TERT Immunohistochemistry Expression as a Surrogate of TERT Promoter Mutations in Infiltrating Gliomas

Introduction/Objective

Genomic alterations are critical for the diagnosis of infiltrating gliomas. Mutations in the telomerase reverse transcriptase promoter (TERTp) are sufficient for a diagnosis of glioblastoma in some cases, independent of histologic features. Although DNA sequencing is the preferred method for evaluating TERTp mutations, there are limitations with regards to turn-around-time, accessibility, and cost. In this study, we evaluated the efficacy of using TERT immunohistochemistry (IHC) as a surrogate marker for the identification of TERTp mutations in infiltrating gliomas.

Methods/Case Report

The study cohort consisted of 31 infiltrating gliomas diagnosed following the 2016 WHO classification of CNS tumors by a board-certified neuropathologist. Each case was evaluated by immunohistochemistry (anti-TERT monoclonal antibody) and with a targeted next-generation sequencing (NGS) panel. A systemic literature search was conducted to examine reports of TERT antibody as a surrogate marker of TERTp mutations. TERTp mutation detected by sequencing was considered the gold standard.

Results (if a Case Study enter NA)

TERT immunohistochemistry demonstrated a sensitivity of 61.1% and specificity of 69.2%. Cases were divided into IDH-WT and IDH-mutant infiltrating gliomas. Among the IDH-WT group, 84% contained the TERTp mutation with a sensitivity of 62.5% and specificity of 33.3% for the TERTp IHC. IDH-mutant gliomas showed a 16.2% TERTp mutation rate, and immunohistochemistry had a sensitivity of 50% and 80% specificity. The probability of TERT immunohistochemistry in diagnosing TERTp mutations exhibited a poor likelihood ratio for both the positive and negative test. Literature review included 5 studies with an overall sensitivity and specificity remaining consistently low (<80%), with 2 of these studies evaluating CNS related tumors giving rise to similar diagnostic performance.

Conclusion

TERT IHC has suboptimal sensitivity and specificity for identifying TERTp mutations in IDH-WT and IDH- mutant infiltrating gliomas.

Critical care management of patients with acute spinal cord injury

Spinal cord injury (SCI) inevitably extends beyond neurologic consequences. The relationship between the spinal cord and its control of other organ systems make SCI management complex, requiring treatment on a multisystem approach. Patients frequently have hemodynamic instability and respiratory insufficiency secondary to the neurologic insult. Rigorous monitoring and anticipation of potential complications are essential in managing SCI, requiring a level of care provided in a neurocritical care unit. This review covers the pathophysiology, initial assessment, and stabilization in addition to acute management of cardiovascular and respiratory issues following SCI. Subsequent potential complications of deep vein thrombosis, gastrointestinal, and urinary systems and their management in the critical care setting are also addressed in this review.