The Possible Role of Wnt/β-Catenin Pathway in Central Neurocytoma

Central neurocytoma (CN) is a rare intraventricular tumor with unclear molecular features. Ki-67 indices more than 4% indicate aggressive behavior, classifying these as atypical central neurocytoma (ACN). Pathway alteration studies revealed limited results. Despite histological similarities to oligodendrogliomas, CNs lack definitive molecular markers, necessitating alternative diagnostic approaches.

In this study, we aimed to explore the involvement of the Wnt/β-catenin signalling pathway in CN by evaluating the immunohistochemical expressions of β-catenin and lymphoid enhancer-binding factor 1 (LEF-1). We have documented a total number of 15 CNs. Among 15 cases, 4 were in the atypical category.

Patient ages were between 11 and 47 years. Ki-67 indices in ACN cases were 7%, 7%, 9%, and 15%. β-catenin demonstrated diffuse membranous staining without any nuclear positivity in 12 cases. Three cases had focal nuclear expression in addition to patchy membranous staining. The nuclear β-catenin positivity was between 3% and 5%. Among these 3 cases, 1 was ACN and showed 5% nuclear positivity. These 3 cases also demonstrated scattered nuclear positivity with LEF-1. Nuclear staining with LEF-1 was weak and highest in the ACN case with 3% nuclear positivity. There was no additional case staining with LEF-1.

The rarity of CN is a limitation to discover its nature. There is no evidence for the possibility of targeted therapies. Still, there are few findings suggesting the involvement of the Wnt/β-catenin pathway. Although our findings may suggest some alterations of this pathway, they are limited to make an interpretation. Multicenter studies have great importance in clarifying genetic modifications in CN and the possibility of targeted therapies.