Ultrastructural analysis shows tumor cells closely apposed to each other by continuous basal laminae and rudimentary cell junctions. Cells show abundant cytoplasm containing numerous mitochondria and aggregates of glycogen.
The differential diagnosis includes synovial sarcoma, fibrosarcoma, epithelioid forms of malignant peripheral nerve sheath tumor, spindle cell melanoma. One of the main differential diagnoses of CCS is malignant melanoma (MM). CCS and MM demonstrate significant morphologic overlap at light microscopic and ultrastructural levels, as well as similar immunohistochemical features, so the distinction may be difficult. However, the behavior of CCS is decidedly different from that of MM, demonstrating a more indolent course. CCS is a deep seated tumor that rarely shows the degree of anaplasia, necrosis, and mitotic activity usually associated with MM. Morever the t(12 ; 22) translocation and EWSR1/ATF1 gene rearrangement observed in the majority of cases of CCS have never been found in MM. Approximately 50% of MMs showed deletions of short arm of chromosome 9 at the interferon alfa locus. viagra plus
Treatment should be radical resection of the tumor, followed by chemotherapy and radiotherapy. However chemotherapy and radiotherapy have not been shown to be of benefit, so early recognition of this disease and prompt wide excision of tumor is essential for a favorable outcome. The prognosis for patients with CCS is generally poor, although those with tumors smaller than 2 cm have a better prognosis. Poor prognosis is associated with tumor size more than 5 cm, presence of necrosis, metastasis and local recurrence.
We encountered a rare case of CCS arising in the abdomen. Although CCS is usually fatal after a long clinical course, our patient is still alive without recurrence 14 months after resection.