Treating seborrheic keratosis (SK) with 20 MHz of high intensity focused ultrasound (HIFU) is a safe and effective treatment modality, according to research published in Clinical, Cosmetic, and Investigational Dermatology.
For the open-label study, researchers offered HIFU to patients with SK as an alternative to cryosurgery or surgical methods. The investigators treated 54 SK lesions across 11 study participants. The patients included 8 women and 3 men with an average age of 51.5±13.2 years. SK lesions were treated on different anatomical locations of the body, including the front and back trunk (52%), the neck and face (33%), and the arms and legs (15%).
During HIFU, the pain level was reportedly “acceptable” for all study participants. The procedure did not require discontinuation at any moment due to patients’ pain sensations. If pain occurred, patients reported that it was temporary and lasted during exposure to ultrasound. It waned after the procedure. On a 0- to 10-point Visual Analog Scale for pain severity, most patients scored their pain at approximately 2, and other patients reported up to a pain score of 4. Those who did experience painful sensations compared the pain to “pin pricks.”
Researchers recorded verbal reports on study participants’ healing process. Most often, participants reported that around 7 to 14 days after treatment, they saw the exfoliation or separation of a thin wound crust and pink rebuilt epidermis. There were no complaints of pain or discomfort during the healing period.
From the 54 SK lesions treated, 18 (33.4%) did not produce observable side effects. In 26 of the treated lesions (48.1%) there was superficial telangiectasia and capillary blood network in the treatment area. Six lesions (11.1%) had observable scarring, but the scarring was mild and not related to bacterial infections. However, researchers could not determine if the scarring and fibrotic tissue changes were caused by the HIFU treatment or caused by preexisting changes in the dermis due to the SK lesion. Participants described the side effects as mild.
Of the 54 SK lesions treated with HIFU, 52 (96.3%) indicated a positive response to the treatment, 37 (68.5%) met the criteria for “complete response,” and 15 (27.8%) were “partial response.” There were 2 cases (3.7%) that did not respond to the treatment at all, and so those cases were defined as “stable condition.” There were no reports of worsening of the condition and therefore no “progressive condition” classification.
Limitations included a small study population, a lack of blinded scoring, and no randomized comparisons with comparative methods.
Based on the study data, the researchers concluded that, “20 MHz high intensity focused ultrasound is considered a new and very broadly applicable treatment modality for [SK]. In this study, a very good safety profile and high efficacy has been demonstrated.”
Calik J, Migdal M, Zawada T, Bove T. Treatment of seborrheic keratosis by high frequency focused ultrasound – an early experience with 11 consecutive cases. Clinical, Cosmetic, and Investigational Dermatology. Published online January 28, 2022. doi:10.2147/CCID.S348106.