Objective:

Background:

LMD occurs primarily in glioblastoma patients with prolonged survival and those who undergo aggressive treatment courses. Targeted therapies such as GammaTile (which contains cesium-131 radiation emitting seeds) or LITT provide good localized disease control following recurrence and serve as immediate treatment in the weeks leading up to radiotherapy or systemic treatment. Here we present a case series of patients who received localized therapy with GT or LITT who soon thereafter developed LMD.

Design/Methods:

We retrospectively reviewed all patients at our institution with high grade astrocytoma who were treated with either GammaTile or LITT and were later found to have disseminated disease into the leptomeningeal space. DNA/RNA sequencing, NGS and immunohistochemistry of tumor tissue were performed at both original diagnosis and time of GammaTile placement or LITT procedure. LMD was diagnosed through MRI brain/spine findings. Cases were analyzed for time to development of leptomeningeal dissemination, median overall survival, survival from time of leptomeningeal dissemination diagnosis, and time of leptomeningeal dissemination diagnosis to second radiation therapy. 

Results:

Out of 90 high grade astrocytoma patients treated with GammaTile therapy or LITT following recurrence, 5 had progression to leptomeningeal dissemination. Two patients had multifocal tumor, and another had contralateral progression prior to LMD. The median overall survival after leptomeningeal dissemination was 6.5 months (range 0.1–28.5) for astrocytoma and only 3.8 months (range 0.1–32.6) for glioblastoma.

Conclusions: