The New York Times has a fascinating article on how surgeons are attempting to treat aggressive and fatal brain tumours by injecting chemotherapy drugs directly into the brain.
One of the challenges for drug makers is that there are many substances that would otherwise have an effect in the brain, but it’s very hard to get them there from the bloodstream because the blood-brain barrier filters out all but the smallest molecules.
The NYT article discusses a technique borrowed from stroke treatment to deliver chemotherapy directly to the tumour or area from where the tumour has been removed.
In certain sorts of stroke a blood clot forms and blocks blood vessels, depriving the brain of oxygen. One important treatment is called thrombolysis where doctors can inject a clot dissolving enzyme through super fine flexible tubes called microcatheters.
They can insert these into a blood vessel in the lower body and then pass them through the the network of veins and arteries until they reach the affected blood vessel in the brain, delivering the ‘clot busting’ enzyme to exactly where it’s needed.
This new technique for brain cancer has apparently borrowed this technology to deliver chemotherapy to a specific area to treat one of the deadlist form of brain tumours – the glioblastoma.
The treatment is still in the research phase, so it’s not clear it has any benefits, but the article is an interesting take on a new approach to treating this condition with a life expectancy of little over a year:
The study, which began in August, is still in its earliest phase, meaning its main goal is to measure safety, not efficacy ‚Äî to find out if it is safe to spray Avastin directly into brain arteries and at what dose. Nonetheless, the doctors were pleased when M.R.I. scans of the first few patients showed that the treatment seemed to erase any sign of recurring glioblastomas. But how long the effect will last remains to be seen…
The complexity of a study like this goes beyond the science. Clinical trials are also a complicated pact, emotionally and ethically, between desperate patients and doctors who must balance their ambition as researchers against their duty as clinicians, and must walk a fine line between offering too much hope and not enough.
Link to NYT piece ‘Breaching a Barrier to Fight Brain Cancer’.