1427P - Exploration of the value of leptomeningeal biopsy in diagnosing and treating non-small cell lung cancer with leptomeningeal metastasis

Background

To explore the value of ventriculoperitoneal (VP) shunting combined with leptomeningeal metastasis (LM) biopsy in diagnosing and treating driver mutation-positive non-small cell lung cancer patients with LM (NSCLC-LM).

Methods

We retrospectively analyzed 32 driver mutation-positive NSCLC-LM patients who underwent VP shunting or Ommaya reservoir implantation from June 2019 to June 2021. Pathological result of the LM biopsy, post-operative adverse events (AE), and clinical outcomes were analyzed.

Results

Of the 32 recruited NSCLC-LM patients, tumor was detected from LM biopsy from 21 patients, leading to a detection rate of 65.6% (21/32). LM sample from one patient underwent genomic profiling and was found to harbor EGFR rare mutations p.G719S and p.L816Q and mutated TP53. Median overall survival was 16.8 months (95% confidence interval [CI] 8.7-24.8) since LM diagnosis and 10.6 months (95% CI 7.2-13.9) since VP shunting or Ommaya reservoir implantation. postoperative complications included intracranial infection (1/32, 3.1%), incisional surgical site infection (1/32), perioperative mental disorders (1/32). All AEs were Grade 1 or 2 and improved upon treatment.

Conclusions

LM biopsy is safe and feasible for driver mutation-positive NSCLC-LM patients. Importantly, LM biopsy can be used to diagnose otherwise difficult cases and identify actionable genomic alterations for targeted therapy.

Clinical trial identification

Editorial acknowledgement

Legal entity responsible for the study

Linbo Cai.

Funding

Has not received any funding.

Disclosure

The author has declared no conflicts of interest.