[Guideline 'Leptomeningeal metastases of solid tumours']

In view of recent progressive insight in the diagnosis and treatment of leptomeningeal metastases of solid tumours, a new guideline has been designed on the initiative of the Dutch Association of NeuroOncology and the Netherlands Society of Neurology, with methodological support from the Dutch Institute for Healthcare Improvement (CBO). - There are no neurological symptoms or signs, nor MRI characteristics that are unique to leptomeningeal metastasis. However, clinical suspicion of leptomeningeal metastasis in a patient known to have cancer, in combination with specific MRI characteristics is sufficient to make the diagnosis. If MRI or CT results are negative or inconclusive cerebrospinal-fluid assessment should be conducted. - Management of care of patients with leptomeningeal metastasis without brain metastases can be based on a series of categories that have been developed using prognostic factors such as Karnofsky performance status, serious encephalopathy or neurological dysfunction, systemic disease, sensitivity of the tumour for chemotherapy or hormonal treatment - In the context of meaningful palliation, systemic treatment, if necessary in combination with radiotherapy to clinically relevant sites, is preferable to intrathecal chemotherapy. - Intrathecal chemotherapy combined with local radiotherapy is recommended if effective systemic treatment is not available, and if the tumour is potentially sensitive to methotrexate, cytarabine or thiotepa. The combination of intrathecal methotrexate and whole-brain radiotherapy should be avoided.