Subdural Hematoma due to Dural Metastasis: A Systematic Review on Frequency, Clinical Characteristics, and Neurosurgical Management.

Background:  Subdural hematoma (SDH) occasionally accompanies dural metastasis and is associated with high recurrence rate, significantly impacting patient morbidity and mortality. This systematic review aims to evaluate the characteristics, management options, and outcomes of patients with SDH associated with dural metastasis.

Methods:  A comprehensive search of the PubMed and Cochrane databases was conducted for English-language studies published from inception to March 20, 2023, adhering to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. The authors reviewed cases of histopathologically confirmed SDH with non-central nervous system (non-CNS) tumor metastasis, focusing on therapeutic management of SDH. Statistical analysis was performed using SPSS software, with a significance level set at 0.05.

Results:  This review included 32 studies comprising 37 patients with 43 SDH cases associated with dural metastasis. Chronic SDH was the most frequently observed presentation ( = 28, 65.12%). The systemic malignancies most commonly associated with SDH due to dural metastasis were prostate carcinoma ( = 9, 24.32%) and gastric carcinoma ( = 5, 13.51%). A statistically significant association was found between metastatic melanoma and subacute SDH ( = 0.010). The majority of patients were treated with burr holes ( = 15, 40.54%) or craniotomies ( = 14, 37.84%), with no statistically significant difference in mortality rates between the two techniques ( = 0.390). Adjuvant therapy was administered to a limited number of patients ( = 5, 13.51%), including chemotherapy ( = 2, 5.41%), whole brain radiotherapy ( = 1, 2.70%), a combination of chemotherapy and whole brain radiotherapy ( = 1, 2.70%), and transcatheter arterial chemoembolization ( = 1, 2.70%). The overall recurrence rate was 45.95% ( = 17), with burr holes being the most common management approach ( = 4, 10.81%). Within a median of 8 days, 67.57% ( = 25) of patients succumbed, primarily due to rebleeding ( = 3, 8.11%), disseminated intravascular coagulation ( = 3, 8.11%), and pneumonia ( = 3, 8.11%).

Conclusion:  This review highlights the need for improving existing neurosurgical options and exploring novel treatment methods. It also emphasizes the importance of dural biopsy in patients with suspected metastasis to rule out a neoplastic etiology.