By J. Peter Rubin, MD Chief of Plastic Surgery University of Pittsburgh
Stem cells have captured the imagination of the American public and offer great promise for new therapies in many areas of medical practice. In particular, the efforts to establish better therapies for breast reconstruction will improve the lives of cancer survivors and help restore a woman’s body to the natural form after cancer surgery.
The new therapy that Suzanne Somers underwent is a minimally invasive method of restoring breast volume using fat moved from another part of the body. The field of fat grafting in plastic surgery has been in existence for several decades in the United States. The actual technique dates back over 100 years in medical literature, but a rise in popularity of fat grafting has been seen in recent years due to the development of specialized surgical instruments that are now widely available.
The biggest problem encountered with fat grafting is that fat can lose volume or be absorbed by the body over time, leaving less of an affect from the original treatment. In this therapy, stem cells separated from a patient’s own fat tissue are mixed back with the fat graft to help enhance the healing of the fat graft.
While this technology is promising, we must not forget that this is an experimental treatment and should only be done as part of an approved clinical trial. There are several concerns that must be addressed and carefully studied before this therapy would be available for general use. These include the following:
1. The first concern is whether the stem cells that are used to enhance the fat grafting will stimulate the growth of breast cancer cells. Stem cells are useful in this situation because they act like little factories producing chemicals that can stimulate the healing process. In patients who have had radiation and scar tissue, this can potentially improve the blood supply to the tissues and give a better result from the fat-grafting procedure with increased retention of the volume of tissue that is placed. However, the same beneficial effect could also potentially stimulate the growth of cancer cells that are left behind the same area.
Studies show that stem cells, when grown with cancer cells in a culture dish, can increase the growth of the cancer cells. Those studies, however, do have many limitations in that they are only performed in a culture dish and that the cancer cells used are very fast growing to begin with. There are some animal experiments that suggest similar results.
In work done by our group at the University of Pittsburgh, we tested the effect of stem cells on cancer cells that have been separated into two groups: fast-growing cells or dormant cancer cells. This better simulates the situation that we see in breast cancer patients in which there may be some cancer cells in other areas of the breast that are dormant. Our studies showed that the dormant cancer cells are not activated to grow by the stem cells. This leads to the next question that we need answer about this therapy: When is it safe to use this therapy?
2. Given the possibility that stem cells could stimulate the growth of cancer cells, these treatments may be best used in patients who are clinically free of the cancer. Therefore, an important question to answer is about the timing of this treatment relative to the breast cancer surgery. How long must we wait before administering this therapy to confirm that patients are free of disease? This can only be answered through careful clinical studies in a large number of patients who are followed over years.
3. Another concern is whether this therapy will interfere with breast cancer screenings. Any surgery to the breast will cause changes on mammography. It is very important for patients to tell mammographers about any procedures they have had so the radiologist can best interpret the results. There has been concern that injecting fat into the breast can result in changes that look dangerous in mammogram results because the fat may produce scaring and small calcifications in the breast. This could lead to a high rate of biopsies that are not needed. However, a study conducted by our research group at the University of Pittsburgh demonstrates that the changes are no more severe than those we see after breast reduction, a commonly performed breast operation. More studies need to be performed to confirm this finding, but it appears that while any surgery will cause changes on mammogram and potentially interfere with cancer screening, this procedure is no worse.
4. There are other general concerns with any fat grafting procedure that need to be considered as well. This includes the problem that the fat can form hard lumps, known as fat necrosis, and represents the fat forming scar tissue instead of remaining soft to the touch. Additionally, even with the use of stem cells to help with healing, a portion of the fat may be absorbed by the body and the desired effect of the treatment (increased volume in the breast) may not be seen.
Overall, this is exciting technology and represents a potential future therapy for breast reconstruction. It is interesting to note that our standard operations for breast reconstruction, including the use of implants and large procedures to move skin and fat from the belly to the chest, were developed in the 1970s and 1980s. It is certainly time for new advances in this field.
It is also interesting to note that the technology described here can be used across the entire body for both reconstructive and cosmetic purposes. For example, we are conducting a special clinical trial at the University of Pittsburgh to help our wounded military personnel and others with facial injuries using this same technology. This is a very important study because up to 26% of our wounded warriors have facial injuries. The study that we are conducting is open to both military personnel and civilians anywhere in the United States with visible injuries to the face or skull. Additionally, all of the costs of treatment, including travel for the patients, are covered under the program funded by the United States Department of Defense. Suzanne Somers herself spoke about the importance of supporting new therapies for our wounded warriors during her appearance on The Dr. Oz Show.