Abstract
In the last decade, new tumor entities have been described, including
-rearranged neoplasms of different biologic behavior. To gain further insights into the behavior of these tumors, we analyzed a spectrum of
-rearranged neoplasms and discuss their key diagnostic and molecular features in relation to their prognosis. We report five patients with
-rearranged neoplasms, including one simple bone cyst (SBC), two complex cystic bone lesions lacking morphological characteristics of SBC, and two sarcomas. In three cases, fluorescence in situ hybridization (FISH) and in all cases copy number variation (CNV) profiling and fusion analyses were performed. All patients were male, three cystic lesions occurred in children (aged 10, 14, and 17 years), and two sarcomas in adults (69 and 39 years). Fusion analysis revealed two
rearrangements in two cystic lesions and three
rearrangements in one complex cystic lesion and two sarcomas.
FISH revealed tumor cells with break-apart signal without amplification in one complex cystic lesion and
amplification in both sarcomas was documented. CNV analysis showed simple karyotypes in all cystic lesions, while more complex karyotypes were found in
-rearranged sarcomas. Our study supports and expands previously reported molecular findings of
-rearranged neoplasms. The study highlights the importance of combining radiology and morphologic features with molecular aberrations. The use of additional molecular methods, such as CNV and FISH in the routine diagnostic workup, can be crucial in providing a correct diagnosis and avoiding overtreatment.
