Quality-switched (QS) laser therapy with a ruby laser and topical triple-combination therapy (TCT) were similarly effective in lightening solar lentigines, based on data from a prospective, open label study of 15 adults. The findings were published in Dermatologic Surgery.

The QS ruby laser (QSRL) delivered longer-lasting skin-lightening results in less time, but the topical therapy is less expensive and has a lower risk of adverse events, wrote Dr. Laurence Imhof of the department of dermatology, University Hospital Zürich, and colleagues (Dermatol Surg. 2016;42:853-57. doi: 10.1097/DSS.0000000000000793 ). “Although therapy [for solar lentigines] is not medically indicated, there is a rising treatment demand for aesthetic reasons. Therefore, the treatment should be very safe and affordable,” they wrote.

The researchers compared the safety and efficacy of treating solar lentigines with a 694-nm QSRL and TCT (hydroquinone 5%, tretinoin 0.03%, and dexamethasone 0.03%). The patients included 14 women and 1 man with evenly distributed solar lentigines on the backs of both hands. Each patient was treated with 1-2 QSRL sessions on the back of the right hand and 7 weeks of once-daily application of TCT on the back of the left hand. The average age of the patients was 61 years; 13 were Fitzpatrick Skin Types II and III. Adverse events were mild and transient with both treatments, although the QSRL caused significantly more crusting and hyperpigmentation than the TCT.

Both treatments significantly reduced pigment at the end of treatment (day 56) and 12 weeks’ post treatment (140 days), compared with baseline. Treatment areas were evaluated at days 28, 56, and 140 by the treating physician, the patient, and a blinded physician (based on photos).The 6-point grading scale rated the degree of lightening/percentage of clearing, ranging from worse (less than 0%) to excellent (76%-100%).

At 56 days, the mean macroscopic improvement with QSRL laser was rated 3.5 by the treating physician and patient and 3 by a blinded physician; the mean macroscopic improvement with TCT was rated 2.4 by the treating physician, 2.2 by the patient, and 1.7 by the blinded physician. At 140 days, the mean macroscopic improvements with the laser were rated 2.9 by the treating physician, 2.7 by the patient, and 2.8 by the blinded physician, compared with 1.2, 1.1, and 0.7, respectively, with TCT.

The results were limited by the small size, short follow-up period, and open-label design, the researchers noted. However, the study is the first known to compare a laser and a topical treatment for the management of solar lentigines, and the findings suggest that both therapies can be recommended for the aesthetic treatment of solar lentigines, they said.

The TCT cream used in the study was provided by Louis Widmer SA, which provided a grant to the University of Zürich. The researchers had no financial conflicts to disclose.