Prospective assessment of platelet function in patients undergoing elective resection of glioblastoma multiforme.

What is the context? Glioblastoma has an impact on the platelet number and the functional state of platelets. Platelets can be activated by tumor cells, and platelets count and function may impact patient survival. It has been showed an association between thrombocytosis and a decreased overall survival, with a small reduction in glioma risk associated with the long-term use of low-dose aspirin.Platelet function before and during the perioperative period in patients with glioblastoma has not been systematically investigated. Limited data suggest that platelet function may be impaired before and throughout the perioperative period, and that impaired platelet function affects clinical outcome.What is new? In this prospective study, we systematically investigated how glioblastoma provokes systemic alterations of hemostasis. We enrolled 60 consecutive patients (sample size calculated) subjected to resection of glioblastoma multiforme, and other 40 consecutive patients undergoing laparoscopic resection of colon cancer, as a comparative group, in order to differentiate hemostasis and coagulation profiles of two tumors (glioblastoma and colon adenocarcinoma) with high prothrombotic power. Forty healthy volunteers were also included to establish local reference values.We performed 1. conventional coagulation tests 2. ROTEM (rotational thromboelastometry) parameters and 3. platelet function tests, including PFA-200 closure time when stimulated by collagen/epinephrine (COL-EPI) and ROTEM platelet, using three different activators (arachnoid acid in ARATEM, adenosine diphosphate in ADPTEM, and thrombin receptor-activating peptide-6 in TRAPTEM). Variables associated with unfavorable 1-year clinical outcome were investigated, too. All these analyses were carried out at baseline (T0, time 0, before surgery) and 2 (T2), 24(T24) and 48-hour (T48) after surgery.We observed in GBR patients that platelet aggregometry, as assessed by ROTEM platelet parameters, was significantly impaired along with a shortened closure time. These changes were evident from T0 to T48. A decreased area under the aggregation curve in TRAPTEM was associated with improved survival (adjusted odd ratio (95% CI), 1.03 (1.01­1.06)).What is the impact? This study provides further evidence that patients with GBM presented a decreased platelet aggregation from before surgery and thorough the postoperative period. Decreased platelet aggregation improved clinical outcome.The cut-offs obtained can potentially to provide risk stratification for clinical outcome and to be hypothesis generating research to be confirmed by RCTs.