keloid resume
TRANSCRIPT
-
8/13/2019 Keloid Resume
1/23
KELOID
Keloids and hypertrophic scars represent an exuberant healing response that poses a
challenge for physicians. Patients at high risk of keloids are usually younger than 30
years and have darker skin. Sternal skin, shoulders and upper arms, earlobes, andcheeks are most susceptible to developing keloids and hypertrophic scars. High-risk
trauma includes burns, ear piercing, and any factor that prolongs wound healing. Keloid
formation often can be prevented if anticipated with immediate silicone elastomer
sheeting, taping to reduce skin tension, or corticosteroid injections. Once established,
however, keloids are difficult to treat, with a high recurrence rate regardless of therapy.
Evidence supports silicone sheeting, pressure dressings, and corticosteroid injections
as first-line treatments. Cryotherapy may be useful, but should be reserved for smaller
lesions. Surgical removal of keloids poses a high recurrence risk unless combined with
one or several of these standard therapies. Alternative postsurgical options for refractoryscars include pulsed dye laser, radiation, and possibly imiquimod cream. Intralesional
verapamil, fluorouracil, bleomycin, and interferon alfa-2b injections appear to be
beneficial for treatment of established keloids. Despite the popularity of over-the-counter
herb-based creams, the evidence for their use is mixed, and there is little evidence that
vitamin E is helpful.
Keloids are elevated fibrous scars that extend beyond the borders of the original wound, do not
regress, and usually recur after excision. The term is coined from the Greek word cheloides,
meaning crab's claw.1 Hypertrophic scars are similar, but are confined to the wound borders
and usually regress over time (Table 1).1,2Scar hypertrophy usually appears within a month of
injury, whereas keloids may take three months or even years to develop.3Both represent
abnormal responses to dermal injury, with exuberant deposition of collagen developing over
three basic stages: (1) inflammation (first three to 10 days); (2) proliferation (next 10 to 14 days);
and (3) maturation or remodeling (two weeks to years).1The treatments for keloids and
hypertrophic scars are similar, but hypertrophic scars have a better prognosis.
Risk Factors and Etiology
The primary risk factor for keloids is darkly pigmented skin, which carries a 15- to 20-foldincreased risk, perhaps because of melanocyte-stimulating hormone anomalies.4Familial
predisposition, with autosomal dominant and recessive genetic variants is recognized.5Black,
Hispanic, and Asian persons are far more likely to develop keloids than white
persons.6,7Hypertrophic scars, however, are less likely to be associated with skin pigmentation.
http://www.aafp.org/afp/2009/0801/p253.html#afp20090801p253-b1http://www.aafp.org/afp/2009/0801/p253.html#afp20090801p253-b1http://www.aafp.org/afp/2009/0801/p253.html#afp20090801p253-b1http://www.aafp.org/afp/2009/0801/p253.html#afp20090801p253-t1http://www.aafp.org/afp/2009/0801/p253.html#afp20090801p253-t1http://www.aafp.org/afp/2009/0801/p253.html#afp20090801p253-t1http://www.aafp.org/afp/2009/0801/p253.html#afp20090801p253-b1http://www.aafp.org/afp/2009/0801/p253.html#afp20090801p253-b1http://www.aafp.org/afp/2009/0801/p253.html#afp20090801p253-b2http://www.aafp.org/afp/2009/0801/p253.html#afp20090801p253-b2http://www.aafp.org/afp/2009/0801/p253.html#afp20090801p253-b2http://www.aafp.org/afp/2009/0801/p253.html#afp20090801p253-b3http://www.aafp.org/afp/2009/0801/p253.html#afp20090801p253-b3http://www.aafp.org/afp/2009/0801/p253.html#afp20090801p253-b3http://www.aafp.org/afp/2009/0801/p253.html#afp20090801p253-b1http://www.aafp.org/afp/2009/0801/p253.html#afp20090801p253-b1http://www.aafp.org/afp/2009/0801/p253.html#afp20090801p253-b1http://www.aafp.org/afp/2009/0801/p253.html#afp20090801p253-b4http://www.aafp.org/afp/2009/0801/p253.html#afp20090801p253-b4http://www.aafp.org/afp/2009/0801/p253.html#afp20090801p253-b4http://www.aafp.org/afp/2009/0801/p253.html#afp20090801p253-b5http://www.aafp.org/afp/2009/0801/p253.html#afp20090801p253-b5http://www.aafp.org/afp/2009/0801/p253.html#afp20090801p253-b5http://www.aafp.org/afp/2009/0801/p253.html#afp20090801p253-b6http://www.aafp.org/afp/2009/0801/p253.html#afp20090801p253-b6http://www.aafp.org/afp/2009/0801/p253.html#afp20090801p253-b7http://www.aafp.org/afp/2009/0801/p253.html#afp20090801p253-b7http://www.aafp.org/afp/2009/0801/p253.html#afp20090801p253-b7http://www.aafp.org/afp/2009/0801/p253.html#afp20090801p253-b7http://www.aafp.org/afp/2009/0801/p253.html#afp20090801p253-b6http://www.aafp.org/afp/2009/0801/p253.html#afp20090801p253-b5http://www.aafp.org/afp/2009/0801/p253.html#afp20090801p253-b4http://www.aafp.org/afp/2009/0801/p253.html#afp20090801p253-b1http://www.aafp.org/afp/2009/0801/p253.html#afp20090801p253-b3http://www.aafp.org/afp/2009/0801/p253.html#afp20090801p253-b2http://www.aafp.org/afp/2009/0801/p253.html#afp20090801p253-b1http://www.aafp.org/afp/2009/0801/p253.html#afp20090801p253-t1http://www.aafp.org/afp/2009/0801/p253.html#afp20090801p253-b1 -
