Melanoma is the most serious form of skin cancer, arising from pigment-producing cells called melanocytes. While it can appear anywhere on the body, its occurrence on the scalp presents unique challenges for detection and treatment. This location is associated with a less favorable outcome compared to melanomas found on the trunk or limbs. The presence of hair and the anatomical features of the head often lead to diagnosis at advanced stages.
Unique Challenges of Scalp Localization
The primary danger of scalp melanoma is delayed detection because hair conceals the skin. Lesions are often hidden from view, meaning they are typically diagnosed at a thicker stage when the cancer has grown deeper into the skin layers. This delay results in a higher median Breslow thickness at diagnosis, which predicts a worse long-term outcome.
The scalp’s underlying anatomy also contributes to the disease’s aggressive nature. The head and neck region is highly vascularized and contains an abundant network of lymphatic vessels. This rich circulation provides melanoma cells with easy pathways to spread quickly to regional lymph nodes and distant organs.
The complex lymphatic drainage pattern in the scalp and neck makes the spread of cancer cells somewhat unpredictable. A scalp location is an independent factor associated with a reduced overall survival rate, even compared to other melanomas on the head and neck.
Identifying Warning Signs
Detecting melanoma on the scalp requires a proactive approach, often involving assistance from a partner, family member, or hairdresser. The widely recognized ABCDE criteria still apply, but they must be adapted for this difficult-to-see location. Regular checks are necessary to monitor moles that show uneven halves, scalloped or blurred edges, or a mix of colors.
The “E” for Evolution (change in size, shape, or color) is particularly relevant for the scalp. Since diameter is hard to measure, focusing on any noticeable change over time is important. Secondary symptoms, often mistaken for common scalp issues, can also be indicators.
Persistent itching, tenderness, or pain at the site of a mole should raise suspicion. Other warning signs include any spot that bleeds easily, scabs, or forms a non-healing sore. If these symptoms persist for several weeks, immediate medical evaluation is warranted, as they may indicate a rapidly growing, ulcerated lesion.
Medical Diagnosis and Staging
Once a suspicious lesion is identified, the diagnostic process begins with a clinical examination, often involving a dermatoscope. This specialized magnifying tool allows a clinician to examine the structures and patterns of the pigment below the skin’s surface. The definitive diagnosis is made through a biopsy, where tissue is removed and examined by a pathologist.
An excisional biopsy, which removes the entire lesion along with a small margin of healthy tissue, is preferred because it allows for the most accurate measurement of the tumor’s depth. The pathologist determines the Breslow depth, measured in millimeters from the skin surface to the deepest point of invasion. This measurement is the most important factor for determining prognosis and guiding treatment decisions.
Melanoma is formally staged by assessing the primary tumor, spread to nearby lymph nodes, and metastasis to distant organs. Ulceration (a breakdown of the skin over the tumor) is an adverse factor that raises the staging level. Given the aggressive nature of scalp melanoma, imaging studies like CT, MRI, or PET scans are frequently used to check for spread to regional lymph nodes or distant sites.
Treatment Approaches
The management of scalp melanoma is multi-modal, involving a combination of strategies tailored to the disease stage. The initial intervention for a localized tumor is surgical, performed as a Wide Local Excision (WLE). This procedure removes the melanoma along with a defined margin of healthy tissue, ensuring all cancerous cells are cleared based on the measured Breslow depth.
Because the scalp has limited loose skin, the resulting surgical defect is often large and requires immediate reconstruction. This frequently involves complex procedures using skin grafts or local tissue flaps to cover the area. For thicker melanomas, a Sentinel Lymph Node Biopsy (SLNB) is performed to determine if microscopic cancer cells have reached the first draining lymph node.
If the SLNB is positive, further treatment is recommended to reduce the risk of recurrence. This often includes adjuvant therapy, which is systemic treatment given after surgery. Immunotherapy agents, such as checkpoint inhibitors, harness the body’s immune system to recognize and attack cancer cells.
If the melanoma harbors specific genetic alterations, such as a BRAF gene mutation, targeted therapy drugs can be used. These medications block the proteins cancer cells rely on for growth, offering a precision approach. These advanced therapies are reserved for higher-risk or advanced-stage disease.