Over the past decade, several groups have identified molecular markers to better classify meningiomas. In 2019, Drs. Patel, Klisch, and others at Duncan NRI and Baylor College developed a molecular classification system (group A-C with C being the most aggressive) that was able to predict tumor recurrence with far greater precision than the WHO grading scale. Last year, recognizing the prognostic value of these molecular markers, WHO included a molecular marker – the loss of both copies of two tumor suppressor genes – as a criterion for grade 3 meningioma classification.
In the present study, Drs. Patel, Klisch, and their collaborators examined 776 meningioma tumors of all grades obtained from patients enrolled in four different institutions.
While tumors recurred within 47 months (~ 4 years) of surgery in at least half of typical group C meningioma patients, they recurred much more quickly (within 11-25 months or 1-2 years of surgery) in the subset of group C patients who were also deficient for CDKN2A/B. Furthermore, the team found that the loss of just a single copy of CDKN2A/B resulted in as poor a prognosis as the loss of both copies of these genes.
“Based on these findings, we think in order to accurately prognosticate meningioma patients, the first step should be to identify if they have group C (aggressive) tumors and then to further refine their diagnosis by checking for the loss of one or both copies of CDKN2A/B,” said lead author, Dr. Patel who is also a neurosurgeon.
“Thus, this study emphasizes the need for greater post-surgical care and clinical counseling of this subset of meningioma patients as well as raises the future possibility of having these patients undergo radiation immediately after surgery to reduce recurrence.”