The risk of skin metastases depends largely on the characteristics of tumour cells, which is similar among different ethnic groups. In terms of prognosis, a subset of breast cancer patients has superior prognosis, even among breast cancer patients with stage IV disease. Physicians should consider this finding in clinical situations to avoid possible misinformation about the prognosis of the disease.

Our study provides in vitro evidence demonstrating that direct interaction between FK506 and KCs creates a favourable milieu for MC growth and migration. Furthermore, our findings provide a possible mechanism explaining how tacrolimus ointment induces repigmentation in patients with vitiligo.