Laser and injectable options for treatment of keloids

Various therapies to control excessive scarring, including injection of a gelatin hydrogel scaffold and lasers, were highlighted by two presenters at the lst International Keloid Symposium held recently in New York City.

Although there are standards of care like injectable steroids that most clinicians use to control excessive scarring and keloids, “there is still a need for treatment that is more effective,” says Brian Berman, M.D., Ph.D., an emeritus professor of dermatology and dermatologic surgery at the University of Miami Miller School of Medicine in Miami. Dr. Berman is also co-director of the Center for Clinical and Cosmetic Research in Aventura, Fla

Dr. Berman has been involved with several studies that show that the postsurgical recurrence rate of keloids after roughly one year is 51%, compared to the literature that shows a higher composite recurrence rate of 71%.

“Even worse, is that when the keloid returns, it is often larger than the original keloid, so for that reason it is very important to make some attempts to reduce the rate of post-excision recurrence, if possible,” he says.  

Interferon and imiquimod

Following surgical excision, injecting interferon at the time of surgery and again one week later during suture removal can reduce the recurrence rate from 51% to as low as 19%, Dr. Berman tells Dermatology Times. 

“However, applying simply a cream (imiquimod) to the suture line immediately after keloid incision induces high levels of interferon locally that has been shown to be more efficacious,” he says.

In two smaller, three-month studies, application of imiquimod 5% cream found 0% recurrence and 6% recurrence, respectively, when applied daily for two months post-keloidectomy.

Radiation therapy

Superficial radiation therapy directed to the suture line at a biologically effective dose (BED) also achieved 0% recurrence in patients followed up to one year in one study.

At Dr. Berman’s practice, radiation is given at a dose of 6 Gy, for three consecutive days, with the first fraction scheduled within 24 hours of the excision.

“In general, though, the literature indicates that superficial radiation therapy reduces recurrence to about 20% with up to one year of follow-up, but we may want to extend the follow-up,” Dr. Berman notes. “We have not seen any recurrence, with some patients monitored for a full year.”

Emerging therapies

Emerging therapies to control excessive scarring include a single injection of a gelatin hydrogel scaffold at the completion of surgery, which has reduced the one-year recurrence to the 8% range; and injecting microRNAs that use agents to either mimic or inhibit the microRNAs to regulate a variety of genes pivotal in scarring and fibrosis.

In addition, a low-tech device is available that adheres to the skin on both sides of the keloidectomy suture line.

“Focal adhesion kinase is a cellular protein which actually is activated by mechanical forces, as when the incision site is under tension, and ultimately induces greater collagen production and inflammation, thus causing scars,” Dr. Berman explains. “When you snap the device, the tension is released from the suture line, resulting in less visible scarring.”

NEXT: Treatment options for keloids

Different lasers, different approaches

Dr. BrauerJeremy A. Brauer, M.D., director of clinical research at the Laser & Skin Surgery Center of New York City and a clinical assistant professor of dermatology at New York University, treats patients with various types of scarring on a daily basis.

“These scars can often greatly affect an individual’s quality of life, both physically and psychologically,” Dr. Brauer says.

There are several categories of lasers that are useful in the treatment of scars. Using the theory of selective photothermolysis, and in the case of fractional devices, fractional photothermolysis, “these devices target specific chromophores in the skin; namely, hemoglobin and oxyhemoglobin, melanin and water,” Dr. Brauer explains in a post-symposium interview about his presentation on using lasers to manage scars.

Dr. Brauer says all three of these major chromophores are potential targets in scar treatment, with water being the primary target for ablative and nonablative fractional resurfacing devices. Depending upon the appearance of the scar, these lasers are often used in combination with other lasers, or in combination with intralesional agents such as corticosteroids and antimetabolites, including 5-fluorouracil (5-FU). 

In addition, the pulsed dye laser (PDL) “has been shown to be effective in the treatment of erythematous, as well as hypertrophic scars and keloids,” Dr. Brauer says. “In fact, one of the first published reports of scar improvement with a 585 nm PDL was with concurrent treatment of a port wine stain that also had hypertrophic scarring from previous treatment with an argon laser.” 

Resurfacing lasers that target water is the primary class of lasers used to treat scarring of all types: hypertrophic and atrophic scars, plus those with hyper- or hypopigmentation and erythema.

These resurfacing lasers include traditional ablative devices, such as the 10600 nm CO₂ and 2940 erbium-YAG, and the more recently introduced fractional non ablative and ablative lasers.

“These non ablative fractional counterparts were first developed using infrared wavelengths like the 1550 nm erbium-doped fiber and 1927 nm thulium lasers,” Dr. Brauer says. “While available for a decade now, fractional resurfacing lasers have seen a renewed interest, with impressive reports of success using ablative and non ablative fractional lasers in the treatment of traumatic scarring and wound contractures.” 

Newer devices like picosecond pulse duration lasers have also demonstrated success in the treatment of atrophic acne scarring. And another expanding field is laser-assisted drug delivery, “which uses the channels created by fractional devices to assist in the delivery of topically applied agents, such as corticosteroids,” Dr. Brauer explains. “This novel approach has resulted in the improvement of mobility, texture and appearance of these scars.”

Disclosures:

Dr. Brauer serves on the medical advisory board of Cynosure.

References: None