ALK-rearranged cutaneous spindle cell tumors with co-expression of CD34 and S100 in 2 cases and literature review
AN Jin
LI Li
Abstract：Objective Two cases of anaplastic lymphoma kinase(ALK)-rearranged cutaneous spindle cell tumors with unique morphologic features and co-expression of S100 and CD34 are reported to improve clinicians'understanding of this type of soft tissue spindle cell tumors.Methods Two cases receiving consultation of doctors from other hospitals were collected.The expressions of vimentin,ALK(D5F3),BCL2,CD34 and Ki-67 in tumors were detected by using EnVision immunohistochemical two-step method.ALK gene rearrangement was detected by using break-apart fluores-cence in situ hybridization(FISH)probes in 1 case and by using next-generation sequencing(NGS)in the other case.Results Morphologically,the tumor cells were composed of mild spindle cells or ovoid cells arranged in bundle-like or whirlpool-like pattern,with interstitial hyaline degeneration and mucinous degeneration and visible more open vascular lumens.These tumors expressed both CD34 and S100,and ALK gene rearrangements were found.Conclusion The ALK-rearranged cutaneous spindle cell tumors with co-expression of CD34 and S100 in the 2 cases have unique morphology,identical immunohistochemical expression and molecular characteristics,and similar clinicopathological features to neu-rotrophic tyrosine receptor kinase(NTRK)-rearranged spindle cell tumors.
Keywords：ALK rearrangementCD34 and S100 co-expressionCutaneous spindle cell tumor
Publication Date：2024-07-28
Online Publishing Date：2025-08-15(First online date of this platform, not the publication date of the document)
Pages：4( 745-748 )