Object. Twenty-two patients who had solitary metastatic brain tumors with dural extension were treated surgically over a 3-year period. Their cases were reviewed to characterize these lesions and to compare the patients with a similar cohort in which there was no dural involvement.
Methods. The median age of the patients was 58 years (range 11–68 years) and the male/female ratio was 12:10. The median preoperative Karnofsky Performance Scale (KPS) score in the group was 90 (range 70–100). The most common histological diagnoses seen in these patients included breast cancer, adenocarcinoma and squamous cell carcinoma of the lung, and renal cell carcinoma. All patients underwent gross-total resection of the tumor and 86% received radiation therapy. The median patient survival time was 11 months, with a median time to recurrent intracranial disease of 19 months. Survival was related to the histological diagnosis. Recurrent disease occurred in 41% of cases. Leptomeningeal disease occurred in three patients (14%). The frequency and time course of development of recurrent disease was not affected by dural resection nor was survival.
These results for patients having metastatic brain tumors with dural extension were compared with those for a cohort of 26 patients in which there were similar histological diagnosis, age, gender, and preoperative KPS score were distributed similarly but in which each patient had a single subcortical metastatic lesion. Those patients had a median survival of 10 months and the median time to recurrence was not reached. Leptomeningeal disease occurred in one patient (4%).
Conclusions. To the authors' knowledge, this is the first reported series of patients with metastatic brain tumors with dural extension. Patients with this disease may be more likely to develop recurrences along the dura and leptomeningeal disease, but the overall survival time in these patients is not different from those patients with intraparenchymal lesions.