Erickson-Johnson suggested that USP6 transcriptional upregulation may be the driving force behind the high proliferative activity and growth and the consistent involution nature of Nodular Fasciitis (NF). The author previously reported the case series of NF and strongly suggested that proliferative findings of the margin of the nodule on US and pathological features are caused by the driving force of USP6 transcriptional upregulation from an established cytogenetic nature. Recently molecular analysis of USP6 gene rearrangements have been detected in the most of NF cases, while MYH9 gene has been identified as the most common USP6 partner. It is suggested that the identification of USP6 fusion partners for NF may contribute to understand the biological effect. As intradermal NF is a rare lesion, few cases with molecular genetics have been shown until now. This review outlines the current knowledge and trends of the rare intradermal nodular fasciitis focusing on the genetic analysis. The result showed USP6 rearrangement in all cases and two cases of MYH9, one case of EIF5A, and one case of TPM4 as a fusion partner with USP6 have been exhibited. The detection of USP6 gene rearrangement using FISH may be the very useful and important genetic analysis for accurate diagnosis in even intradermal NF. Further study is needed to verify the pathogenesis of development and biological effect of fusion partner for this entity.
Published Date: 2024-09-27; Received Date: 2024-08-27