Cytogenetic, fluorescence in situ hybridization, and immunohistochemistry studies in a malignant pleural solitary fibrous tumor.

Pleural solitary fibrous tumor is a normally benign fibroblastic neoplasm; its recurrences and metastasis are associated with clinical and morphological characteristics of variable interpretation and efficacy of surgical treatment. Immunohistochemistry techniques have contributed decisively to the correct diagnosis of the lesion and define its prognosis. In the present case, cytogenetic and fluorescence in situ hybridization analyses revealed multiple chromosomal aberrations, including a del(9)(q21qter) and a marker chromosome ish der(9)(ABL+). The present data support but do not resolve the possible involvement of a gene on 9q22 in the biological behavior of these tumors, and the ABL rearrangements and deletions of 1p and 10p suggest another possible malignant component.