BackgroundChanges in the areola size after reconstruction of the nipple-areola complex (NAC) following mastectomy and breast reconstruction with a silicon implant in primary breast cancer patients have not been well examined. This study aimed to investigate time-dependent changes in the size of the donor and graft NACs and to assess clinical factors influencing these changes.MethodsFifty-eight consecutive patients who underwent nipple-areola reconstruction were retrospectively evaluated. Nipple-areola diameter was measured immediately after the NAC reconstruction and at each follow-up visit for at least 36 months.ResultsThe donor NAC constituted 81 % of the graft NAC at the time of operation. The size of the donor NAC gradually increased by up to 36.8 % after the operation. The size of the graft NAC showed a decrease by 4.5 % at 7 months, followed by recovery to the initial value. The ratio of the donor site size to the graft site size was increased at month 1 and then showed a gradual decrease to 1.08 at 36 months. A history of mastopexy or reduction for the donor site was independent factors associated with changes in the NAC size.ConclusionsTo achieve symmetry, the diameter of the donor NAC immediately after the reconstruction should be at least 20 % smaller than that of the graft NAC, especially for patients without a history of additional operations.