[Diagnostic Value of Locally Produced Tumor Markers and Blood Brain Barrier Integrity in Lung Cancer Patients with Leptomeningeal Metastasis].

BACKGROUND

Tumor markers (TM) in cerebrospinal fluid (CSF) are useful for diagnosing leptomeningeal metastasis (LM). It has not been fully exploited the diagnostic possibilities of the CSF levels since the basic fact that the TM concentration of CSF depends strongly upon the serum levels as well as upon the condition of the blood brain barrier (BBB). To analyze the intrathecal TM synthesis and evaluate the integrity of BBB can be helpful for the definitive diagnosis of LM. Therefore, the aim of this study was to further explore the clinical value of intrathecal TM synthesis and BBB in the diagnosis for the lung cancer patients with LM.

METHODS

Twenty-five lung cancer patients with LM and 57 patients with nonmalignant neurological diseases (NMNDs) admitted to Nanjing Drum Tower Hospital from December 2016 to March 2020 were included. We compared the integrity of BBB and intrathecal TM synthesis between two groups, analyzed the correlation of CSF TM between the detection and intrathecal synthesis, and evaluated serial CSF cytology, the integrity of BBB and intrathecal TM synthesis when intrathecal chemotherapy for one patient.

RESULTS

Ninety-four percent LM patients showed the dysfunction of BBB, and all LM patients showed at least one intrathecal synthesized TM in CSF. In one patient, the CSF cytology was negative for the first time, but LM was eventually diagnosed based on the the intrathecal TM synthesis and positive CSF cytology of repeated lumbar puncture. In LM group, no correlation was observed between the detection and intrathecal synthesized TM in CSF. In the control group, only 3.5% (2/57) NMNDs patients had the dysfunction of BBB and no patients had intrathecal TM synthesis, both the differences of which were statistically significant (P<0.05). Finally, evaluating the CSF cytology, integrity of BBB and intrathecal TM synthesis can be used to assess the intracranial treatment effect. Moreover, intrathecal TM synthesis changes earlier than cytology.

CONCLUSIONS

The evaluation of intrathecal TM synthesis and integrity of BBB are novel clinical diagnostic tools. In addition, serial measurement of intrathecal synthesized TM may play an important role in monitoring efficacy of lung cancer patients with LM, which is worthy of further promotion and clinical application.