Liquid Biopsy in High-grade Gliomas and Meningiomas

cfDNA correlation with OS

To valuate whether the concentration of circulating free DNA in plasma at the time of diagnosis correlates with overall survival

Time frame: 1-3 days before surgery until patient death (or at month 12 if patient is alive)

correlation between change in cfDNA concentration after surgery and PFS and OS

To evaluate whether a reduction in plasma concentration of circulating free DNA compared to preoperative values (T0) is seen one month after the surgical procedure (T1) and if this reduction is predictive of progression-free survival and overall survival.

Time frame: from day 30 (+/- 3 days) after surgery until disease progression, patient death (or at month 12 after surgery in the absence of disease progression)

correlation between change in cfDNA concentration one month after radiotherapy completion and tumor volume changes, as well as clinical status changes

To evaluate, one month after the completion of radio (chemo) therapy (T2), the plasma concentration of circulating free DNA with respect to the pre-treatment values (T1), correlating with the volumetric and radiomic variations of the tumor in the magnetic resonance images (FLAIR sequence and T1 after injection of contrast medium), as well as with the changes in the patient's neurological status measured by the NANO score (Nayak et al., 2017) at the same timepoints.

Time frame: values assessed at month 3.5 after surgery (+/- one week) compared with values assessed 1-3 days before surgery

cfDNA concentration changes at progression

To evaluate at the time of suspected radiological progression (T3) the plasma concentration of circulating free DNA and its variations compared to the values detected one month after the end of radio (chemo) therapy (T2).

Time frame: values at the time of suspected radiological progression (or at month 12 in the absence of suspected radiological progression) compared with values assessed at month 3.5 after surgery (+/- one week)