Surgical Resection Of Brain Metastases And The Risk Of Leptomeningeal Recurrence In Patients Treated With Gamma Knife Stereotactic RadiosurgeryDaniel Krauss1, Evelyn Martinez1, Daniela Greto1, Ann Maitz1, Inga Grills1, Hong Ye1, Peter Chen11William Beaumont Hospital, Royal Oak, MI, USA Keywords: brain metastasis, gamma knife, outcome, recurrent disease, resection
Leptomeningeal spread of disease portends a dismal prognosis in patients with brain metastases. As more patients with brain metastases are treated with radiosurgery (RS) only (no whole brain radiotherapy), the risk of occult leptomeningeal disease is not being addressed. Surgical disruption of anatomic barriers could theoretically facilitate the spread of malignancy along this route.
This analysis was conducted to determine whether or not prior surgical resection increases the risk for future leptomeningeal failure in patients treated postoperatively with RS alone.
279 patients treated for brain metastases at the William Beaumont Hospital Gamma Knife center with a minimum follow-up of 3 months were included in this analysis.
Kaplan-Meier long-rank estimates of the development of leptomeningeal disease at 1 and 2 years were used. Time to failure was measured from the date of diagnosed brain metastasis to the date of either radiologically (MRI) or pathologically (CSF cytology) documented leptomeningeal disease.
Median follow-up for the entire group was 1.6 years. 80 of the 279 patients (28.7%) in this series underwent surgical resection prior to Gamma Knife RS. Leptomeningeal disease developed in a total of 13 patients with 1- and 2-year actuarial rates of 2.0% and 4.6%, respectively. 6 patients of the 80 undergoing surgery and 7 patients of the 199 with no surgery developed leptomeningeal recurrence corresponding to 2-year rates of 5.4% and 4.4%, respectively (p=0.57). Mean time to the development of leptomeningeal failure was 2.2 years in patients having had surgery vs. 1.4 years in those who had no surgery (p=0.12). Patients with a primary breast cancer histology (p=0.03) were significantly more likely to develop leptomeningeal spread of disease compared to other primary tumor types. Neither gender, patient age, nor prior administration of chemotherapy was associated with altered risks of leptomeningeal failure.
This is a retrospective study.
Leptomeningeal recurrence is relatively rare in the setting of brain metastases treated with RS alone.
Prior surgical resection failed to significantly predict for leptomeningeal failure. Project Roles:
D. Krauss (), E. Martinez (), D. Greto (), A. Maitz (), I. Grills (), H. Ye (), P. Chen ()