The scalp is frequently exposed to ultraviolet (UV) radiation, making it a high-risk location for developing skin cancer. It is susceptible to common non-melanoma skin cancers, such as Basal Cell Carcinoma (BCC) and Squamous Cell Carcinoma (SCC), as well as the more dangerous Melanoma. Recognizing abnormal lesions on the scalp is complicated, but early detection is essential for successful treatment. Understanding the visual signs of these cancers is the first step toward vigilance.
Why Skin Cancer on the Scalp is Often Overlooked
The anatomy of the scalp creates unique obstacles to the early discovery of cancerous lesions. Hair coverage naturally obscures visibility, preventing individuals from easily spotting new or changing spots during routine self-examination. The scalp is difficult to inspect without the aid of mirrors or a partner.
This challenge often means that skin cancers on the scalp are not diagnosed until they are more advanced. Lesions are frequently mistaken for benign irritations, such as persistent dandruff, a stubborn scab, or a bug bite that will not heal. The initial discovery often falls to a professional, such as a hairdresser or barber, who is trained to examine the scalp.
Visual Signs of Basal Cell and Squamous Cell Carcinoma
Basal Cell Carcinoma (BCC) is the most frequently occurring type of skin cancer and often appears on the scalp as a small, raised lesion. BCCs may present as a pearly or waxy bump that is translucent, sometimes with tiny visible blood vessels on the surface. On the scalp, they commonly look like a non-healing sore that repeatedly bleeds, scabs over, and then reappears over several weeks.
Another presentation of BCC is a flat, scar-like patch, known as morpheaform BCC, which may appear white or yellowish and have poorly defined borders. These lesions often feel firm and can be mistaken for a healed injury. BCCs typically grow slowly and rarely spread, but they can cause significant damage to the surrounding tissue if left unaddressed.
Squamous Cell Carcinoma (SCC) is the second most common form and tends to be more aggressive than BCC, with a higher risk of spreading. SCCs frequently develop from actinic keratoses, which are rough, scaly, pre-cancerous patches. On the scalp, SCCs may appear as a firm, red nodule that can grow rapidly.
SCC can also manifest as a persistent, thick, scaly, or crusted patch of skin that may be tender or bleed easily when bumped. Unlike a temporary scab, an SCC lesion often has a rough, warty surface and may have an open sore in the center. SCC is more likely to appear as a continuously growing, persistent sore or a rough, elevated patch.
Identifying Melanoma on the Scalp
Melanoma is the most serious form of skin cancer and is particularly dangerous when it develops on the scalp. It may go unnoticed until it reaches a late stage. Because the scalp is rich in blood vessels and lymphatic drainage, a delayed diagnosis may allow the cancer to spread more quickly. Melanoma is identified using the specialized ABCDE criteria, which focuses on changes in pigmented spots or moles.
The criteria begin with Asymmetry, where one half of the spot does not match the other half, and Border irregularity, meaning the edges are ragged, notched, or blurred. Color variation is a major sign, with the lesion exhibiting multiple shades of black, brown, tan, red, white, or blue within the same spot. The Diameter of a concerning lesion is typically greater than six millimeters, roughly the size of a pencil eraser, though melanomas can be smaller when first detected.
The most important criterion is Evolving, meaning the mole is changing in size, shape, color, or elevation, or begins to display new symptoms like itching or bleeding. A particularly challenging form is amelanotic melanoma, which lacks the typical dark pigment. It may appear as a pinkish or reddish patch, a lump, or a skin-colored lesion, making the ABCDE rule harder to apply.
When to Seek Professional Evaluation
Any new or changing spot on the scalp that raises suspicion warrants an immediate visit to a dermatologist. A persistent sore that fails to heal after two to three weeks, or a lump that bleeds easily, should be evaluated without delay. Lesions that change rapidly in size, shape, or color, or those that feel noticeably different from other spots, are strong indicators for a professional check.
To perform an effective self-check, a hand mirror and a comb can be used to systematically part the hair and examine the entire scalp. Individuals with thinning hair or a family history of skin cancer should be vigilant during these monthly examinations. If a suspicious spot is found, the dermatologist will typically use a specialized magnifying tool called a dermatoscope to examine the lesion.
If the lesion remains suspicious after visual inspection, the physician will perform a biopsy. This involves removing a small tissue sample for laboratory analysis. This procedure is the only definitive way to confirm a cancer diagnosis and determine the specific type of skin cancer present. Early action following the discovery of an unusual lesion drastically improves the likelihood of a successful outcome.