When Does Hormone Therapy Fail for Prostate Cancer?

In the initial years of diagnosis, hormone therapy for prostate cancer can help patients with their symptoms and add years to their lives. 

For men who need (or will eventually need) hormone therapy, such as men whose prostate-specific antigen (PSA) levels are rising after surgery or radiation or men with advanced prostate cancer who don’t yet have symptoms, it’s not always clear when the best time is to start hormone treatment:

• Some doctors think that hormone therapy works better if it’s started as soon as possible, even if the patient feels well and is not exhibiting any symptoms. Studies have shown that hormone treatment may slow down the disease and perhaps even help men live longer. 
• Some doctors, however, don't agree with this approach. Because of the side effects and the risk of the cancer becoming resistant to therapy sooner, some doctors feel that treatment should not be started until cancer symptoms appear.

On average, hormone therapy can stop cancer progression for 1-2 years before the prostate cancer becomes resistant. Hormone therapy can stop working over time as the prostate cancer begins to grow again (called castrate-resistant prostate cancer). 

When this occurs, doctors may offer other therapies. Since they can’t predict how long hormone therapy will work, they may perform regular blood tests to check PSA and testosterone levels. If PSA levels start to increase and testosterone levels are low, these may be signs that the cancer has started to grow again.

While hormone therapy may help treat prostate cancer, limitations include the following:

• Hormone therapy can cause side effects that can have a significant effect on a patient’s daily life.
• Some side effects, such as breast enlargement, are permanent.
• If used alone, hormone therapy does not cure cancer, but only keeps it under control, sometimes for several years.

Long-term and excessive use of hormone therapy often cause side effects that require additional care and adapted support. 

Side effects can manifest at any point during hormone therapy treatment. Some side effects occur during treatment, whereas others develop immediately after or a few days or even several weeks later. Certain side effects can develop months or even years after treatment. Most side effects will go away once patients finish their hormone therapy. 

Short- to medium-term side effects

• Loss of libido (sex drive)
• Erectile dysfunction (inability to have an erection)
• Hot flashes
• Weight gain and muscle loss
• Breast swelling and tenderness
• Fatigue
• Irritability

Long-term side effects

• Anemia
• Osteoporosis (bone thinning)
• Changes in male sexual characteristics (shrinking of the testicles)
• Possible increase in the risk of cognitive (concentration and memory) or mood (depression) disorders
• Increased risk of cardiovascular disease (Infarction)
• Increased risk of a metabolic syndrome (diabetes, dyslipidemia, obesity, hypertension, etc.)

There are three types of hormone therapy for prostate cancer.

1. Injections or implants to stop patients from producing testosterone
2. Tablets to block the effects of testosterone
3. Surgery, called an orchiectomy, to remove the testicles or part of the testicles that produces testosterone

The most common hormone therapies used to treat prostate cancer include:

• Luteinizing hormone-releasing hormone (LHRH) agonists: These are given as regular injections. Depending on the drug, injections are given every month or every 3, 4, or 6 months.
• Luteinizing hormone-releasing hormone (LHRH) antagonists: These are administered through injections.
• Anti-androgens: These are administered through injections and implants.
• Estrogens: These are no longer a viable option because of their cardiovascular side effects.