Primary Clear Cell Sarcoma of the Dermis Mimicking Malignant Melanoma

Abstract

Background:Clear cell sarcoma is a rare malignant soft tissue neoplasm that typically involves tendons and aponeurosis. Clear cell sarcoma in the dermis is an extremely rare occurrence, and it is difficult to differentiate between this neoplasm and dermal malignant melanoma because they have similar morphologic and immunohistochemical features. Although rare, clear cell sarcoma of the skin typically occurs in the extremities. To our knowledge, there are no reported cases of primary clear cell sarcoma of the skin occurring in the neck. Here, we report an unusual case of clear cell sarcoma arising in the skin of the neck.Case Report:A 43-year-old female presented with a right neck lesion. Histologic sections of the lesion showed a nodular proliferation of spindle cells with pale cytoplasm with epithelioid features involving the entire dermis with no epidermal component. The tumour cells were positive for melanocytic markers, including S100 and Human Melanoma Black 45, which led to an initial diagnosis of malignant melanoma. Fluorescence in situ hybridization showed a rearrangement of the EWSR1 gene on chromosome 22q12, which led to a diagnosis of primary clear cell sarcoma in the skin.Conclusion:Because the treatments for clear cell sarcoma and conventional melanoma are different, fluorescence in situ hybridization for EWSR1 should be performed in any dermal lesions with melanocytic features that do not have an in situ component.

Clear cell sarcoma of soft tissue with eccrine differentiation: A case report and review of the literature

“…While reported cases have a wide age range, most cases occur within ages 20 to 40 2 . They make up only 1% of all soft tissue sarcomas 3,4 . The prognosis is usually poor with some studies citing a 63% survival rate at 5 years and 36% at 10 years 5,6 .…”

Primary clear cell sarcoma in the lung apex with spinal metastasis: a fatal outcome

“…CCS is a rare tumour with a propensity to arise in the distal extremities such as the foot and ankle, as well as rarer locations such as bone, dermis and tongue 3 5–7. Prognosis is poor, with a reported 5-year survival rate of 50% and a 10-year survival rate of 38% 3.…”

Clear cell sarcoma in unusual sites mimicking metastatic melanoma

“…The patient is currently stable with an estimated 5-year survival of about 70% based on prior studies[22]. We recently reported a case of clear cell sarcoma of the dermis that was completely excised and the patient is currently disease free two years post resection[23]. Based on our limited experience and published literature, it appears that early detection and tumor resection is the key to good clinical outcome[22,23].…”

“…We recently reported a case of clear cell sarcoma of the dermis that was completely excised and the patient is currently disease free two years post resection[23]. Based on our limited experience and published literature, it appears that early detection and tumor resection is the key to good clinical outcome[22,23]. Due to the rarity of the entity in the submandibular gland and thoracic spine, it is not possible at present to predict the outcome of treatment in the afflicted patients.…”