Cellular neurothekeoma is a rare and benign skin tumor. Despite its name, which might suggest a connection to nerve sheaths, its exact cellular origin is still under investigation, with current understanding pointing towards a fibrohistiocytic derivation rather than a nerve sheath one.
Understanding Cellular Neurothekeoma
Cellular neurothekeoma typically appears as a small, firm nodule on the skin, often ranging from 0.5 to 2 centimeters in diameter. It can be skin-colored, pink, reddish-brown, or brown. While usually painless, some individuals may experience pain when pressure is applied to the lesion.
These tumors commonly arise on the head, neck, and upper extremities, including the shoulder. They are observed across all age groups, but are most frequently diagnosed in young adults. There is a tendency for cellular neurothekeoma to affect females more often than males.
Diagnosing Cellular Neurothekeoma
Identifying cellular neurothekeoma based solely on its appearance can be challenging because it resembles several other skin lesions. Therefore, a clinical examination by itself is often not enough for a definitive diagnosis. To confirm the presence of cellular neurothekeoma, a biopsy is necessary.
During a biopsy, a small tissue sample of the lesion is removed and then examined microscopically by a dermatopathologist. This helps differentiate cellular neurothekeoma from other conditions that might look similar, such as Spitz nevus, plexiform fibrohistiocytic tumor, or even certain melanomas. Pathologists look for specific features, including nests of epithelioid to spindled cells with pale cytoplasm, often separated by dense collagen, and a general lack of S100 protein reactivity, which helps distinguish it from true nerve sheath myxomas.
Treatment and Prognosis
The standard treatment for cellular neurothekeoma involves complete surgical excision. This procedure typically entails removing the entire lesion along with a small margin of surrounding healthy tissue. The aim is to prevent any remaining tumor cells from regrowing at the site.
Following complete surgical removal, the prognosis for cellular neurothekeoma is considered excellent. Recurrence after complete excision is uncommon. Even if some atypical features are observed in the tumor cells, such as increased nuclear variability or a higher mitotic rate, these characteristics do not generally impact the likelihood of recurrence following complete removal. While follow-up recommendations may vary, they generally focus on monitoring the site.