Plaque-Type Psoriasis Treated with Calcipotriene Plus Betamethasone Dipropionate Aerosol Foam: A Prospective Study on Clinical and Dermoscopic Predictor Factors in Response Achievement and Retention

Introduction: Little information on possible local factors that can influence the achievement and retention of response of plaque-type psoriasis to calcipotriene plus betamethasone dipropionate aerosol foam is available. The aim of this study was to assess possible correlations between baseline clinical/dermoscopic features of psoriatic plaques and therapeutic response, and between residual dermoscopic findings in clinically improved/healed lesions and post-treatment relapse. Methods: For each target lesion, we calculated the local psoriasis severity index and assessed dermoscopic findings at baseline and at the end of a 4-week treatment, correlating the therapeutic outcome with the initial clinical and dermoscopic features. The lesions were also followed for a 4-week post-treatment period, and possible associations between relapse and (1) baseline clinical/dermoscopic features and (2) dermoscopic findings detected at the end of the treatment were assessed. Results: A total of 105 lesions from 35 patients were included in the analysis. After 4 weeks of therapy, 13 lesions showed no/limited improvement, while partial and optimal response were observed in 51 and 41 plaques, respectively. Poor outcomes were correlated with both legs localization and degree of lesion infiltration at baseline. Similarly, presence of globular vessels at baseline dermoscopy was more commonly associated with no/limited response and lesions on the legs, particularly those showing resistance to treatment. A correlation was also found between dotted vessels on the baseline dermoscopic examination and good outcomes (partial/optimal response). After a 4-week post-treatment follow-up, 58.7% of the lesions achieving improvement at the end of the therapy showed relapse, with a correlation between recurrence and vessel persistence on dermoscopy at the end of the therapy. Conclusion: Clinical response of plaque-type psoriasis to calcipotriol/betamethasone dipropionate spray foam may be adversely affected by the degree of infiltration of lesions at baseline and by legs localization, and the presence of globular vessels at the baseline dermoscopic assessment is related to poor outcomes. A significant post-treatment relapse rate was observed, and persistence of vascular changes on dermoscopy seems to play a role in promoting disease recurrence.