Lesion Network Mapping Analysis Identifies Potential Cause of Postoperative Depression in a Case of Cingulate Low-Grade Glioma

Background: Depression following resection of diffuse low-grade glioma has rarely been described. Location of the tumor and surgical route are potential causes. Lesion network mapping (LNM), leveraging high-quality resting-state functional magnetic resonance imaging data from large samples of healthy adults, has been used to explore the broader network connectivity for given lesions. However, LNM has not been applied to large intra-axial masses or surgical lesions. We used LNM to examine a potential cause of postoperative depression in a patient with a cingulate diffuse low-grade glioma (zones I–III). Case Description: A 34-year-old woman underwent surgery for medically refractory seizures attributable to diffuse low-grade glioma. Near-total resection was attained via a single-stage, transcortical route through the medial prefrontal cortex. Despite freedom from seizure and lack of tumor growth at 42 months of follow-up, she developed symptoms of major depressive disorder soon after surgery that persisted. To identify functional networks potentially engaged by the surgical corridor and tumor resection cavity, both were segmented separately and used as seeds for normative resting-state functional magnetic resonance imaging connectivity mapping. To study depression specifically, networks associated with the tumor and surgical approach were compared with networks associated with subgenual cingulate deep brain stimulation. LNM results suggested that the surgical corridor, rather than the tumor, had greater overlap with deep brain stimulation–based depression networks (32% vs. 8%). Conclusions: Early postoperative development of major depressive disorder following resection of a cingulate region tumor, although likely multifactorial, should be considered and patients appropriately counseled preoperatively. Further validation of LNM as a viable methodology for correlating symptoms to lesions could make it a valuable tool in selection of surgical approach and patient counseling.