Neurothekeoma.

OBJECTIVES: The purpose of this study was to investigate and share the experiences at The University of Texas M. D. Anderson Cancer Center in diagnosing, treating, and following patients with neurothekeoma. We report 13 cases.

STUDY DESIGN: Case series. The clinical, surgical, and pathology records of the 7 patients with neurothekeoma treated at M. D. Anderson Cancer Center were retrospectively reviewed. In addition, the pathology records of 6 patients reviewed by the Department of Pathology for diagnosis only were retrospectively reviewed.

RESULTS: Nine patients were women. Their mean age was 30 years (median, 24 years). Six of the lesions were on the head or neck, 4 were on extremities, and 2 were on the trunk, and the location of 1 was not recorded. Two lesions had been previously diagnosed, histologically, as leiomyosarcomas, 1 as a malignant nodular hidradenoma, and 1 as a clear cell hidradenoma. All the lesions had the characteristic nested pattern of growth, with various degrees of myxoid background. Mitotic figures and marked cellular pleomorphism were not common. Six cases were treated with wide local excision. A lesion of the nasal ala was excised by using Mohs micrographic surgery. Most cases were limited to the dermis, but 2 lesions infiltrated subcutaneous tissue and skeletal muscle. All patients were without evidence of disease at 8 months median follow-up range (0 to 35 months).

CONCLUSION: Neurothekeoma is a benign neoplasm occurring usually in women and commonly in the head and neck. Because it may be locally invasive, treatment with wide local excision using frozen section control of margins is recommended. Care must be taken in the pathologic diagnosis of cutaneous neoplasms, and neurothekeoma should be considered in the differential diagnosis for spindle cell lesions.

SIGNIFICANCE: Neurothekeoma is commonly misdiagnosed, pathologically and clinically, and it can be treated successfully with surgical excision.

EBM RATING: C.