Most hormone dependent cancers become resistant to treatment after one to three years and resume growth despite hormone therapy. Previously considered "hormone-refractory prostate cancer" or "androgen-independent prostate cancer", the term castration-resistant has replaced "hormone refractory" because while they are no longer responsive to castration treatment (reduction of available androgen/testosterone/DHT by chemical or surgical means), these cancers still show reliance upon hormones for androgen receptor activation.

The cancer chemotherapic docetaxel has been used as treatment for CRPC with a median survival benefit of 2 to 3 months. A second-line chemotherapy treatment is cabazitaxel. A combination of bevacizumab, docetaxel, thalidomide and prednisone appears effective in the treatment of CRPC.

The immunotherapy treatment with sipuleucel-T in CRPC increases survival by 4 months. The second line hormonal therapy abiraterone increases survival by 4.6 months when compared to placebo. Enzalutamide is another second line hormonal agent with a 5-month survival advantage over placebo. Both abiraterone and enzalutamide are currently being tested in clinical trials in those with CRPC who have not previously received chemotherapy.

Only a subset of people respond to androgen signaling blocking drugs and certain cells with characteristics resembling stem cells remain unaffected. Therefore, the desire to improve outcome of people with CRPC has resulted in the claims of increasing doses further or combination therapy with synergistic androgen signaling blocking agents. But even these combination will not affect stem-like cells that do not exhibit androgen signaling. It is possible that for further advances, a combination of androgen signaling blocking agent with stem-like cell directed differentiation therapy drug would prove ideal.

Palliative care is medical care which focuses on treatment of symptoms of serious illness, like cancer, and improving quality of life. One of the goals of treatment in palliative care is symptom control rather than a cure of the underlying cancer. Pain is common in metastatic prostate cancer, and cancer pain related to bone metastases can be treated with bisphosphonates, medications such as opioids, and palliative radiation therapy to known metastases. Spinal cord compression can occur with metastases to the spine and can be treated with steroids, surgery, or radiation therapy. Other symptoms that can be addressed through palliative care include fatigue, delirium, lymphedema in the scrotum or penis, nausea, vomiting, and weight loss.