RALEIGH, N.C. – Punch incision epidermal inclusion cysts located on the trunk leaves a significantly smaller scar than does elliptical excision with a similarly low recurrence rate, according to the results of a randomized trail.
Procedure time was essentially the same for the two techniques, at around 13 minutes. Although punch incision and its wound closure can be easier, it took a fair amount of time to squeeze the cyst contents through the small punch opening and remove the cyst lining using a curette, Dr. Justin T. Cheeley explained at the annual meeting of the Society for Investigative Dermatology.
He reported on 40 consecutive patients with one or more truncal epidermal inclusion cysts 1-3 cm in diameter who were randomized to elliptical excision or punch incision in a head-to-head comparative trial.
The primary study end point – cyst recurrence during 16 months of prospective follow-up – occurred in three patients in the punch incision group and two in the elliptical excision group. Predictors of cyst recurrence were sought, but none could be identified, according to Dr. Cheeley of Emory University, Atlanta.
Most secondary end points were similar for the two study arms, including early and late complication rates, as well as improvement in skin-specific quality of life and patient satisfaction as measured by change in Skindex-16 scores.
Dr. Eric L. Simpson
There was, however, a significant difference between the two study groups in terms of average scar length. In the punch incision group, average scar length was 1.1 cm, compared with 1.8 cm in the elliptical excision group.
The investigators employed a 4-mm punch for the most part, although they turned to a 6-mm punch in treating larger cysts. Punch incision wounds were closed with a single nylon suture. Closure of the elliptical excision sites required more extensive suturing.
Audience member Dr. Eric L. Simpson complimented Dr. Cheeley and his coinvestigators for conducting a study with important cost implications given how often epidermal inclusion cysts are encountered in practice.
“The difference between punch incision and elliptical excision with an intermediate-level repair is probably 10-fold in terms of cost,” said Dr. Simpson of Oregon Health and Science University, Portland.
Dr. Cheeley reported having no financial conflicts.