What is cancer? In the simplest of terms, cancer refers to cells in the human body growing out of control. The body, unable to regulate these cells, eventually succumbs to the chaos associated with uncontrolled growth. Man has long struggled with this disease; physicians from 3000 BC report burning the external manifestations of cancer with a “fire drill” and despairingly wrote that there was no successful treatment.
Treatments Numerous therapies have been developed since, but many were pitched by grifters and pseudo-scientists looking to capitalize on the hopeful desperation of victims and their families. Even the best scientists developed theories that seem outlandish today. Hippocrates declared that the body “humors,” blood, phlegm and yellow-and-black bile, needed to be in “balance.” This theory persisted for more than 1,300 years! Later claims still seem equally far-fetched, but were advanced by some of the most respected minds of the times.
Until recently, the accepted treatments mainly involved surgery, chemotherapy and radiation. Surgery attempts to remove the faulty deadly tissues, whereas chemotherapy and radiation destroy the engines in these rapidly growing cells, thereby preferentially killing cancer cells. Through decades of research, variations of these treatments have become more sophisticated, more precise and more successful.
For example, patients with testicular cancer can actually be cured with these existing treatments. Collateral damage and side effects can be minimized with successful cancer treatment, as well. Patients cured surgically for prostate cancer can hope for recovery of urinary and sexual function, especially if a surgeon experienced and skilled in robotic techniques performs the surgery.
Immunotherapy The notion of using the immune system to fight the body’s cancer is not new. The value of proper nutrition and exercise has been advocated for years as a way to keep the body and its immune system primed for such struggles. However, cancer can often elude even the stoutest defenses if the immune system doesn’t know what to seek.
Science has developed biologics such as cytokines and interferons, which serve as stimulants or a “volume knob” for the immune system. These treatments are used to treat patients with advanced kidney cancer. However, an immune system that has its volume “turned up” with no directed target puts the entire body at risk, and the increased stress to the system often makes patients very sick.
Immunotherapy was given a boost when scientists discovered how to mass-make antibodies in the 1970s. As understanding of various cancers progressed, studies were launched to see if the antibodies could be used to more precisely recognize antigens present on the cancer cells.
Antigen recognition led to breakthroughs in the imaging and treatment of different cancers. The first therapeutic monoclonal antibodies, Rituxan and Herceptin, were approved during the late 1990s for the treatment of lymphoma and breast cancer, respectively. Monoclonal antibodies are like soldiers deployed to recognize and defeat a specific enemy. They now have a defined role against many cancers and are undergoing study in the treatment of other cancers.
Of course, relying on outside soldiers to fight cancer seems less ideal than triggering one’s own immune system to create an army of its own fighters. In 2009, scientists reported the first successful tuning of the immune system in a study showing that immunotherapy-treated lymphoma patients lived longer. In 2010, the Food and Drug Administration (FDA) approved Provenge as the first and only immunotherapy for the treatment of advanced prostate cancer.2
Provenge is an autologous (pronounced aw-tol-uh-guhs) treatment, which means that the immune cells activated to fight the prostate cancer come from the patient himself. Normally, once prostate cancer spreads to the bone, treatment focuses on castration or eliminating testosterone, which serves as fuel for this cancer. At a certain point, prostate cancer cells outwit castration and lead to the patient’s death. With Provenge, patients can call on their immune system to jump into battle once castration no longer works.
Treatment with Provenge
During the course of a month, patients receive three personalized doses of Provenge. To make each dose, blood is drawn and a machine collects a fraction of the immune cells present. These cells are then sent to a facility where they are stimulated and exposed to an antigen associated with prostate cancer. A few days later, the patient receives the personalized dose, now rich in activated T cells, trained and prepared to fight the prostate cancer cells.
Patients can live longer with Provenge. A clinical study showed a 22.5 percent reduction in the risk of death. Less than 1.5 percent of men had to stop treatment due to side effects, which were usually temporary chills, fatigue, nausea or fever associated with the infusion of the cells.3
Understanding and interpreting the success of treatment is slightly different than with surgery or castration, which can immediately drop blood levels of PSA – a marker associated with prostate cancer. Immunotherapy takes time to start working, and changes in PSA levels do not fully deduce the immediate success of the treatment.
Immunotherapy represents an exciting new frontier in the treatment of prostate cancer. History has shown that cancer treatments are ever evolving, but the change usually generates great success.
- Provenge is immunotherapy for the treatment of asymptomatic or minimally symptomatic patients with metastatic prostate cancer not responding to conventional castration therapy.
Naveen Kella, M.D., is the director of robotic surgery and a board-certified urologist at the Urology and Prostate Institute. For more information or to schedule a consultation with him, please contact the institute at 210-284-6640.