Safety and feasibility of Ommaya reservoir for intrathecal chemotherapy in patients with leptomeningeal disease.

[AIM OF THE STUDY] To assess safety and feasibility of intrathecal chemotherapy (IC) and disease monitoring via Ommaya reservoir (OR) in routine clinical practice in patients with leptomeningeal disease (LMD).

[CLINICAL RATIONALE OF THE STUDY] Leptomeningeal disease carries poor prognosis with an average survival of 3-6 months after diagnosis. OR are an accessible alternative to serial lumbar punctures for delivery of IC and disease monitoring in these patients but are not widely used, partially due to safety concerns.

[MATERIAL AND METHODS] This single-center retrospective cohort study enrolled patients who received at least one administration of IC via OR for LMD between 2017 and 2022 at a tertiary academic center. Demographics, primary malignancy, treatment type, complications, adverse events and outcomes were recorded for each enrolled patient.

[RESULTS] We identified 22 patients (17 females, 5 males) with mean age 50.9 ± 14.8 years. The primary cancers were breast (12), leukemia (3), ovarian carcinoma (3), CNS lymphoma (1), urothelial carcinoma (1), spinal melanocytoma (1), and high-grade glioma (1). A total of 208 IC injections via OR were performed [median 9 OR injections per patient (interquartile range (IQR) 5-13)]. Five patients (23%) experienced mild adverse events of grade 2 or lower by Common Terminology Criteria for Adverse Events. The overall risk of adverse events from injections was 3.4% (7/208). Eight patients (36.3%) converted into negative CSF cytology and 18 patients (82%) had clinical and/or radiological progression of their LMD (median 2 months following first injection). Eleven patients (50%) died of their LMD during follow-up. Median OS and PFS from the first injection were 5.3 months [95% CI: 4.8-NE (not estimable)] and 4.3 months [95% CI: 1.8-16.0], respectively.

[CONCLUSIONS AND CLINICAL IMPLICATIONS] Our single-center cohort study suggests that the use of intrathecal chemotherapy via Ommaya reservoir in routine clinical practice is a safe and feasible option and should be considered for treatment and frequent disease monitoring in eligible patients with leptomeningeal disease. Neurologists, especially neuro-oncologists, can significantly contribute to the care of patients of leptomeningeal disease via administering intrathecal chemotherapy.