A spitzoid tumor is an uncommon type of skin lesion. These growths are a form of mole with a distinct microscopic appearance, most often identified in children and young adults. About 70 percent of cases develop in individuals under the age of 20. They can appear as a rapidly growing pink or red bump, and their classification can vary significantly. Understanding the nature of a specific spitzoid lesion requires a detailed pathological examination after it is removed.
The Spitzoid Spectrum
Spitzoid lesions exist on a spectrum from harmless to cancerous, divided into three main categories. A pathologist determines the classification by examining the microscopic features of the cells within the lesion, such as their size, shape, and growth pattern. This analysis helps determine the appropriate course of action.
The Spitz nevus is a benign (non-cancerous) mole and the most common type of spitzoid lesion, particularly in younger individuals. Microscopically, the cells are uniform and well-organized. They tend to “mature” as they go deeper into the skin, meaning the cells become smaller, which is a sign of benign behavior. Although a Spitz nevus can grow quickly at first, it is considered harmless.
The atypical Spitz tumor (AST) is an intermediate category for lesions with some features of a benign Spitz nevus but also other unusual characteristics. A pathologist might identify variations in cell size and shape or see cells dividing more frequently than expected. Because their features are not clearly benign or malignant, the future behavior of these tumors can be uncertain, though most do not cause further problems.
Spitzoid melanoma is the malignant form of a spitzoid tumor and a subtype of skin cancer. These lesions show significant microscopic irregularities (atypia). The cells lack symmetry, may invade deeper into the skin without maturing, and can have an increased number of atypical cell divisions. Spitzoid melanomas are cancerous and can spread, but they are rare, especially in children.
Identifying and Diagnosing Spitzoid Lesions
Identification often begins with noticing a new or changing spot on the skin. These lesions appear as a solitary, dome-shaped papule or nodule with color ranging from pink or red to brown or black. They often grow rapidly over a few months, which prompts a visit to a dermatologist. The most common locations are the head and neck in children and the lower legs in adults.
A dermatologist will assess the lesion’s characteristics during a clinical examination. They may use a dermatoscope, a handheld magnifying device, to view the mole’s pigment patterns and blood vessel structures. While certain patterns can suggest a spitzoid lesion, this examination alone cannot confirm the diagnosis.
A skin biopsy is the definitive diagnostic step. The procedure involves surgically removing the entire lesion, a process called an excisional biopsy, and sending it to a laboratory. A pathologist, a doctor who specializes in diagnosing diseases by examining tissue, then analyzes the lesion’s microscopic architecture and cellular details.
Distinguishing between the types of spitzoid lesions can be challenging because the microscopic features can be subtle and overlapping. In ambiguous cases, advanced molecular or genetic tests can aid the diagnosis. These tests detect specific genetic alterations, such as gene fusions or chromosome changes, that are more common in either benign or malignant spitzoid tumors.
Treatment Approaches
The standard treatment for any lesion on the spitzoid spectrum is complete surgical removal. This approach is taken regardless of the specific diagnosis, from a benign Spitz nevus to a spitzoid melanoma. The primary goal is to ensure the entire lesion is removed from the skin, which is often curative for benign and many atypical lesions.
Achieving “clear surgical margins” is a primary goal of the surgery. This means the surgeon removes the visible tumor and a small rim of the surrounding normal-appearing skin. A pathologist then examines the removed tissue to confirm the margins are free of tumor cells, which reduces the risk of recurrence.
The width of the surgical margins varies depending on the final diagnosis. For a benign Spitz nevus, a narrow margin of a few millimeters is sufficient. Atypical Spitz tumors or spitzoid melanomas require a wider margin of normal skin, with the specific width determined by the pathologist’s findings and clinical guidelines.
Follow-Up Care and Monitoring
After a spitzoid lesion is surgically removed, the follow-up care plan is based on the final pathology report. This phase focuses on monitoring for any signs of recurrence and detecting any new, concerning skin lesions.
For a patient with a benign Spitz nevus, complete excision is considered the cure, and no further treatment is necessary. A dermatologist may still recommend periodic skin checks as a general precaution, especially for those with many moles or a family history of skin cancer.
Cases of an atypical Spitz tumor or a spitzoid melanoma require more diligent follow-up. Patients are scheduled for regular, full-body skin examinations with a dermatologist. These appointments allow the doctor to monitor the excision site and check the entire skin surface for new or evolving moles.
Patient education on performing monthly self-skin checks is a component of long-term care. The dermatologist instructs the patient on what to look for, such as new growths or changes in existing moles. Regularly examining their own skin allows patients to bring any suspicious findings to their doctor’s attention promptly.