Premium
Cutaneous Solitary Fibrous Tumor of Uncertain Malignant Potential
Author(s) -
Shapiro B.,
Cotton J.,
Billings S.
Publication year - 2005
Publication title -
journal of cutaneous pathology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.597
H-Index - 75
eISSN - 1600-0560
pISSN - 0303-6987
DOI - 10.1111/j.0303-6987.2005.320az.x
Subject(s) - solitary fibrous tumor , pathology , cd34 , hemangiopericytoma , soft tissue , immunophenotyping , medicine , scalp , immunohistochemistry , differential diagnosis , lung , anatomy , biology , stem cell , flow cytometry , genetics , immunology
Solitary fibrous tumor (SFT) is an uncommon mesenchymal neoplasm that typically arises in the pleural cavity but may also be seen at extra‐pleural sites including liver, lung, thymus, orbit, soft tissue, and rarely the skin. The diagnosis of cutaneous SFT is challenging due to its histologic variability and lack of distinctive immunophenotype. We report a case of SFT with unusual histologic and immunophenotypic findings. A 23‐year‐old man presented with a two‐year history of a painful, enlarging scalp mass. Histologic examination revealed a variably cellular neoplasm composed of tumor cells with uniform oval nuclei embedded in a collagenous matrix. In areas there was a prominent hemangiopericytoma‐like vasculature. The tumor was strongly immunoreactive for CD34 and had some immunoreactivity for S100. The diagnosis of SFT was rendered based upon the histologic features and strong immunoreactivity for CD34. Immunoreactivity for S100 is rarely seen in SFT. The tumor had a mitotic rate of 8/50 hpf. Mitotic rates greater than 5/50 hpf have been associated with aggressive behavior in SFTs of soft tissue. The significance of aggressive histologic attributes with clinical outcome is yet to be determined in cutaneous SFT. Cutaneous SFTs should be considered in the differential diagnosis of superficial spindle cell tumors.