Muscarella Lucia Anna, Rossi Giulio, Trombetta Domenico, La Torre Annamaria, Di Candia Leonarda, Mengoli Maria Cecilia, Sparaneo Angelo, Fazio Vito Michele, Graziano Paolo
Laboratory of Oncology, Scientific Institute for Research and Healthcare, Casa Sollievo della Sofferenza, I-71013 San Giovanni Rotondo, Italy.
Pathologic Anatomy Unit, University Hospital Policlinico, I-41124 Modena, Italy.
Oncol Lett. 2017 Feb;13(2):593-598. doi: 10.3892/ol.2016.5504. Epub 2016 Dec 14.
Inflammatory myofibroblastic tumors (IMT) in the head and neck region are rare neoplasms that generally mimic benign/low-grade neoplasms. Overexpression of anaplastic lymphoma kinase () has been reported in 50% of IMT cases, secondary to activation by structural rearrangements in the gene, which results in a fusion protein with echinoderm microtubule associated protein like 4 () in ~20% of cases. The present study describes a case of a 74-year-old woman with a malignant IMT in the right posterior hypopharynx harboring a previously unreported chromosomal rearrangement resulting in and gene fusion. Strong ALK immunoreactivity was observed in neoplastic cells, while fluorescent hybridization combined with fluorescent fragment analysis and direct sequencing identified the first case of the 3a/b variants of the fusion gene in IMT. The results of the current study highlight the uncommon occurrence of ALK-positive IMT in the head/neck region and demonstrate the importance of integrating different molecular methodologies to identify unequivocal gene fusion characterization.
头颈部炎性肌纤维母细胞瘤（IMT）是一种罕见肿瘤，通常类似良性/低级别肿瘤。据报道，50%的IMT病例中存在间变性淋巴瘤激酶（ALK）过表达，这是由于ALK基因发生结构重排激活所致，约20%的病例会产生一种与棘皮动物微管相关蛋白样4（EML4）的融合蛋白。本研究描述了一例74岁女性患者，其右下咽恶性IMT存在一种此前未报道的染色体重排，导致ALK和EML4基因融合。在肿瘤细胞中观察到强烈的ALK免疫反应性，而荧光原位杂交结合荧光片段分析和直接测序确定了IMT中首例ALK-EML4融合基因的3a/b变体。本研究结果突出了头颈部ALK阳性IMT的罕见性，并证明了整合不同分子方法以明确基因融合特征的重要性。
