Wood LD, Stucki JK, Hollenbeak CS, Miller JJ. Effectiveness of Cryosurgery vs Curettage in the Treatment of Seborrheic Keratoses. JAMA Dermatol. 2013;149(1):108-109. doi:10.1001/2013.jamadermatol.275
Author Affiliations: Departments of Dermatology (Drs Wood and Miller) and Public Health Sciences (Dr Hollenbeak) and College of Medicine (Mr Stucki), Hershey Medical Center Penn State University, Hershey, Pennsylvania.
Seborrheic keratoses (SKs) are one of the most common types of skin lesions (prevalence, 69%-100% among adults older than 50 years).1 Although SKs are benign, patients with SKs frequently desire treatment for symptoms of itching and irritation or for cosmetic purposes. Seborrheic keratoses have been treated with varying efficacy by many techniques.2 Two effective options include cryosurgery and curettage.3- 5 Our objective was to determine comparative efficacy of cryosurgery and curettage in the treatment of SKs on the trunk and proximal extremities.
Twenty-five adults, aged 52 to 75 years, with diagnoses of SK were enrolled in our study. Treatment options were curettage or cryotherapy, based on coin-toss randomization. Lesions treated with curettage were injected with lidocaine, 1%, with epinephrine and buffer using a 30-gauge needle. A No. 15 scalpel was used to curette the lesions. Subjects were instructed to cover the wound with petrolatum and a bandage. Lesions treated with cryotherapy were treated using liquid nitrogen in a 1-cycle stutter technique to ensure that the freezing stayed within the confines of lesion and to ensure complete freezing for approximately 12 seconds.
For each participant, one SK lesion to be treated was identified on each side of the trunk or proximal extremities. When multiple SKs were present, 2 with similar characteristics (size and thickness) were selected.
Subject evaluations were obtained via questionnaire. Treatment sites were also evaluated based on texture and color variation by a blinded physician observer (L.D.W.) 6 weeks and more than 12 months after each intervention.
This study was approved by the Penn State Hershey institutional review board.
At 6 weeks, 15 of 25 subjects preferred cryotherapy (60%), and 9 of 25 preferred curettage (36%). One of 25 was undecided (4%). At greater than 12 months, 11 of 18 preferred cryotherapy (61%), and 7 of 18 preferred curettage (39%). Seven subjects were lost to follow-up.
The patient rating scale for lesion cosmesis ranged from 1 (lesion unchanged) to 10 (normal-appearing skin). Mean ratings for cosmesis (reported as “6-week/>12-month”scores and P values) were 8.58/9.33 for cryotherapy and 8.28/9.39 for curettage (P = .57/ P = .83).
The blinded physician postoperative rating scale for lesion color ranged from −5 (most hypopigmented) to 5 (most hyperpigmented). Blinded physician color ratings were 1.56/1.00 for cryotherapy and 2.6/−0.94 for curettage (P < .001/ P = .004). The blinded physician rating scale for lesion texture ranged from 1 (flat) to 10 (most elevated). Blinded physician postoperative texture ratings were 4.04/3.29 for cryotherapy and 1.76/1.41 curettage (P = .001/ P = .01).
The mean scores for pain with treatment on a 10-point scale (10 most painful) were 2.52 and 1.76 for cryotherapy and curettage treatments, respectively (P = .03). At the longer follow-up time, 7 of 11 patients who preferred cryotherapy over curettage indicated that decreased postoperative wound care was a primary reason for this preference (64%).
This pilot study shows that the majority of patients preferred cryotherapy over curettage at both the 6-week and greater-than-12-month survey time points. This preference is apparently owing to decreased wound care with cryotherapy and is present despite subjects' statistically significant rating of a higher level of pain with cryotherapy compared with curettage. There are no statistically significant differences in subject ratings for cosmesis at either time point.
There are, however, statistically significant differences between the 2 techniques in blinded physician ratings at both time points. More redness at 6 weeks and tendency for hypopigmented scar formation at greater than 12 months occurred with curettage. Leftover SK lesion occurred more frequently with cryotherapy in the short and long term.
Limitations of this study include the following: (1) Enrolled participants had Fitzpatrick skin types 1, 2, or 3; (2) SK lesions may have different properties and treatment responses in different regions of the body (ie, face vs trunk), and therefore, these results may not be generalized to all SK cases; (3) patient preferences may have been influenced by age, with older patients tending to care less about complete resolution of lesions; (4) the study compares only 2 methods of SK removal, and there are other techniques that may be more effective; and (5) generalizability may be limited because in dermatologic practice, there is lack of standardization of cryotherapy technique.
In summary, this study highlights that both cryotherapy and curettage are effective methods of removing SKs that lead to slightly different yet highly satisfactory cosmetic outcomes. The majority of patients preferred cryotherapy for SK removal on the trunk and proximal extremities. If a patient has multiple SKs, it may be appropriate to treat one lesion with each treatment type (or an alternative) and then allow the patient to choose their preference for future treatment of additional lesions.
Correspondence: Dr Wood, Department of Dermatology, Hershey Medical Center Penn State University, 1112 Peggy Dr, Hummelstown, PA 17036 (firstname.lastname@example.org).
Accepted for Publication: July 31, 2012.
Author Contributions: All authors had full access to all of the data in the study and take responsibility for the integrity of the data and the accuracy of the data analysis. Study concept and design: Wood, Hollenbeak, and Miller. Acquisition of data: Wood, Stucki, and Miller. Analysis and interpretation of data: Wood, Hollenbeak, and Miller. Drafting of the manuscript: Wood, Stucki, and Miller. Critical revision of the manuscript for important intellectual content: Wood, Hollenbeak, and Miller. Statistical analysis: Hollenbeak. Administrative, technical, and material support: Wood and Stucki. Study supervision: Wood and Miller.
Conflict of Interest Disclosures: None reported.
Funding/Support: This study was supported in part by the Department of Dermatology at Hershey Medical Center.