Follicular mucinosis successfully treated by photodynamic therapy: Two case reports

•Two follicular mucinosis patients were successfully treated with photodynamic therapy.•The efficacy of a patient with mycosis fungoides-associated follicular mucinosis was evaluated by pathological changes for the first time.•The expression of CD103 was found to decline when the lesions improved.•This study may provide a more objective basis for the therapeutic effect of follicular mucinosis.