Metastatic Castration Resistant Prostate Cancer
The number of FDA approved therapies for metastatic castration resistant prostate cancer has blossomed over the last decade.
American Society of Clinical Oncology has recently updated the clinical practice guidelines for systemic therapy in metastatic disease. The guideline recommends the indefinite use of androgen depravation. Chemotherapy with docetaxel is no longer recommended as firstline, in fact the guideline states lack of data to establish optimal sequence of therapies.
The therapies with proven improvement in survival and quality of life are abiraterone acetate and prednisone, enzalautamid, radium 223, docetaxel and prednisone.
Therapies with survival benefit but unclear quality of life benefits are as follow sipuleucel T, cabazitaxel and prednisone.
Abiraterone acetate (Zytiga) is an oral medication that decreases androgen production in the adrenal gland and in the tumor tissue. The most common side effects are nausea, hot flashes, increased urination, and changes in heart rate.
Enzalutamide (Xtandi) is also an oral drug that is taken once a day. Most common side effects are fatigue, hot flashes, edema, pain, and the side effect that could lead to discontinuation of the drug is seizures, which occurred in 0.9% of the patients treated with Xtandi.
Radium 223 (Xofigo) is indicated only for patients with symptomatic bone metastasis, not for visceral disease. It is an injection given six times at four-week intervals. It is associated with potential radiation risk to other persons therefore radiation protection measures need to be followed, but it gives another option which is not chemotherapy. The most common side effect is bone marrow suppression and injection site reaction.
Docetaxel was the first chemotherapy approved in the metastatic setting and in addition to the fact that is intravenous given every three weeks or weekly. The most common side effects are myelosuppression and peripheral neuropathy, which can be potentially permanent.
Sipulecl-T (Provenge) is a vaccine that must be prepared specifically for each patient. The vaccine stimulates a T-cell response against the tumor. It is an infusion and it can cause an infusion reaction and stroke within one day of administration. The most common side effect is flu like syndrome.
Cabazitaxel (Jeutana) is a new semisynthetic taxane, an intravenous chemotherapy. The most common side effects are peripheral neuropathy and bone marrow suppression. Attention must be paid to potential hypersensitivity.
The options for castrate resistant metastatic prostate cancer are numerous in 2015 and more options will be available in the near future.