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The SAGE Encyclopedia of Stem Cell Research


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      Seong, J. M., B. C. Kim, J. H. Park, et al. “Stem Cells in Bone Tissue Engineering.” Biomedical Materials, v.5/06 (2010).

      Shiffman, M. A., and S. Mirrafati. “Fat Transfer Techniques: The Effect of Harvest and Transfer Methods on Adipocyte Viability and Review of the Literature.” Dermatologic Surgery, v.27 (2001).

      Sterodimas, A., J. de Faria, B. Nicaretta, et al. “Tissue Engineering With Adipose-Derived Stem Cells (ADSCs): Current and Future Applications.” Journal of Plastic, Reconstructive and Aesthetic Surgery, v.63 (2010).

      Yoshimura, K., et al. “Cell-Assisted Lipotransfer for Facial Lipoatrophy: Efficacy of Clinical Use of Adipose-Derived Cells.” Dermatologic Surgery, v.34 (2006).

      Yoshimura, K., et al. “Cell-Assisted Lipotransfer for Cosmetic Breast Augmentation: Supportive Use of Adipose-Derived Stem/Stromal Cells.” Aesthetic Plastic Surgery, v.32/1 (2008).

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      Breast: Existing or Potential Regenerative Medicine Strategies

      Breast: Existing or Potential Regenerative Medicine Strategies

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      Breast: Existing or Potential Regenerative Medicine Strategies

      One aspect of regenerative medicine strategies of the breast involves treatment of breast cancer patients. Treatment of breast cancer depends on the kind of breast cancer and how far it has spread. Breast cancer treatment usually involves surgical removal of the tumor itself along with all or part of the surrounding normal breast tissue. After the operation, the breast is usually treated with radiation, which can alter the architecture of the breast. Methods of reconstruction include breast prosthetics or autologous tissue flaps. The reconstruction can be performed immediately at the time of mastectomy or on a delayed basis.

      Subpectoral tissue expanders prepare the breast for implantation with saline or silicone. Reconstruction with implants is common, as the recovery is rapid and there is no donor site morbidity. However, implants can have several complications. Plastic surgeons are able to reconstruct the breast using autologous tissue flaps such as the latissimus dorsi, transverse rectus abdominus myocutaneous (TRAM) flap, and various perforator flaps. These terms represent abdominal tissue and vascular supplies used to reconstruct the breast. Perforator flaps minimize donor site morbidity through the preservation of muscle.

      The implants are linked with the problems of any large foreign mass in the body. They are particularly problematic after radiation treatment. Stem cell treatment of the breast poses the advantage of creating a natural regrowth of fat tissue within the breast, which will give it a soft, natural appearance. Using body fat stored in the woman’s hips or thighs, the fat can recreate a natural breast.

      Breast Reconstruction With Fat Graft and Plasma

      Fat grafting, also known as autologous fat transfer, is a reconstructive technique that involves taking fat from the patient’s body via liposuction, processing it, and then injecting the liquefied fat into another area of the body. An alternative form of fat grafting, called lipofilling, has been used for a number of years to treat minor shape, contour, or positioning issues of the reconstructed breast. Present research surrounding lipofilling involves reconstructing an entire breast using fat. One considerable limitation to this strategy is the variability in results due to resorption. Over time, this results in a variable reduction in volume. Some clinicians utilize a Brava device, which is an external tissue expander. In this fat grafting technique, the Brava device is worn for several weeks prior to and after the fat grafting. The Brava device is a bra shaped with plastic cones for cups. The cones put suction on the breast area to expand the tissue, creating a matrix for fat to reside and preventing deformation and a loss of volume.

      Fat grafting is advantageous in that patients are able to use their own native tissue instead of an implant. The fat is often removed from an area where the patient does not want fat, such as the buttocks or thigh. The treatment involves local anesthetic. The recovery period for fat graft patients is much shorter and less disruptive than other techniques. Many women report that a fat-graft reconstructed breast provides a natural, soft feel similar to an unreconstructed breast. Disadvantages for fat grafting treatment include the prolonged use of the Brava device, which can provide discomfort for the patient. The injected fat may be reabsorbed by the body over time. Since some fat cells can stimulate cell growth, some clinicians are concerned that fat injected into the breast may cause dormant breast cancer cells to grow. Research has not been done to address these concerns. Lastly, some of the fat transplanted into the breast tissue area may die off, resulting in necrosis and a number of undesired side effects.

      Regenerative Medicine Strategies to Treat Breasts of Burn Victims

      Using regenerative medicine strategies to treat burned breast poses several clinical problems. Scarring of the breast can adversely affect the development, contour, and positioning of the breast as well as the cosmetic appearance of the surface of the skin. Traditional treatment involves contracture release and thick split-thickness skin grafting techniques. However, an alternative approach employs dermal regeneration templates for breast reconstruction. One study involved patients who had suffered anterior chest wall burns during childhood. After scar contractures were removed, unmeshed Integra was applied to the wound. Integra is a collagen glycosaminoglycan dermal matrix covered with an outer silicone layer. One month after treatment, naturally-formed collagen fibers were observed in the dermal regeneration template.

      By one year, the host collagen had completely replaced the Integra matrix. The elastic fibers were evident throughout the neodermis of the patients. All patients had consistent improvements in breast contour and shape. Clinically relevant recontracture of the graft site did not occur postoperatively. The patients were very satisfied with the outcome of the reconstructive surgery. Grafting with Integra provided an effective and well-tolerated alternative to thick-split thickness grafting for breast reconstruction. Now the biocompatible material is available in unlimited quantity. The special biomaterial can be molded to the particular wound site in the patient without a need for a deep donor site wound or potential for infection, permanent pigment changes, or scarring.

      Adipose Tissue-Derived Cells Regenerative Medicine Strategies for the Breast

      Ideally, breast reconstruction is performed with the patient’s own fat and skin. Most current techniques for autogenous reconstruction make use of myocutaneous flaps. Skin and fat can also be transferred from the lower abdomen without sacrificing muscle. These flaps are based on one, two, or three perforators of the deep inferior epigastric vessels. The technique has all the direct advantages of the free TRAM flap with decreased possibility of ventral hernia or muscle weakness.

      Existing Breast Reconstruction Strategies

      Tissue expansion. Breast reconstruction is commonly performed using a temporary tissue expander, which expands the breast skin and chest muscle. A breast tissue expansion device is an inflatable breast implant designed to expand and stretch the skin and muscle to make additional space for a permanent breast implant. A few months after inserting the expander, it is removed and the patient receives either microvascular flap reconstruction or a permanent breast implant.

      Latissimus dorsi myocutaneous flap surgery. The latissimus dorsi myocutaneous flap (LDMF) is considered one of the more reliable and versatile flaps used in breast reconstruction. LDMF has several advantages, including the availability of a large volume of tissue. The long vascular pedicle offers a superior range for pedicled flaps. The high caliber pedicle makes free flap vascular anastomoses technically more feasible, even in patients who have significant atherosclerotic disease. There is minimal donor site morbidity. The LDMF is used to provide a sensate reconstruction when it is transferred