A Study On ALK Fusion Gene And Nasopharyngeal Carcinoma

[Objective] To study the rearrangement of the anaplastic lymphoma kinase(ALK) gene and the expression of ALK in nasopharyngeal carcinoma(NPC),and to investigate the correlation between ALK gene rearrangement and NPC.[Methods] Ninety-nine cases of NPC biopsies of northern Chinese patients, from2006to2009, were collected from the Department of Pathology, Cancer Hospital of Chinese Academy of Medical Science. All cases were formalin-fixed and paraffin-embedded. A recently developed ALK(D3F5) monoclonal antibody was used to assess ALK fusion protein expression using immunohistochemistry (IHC). Fluorescence in situ hybridization(FISH) was also performed on the neoplastic cells to detect ALK gene abnormality.[Results] ALK fusion protein expression was found in1of99cases(1.0%).In this case, ALK was expressed in cytoplasm. A sample is considered positive if≥15%tumor cells shows splitting signals in FISH analysis. According to this criteria, the detection rate of ALK gene rearrangement is1.0%(1/99) in NPC. The result of FISH is concordant to IHC.[Conclusion] ALK gene rearrangement and protein expression shows a extremely low incidence rate in NPC. Whether ALK fusion gene is related to NPC remains uncertain.