There are more than 4 million new cases of cancer every year, and these 5 types are most likely to cause bone metastasis!

Author: Tang Hai, Chief Physician, Beijing Friendship Hospital, Capital Medical University

Deputy Director of the Osteoporosis Group of the Orthopedic Branch of the Chinese Medical Association

Reviewer: Li Jun, deputy chief physician, Peking University First Hospital

Relevant statistics show that there are more than 4 million new cancer patients in my country every year.

Among them, many cancers will develop bone metastasis in the late stages, such as lung cancer, breast cancer, thyroid cancer, prostate cancer, and kidney cancer, which are the five tumors most likely to develop bone metastasis, accounting for about 60%-70% of all bone metastasis cancers.

Which bones are cancer cells most likely to metastasize to? What are the symptoms of bone metastasis? What are the treatments for bone metastasis? Next, let's talk about these issues that everyone is very concerned about.

1. Which bones are cancer cells most likely to metastasize to?

Distant metastasis of tumors is often achieved through the blood or lymph. Tumor growth requires a large amount of nutrients, and it will compete for nutrients from normal cells in the body to supply its own growth. Therefore, the blood-rich areas in the bones are where tumors are prone to occur, or where they are prone to metastasis.

Which bones contain more blood? Spongy bones contain abundant blood sinuses, so they are rich in blood. Any area rich in spongy bones is where the tumor is likely to recur or metastasize.

So what are the areas rich in cancellous bone? The most common are the spine and pelvis, or the epiphyses on both sides of long tubular bones, which are the most likely to have bone metastases.

Figure 1 Original copyright image, no permission to reprint

In addition, flat bones, such as ribs, scapula, etc., can also undergo bone metastasis, but it is relatively rare.

2. What are the symptoms after bone metastasis occurs?

After the tumor metastasizes to the bone, the manifestations may vary depending on the location of the metastasis. But generally speaking, there are several aspects:

The most common clinical symptom is pain, which ranks first among all metastatic cancers and is also the most uncomfortable complaint of patients.

The second is the lump. Some patients can feel the lump or the raised area where the tumor has metastasized.

The third is that the raised mass may cause some compression symptoms, such as compression of blood vessels, spinal cord, or nerves, causing problems at the distal end of the compression site. For example, compression of the distal end of blood vessels may cause necrosis, compression of the distal end of nerves may cause numbness and pain, and compression of the spinal cord may cause paralysis, which is often irreversible.

Another is pathological fracture, because bones are the most important load-bearing organs in the human body and a very important scaffold. The normal bone tissue in this scaffold is replaced by tumor tissue, so the load-bearing capacity of the scaffold will become worse. When the body bears weight, fractures will inevitably occur, which is clinically called pathological fractures.

Figure 2 Original copyright image, no permission to reprint

Once a fracture occurs, the patient will often feel very painful. In addition, in clinical practice, many patients have already had pathological fractures when they first visit the doctor, and they will ask the doctor why they have fractured their bones inexplicably without falling or bumping into them. Only then will the doctor find that it is caused by tumor metastasis.

So sometimes in clinical practice, especially for cancers like kidney cancer, lung cancer, breast cancer, and prostate cancer, the first symptom is symptoms related to bone metastasis.

3. What are the treatments for bone metastasis?

There are many treatments for bone metastasis. The first common option is radiotherapy. We can use various radiotherapy methods to reduce the size of the tumor, but the disadvantage is that in the radiotherapy channel, both normal cells and tumor cells are eaten and killed, which will cause the patient's body tolerance to drop significantly and cause greater damage.

The second is chemotherapy, which is also very common in clinical practice. There are many types of chemotherapy, which can be performed on the primary lesion or specifically on bone tissue. For chemotherapy of bone tissue, the more commonly used drugs are bisphosphonates. The main function of bisphosphonates is to inhibit the activity of osteoclasts, and tumor cells are also types of osteoclasts, so they can also play a certain therapeutic role. At present, there is also a new drug for the treatment of bone metastasis in clinical practice, denosumab, which is also a drug that inhibits osteoclast formation and is more effective than bisphosphonates.

Another method is surgery. In the past, large sections of bones would be removed and fixed. However, it was found that the tumor could not be completely removed. Therefore, surgery is now becoming more and more minimally invasive, which not only solves the patient's pain problem, but also plays a role in fixation.

The biggest benefit of minimally invasive surgery is that it makes the patient's physical condition more bearable and the impact on the patient will be relatively small. In a sense, the cost will also be reduced. Currently, the more common surgical methods in clinical practice are minimally invasive.

Of course, there are many types of minimally invasive surgery. For example, vertebroplasty is the most common surgery on the spine, while bone cement molding or bone shaping may be used on the limbs, etc. Which method is more suitable depends on specific analysis based on the specific situation.

In addition, personalized treatment is also a commonly used method in clinical practice. For example, 3D printing technology can not only accurately remove bone tumor tissue, but also reconstruct bone structure.

In short, after surgical treatment, the tumor tissue cannot be completely killed. Chemotherapy and radiotherapy are needed to cooperate, and even the primary lesion needs to be treated. This is a holistic treatment process, which requires mutual cooperation for comprehensive treatment.