Yann Charli-Joseph1, Andrea Saggini1, Leona A Doyle2, Christopher D Fletcher2, Jingly Weier3, Sonia Mirza3, Swapna Vemula3, Philip E LeBoit4. 1. Pathology Department, University of California, San Francisco, California; Dermatology Department, University of California, San Francisco, California. 2. Pathology Department, Brigham and Women's Hospital, Boston, Massachusetts. 3. Pathology Department, University of California, San Francisco, California. 4. Pathology Department, University of California, San Francisco, California; Dermatology Department, University of California, San Francisco, California; Helen A. Diller Family Comprehensive Cancer Center, University of California, San Francisco, California. Electronic address: philip.leboit@ucsf.edu.
Abstract
BACKGROUND: Cutaneous fibrous histiocytoma (FH) is a common mesenchymal neoplasm. Metastasis is rare, disproportionately occurring among the aneurysmal, cellular, atypical, and deep variants. OBJECTIVE: We determined whether DNA copy number changes occurred in atypical FH (AFH), and whether they were similar to those in metastasizing FH (MetFH) and benign cellular FH (CFH). METHODS: Five primary tumors of MetFH were evaluated by array-based comparative genomic hybridization analysis, with tissue from local recurrences and lung metastases in 2 and 2 patients, respectively. Seven indolent AFH and 5 CFH were identified for comparison. RESULTS: Substantial differences between the groups were found both in the frequency of chromosomal aberrations (higher among MetFH and absent or solitary in CFH) and array-based comparative genomic hybridization profiles (frequent gains of 7 and 8q and losses of Xq in MetFH; recurrent losses of chromosomes 9 and 22 in AFH; isolated loss of 5q and gain in chromosome 20 in 2 CFH). Fatal MetFH cases (2 of 5 cases) exhibited the highest rate of chromosomal aberrations. LIMITATIONS: This study included a small sample size with a short-term follow-up. CONCLUSIONS: Benign CFH, indolent AFH, and MetFH represent distinct biological entities within the spectrum of FH; array-based comparative genomic hybridization may be a tool in recognizing FH cases with metastatic potential and increasingly aggressive behavior.
BACKGROUND:Cutaneous fibrous histiocytoma (FH) is a common mesenchymal neoplasm. Metastasis is rare, disproportionately occurring among the aneurysmal, cellular, atypical, and deep variants. OBJECTIVE: We determined whether DNA copy number changes occurred in atypical FH (AFH), and whether they were similar to those in metastasizing FH (MetFH) and benign cellular FH (CFH). METHODS: Five primary tumors of MetFH were evaluated by array-based comparative genomic hybridization analysis, with tissue from local recurrences and lung metastases in 2 and 2 patients, respectively. Seven indolent AFH and 5 CFH were identified for comparison. RESULTS: Substantial differences between the groups were found both in the frequency of chromosomal aberrations (higher among MetFH and absent or solitary in CFH) and array-based comparative genomic hybridization profiles (frequent gains of 7 and 8q and losses of Xq in MetFH; recurrent losses of chromosomes 9 and 22 in AFH; isolated loss of 5q and gain in chromosome 20 in 2 CFH). Fatal MetFH cases (2 of 5 cases) exhibited the highest rate of chromosomal aberrations. LIMITATIONS: This study included a small sample size with a short-term follow-up. CONCLUSIONS: Benign CFH, indolent AFH, and MetFH represent distinct biological entities within the spectrum of FH; array-based comparative genomic hybridization may be a tool in recognizing FH cases with metastatic potential and increasingly aggressive behavior.