Surg-26. hydrocephalus in leptomeningeal disease: tandem ommaya reservoir-shunt for intrathecal chemotherapy administration

Abstract INTRODUCTION Leptomeningeal disease (LMD) is a rare late-stage manifestation of disease progression in solid and hematologic malignancies. Although advances in intrathecal therapeutic (IT) provide treatment options beyond the traditional WBRT, these IT treatment strategies are limited when LMD patients develop associated hydrocephalus. CSF shunting can improve quality of life but may lead to decreased exposure time of IT therapies, with overall survival remaining less than 4 months. Our institution implemented placement of an Ommaya reservoir with ventricular shunt for administration of intrathecal chemotherapy while allowing for concomitant CSF diversion. METHODS The authors performed a retrospective chart review on all patients who underwent placement of Ommaya reservoir with a ventricular shunt for treatment of hydrocephalic LMD from Sept 2011 to Feb 2021. LMD secondary to primary glial neoplasm were excluded. Patient demographics, clinical characteristics, tumor characteristics, systemic and IT chemotherapy regimen, length of survival and complications were assessed. RESULTS Forty-one patients were included in the study: 18 breast, 12 lung, 5 melanoma, 2 gastric, 2 diffuse large B cell lymphoma, 1 AML, 1 pancreatic. 33.3% of breast cancer were HER-2 positive, while 40% melanoma were BRAF mutated. Patients receiving IT + shunt and WBRT (n = 22) had mean survival time of 350 days from LMD diagnosis compared with 182 days for shunt and WBRT alone (n = 19; p = 0.07). Breast and melanoma patients with IT (n = 16) had improved survival compared with patients with shunt and WBRT (n = 7) alone (419 vs 91 days, p = 0.03). Kaplan-Meier survival analysis demonstrates a positive trend towards increased survival in IT + shunt and WBRT group. CONCLUSION This treatment strategy of Ommaya reservoir and shunt prolongs survival in patients with LMD and associated elevated intracranial pressures. This may be very important as we enter the era of cellular immunotherapies for LMD.