Circulating brain injury biomarkers increase after endoscopic surgery for pituitary tumors

Abstract

Pituitary tumors and subsequent treatment with endoscopic transsphenoidal surgery (ETSS) may cause injury to suprasellar structures, causing long-term fatigue and neurocognitive impairment. A method to quantify brain injury after ETSS is not available. In this prospective, exploratory study of patients undergoing ETSS for pituitary tumors, a novel approach to detect possible neuronal damage is presented. Plasma concentrations of brain injury biomarkers (glial fibrillary acidic protein [GFAP], tau, and neurofilament light [NFL]) were measured the day before surgery, immediately after surgery, at day 1 and 5, and at 6 and 12 months after surgery, using enzyme-linked immunosorbent assays. The association between the increase of biomarkers with preoperative tumor extension and postoperative patient-perceived fatigue was evaluated. Suprasellar tumor extension was assessed from MRI scans, and self-perceived fatigue was assessed using the Multidimensional Fatigue Inventory before and 6 months after surgery. Thirtyfive patients were included in the analysis. Compared to baseline, GFAP showed a maximal increase at day 1 after surgery (p = 0.0005), tau peaked postoperatively on the day of surgery (p = 0.019), and NFL reached its maximum at day 5 after surgery (p < 0.0001). The increase in GFAP correlated with preoperative chiasmal compression (p = 0.020). The increase in tau was correlated with preoperative chiasmal (p = 0.011) and hypothalamus compression (p = 0.016), and fatigue score 6 months after surgery (p = 0.016). In conclusion, the concentrations of brain injury biomarkers in blood increased after ETSS for pituitary tumors. The results indicate that postoperative plasma GFAP and tau might reflect astroglial and neuronal damage after ETSS.

Age-dependent differences and similarities in the plasma proteomic signature of postoperative delirium

“…NFL was not a positive biomarker for delirium in any of our analyses. We are not unique in this regard 44 , 45 and nor do all report a relationship between plasma NFL and postoperative cognitive outcomes 46 but the different results could be explained by variations in the type and invasiveness of surgical procedures (cardiac vs. joint replacement vs. spine surgery), assay method (SOMAscan vs. proximity extension assay), or duration of postoperative follow-up. The latter is relevant because we collected our final plasma sample on postoperative day 1 and changes could have been missed because NFL peaks later.…”

Hypotension during transsphenoidal pituitary surgery associated with increase in plasma levels of brain injury markers

“…7 Although surgery for pituitary tumors performed through the transsphenoidal route is generally considered a procedure with a low risk of neuronal injury, mechanical manipulation, direct injury, and compromise of perfusion to the posterior lobe may lead to injury. 8 Furthermore, manipulation of suprasellar neuronal structures is sometimes also unavoidable. Importantly, it has been proposed that the surgical procedure itself could be partly responsible for poor outcomes, 9 which in turn might indicate that manipulation of these structures during surgery may precipitate such neuronal injury.…”

“…Importantly, it has been proposed that the surgical procedure itself could be partly responsible for poor outcomes, 9 which in turn might indicate that manipulation of these structures during surgery may precipitate such neuronal injury. 8 Following both neurological and non-neurological surgery, there is an increase in circulating levels of the brain injury biomarkers tau, glial fibrillary acidic protein (GFAP), and neurofilament light (NfL). 8,[10][11][12][13] Only one previous study has investigated the association between IOH and biomarkers of brain injury in neurosurgery.…”

“…8 Following both neurological and non-neurological surgery, there is an increase in circulating levels of the brain injury biomarkers tau, glial fibrillary acidic protein (GFAP), and neurofilament light (NfL). 8,[10][11][12][13] Only one previous study has investigated the association between IOH and biomarkers of brain injury in neurosurgery. In that study, an association was found between IOH and an increase in neuronspecific enolase (NSE) in skull base surgery following deliberate hypotension.…”

Circulating Brain Injury Biomarkers: A Novel Method for Quantification of the Impact on the Brain After Tumor Surgery

“…[8][9][10][11] We have recently shown that circulating brain injury biomarkers increase after transsphenoidal surgery for pituitary tumors in a similar temporal pattern as described after traumatic brain injury and that increased levels of the biomarker tau immediately after surgery correlates with fatigue 6 months after surgery. 12 However, the release pattern of circulating brain injury biomarkers after intra-axial brain surgery is unknown.…”