POSTN and systemic sclerosis: The uninvolved skin of three lc-SSc patients, however, showed a mild periostin expression on IHC, and all three lc-SSc patients (ACA+ and untreated due to a limited cutaneous and not complicated disease) with mild periostin IHC expression on uninvolved skin presented a significant skin progression with >30% increase in the mRSS during the follow-up.