Cutaneous epithelioid malignant schwannoma: review of the literature and case report

Cutaneous Malignant Peripheral Nerve Sheath Tumor

Cutaneous malignant peripheral nerve sheath tumors (MPNSTs) are rare sarcomas of neuroectodermal origin arising in the dermis and/or subcutis. In contrast with their deep soft tissue and visceral counterparts, cutaneous MPNSTs are rarely associated with neurofibromatosis type 1. Two main subtypes of cutaneous MPNST can be distinguished histologically: conventional (ie, spindle cell) and epithelioid MPNST. The 2 subtypes also differ in predilection for deep versus superficial locations, association with preexistent benign peripheral nerve sheath tumors and S100 immunohistochemistry. Herein, we review current knowledge of cutaneous MPNST and discuss its differential diagnosis.

Cutaneous epithelioid malignant peripheral nerve sheath tumour: a clinicopathological analysis of 11 cases

AIMS

Epithelioid malignant peripheral nerve sheath tumour (E-MPNST) is a distinctive variant of malignant peripheral nerve sheath tumour characterized by the predominance of epithelioid cells, diffuse S100 positivity and infrequent association with neurofibromatosis type 1. The aim of this study was to further delineate clinicopathological features of cutaneous E-MPNST, correlate them with disease outcome and discuss differential diagnosis.

METHODS AND RESULTS

We analysed 11 cutaneous E-MPNSTs (six males, five females, median age 49 years, median size 1.6 cm). Tumours showed a predilection for lower extremities (45%) and trunk (45%), followed by upper extremity (9%). Follow-up was available for nine of 11 patients (range 24-100 months, median 52 months). Four patients had an uneventful clinical course (44%), two developed local recurrence(s) (22%) and three died due to disseminated disease (33%). No histological parameters were found to predict local recurrence(s), development of distant metastases or disease outcome, including size, percentage of epithelioid component, number of mitoses per 10 high-power fields, degree of nuclear atypia or site of occurrence (dermis, dermis/subcutis, subcutis) (P > 0.05). Immunohistochemically, all tumours were diffusely S100-positive, with a subset displaying loss of integrase interactor 1 (INI1) expression (50%).

CONCLUSIONS

Cutaneous E-MPNST has the potential to pursue an aggressive clinical course, associated with wide dissemination and unfavourable disease outcome.

Dermatofibrosarcoma protuberans in an adolescent: a case report and review of the literature

Classically, dermatofibrosarcoma protuberans (DFSP) is a disease of adults. The world literature revision shows that several pediatric cases have been reported so far; this might suggest that the number of infants with the condition might be larger than that estimated previously. Here, we report the 183rd case of histologically confirmed DFSP in young age. A 14-year-old white male patient came under our care for a slowly growing, pale brownish lesion on the neck skin. A biopsy specimen showed a DFSP. Subsequently, a wide surgery excision with 3 cm of resection margins including the underlying fascia was performed. To date, the patient has been in follow-up for 6 years without evidence of recurrent disease. The clinical features and treatment of DFSP diagnosed in childhood and adolescence reported in the published literature are reviewed to provide new insights about this rare entity. The aim is to emphasize the importance of biopsy for histologic evaluation in the cases that show a persistent or a large cutaneous plaque or nodule without pathognomonic clinical features that permit a clinical diagnosis. An accurate knowledge of the disease is the prerequisite for a wider recognition and appropriate treatment.

Advanced epithelioid malignant peripheral nerve sheath tumor showing complete response to combined surgery and chemotherapy: a case report

Malignant peripheral nerve sheath tumor (MPNST) is a rare high-grade soft tissue sarcoma. The epithelioid variant accounts for 5% or less of MPNSTs; the clinical behavior of this variant is unclear. Reports of approximately 40 cases are available in the English literature; however, most reports addressed clinicopathological features rather than therapeutic procedures or clinical courses. We describe a case of a 62-year-old male with an epithelioid MPNST of the left foot. Multiple lung metastases developed after radical surgery on the primary lesion. The response to adjuvant chemotherapy including doxorubicin and ifosfamide was favorable, and thoracoscopic resection was subsequently performed on the remaining three metastases. No evidence of recurrence or metastasis was observed at the 12-month followup after the first operation. Further followup and chemotherapy may be required.