Among the various types of skin cancer, melanoma is one of the most aggressive and potentially lethal forms. This article covers the essential aspects of melanoma, including its causes, risk factors, detection and preventive measures.

MELANOMA SYMPTOMS

Recognizing the early signs of melanoma can significantly improve the chances of successful treatment. Some symptoms observed:

  • Asymmetric moles: Melanoma lesions are often irregular or asymmetrical. Unlike benign moles that are typically round and uniform, melanoma lesions can have jagged edges and an irregular outline. Monitoring the symmetry of the moles is a key step in detecting potential melanoma.
  • Boundary Irregularities: Healthy moles usually have smooth, well-defined edges. In contrast, melanoma lesions often have uneven, jagged, or blurred edges. Any sudden change in the border of a mole should be examined by a dermatologist.
  • Color Variation: A mole's color can provide important clues. While benign patches tend to be a single, uniform color, melanomas often exhibit a mixture of colors within the same lesion. Shades of brown, black, white, red or even blue may be present. This color diversity is a red flag for possible melanoma.
  • Diameter Increase: Melanoma lesions usually have a larger diameter compared to common moles. If the diameter of a mole exceeds 6 millimeters (about the size of a pencil eraser), it should be examined by a medical professional.
  • Evolution or Change: Any noticeable change in a mole's size, shape, color, elevation, or any other characteristic should be cause for concern. Regular self-exams and an increased awareness of your skin's condition are crucial for detecting evolving melanomas.
  • Itching or Sensation: Melanomas can sometimes cause itching, pain, or a burning sensation. If a mole becomes tender, itchy or painful, it is essential to have it evaluated by a dermatologist.
  • Bleeding or Oozing: Melanomas may bleed, ooze, or crust over. Any unexplained bleeding or fluid discharge from a mole should be promptly treated by a medical professional.

CAUSES

  • Genetic Predisposition: A person's genetic makeup plays a key role in their susceptibility to melanoma. Mutations in certain genes, such as BRAF and CDKN2A, have been linked to an increased risk of developing melanoma. These genes are involved in regulating cell growth, repair, and the body's ability to defend itself against UV radiation damage. Individuals with a family history of melanoma or with specific genetic mutations are at greater risk of developing this skin cancer.
  • Exposure to ultraviolet radiation (UV): Excessive exposure to ultraviolet radiation, primarily from the sun but also from artificial sources such as tanning beds, is a well-established risk factor for melanoma. UV radiation damages the DNA within skin cells, leading to mutations that can trigger the development of cancer. Intermittent, intense sun exposure, often associated with outdoor activities such as sunbathing or outdoor sports , can further increase the risk.
  • Skin pigmentation and sun sensitivity: People with fair skin, light hair and light eyes are generally more vulnerable to the harmful effects of UV radiation. This is due to the reduced amount of melanin – the pigment responsible for protecting the skin from UV damage – in your skin. Consequently, those with fair skin are more likely to get sunburn and have a higher risk of developing melanoma.
  • Atypical moles and nevi: Moles are common skin growths that are usually harmless, but certain types can indicate an increased risk of melanoma. Atypical moles, also known as dysplastic moles, have irregular shapes, uneven color distribution, and larger sizes compared to regular moles. Individuals with numerous atypical moles are at a higher risk of melanoma, as these moles can progress to cancerous lesions over time.
  • Immune Suppression: A weakened immune system can compromise the body's ability to detect and destroy cancer cells, including those responsible for melanoma. Organ transplant recipients , individuals with certain autoimmune diseases, and those undergoing immunosuppressive therapies are at an increased risk of developing melanoma due to their impaired immune responses.
  • Geographic Location: The prevalence of melanoma is usually higher in regions with bright sunlight and higher levels of UV radiation. Countries closer to the equator, where sunlight is stronger, tend to have a higher incidence of melanoma. This highlights the significant role that environmental factors, particularly exposure to sunlight, play in the development of this cancer.

  • Personal history of skin cancer: Individuals who have already been diagnosed with any form of skin cancer, including melanoma, face an increased risk of developing additional skin cancers. This underscores the importance of regular skin exams and surveillance, especially for those with a history of skin cancer.

