What is the life expectancy of someone with stage 4 prostate cancer?

The life expectancy of someone with stage 4 prostate cancer can vary widely depending on a variety of factors, such as the type and grade of the tumor, whether metastasis has occurred and where it has spread, overall health of the individual, response to treatments like chemotherapy or radiation therapy, etc. A recent study in 2019 by physicians at Johns Hopkins revealed that survival rates varied significantly across all stages of prostate cancer.

For stage 4 prostate cancer specifically (which usually indicates that the cancer has spread, or metastasized to other parts of the body), about 34% survived for 5 years following diagnosis. Of course, due to varying factors such as those mentioned above some individuals may live much longer. Some cases have been reported in which life expectancy exceeds 10 years after a stage 4 diagnosis.
In general though there is no specific answer as it entirely depends on how well each individual responds to treatment and any underlying health conditions one may have. Ultimately it is best for anyone diagnosed with stage 4 prostate cancer to consult their doctor who can provide more detailed information regarding potential prognosis.