Adipose tissue regeneration in
breast cancer patients without additional
growth factors or adipose-tissue-derived stromal cells is desirable because of the possibility of recurrence and
metastasis. We report that a
poly-L-lactic acid (PLLA) mesh implant containing a
collagen sponge (CS) maintained the internal space in vivo for up to 12 months and substituted for adipose tissue. We developed a PLLA
capsule that maintained the internal space longer than that of PLLA mesh and compared adipose tissue formation at 12 and 24 months after implantation between the PLLA mesh with CS implant and the PLLA
capsule implant with or without CS in a rabbit model. After 12 months, all implants maintained the internal space, and the adipose tissue that formed in all implant groups was larger than that in the control group. At 24 months, PLLA mesh maintained the internal space just as well as that at 12 months, while the PLLA
capsule collapsed and accumulated a large number of macrophages. The formed adipose tissue in the PLLA mesh group was maintained up to 24 months; however, those in two PLLA
capsule groups decreased and showed no difference from the control group. In conclusion, the internal space of the PLLA mesh implant with CS was substituted for adipose tissue at 12 months and sustained the formed adipose tissue after 24 months. The PLLA mesh implant containing CS is a desirable
bioabsorbable implant that can be replaced by autologous adipose tissue after implantation in vivo without using any
growth factors or cells.