Decision making in intrathecal therapy for leptomeningeal disease

BACKGROUND/OBJECTIVES: Guidelines suggest intrathecal (IT) pharmacotherapy for patients with leptomeningeal disease (LMD). However, evidence on the benefit of IT treatment is limited and IT therapy is an invasive procedure in patients with limited life expectancy. Available drugs for IT therapy do not play a role in systemic treatment of the most common cancers related to LMD and it is unclear to which extent and how the recommendation for IT therapy is implemented in daily clinical practice. METHODS: A panel of 24 dedicated Swiss experts in the field of breast cancer, lung cancer, melanoma and neuro-oncology recommended by the disease group leaders of the Swiss Cancer Institute (formerly SAKK) provided their decision criteria for the use of IT treatment in LMD. Treatment strategies were converted into decision trees and evaluated for consensus and discrepancies based on the objective consensus methodology. RESULTS: We identified 11 criteria relevant for decision making in IT therapy for LMD. The criteria most often used in the decision making process were confirmed leptomeningeal disease (positive cerebrospinal fluid (CSF)), performance status, availability of systemic drugs with CNS efficacy and extra-cranial disease control. Only half of all participating experts recommend IT therapy in their daily practice. Swiss experts from the field of neuro-oncology most often recommended IT treatment whereas lung cancer experts were most reluctant. CONCLUSION: Implementation of IT pharmacotherapy in daily clinical practice varies widely both between individual experts and between experts` specialization in different cancers. Only half of the participating experts would recommend intrathecal therapy to their patients. In everyday clinical practice, treatment recommendations are highly individualized and optimal care for LMD can only be achieved involving a truly multidisciplinary team of specialists.