Practical aspects of the use of intrathecal chemotherapy.

INTRODUCTION: Intrathecal chemotherapy is frequently used in clinical practice for treatment and prevention of neoplastic meningitis. Despite its widespread use, there is little information about practical aspects such as the volume of drug to be administered or its preparation and administration.

OBJECTIVE: To conduct a literature review about practical aspects of the use of intrathecal chemotherapy.

MATERIALS: Search in PubMed/ Medline using the terms "chemotherapy AND intrathecal", analysis of secondary and tertiary information sources.

RESULTS: The most widely used drugs in intrathecal therapy are methotrexate and cytarabine, at variable doses. One of the aspects with higher variability among different studies is their potential combination with a glucocorticoid, the specific corticoid selected and its dose. The efficacy and toxicity of the different combinations have not been compared. Regarding preparation, it is worth highlighting the recommendation to adjust pH and osmolarity to the physiological range, with the aim of improving tolerability. The volume of administration can influence distribution, and recommendated range is between 5 and 12 mL. Overall, it is recommended to extract a similar volume of cerebrospinal fluid before administration. The position of the patient during and after administration can have an impact on distribution and toxicity; lateral decubitus or sitting position is recommended in the first case, and prone and/ or supine position in the second one. Most publications don't explain how the treatment has been prepared or administered, and the lack of standardization could affect results.

CONCLUSIONS: There is a great variability in practice when using intrathecal chemotherapy, despite being an effective therapy, accepted by all international groups. This uncertainty is not li mited to the drugs and doses administered, but it also includes the manner of preparation and the administration technique. The heterogeneity in clinical practice can influence the efficacy and toxicity of this therapy.