Cerebrospinal Fluid Cytology-guided Intrathecal Chemo-holiday Therapy for EGFR-positive NSCLC Leptomeningeal Metastases

The pemetrexed is administrated by intrathecal injection with a dose of 50mg, once per week for 4 weeks, followed by every four weeks thereafter. The cerebrospinal fluid(CSF) samples are collected every 4 weeks and the cytology examination will be performed. If CSF cytology was negative, CSF cytology was tested again 1 week later. Two negative tests were considered as negative CSF cytology. If the cytology of cerebrospinal fluid was negative after 4 consecutive intrathecal injections, the intrathecal injection should be stopped. If positive, continue to give a intrathecal injection every 4 weeks until CSF cytology is negative. If CSF cytological positivity or worsening of neurological symptoms occurs again during discontinuation, or if new symptoms appear, the intrathecal injection should be resumed every 4 weeks.

double dose of vometinib (160mg)