Immunohistochemistry or Molecular Analysis: Which Method Is Better for Subtyping Craniopharyngioma?

In this study, we investigated whether immunohistochemistry could replace genetic analysis as an aid in subtype diagnosis. Here, 38 CP patients who had undergone their first tumor resection were included. Among the 38 cases, 22 were morphologically diagnosed as ACP, 10 cases were diagnosed as PCP, and six cases were diagnosed as undetermined CP that were morphologically difficult to classify as either ACP or PCP. Results of immunohistochemistry and genetic analysis and clinical features were compared. Based on the immunohistochemistry, 26 (22 ACPs and four undetermined CPs) showed nuclear β-catenin expression, 11 (nine PCPs and two undetermined CPs) exhibited positive BRAF V600E immunostaining, and one PCP showed membranous β-catenin expression and negative BRAF V600E immunostaining. Among the 26 nuclear β-catenin expression cases, 11 hadCTNNB1 mutations; however, 15 cases had mutations of neitherCTNNB1 norBRAF V600E. All 11 BRAF V600E immunopositive cases hadBRAF V600E mutations. When comparing clinical features, pediatric patients and those with tumor calcification and less solid components on MRI more commonly had nuclear β-catenin expression tumors than BRAF V600E immunopositive tumors, reflecting the differences in clinical features between ACP and PCP. Accordingly, immunohistochemistry can replace genetic analysis as an aid to determine the subtype diagnosis of CP in general medical practice.
Source: Endocrine Pathology - Category: Pathology Source Type: research