Stereotactic radiosurgery for the treatment and palliation of base of skull metastases

OBJECTIVES: Patients with skullbase metastases often present with evolving cranial nerve deficits, pain and advanced systemic disease. These factors along with declining performance status limit invasive interventions; yet, a safe, efficient treatment modality that augments palliative efforts is desirable. We herein report the role of stereotactic radiosurgery (SRS) in the management of base of skull metastases. METHODS: This retrospective institutional series reviewed 18 consecutive patients (12 male, 6 female) with of a total of 21 skullbase metastases. Seventy-five percent of patients presented with symptomatic disease most commonly consisting of pain, specific cranial nerve involvement included trigeminal (3), abducens (1), facial (2), and vestibulocochlear (3) nerves. The median prescribed dose was 18 Gy (range 15-40) with eleven of the treatments delivered as a single fraction consisting of 15-21 Gy and the most common fractionated regimen being 24 Gy delivered in 3 fractions. RESULTS: Of the eighteen patients, 10 were transitioned to hospice care and succumbed to extensive metastatic disease prior to the first imaging evaluation. Clinical and imaging follow-up demonstrated local failure in 3/8 of the remaining patients. In regards to palliation of symptoms, 5/6 of the patients with significant cranial nerve deficits reported improvement in symptoms within 1 month. Additionally, 5/5 patients with pre-treatment pain reported improvement. CONCLUSIONS: SRS is a safe, efficient, and potentially effective treatment for skullbase metastases with acceptable rates of local control. SRS leads to improvement in both pain and cranial nerve deficits and should therefore be integrated into the multidisciplinary palliation of this unique patient population.