often used for advanced stages or in combination with other treatments.
- Radiation Therapy: Used to kill cancer cells that remain after surgery or to treat melanoma that has spread to other areas, such as the lymph nodes or distant organs.
- Palliative Care: Provided to improve the quality of life for patients with advanced melanoma, focusing on relief from symptoms and stress.
- Clinical Trials: Patients with melanoma may be eligible to participate in clinical trials, which can provide access to experimental treatments that are not yet widely available.
The treatment plan is individualized based on the patient’s specific situation, and it is important for patients to discuss all options with their medical team to determine the most appropriate course of action. Regular follow-up appointments and monitoring are essential after treatment to check for recurrence or new melanomas.
Drugs used in the treatment of malignant melanoma
Several anticancer drugs are used in the treatment of malignant melanoma, and their effectiveness can vary depending on the individual patient’s condition, the stage of cancer, and other factors. Here are some of the commonly used medications and their general effectiveness:
- Immunotherapy:
- Ipilimumab (Yervoy): This drug works by blocking a protein that prevents the immune system from attacking cancer cells. It is approved for patients with advanced melanoma and can extend survival, but it can also cause significant side effects.
- Nivolumab (Opdivo) and Pembrolizumab (Keytruda): These are checkpoint inhibitors that block the PD-1 protein, allowing the immune system to better recognize and attack cancer cells. They have shown high response rates and improved survival in patients with advanced melanoma.
- Targeted Therapy:
- BRAF Inhibitors: These drugs target cancer cells with a specific mutation in the BRAF gene, which is common in melanoma. Examples include vemurafenib (The most notable manufacturer is Genentech, a subsidiary of Roche. Genentech markets vemurafenib under the brand name Zelboraf. ) and dabrafenib (Tafinlar). They can significantly shrink tumors and prolong survival in patients with BRAF-positive melanoma.
- MEK Inhibitors: Used alone or in combination with BRAF inhibitors, these drugs block another protein in the same pathway. Examples include trametinib (Mekinist) and cobimetinib (Cotellic). Combining a BRAF inhibitor with a MEK inhibitor can improve effectiveness and reduce the risk of drug resistance.
- Chemotherapy:
- Dacarbazine (DTIC): This is a traditional chemotherapy drug that has been used to treat melanoma, but its effectiveness is limited, and it is less commonly used today due to the availability of more effective treatments.
- Combination Therapies:
- Combining immunotherapies, targeted therapies, or both, is an area of active research and shows promise in improving outcomes for patients with advanced melanoma.
