Identification of a candidate biomarker from perfusion MRI to anticipate glioblastoma progression after chemoradiation

{To identify relevant relative cerebral blood volume biomarkers from T2* dynamic-susceptibility contrast magnetic resonance imaging to anticipate glioblastoma progression after chemoradiation. Twenty-five patients from a prospective study with glioblastoma, primarily treated by chemoradiation, were included. According to the last follow-up MRI confirmed status, patients were divided into: relapse group (n = 13) and control group (n = 12). The time of last MR acquisition was t(end); MR acquisitions performed at t(end-2M), t(end-4M) and t(end-6M) (respectively 2, 4 and 6 months before t(end)) were analyzed to extract relevant variations among eleven perfusion biomarkers (B). These variations were assessed through R(B), as the absolute value of the ratio between a dagger B from t(end-4M) to t(end-2M) and a dagger B from t(end-6M) to t(end-4M). The optimal cut-off for R(B) was determined using receiver-operating-characteristic curve analysis. The fraction of hypoperfused tumor volume (F_hP(g)) was a relevant biomarker. A ratio R(F_hP(g)) aeyenaEuroe0.61 would have been able to anticipate relapse at the next follow-up with a sensitivity/specificity/accuracy of 92.3 %/63.6 %/79.2 %. High R(F_hPg) (aeyen0.61) was associated with more relapse at t(end) compared to low R(F_hPg) (75 % vs 12.5 %