Cytotoxic T Cells and their Activation Status are Independent Prognostic Markers in Meningiomas.

Purpose: Clinically aggressive meningiomas (MGMs) are rare but treatment-resistant tumors in need for more effective therapies. Because tumor-infiltrating T lymphocytes (TILs) are essential for successful immunotherapy, we assessed TIL numbers and their activation status in primary (p-) and recurrent (r-) meningiomas and their impact on survival.

Experimental Design: Presence of TILs was analyzed in 202 clinically well-annotated cases ( = 123 pMGMs and = 79 rMGMs) focusing on higher-grade meningiomas [ = 97 World Health Organization (WHO) °II, = 62 WHO°III].

Transcriptomic analysis of aggressive meningiomas identifies PTTG1 and LEPR as prognostic biomarkers independent of WHO grade.

Meningiomas are frequent central nervous system tumors. Although most meningiomas are benign (WHO grade I) and curable by surgery, WHO grade II and III tumors remain therapeutically challenging due to frequent recurrence. Interestingly, relapse also occurs in some WHO grade I meningiomas.