Metastatic Brain Cancer and Leptomeningeal Disease - 1264444

Unfortunately, there are no particularly effective therapies for leptomeningeal carcinomatosis in the setting of lung cancer, and it remains a very difficult complication to manage. Though some patients have done well with pulsed Tarceva (erlotinib), that may really be applicable mostly or entirely in the minority of lung cancer patients with an EGFR mutation. This remains an under-studied situation, because it's still infrequent, and many patients are too debilitated to participate in any kind of trial and can't wait to go through the time-consuming regulatory process of trials -- so this means that we're left just grappling the best we can with very little evidence.

Good luck.

-Dr. West

I was diagnosed with leptomeningeal carcinomatosis in January. I immediately underwent treatment infusions with methotrexate (MTX) via a ommaya reservoir. Fortunately, the MTX treatment was successful and I currently show no evidence of disease. I'm still taking MTX every three weeks though as a maintenance treatment.

Would MTX be a viable treatment for dashiod? How does MTX compare with pulse dose Tarceva?

Methotrexate directly injected into the cerebrospinal fluid (CSF) via an Ommaya reservoir is a longstanding default option that hasn't tended to be as helpful in lung cancer as it has in breast cancer and some other settings. It certainly hasn't been the subject of enough research to know how it formally compares with pulsed Tarceva. I suspect it may well be a stronger option for someone who isn't EGFR mutation-positive, and potentially a less favorable option for someone who is EGFR mutation-positive, but it also hasn't tended to dramatically improve someone's clinical status as much as potentially help an asymptomatic patient with very subtle, perhaps mild leptomeningeal disease convert their CSF from being positive for cancer cells to negative.

But yes, direct injection of methotrexate into the CSF remains one of the limited options that would be entertained -- it's just that many lung cancer experts and general oncologists alike have not seen sufficient benefit from this practice to lead to it being a clear standard approach.

-Dr. West

Hi Dash,

Yes, that is true. An exon 21 EGFR mutation indicates that your dad's cancer may be particularly sensitive to treatment with an EGFR inhibitor such as Tarceva, and it would normally be the preferred treatment regimen.

I hope he responds well to Tarceva.

JimC
Forum moderator

Yes, while there's no clear "best" EGFR inhibitor, one EGFR tyrosine kinase inhibitor or another is the clear leading recommendation in this setting for someone with an activating EGFR mutation (exon 19 or exon 21).

Good luck.

-Dr. West