Skin cancer can affect the scalp, a location often overlooked during routine self-examinations. It is the uncontrolled growth of abnormal cells originating in the skin’s outer layer, the epidermis, typically caused by unrepaired DNA damage. The scalp is a common site for these lesions due to frequent sun exposure, but hair coverage often hides them. This combination of high risk and low visibility presents challenges for early detection compared to other areas of the body.
Understanding Scalp Vulnerability
The scalp is vulnerable to ultraviolet (UV) radiation because the sun’s rays hit it at a near-perpendicular angle. This intense exposure causes cumulative damage to skin cells over a person’s lifetime. While a full head of hair offers some natural protection, areas with thinning hair, bald spots, or a part line are exposed without a shield.
Men are often at higher risk than women, attributed to shorter hairstyles and a greater incidence of pattern baldness (androgenetic alopecia), which leaves the crown exposed. The difficulty of self-examination also contributes to delayed discovery, as the area is hard to see and feel. Scalp cancers are often diagnosed at a more advanced stage than those found on visible skin surfaces.
Risk factors include a history of blistering sunburns during childhood and having fair skin or light-colored hair, which contain less protective melanin. The rich network of blood and lymphatic vessels in the head and neck region means that established cancers may have a higher potential for aggressive behavior and spread.
Identifying Common Types and Warning Signs
The three most common types of skin cancer—Basal Cell Carcinoma (BCC), Squamous Cell Carcinoma (SCC), and Melanoma—can all appear on the scalp. BCC, the most frequent type, often presents as a shiny, translucent, or pearly bump that may be pink or flesh-colored. It may also look like a persistent, non-healing sore that bleeds easily.
Squamous cell carcinoma (SCC) is the second most common and typically appears as a rough, scaly patch or a crusty growth. This type may also manifest as an open sore that does not resolve or returns, and it can become tender. Both BCC and SCC are grouped as non-melanoma skin cancers and are highly treatable when caught early.
Melanoma, though less common, is the most dangerous form due to its potential to spread rapidly. On the scalp, it may be hidden beneath the hair, often leading to delayed diagnosis and worse outcomes. Signs often align with the ABCDE rule:
- Asymmetry
- Border irregularity
- Color variation (multiple shades of brown, black, or red)
- Diameter larger than a pencil eraser
- Evolving or changing size and shape
Any new mole, dark spot, or existing lesion on the scalp that changes, bleeds, or looks different should be brought to a doctor’s attention immediately.
The Process of Diagnosis and Removal
Once a suspicious spot is identified, consultation with a dermatologist is necessary. They perform a visual examination, often using a specialized magnified tool called a dermatoscope. If the lesion is concerning, a biopsy is performed for a definitive diagnosis. This procedure involves removing a small tissue sample, via a shave or punch technique, to be analyzed under a microscope for cancer cells.
If cancer is confirmed, the primary treatment for most non-melanoma skin cancers on the scalp is surgical removal. Mohs micrographic surgery is a preferred method for the head and neck area because it allows for the precise, layer-by-layer removal of cancerous tissue while preserving healthy tissue. The surgeon examines the tissue edges immediately to ensure all cancer cells are removed, achieving high cure rates for BCC and SCC.
For larger or aggressive cancers, a wider surgical excision may be necessary. In cases of melanoma, further evaluation, such as a sentinel lymph node biopsy, may be required to check for spread. The prognosis for scalp skin cancer is directly linked to the timing of its discovery, emphasizing that prompt professional evaluation ensures the most successful outcome.