At what stage does prostate cancer spread to bones
Prostate cancer is divided into 4 stages based on the size of the tumor, location, and extent of spread. Prostate cancer spreads to the bone if cancer is in an advanced stage or the 4th stage.
It is also known as “metastatic bone cancer” as it begins in one place and then spreads to the bone. In this stage, cancer might grow into tissues near the prostate and might have spread to nearby lymph nodes and other parts of the body, such as distant lymph nodes, bones, or other organs.
How does prostate cancer spread to bones?
In the earlier stage of advanced prostate cancer, malignant cells shed from the primary tumor (in the prostate) and migrate locally, invade blood vessels, and may disperse widely in the body.
And as the prostate cells in the bloodstream need to settle in an appropriate, they preferentially migrate to the bone. These malignant cells invade and eventually proliferate (grow tremendously) in the axial skeleton bones, such as the ribs, pelvis, and spine, where red bone marrow (spongy tissue with many blood vessels present in the center of bones) is most abundant.
Bone has a unique microenvironment that provides the conditions for the metastatic cancer cells to colonize and grow. It also produces the signaling molecules critical for prostate cancer progression into the bone.
Research is going on to target these signaling molecules that may be a potential strategy in the prevention or treatment of prostate cancer bone metastases.
Symptoms
The first sign of prostate cancer that has spread to bones is severe bone pain. Pain is triggered by cancer cells that produce changes to the structure of the bones and cause inflammation.
Sometimes it may feel like a sharp shooting pain or dull ache. It can be localized to one area or affect your whole body in some cases. The bone pain is recurrent and often worsens overnight.
Other symptoms include:
- Bone fractures or broken bones. Bone metastases weaken the bones and raise your chances of bone fractures. Due to metastatic cancers, the ribs, vertebrae, and legs are more prone to bone fractures.
- Spinal cord compression. This happens when cancer presses against the spinal cord. It may lead to weakness, tingling, or loss of balance in your limbs.
- Hypercalcemia. A high blood calcium level in the blood is known as hypercalcemia. This occurs when too much calcium escapes the bones under the effect of cancer and enters the bloodstream. It may lead to constipation, loss of appetite, frequent urination, and extreme thirst.
Diagnosis
The first thing you may feel is severe pain if the prostate cancer has gone into your bones. The location of pain will depend on which bones cancer affects. For example, you might feel hip or back pain if cancer has spread into your pelvic bones.
The doctor will recommend a digital rectal exam or an X-ray, or other test based on these symptoms. Some blood tests may also be advised to find high levels of prostate-specific antigen or PSA that show the spread of prostate cancer to bones.
Treatment
The treatment goal of advanced prostate cancer is to control or shrink the tumor growth and control symptoms. There are various options for advanced prostate cancer. Treatment options include:
1. Hormone Therapy
This therapy lowers a man’s testosterone, or hormone, levels that act as the main fuel for prostate cancer cells, so reducing its levels may slow the growth of the malignant cells.
2. Chemotherapy
Chemotherapeutic drugs are given to destroy cancer cells, and it is usually given before pain starts to prevent pain as cancer spreads to bones and other sites.
3. Immunotherapy
It uses the body’s immune system to fight cancer, and it could be a good choice for men who have no or only mild symptoms.
4. Bone-targeted Therapy
This therapy can help men with prostate cancer that has spread to the bones as they are more prone to “skeletal-related events” (SREs) that include fractures, pain, and other problems. Your doctor may suggest calcium, Vitamin D, or other drugs for your bones to stop cancer, reduce SREs and prevent pain from cancer growing in your bones.
5. Radiation
Radiation (which uses high-energy beams to kill cancer cells) can help ease pain and prevent fractures caused by prostate cancer from spreading to the bone.
Conclusion
Patients with advanced prostate cancer can develop bone metastases, leading to bone pain, fracture, and a poor quality of life. But due to recent advances in managing bone metastases of prostate cancer, the 5-year survival rate of this cancer is close to 29%.
Although the treatment doesn’t guarantee 100% cure but can help relieve pain, improve quality of life, and extend life expectancy.