Prostate Cancer in the Bone? Or Primary Bone Cancer?
The human skeleton is remarkable architecture. It is a framework of bone and cartilage that supports and gives shape to the body. It may be hard to imagine that bones can develop tumors, which are cells multiplying out of control, but it can happen. If it does, most of the time the tumors are benign (they won’t spread to other organs). On the other hand, if they are cancerous, breakaway tumor cells can spread and establish a bone cancer “colony” in another organ, such as the lung.
Thankfully, primary bone cancer (cancer that starts in the bone) is quite rare. According to cancer.net, fewer than 0.2% of all cancers are primary bone cancer. Treatments include surgery, radiation, chemotherapy for bone cancer, or some combination of these. Special therapies called palliative treatments are used to ease pain or manage other symptoms.
Prostate cancer metastasis to the bone
There is another type of malignant (cancerous) bone tumor called metastasis to the bone, or bone mets. This occurs when cancer cells from a tumor in another location, such as prostate cancer, break away from the primary tumor and spread through the blood stream or lymphatic system to the bone. In the case of prostate cancer, it is called prostate cancer bone mets. In fact, prostate cancer most commonly spreads to bone, possibly because of the bone’s growth factors that the cancer cells hijack.
While surgery or radiation may also be used to treat local prostate cancer tumors in the bone, systemic treatments (hormonal, chemotherapeutic, and immunotherapeutic) specifically aimed at prostate cancer will be used, since the bone mets are prostate cancer cells, NOT primary bone cancer. While not curative, they are often effective in slowing and even reducing the bone mets tumors.
Is it prostate cancer bone mets or primary bone cancer?
A recent article by a Duke Cancer Institute oncologist, Dr. Daniel George, raised an interesting point. He opened with his own experience of meeting with an advanced prostate cancer patient who says he has bone cancer. Dr. George writes, “In the past, I would smile politely and correct them by saying, ‘actually what you have is prostate cancer that has spread to your bones.’ But, what if they are right?”
Despite the very small number of primary bone cancer cases, Dr. George is implying that before administering a systemic treatment for metastatic prostate cancer, further diagnostic tests should be done to identify exactly what is growing in the bone. If it turns out to be primary bone cancer, there are several different types. Each one requires its own type of chemotherapy. And if it’s prostate cancer bone mets, which is far more prevalent than primary bone cancer, it must be treated as prostate cancer, even though it’s in the bone.
MRI-guided Focused Ultrasound (MRgFUS) to treat bone tumors
A revolutionary noninvasive called MRI-guided Focused Ultrasound (MRgFUS) can be used to manage bone pain and locally destroy most tumors. This outpatient treatment involves no surgery or radiation. Instead, under MRI guidance, beams of ultrasound are aimed at the bone tumor from numerous directions. They pass harmlessly through skin and other tissue, but when they precisely meet at the tumor, they create sufficient heat to destroy the tumor and the nerves that cause pain signals.
A 2017 paper by Singh, et al. describes how this treatment can be used to manage benign, metastatic, and primary bone cancer tumors:
Benign bone tumors were ablated with minimal adverse effects. Metastatic bone disease was successfully treated with significant decrease in pain scores. Ablated primary malignant tumors showed significant coagulative necrosis [dead tissue] on MRI… Pain scores significantly decreased 3 months after the procedure.
If you have been diagnosed with a painful benign bone tumor, primary bone cancer or bone mets, visit our website for more information. Contact us for a consultation to learn if you are a candidate for MRgFUS.
iGeorge, Daniel. “Bone is the New Primary.” UroToday.Com, March 12, 2018.
iiSingh VA, Shah SU, Yasin NR et al. Magnetic resonance guided focused ultrasound for treatment of bone tumors. J Ortho Surg. 2017 May;25(2). https://doi.org/10.1177/2309499017716256
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