What to Know About the Latest in Prostate Cancer Treatment
Experts explain news findings and treatments on the horizon
Prostate cancer grows so slowly in some men that doctors often recommend active surveillance or watchful waiting instead of more aggressive treatment. In fact, one study from the Johns Hopkins Active Surveillance Program found that less than 1% of men with low-risk prostate cancer developed metastatic disease after 15 years of active surveillance.
But if prostate cancer grows slowly, the same can’t be said for research into the disease.
In fiscal year 2017 alone, the National Cancer Institute (part of the National Institutes of Health) funded 876 studies into prostate cancer, while the Prostate Cancer Foundation reports that nearly 1,000 clinical trials are exploring treatments and treatment strategies in the U.S. Some of that research will lead to improvements in prevention, detection and treatment. In fact, prostate cancer deaths have been cut in half since 1993, when the Prostate Cancer Foundation was founded. The five-year survival rate now stands at 99%.
Yet prostate cancer is still the second-deadliest cancer among American men (after lung cancer). “There’s a misperception that this is a disease of old men that no one dies of,” says Dr. Jonathan W. Simons, president and CEO of the Prostate Cancer Foundation. “That’s wrong; a man still dies every twenty-one minutes around the clock from prostate cancer.”
Since September is National Prostate Cancer Awareness Month, this is a great time to review recent developments in prevention, diagnosis and treatment.
A Prostate Cancer Primer
Prostate cancer occurs when cells in the prostate, a small gland below the bladder involved in the production of sperm, begin to grow abnormally.
The first sign of the disease is often an elevated prostate-specific antigen (PSA) count in a blood test. Diagnosis and staging are confirmed through a digital rectal exam (DRE) and tissue biopsies, while genetic testing can help determine the cancer’s aggressiveness, an important factor in weighing treatment options.
"A man still dies every twenty-one minutes around the clock from prostate cancer."
Those options include active surveillance, surgery, chemotherapy, radiation therapy and hormone therapy, each of which comes with its own set of risks and benefits. For example, surgery and radiation can affect urinary, bowel and sexual function, which is one reason active surveillance is preferable for slow-growing, localized prostate cancer.
Family History and Genetics
Until recently, doctors assumed that the key risk factors for prostate cancer were age, a family history of prostate cancer and being of African-American ancestry. Today, however, researchers like Dr. Heather Cheng are looking at family history more broadly.
An associate professor of medical oncology at the University of Washington School of Medicine, Cheng says there are proven genetic links between prostate cancer in men and breast, ovarian and pancreatic cancer in their female relatives.
“If there is an inherited cancer risk, that risk may manifest itself in female relatives differently than in male relatives,” Cheng says.
The genetic links work both ways. When sharing their family history with their doctors, men should include information about female relatives — on both sides of the family — who have had cancer. And men who are diagnosed with metastatic prostate cancer should undergo genetic testing, as should their siblings and children if a mutation is discovered.
“That doesn’t mean a person will definitely get cancer, but it may increase their risk,” Cheng says. “It also provides information for them to use that risk knowledge to be proactive.”
Family history can also help inform a patient’s decision about whether to have a PSA test. That test is no longer routinely recommended due to the potential for overtreatment, but Cheng says it becomes more important if a man has a known mutation or if there’s a family history of early breast and ovarian cancer.
“The most inherited cancer of a hundred and eighty seven human cancers is, in fact, prostate cancer; that’s been discovered in the last two years,” says Jonathan Simons of the Prostate Cancer Foundation. “What’s kind of radical is that every urologist should be a genetic counselor.”
Diet and Exercise
While an apple a day won’t necessarily keep the doctor away, eating tomatoes, guava, watermelon, pink grapefruit, tree nuts, eggplant, spinach and beets may well keep prostate cancer at bay, according to Dr. William W. Li., author of Eat to Beat Disease: The New Science of How Your Body Can Heal Itself.
