A new paper in the journal Neurosurgical Focus finds the use of laser beneficial for the removal of large, "inoperable" glioblastoma (GBM) and other types of brain tumours.

The paper is authored by Andrew Sloan, MD, and colleagues from University Hospitals Cleveland Medical Center, Case Western Reserve University School of Medicine and Case Comprehensive Cancer Center.

Dr. Sloan and other investigators at the Case Comprehensive Cancer Center led the first in human trials, published in 2013, of a procedure with laser interstitial thermotherapy (LITT), a minimally invasive approach using a laser to "cook" a tumour through a tiny hole in the scalp and bone and the intra-operative MRI (iMRI) to fine tune the treatment rather than the surgeon's direct vision.

However, one problem that he and other surgeons faced was tumour swelling.

While LITT was successful for brain tumours smaller than the size of a golf ball, larger tumours often swelled following LITT, sometimes threatening the life of the patient.

This was initially disappointing to Dr. Sloan as these larger tumours, especially "butterfly" gliomas, usually considered inoperable using conventional approaches, were the very ones he had hoped LITT would allow him to treat.

But during an operation to remove the swelling, Dr. Sloan made a surprising finding.

The cooked tumour, rather than being tense and bloody as he expected, was soft, and its blood supply had been clotted off.

This gave him the idea that he could treat even the larger inoperable tumours safely with LITT if he combined it with a very small craniotomy (a small opening in the head) which would allow him to "suck out" the cooked tumour to prevent swelling.

The Neurosurgical Focus paper (and an accompanying video) describe this treatment on 10 patients who had difficult-to-access malignant tumours.

The tumours had a median volume of 38 cc.

Eight patients had GBMs including "butterfly GBMs," one had previously treated GBM, and one had a melanoma brain metastasis.

GBM is the deadliest of brain tumours and patients with them have a very poor prognosis.

Since the study, six patients remain alive and four have died.

"I am very excited by the results of this study. This procedure is a new option for patients with these large malignant tumours," said Dr. Sloan. "We have seen similar results and overall survival compared to LITT procedures performed in patients with smaller lesions and with lower risk."

"We feel with further studies, LITT will continue to develop into a safer, more user-friendly technique that may help remove more of these deadly tumours than surgery alone can accomplish," said Dr. Sloan.

Source: University Hospitals