On a hectic day this week, I found a voice mail message from a sweet-sounding woman in Michigan. She wanted to know if the Herald-Tribune had ever published anything about a Sarasota doctor who is promising to cure her husband's COPD with stem cell replacement therapy.
She loves her husband very much, she said, and was willing to spend $7,700 she can't afford, plus travel expenses, if this doctor could help her husband. COPD -- chronic pulmonary obstructive disorder -- is a terrible disease that makes breathing a constant chore. Quitting smoking helps, but there is no cure. I could understand why her husband might pin his hopes on any plausible story about a new scientific breakthrough that could ease his troubles.
This newspaper has not explored the claims of this particular doctor, and doing so will take some time and care. But this lady needed some guidance right away, so I gave her some information that would help her and her husband make a decision. I told her the doctor in question had no medical license in Florida -- not a good sign. And I told her that while reputable doctors are very excited about the potential of stem cell therapy, very few treatments are currently tested and approved. COPD is not among the disorders where stem cell treatment is considered valid.
Then I directed her to the website of the International Society for Stem Cell Research, which has this really clear and helpful list of "Top 10 Stem Cell Treatment Facts." I've condensed it a little here, but the words are from the website:
1. There are different types of stem cells—each with their own purpose. There are many different types of stem cells that come from different places in the body or are formed at different times in our lives. Our bodies use different types of tissue-specific stem cells to fit a particular purpose. Tissue-specific stem cells are limited in their potential and largely make the cell types found in the tissue from which they are derived. It is unlikely that a single cell type could be used to treat a multitude of unrelated diseases that involve different tissues or organs. Be wary of clinics that offer treatments with stem cells that originate from a part of the body that is different from the part being treated.
2. A single stem cell treatment will not work on a multitude of unrelated diseases or conditions. It is unlikely that a single type of stem cell treatment can treat multiple unrelated conditions, such as diabetes and Parkinson’s disease. The underlying causes are very different and different cell types would need to be replaced to treat each condition. It is critical that the cell type used as a treatment be appropriate to the specific disease or condition. Embryonic stem cells may one day be used to generate treatments for a range of human diseases. However, embryonic stem cells themselves cannot directly be used for therapies as they would likely cause tumors and are unlikely to become the cells needed to regenerate a tissue on their own.
3. Currently, there are very few widely accepted stem cell therapies. The range of diseases where stem cell treatments have been shown to be beneficial in responsibly conducted clinical trials is still extremely restricted. The best defined and most extensively used is blood stem cell transplantation to treat diseases and conditions of the blood and immune system, or to restore the blood system after treatments for specific cancers. Some bone, skin and corneal diseases or injuries can be treated with grafting of tissue that depends upon stem cells from these organs. These therapies are also generally accepted as safe and effective by the medical community.
4. Just because people say stem cells helped them doesn’t mean they did. There are three main reasons why a person might feel better that are unrelated to the actual stem cell treatment: the ‘placebo effect’, accompanying treatments, and natural fluctuations of the disease or condition. The intense desire or belief that a treatment will work can cause a person to feel like it has and to even experience positive physical changes, such as improved movement or less pain. This phenomenon is called the placebo effect. Even having a positive conversation with a doctor can cause a person to feel improvement. Likewise, other techniques offered along with stem cell treatment—such as changes to diet, relaxation, physical therapy, medication, etc.—may make a person feel better in a way that is unrelated to the stem cells. Also, the severity of symptoms of many conditions can change over time. Be wary of clinics that measure or advertise their results primarily through patient testimonials.
5. A large part of why it takes time to develop new therapies is that science itself is a long and difficult process. Science, in general, is a long and involved process. Understanding what goes wrong in disease or injury and how to fix it takes time. New ideas have to be tested first in a research laboratory, and many times the new ideas don’t work. Once therapies are tested in humans, ensuring patient safety becomes a critical issue and this means starting with very few people until the safety and side effects are better understood.
6. To be used in treatments, stem cells will have to be instructed to behave in specific ways. Bone marrow transplantation is typically successful because we are asking the cells to do exactly what they were designed to do, make more blood. For other conditions, we may want the cells to behave in ways that are different from how they would ordinarily work in the body. One of the greatest barriers to the development of successful stem cell therapies is to get the cells to behave in the desired way. Be wary of claims that stem cells will somehow just know where to go and what to do to treat a specific condition.
7. Just because stem cells came from your body doesn’t mean they are safe. Every medical procedure has risks. While you are unlikely to have an immune response to your own cells, the procedures used to acquire, grow and deliver them are potentially risky. As soon as the cells leave your body they may be subjected to a number of manipulations that could change the characteristics of the cells. If they are grown in culture (a process called expansion), the cells may lose the normal mechanisms that control growth or may lose the ability to specialize into the cell types you need. The cells may become contaminated with bacteria, viruses or other pathogens that could cause disease. The procedure to either remove or inject the cells also carries risk, from introducing an infection to damaging the tissue into which they are injected.
8. There is something to lose by trying an unproven treatment. Some of the conditions that clinics claim are treatable with stem cells are considered incurable by other means. It is easy to understand why people might feel they have nothing to lose from trying something even if it is unproven. However, there are very real risks of developing complications, both immediate and long-term, while the chance of experiencing a benefit is likely very low. In one publicized case, a young boy developed brain tumors as a result of a stem cell treatment.
9. An experimental treatment offered for sale is not the same as a clinical trial. The fact that a procedure is experimental does not automatically mean that it is part of a research study or clinical trial. A responsible clinical trial can be characterized by a number of key features. There is preclinical data supporting that the treatment being tested is likely to be safe and effective. Before starting, there is oversight by an independent group, and in many countries the trial is assessed and approved by a national regulatory agency. The study itself is designed to answer specific questions about a new treatment or a new way of using current treatments, often with a control group to which the group of people receiving the new treatment is compared. Typically, the cost of the new treatment and trial monitoring is defrayed by the company developing the treatment or by government funding. Beware of expensive treatments that have not passed successfully through clinical trials.
10. Stem cell science is constantly moving forward. Stem cell science is extraordinarily promising. There have been great advances in treating diseases and conditions of the blood system using blood-forming stem cells, and these show us just how powerful stem cell therapies can be. Scientists all over the world are researching ways to harness stem cells and use them to learn more about, to diagnose, and to treat various diseases and conditions. Every day scientists are working on new ways to shape and control different types of stem cells in ways that are bringing us closer to developing new treatments. Many potential treatments are currently being tested in animal models and some have already been brought to clinical trials. We are tremendously optimistic that stem cell therapies will someday be available to treat a wide range of human diseases and conditions.