“Numerous studies have shown that certain foods contain natural chemicals that inhibit tumor angiogenesis (the growth of new blood vessels),” Li explains. “This means eating those foods can starve the cancer by cutting off the tumor blood supply.” For example, a National Cancer Institute study of nearly 50,000 men found that those who ate more cooked tomatoes, which are rich in lycopene, had a 28% lower risk of developing prostate cancer.
In fact, “Prostate cancer is the most sensitive cancer to a change in diet in terms of surviving longer,” says Simons.
Exercise — even brisk walking — plays a role as well. “Exercise improves immunity, which is important for preventing cancer,” Li says. “It also helps the body fight tumor angiogenesis, which can prevent or slow cancer growth. Exercise also improves the cardiovascular system, brain function and muscle strength — all important factors for healthy aging.”
Technology and Treatment
The Prostate Cancer Foundation estimates that 175,000 men in the United States will be diagnosed with prostate cancer this year. Fortunately, recent advances are making it easier to detect and treat the disease, according to Dr. Sven Wenske, who practices urology at the Columbia University Irving Medical Center in New York City.
One important advance is the development of magnetic resonance imaging (MRI) fusion technology, in which MRI and ultrasound images are combined to give physicians a better picture of the prostate.
“Instead of just taking random (biopsy) samples under ultrasound guidance only from the left and the right lobe (parts of the prostate), we basically target specific areas that the MRI shows us to be abnormal,” Wenske says. “This is a much more specific and much more accurate way to diagnose prostate cancer.” What’s more, the technology can also be used during active surveillance to determine the need for additional biopsies.
More Tools in the Toolbox
In cases of metastatic prostate cancer, doctors now have more tools in their toolboxes, thanks to second-generation anti-androgens. Androgens are male hormones — including testosterone, which helps cancer grow. The new anti-androgens include apalutamide, enzalutamide and darolutamide, the latter of which was approved by the Food and Drug Administration in July 2019.
“These drugs really help to keep the cancer under control,” Wenske says.
More drug approvals are on the horizon. In fact, Simons recommends patients keep up with the latest news on the Prostate Cancer Foundation’s website because some clinicians may not be aware of the latest developments.
Also on the horizon are increasingly targeted therapies that are no undergoing clinical trials. For example, researchers are testing radioactive molecules that can move through the bloodstream, searching for and destroying prostate cancer cells. These agents target prostate membrane-specific antigen, or PSMA, a protein on the surface of the cells.
Genetics may play a role here as well; a study from The Institute of Cancer Research has shown that genetic testing could help identify patients who would respond well to this therapy.
Prostate Cancer and Dementia
Although much of the recent news about treatments for prostate cancer has been positive, a study published in July 2019 offered a stark reminder that standard treatments can have serious side effects.
Researchers at the University of Pennsylvania's Perelman School of Medicine did a retrospective study of 154,000 prostate cancer patients and found that androgen-deprivation therapy (ADT; also called hormone therapy) was associated with a heightened risk of developing dementia and Alzheimer’s disease. Specifically, 13% of patients who received ADT developed Alzheimer’s disease, compared with 9% of patients who didn’t receive the therapy, while 22% of ADT patients developed some form of dementia, versus 16% of non-ADT patients.
Those results didn’t surprise Wenske, who has seen anecdotal evidence among his own patients. Unfortunately, he says, “that’s the only way at this time to really suppress the cancer. If they don’t do that treatment, they have a risk for progression. There’s not a lot of wiggle room between choices.”
That’s why it’s reassuring that the National Cancer Institute, the Prostate Cancer Foundation and other groups continue pouring money into research and clinical trials. Perhaps one day, negative side effects — and prostate cancer itself — will become distant memories.
The Prostate Cancer Foundation offers several free resources on its website, including the “Prostate Cancer Patient Guide” (updated for 2019) and “The Science of Living Well, Beyond Cancer” (published in August 2019), which explores the relationship between lifestyle choices and cancer.