Current state of tissue engineering for repair of congenital hypospadias

In the past several decades, numerous advances in the field of tissue engineering have been made towards the management of hypospadias and associated urethral defects. Reliable products for clinical use still remain elusive, however. Hypospadias affects approximately 0.3% of live births with current practice favoring early repair. With the advances in surgical approaches to hypospadias repair, such as the tubularized-incised plate, mid-shaft and distal variants rarely require supplemental tissue. In more proximal and perineal urethral defects, and especially in the case of the hypospadias cripple, however, patients may lack adequate, healthy local tissue for definitive repair. Ongoing research into the use of acellular matrix grafts and cell-seeded matrix grafts have produced promising results in animal models. Unfortunately, these grafts can be plagued by graft loss, graft contracture, stricture formation, and fistulization. Extensive additional research remains to evaluate the long-term biosafety and efficacy of these materials and to determine a reproducible and costeffective means for their use in clinical practice.