Pan-TRK expression and NTRK gene aberrations in meningiomas: association with tumor grade and proliferative activity.
Summary
This study investigated pan-TRK expression and NTRK gene aberrations in meningiomas. The findings indicate that pan-TRK expression is common in these tumors, especially in high-grade cases and those with high proliferative activity. While pan-TRK immunohistochemistry may assist in differentiating meningiomas from other central nervous system tumors, NTRK gene aberrations are rare. Therefore, molecular confirmation is crucial to identify patients who could benefit from TRK-targeted therapies.
Analysis
🔴 CLINIQUE: This retrospective study suggests that pan-TRK immunohistochemistry could serve as a preliminary prognostic and diagnostic biomarker for meningiomas, as it is associated with higher tumor grade and increased proliferation. It might also aid in differentiating meningiomas from other CNS tumors. However, its predictive utility for targeted therapies is limited by the rarity of NTRK fusions, necessitating complementary tests like FISH or NGS. Direct clinical impact on treatment guidelines is still distant (5+ years), but this warrants prospective studies. 🟢 BIOMOL: The discovery of frequent pan-TRK expression in meningiomas, especially high-grade ones, is a significant finding. The study utilized pan-TRK IHC as a screening tool, validating positive cases with FISH for NTRK gene aberrations. While IHC is a sensitive tool for detecting protein expression, its specificity for fusions is low in this context, as only 16.7% of IHC-positive cases showed a gene aberration. This highlights the importance of molecular validation (FISH or NGS) to identify actionable NTRK fusions, enabling a translational approach towards targeted therapies.