DIAGNOSIS

  • Clinical examination: A vital step in diagnosing melanoma is a thorough clinical examination by a trained dermatologist. They examine the appearance, size, shape, color, and characteristics of the borders of the suspected skin lesion using the ABCDE rule (Asymmetry, Border irregularity, Color variation, Diameter greater than 6 mm, Evolution over time). Dermatologists can also use the newer "EFG" rule, which incorporates additional features like Lifting, Firming and Growth. This initial assessment helps identify potentially malignant lesions that require further investigation.
  • Dermoscopy: also known as dermoscopy or epiluminescence microscopy, is a non-invasive technique that improves visualization of skin structures that are not visible to the naked eye. A dermoscope , a handheld device with magnification and lighting, is used to examine the surface of the lesion. Dermoscopy helps dermatologists analyze the lesion's pigment network, the presence of dots and globules, striae, and other characteristics that help distinguish between benign and malignant lesions .
  • Biopsy: When a lesion is suspected to be melanoma based on clinical examination and dermoscopic findings , a biopsy is performed. A biopsy involves removing a sample of the lesion for pathological examination. The two main types of biopsies are the punch biopsy and the excisional biopsy . A punch biopsy extracts a small cylindrical sample of the lesion, while an excisional biopsy removes the entire lesion along with a safety margin of healthy tissue. The biopsy sample is then examined under a microscope to determine whether it is cancerous and, if so, to classify its type and stage.
  • Sentinel Lymph Node Biopsy: In cases where the melanoma is more likely to have spread, a sentinel lymph node (SLNB) biopsy may be performed. This procedure involves identifying and removing the sentinel lymph node , which is the first node to which cancer cells are likely to spread from the primary tumor. The presence or absence of cancer cells in the sentinel lymph node provides essential information about the extent of disease progression.
  • Molecular and Genetic Tests: Advances in molecular and genetic testing have revolutionized melanoma diagnosis. These tests look at the genetic makeup of tumor cells and provide information about the genetic mutations and changes that drive cancer growth. Tests such as the BRAF mutation analysis, which identifies a common mutation in melanoma cells, can influence treatment decisions. Furthermore, gene expression profiling helps to categorize melanomas into different subtypes, aiding in personalized treatment approaches.
  • Imaging techniques: Imaging techniques such as ultrasound, CT scan and MRI are employed to determine the extent of spread of melanoma within the body. These imaging methods help with the staging of the cancer and assess whether it has metastasized to nearby lymph nodes or distant organs.

TREATMENT

Several treatment options are available, and often a combination of approaches is used:

  • Surgery: Surgical removal of the melanoma is the primary treatment for localized cases. In cases where the cancer has spread to nearby lymph nodes, surgical removal of these nodes may be necessary.
  • Immunotherapy: This approach harnesses the body's immune system to recognize and attack cancer cells. Immune checkpoint inhibitors and cytokines are examples of immunotherapies used in the treatment of melanoma.
  • Targeted Therapy: Targeted drugs are designed to inhibit specific gene mutations or proteins that contribute to cancer growth. These drugs are particularly effective in cases where the cancer carries specific gene mutations.
  • Chemotherapy: Although less commonly used than in the past, chemotherapy can still be a viable option for advanced melanoma that has spread to distant organs.
  • Radiotherapy: This treatment involves using high doses of radiation to target and destroy cancer cells. It is often used to relieve symptoms in advanced cases of melanoma.
  • Precision medicine: Advances in genomics have led to personalized treatment approaches based on the patient's genetic makeup and the genetic profile of the tumor.

PREVENTION

Melanoma prevention involves a combination of adopting protective behaviors and regular self-exams:

  • Sun protection: Limiting exposure to UV radiation is key. This can be achieved by looking for shade, especially during peak sunlight hours (10am to 4pm), wearing protective clothing, and using a broad-spectrum sunscreen with a high SPF rating.
  • Self-exams: Examining your skin regularly can help identify any new moles or changes in existing ones. The ABCDE rule can guide you: asymmetry, irregular edges, color variation, diameter larger than a pencil eraser and evolution over time.
  • Professional Skin Checkups: Schedule regular appointments with a dermatologist for a thorough skin checkup. Practitioners can detect early signs of melanoma that may be overlooked during self-exams.
  • Avoid tanning beds: The artificial UV radiation from tanning beds is just as harmful as natural sunlight. Avoid using tanning beds to reduce the risk of melanoma.
  • Healthy Lifestyle: Maintaining a healthy immune system through a balanced diet, regular exercise and adequate sleep can contribute to your body's ability to prevent cancer growth.