CHD4 as a Potential Biomarker in Differentiating Between Cellular Schwannoma and Malignant Peripheral Nerve Sheath Tumor
Cellular schwannoma is an uncommon variant of benign peripheral nerve sheath tumors, but is commonly misdiagnosed as malignant peripheral sheath tumor (MPNST). Conventional methods that are used to distinguish cellular schwannoma from MPNST include immunohistochemistry (IHC) staining. However, most markers cannot precisely differentiate these 2 tumor types, and thus identification of a better marker is needed to improve the accuracy of diagnosis. Here, we evaluate the use of chromodomain helicase DNA-binding protein 4 (CHD4) as a specific marker for cellular schwannoma by comparing CHD4 and S-100 IHC staining in 14 cellular schwannoma and 17 MPNST tissue samples. Our results indicated that nuclear CHD4 stains were in moderate-to-high in 94% MPNST (16 cases) and 93% cellular schwannoma (13 cases). However, cytoplasmic CHD4 stains were moderate-to-high in 93% cellular schwannoma (13 cases) but negative-to-weak in 100% MPNST (17 cases). In contrast, the S-100 stains were moderate-to-high in 86% of the cellular schwannoma (12 cases) and in 35% of the MPNST (6 cases). Taken together, the results indicated that different location of CHD4 staining is a potential biomarker to differentiate cellular schwannoma from MPNST.