Comparing the efficacy of plasma exeresis and cryotherapy for the treatment of seborrheic keratosis: A randomized controlled trial

BACKGROUND: Seborrheic keratoses (SK) is a benign epithelial skin tumor and plasma exeresis is a new technique. AIMS: To compare the efficacy and safety of plasma exeresis and cryotherapy for treating SK. METHODS: This study is a randomized controlled trial (RCT). One side of each patient was randomly treated with plasma exeresis (peak‐to‐peak voltage of 3.44 kV and a frequency of 62.5 kHz) and the other side with cryotherapy. RESULTS: Thirty‐five males were enrolled. At week 3, 37.1 % (N = 13) of lesions treated by plasma exeresis were clear, which was higher than those treated by cryotherapy 17.1% (N = 6). However, this difference was not significant (p‐value: 0.06). At week 6, 16 (57.1 %) out of 28 remaining lesions, treated by plasma exeresis were clear, which was significantly higher (p‐value: 0.005) than those completely cleared by cryotherapy in 6 out of 29 remaining lesions (20.7%). The mean physician assessment scale score was significantly reduced in both groups in the second follow‐up (plasma group first follow‐up 0.91 ± 0.89 vs. second follow‐up 0.5 ± 0.64 and p‐value: 0.0031; cryo group first follow‐up 1.4 ± 0.84 vs. second follow‐up 1.1 ± 0.72 and p‐value: 0.0002). Regarding side effects, no significant difference was seen (p = 0.438). The most common complications in the plasma and cryotherapy groups were erythema (10/19, 52.63%) and hypo pigmentation (5/13, 38.46%). CONCLUSIONS: Both cryotherapy and plasma exeresis are effective. We observed a significantly higher cleared lesions treated with plasma exeresis in 6 weeks and after two sessions.