New Ultrasound Treatment Controls Pain from Kidney Cancer Bone Mets

How frequently do you hear about kidney cancer? Chances are, not very often. Yet kidney cancer (also called renal cancer) is one of the 10 most common cancers. While more men than women are diagnosed with kidney cancer, nearly 64,000 new cases occur in the U.S. annually.

When kidney cancer is diagnosed early, 5-year survival rates are high. According to the Integrated Staging System developed by UCLA:

• For patients with localized kidney cancer (cancer that had not spread to the lymph nodes or distant organs), 5-year survival rates were 97% for the low-risk group, 81% for intermediate-risk group, and 62% for the high-risk group.
• For patients with kidney cancer that had spread to the lymph nodes or distant organs when it was first found, 5-year survival rates were 41% for the low-risk group, 18% for intermediate-risk group, and 8% for the high-risk group.

It is estimated that at the time of diagnosis, 20-50% of patients will be found to have kidney cancer that has begun to grow beyond the organ, or has already spread (metastasized) to distant locations.ⁱ

Where does kidney cancer spread?

Kidney cancer has the capacity to travel to lymph nodes, other organs (often the lungs, liver, or brain), and to bones. This is called metastasis, meaning spread. The most common site is the lungs, representing about 45% of metastatic cases. The second most common site is bone, comprising roughly 30% of kidney cancer metastasis. When kidney cancer spreads to the bone, it is called kidney cancer bone metastasis, or bone mets.

Sometimes, kidney cancer bone mets are detected by imaging even before there are symptoms. However, for many kidney cancer patients, the first indication of bone mets may be one or more of the following:

• Pain
• Bone fracture
• Spinal cord compression
• High calcium levels (hypercalcemia)

New treatment for painful kidney cancer bone mets – MRgFUS

Many people don’t realize that bone is made up of living tissue that continually exchanges new bone for old. In addition, bones have blood vessels, nerves, and pain receptors. A metastatic lesion (tumor) from kidney cancer “hijacks” the bone’s resources to nourish itself and grow, which disrupts normal bone processes. As the lesion grows, it can cause nerve pain in the bone, and this can become severe enough to lower a patient’s quality of life. Thankfully, there is a new noninvasive treatment that can deaden nerve pain while also targeting the bony lesion itself. It is called MRI-guided Focused Ultrasound, or MRgFUS.

MRgFUS uses Magnetic Resonance Imaging to identify the bone lesion that is the source of pain. Once this is done, the imaging is used to plan treatment. The treatment consists of “beams” of ultrasound energy, or sound waves) aimed at the lesion from several different angles. Although these energy waves are harmless as they travel through tissue to their target, where they converge, they generate a high temperature that destroys the tumor and its nerves that transmit pain messages.

MRgFUS has been likened to using a magnifying glass to focus sunlight onto a small spot. The light waves themselves are not hot enough to do damage, but where the lens aims them into a single spot, it will become hot enough to cause a burn. MRgFUS is similar, though the temperature is much higher.

MRgFUS can be applied to metastatic bone lesions in the ribs, breastbone, arms or legs, shoulders, and certain areas of the lower back spine/tailbone. Patients must be examined to ensure that MRgFUS is an appropriate treatment for them.

Results of MRgFUS

Patients with severe bone pain prefer MRgFUS over traditional bone surgery or radiation. MRgFUS has the following benefits:

• MRgFUS does not involve any physical penetration (no cutting, no risk of infection, no post-surgery pain)
• MRgFUS is an outpatient procedure, performed inside the bore (tunnel) of the MRI machine
• MRgFUS has no exposure to radiation
• MRgFUS is effective with only one treatment
• MRgFUS has very quick results – unlike radiation, which can take weeks to begin reducing pain. 71% of MRgFUS patients report greatly reduced pain in a week or less
• Patients return to normal activity within days
• MRgFUS produces lasting pain relief. One study reports substantial pain relief at 3 months after treatment for 65% of patients.

Sperling Medical Group offers MRgFUS

The Sperling Medical Group offers MRgFUS for patients with painful kidney cancer bone mets. Our facility is equipped with a state-of-the-art powerful magnet that is fully integrated with Focused Ultrasound technology using the Exablate system. For more information, contact our Center or visit our website.

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ⁱChen XY, Lan M, Zhou Y, Chen WZ et al. Risk factors for bone metastasis from renal cell cancer. J Bone Oncol. 2017 Nov 2;9:29-33. Full article at https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5684431/