<qa>  What is a soft tissue graft formed by decellularization?This is a prospective study, where patients undergoing breast reconstruction surgery using acellular dermal matrix ADM with expander use in first phase of reconstruction will be included. The permanent breast implants will be implanted approximately half year during second surgery. Acellular dermal matrix is a soft tissue graft that is formed by decellularization, however with intact extracellular dermal matrix. Such structure is able to re-create adequate skeleton for host cells with subsequent incorporation and revascularization. The safety and appropriateness of such ADM in breast reconstruction surgery will be analyzed. 