On Cancer: Neurosurgeon Mark Bilsky on Stereotactic Radiosurgery for Spine Tumors

Stereotactic radiosurgery is an advanced type of external radiation therapy that delivers extremely precise, very intense doses of radiation to eliminate tumors. Physicians at Memorial Sloan-Kettering’s Spine Tumor Center have pioneered the use of stereotactic radiosurgery as a key form of treatment for people with spine tumors. Their work has shown stereotactic radiosurgery to be highly effective at eliminating tumors while avoiding injury to the spinal cord.

In an interview, neurosurgeon Mark Bilsky, director of the Spine Tumor Center, explains how stereotactic surgery has changed spine tumor treatment at Memorial Sloan-Kettering.

What is the Spine Tumor Center?

The Spine Tumor Center has evolved to become a highly specialized multidisciplinary team that works together closely on all problems related to spine cancer. Our team of more than 20 members includes neurosurgeons, radiation oncologists, neurologists, neuroradiologists, orthopaedic surgeons, pain management experts, rehabilitation specialists, and anesthesiologists who work only on spine procedures.

Nurses also play a critical role because they specialize in caring for people with spine tumors. Having a team focused just on spine tumors has enabled us to improve the care we provide in remarkable ways.

The Spine Tumor Center has grown dramatically over the past five to seven years. When I arrived at Memorial Sloan-Kettering in 1995, we performed about 40 procedures on spine cancer patients each year. Last year we performed more than 800 procedures and cared for more than 1,500 patients.

What are some of the most significant recent developments in spine tumor treatment?

Perhaps the greatest advance in the treatment of spine tumors has been the evolution of stereotactic radiosurgery and its integration into the treatment plan for many patients. Stereotactic radiosurgery is an incredibly precise form of radiation therapy that delivers very high doses of radiation to a tumor in just a few treatment sessions.

Most solid tumors, with the exception of breast cancer and prostate cancer, don’t respond well to conventional external beam radiation therapy, but they respond dramatically well to stereotactic radiosurgery. We’re now able to control about 95 percent of tumors in the spine for up to five years when we use stereotactic radiosurgery as a first treatment approach.

When do you use traditional surgery to treat spine tumors?

Because stereotactic radiosurgery is so effective, only a small percentage of patients with spine tumors require traditional surgery. We typically perform surgery when a tumor is compressing the spinal cord or a patient has significant instability in the bones of the spine.

How do neurosurgeons and radiation oncologists at Memorial Sloan-Kettering work together to treat spine tumors?

In the past, when neurosurgeons performed major operations to remove spine tumors, many patients experienced a recurrence of cancer in the spine. Today, with neurosurgeons and radiation oncologists working together, we have every expectation that we will control the tumor using stereotactic radiosurgery.

Even when we use this approach after traditional surgery, we are typically able to control the tumor. As surgeons, our strategy has shifted. We now know that we don’t need to take out every bit of tumor surgically. What we really need to do is relieve the pressure that the tumor is placing on the spinal cord and stabilize the spine to make it possible to do radiosurgery.

Interventional radiologists can stabilize the spine using vertebroplasty and kyphoplasty, or surgeons can place specialized bone screws in minimally invasive ways through skin. Then, we can use stereotactic radiosurgery to treat the tumor.

We’ve looked at about 200 patients where we’ve used stereotactic radiosurgery following open surgery. The local rates of control are very similar to what we’re seeing when we use stereotactic radiosurgery as a primary treatment, with greater than 90 percent tumor control at one-year follow-up.

In addition to the advanced treatment options, how does the multidisciplinary setting of the Spine Tumor Center benefit patients?

In our Spine Tumor Clinic, doctors specializing in neurosurgery, radiation oncology, and interventional radiology all work in the same clinic at the same time. This makes it easier and more efficient for us to take care of patients’ needs, rather than having them see one specialist one day and then asking them to come back several days later to see another doctor. It has been a dramatic improvement in patient care, both in terms of convenience and safety.