8/13/2019 Keloid Resume
2/23
Keloids are more common in persons younger than 30 years, with risk peaking between 10 to
20 years of age, and in patients with elevated hormone levels (e.g., during puberty or
pregnancy).8Sternal skin, shoulders and upper arms, earlobes, and cheeks are most susceptible
to developing keloids9(Figure 1). Certain types of trauma and delayed healing (longer than
three weeks) heighten keloid incidence even more, with burns carrying the highest risk. Acne,ear piercing, chickenpox, vaccinations (particularly bacille Calmette-Gurin vaccination), biopsy
procedures, and lacerations may cause abnormal scarring (Figure 2). Acne keloids are
particularly common. Keloids are more than just cosmetically unacceptable; many are also
pruritic and painful. They often result in severe emotional distress.
Figure 1.
Cheeks are a common location for keloids, often secondary to acne.
Copyright Logical Images, Inc.
Figure 2.
http://www.aafp.org/afp/2009/0801/p253.html#afp20090801p253-b8http://www.aafp.org/afp/2009/0801/p253.html#afp20090801p253-b8http://www.aafp.org/afp/2009/0801/p253.html#afp20090801p253-b9http://www.aafp.org/afp/2009/0801/p253.html#afp20090801p253-b9http://www.aafp.org/afp/2009/0801/p253.html#afp20090801p253-b9http://www.aafp.org/afp/2009/0801/p253.html#afp20090801p253-f1http://www.aafp.org/afp/2009/0801/p253.html#afp20090801p253-f1http://www.aafp.org/afp/2009/0801/p253.html#afp20090801p253-f1http://www.aafp.org/afp/2009/0801/p253.html#afp20090801p253-f2http://www.aafp.org/afp/2009/0801/p253.html#afp20090801p253-f2http://www.aafp.org/afp/2009/0801/p253.html#afp20090801p253-f2http://www.aafp.org/afp/2009/0801/p253.html#afp20090801p253-f2http://www.aafp.org/afp/2009/0801/p253.html#afp20090801p253-f1http://www.aafp.org/afp/2009/0801/p253.html#afp20090801p253-b9http://www.aafp.org/afp/2009/0801/p253.html#afp20090801p253-b8 -
8/13/2019 Keloid Resume
3/23
Mild trauma, often from shaving, can result in formation of a keloid, such as this onealong the hairline.
Prevention
Before any surgical procedure, patients should be asked if they have had previous problems
with scarring. Discuss the potential for keloids as part of informed consent, and discourage ear
piercing and other elective procedures in persons with dark skin. If ears are pierced despite this
advice, pressure earrings are commercially available for reducing keloid risk. If surgery cannot
be avoided in a high-risk patient, immediate silicone elastomer sheeting or corticosteroid
injections should be instituted. Anything that expedites wound healing and diminishes skin
tension (e.g., postsurgical taping for 12 weeks) will diminish risk.10The cosmetic outcome of
wounds closed with standard suture techniques appears to be similar to that of those closed
with 2-octyl cyanoacrylate dermal adhesive (Dermabond). One small study showed that
hypertrophic scars occurred in five out of 24 repairs with Dermabond versus three out of 28
repairs with traditional suture.11
Treatment
Keloid and hypertrophic scar therapy is challenging and controversial (Table 2).1,79,1221Both
conditions respond to the same therapies, but hypertrophic scars are easier to treat. The large
number of treatment options is a reflection of the poor quality of research on this topic, with no
single proven best treatment or combination of treatments. First-line options include silicone
sheeting, pressure treatment, and corticosteroid injections, but all of these require exemplary
adherence and follow-up. Cryotherapy is useful, but only for smaller lesions, such as those
resulting from acne. Cryotherapy may cause hypopigmentation in patients with dark skin.
Surgical removal of keloids, although temporarily gratifying, is almost invariably followed (50 to
100 percent) by even more aggressive regrowth of scar tissue.8Therefore, all surgical options
http://www.aafp.org/afp/2009/0801/p253.html#afp20090801p253-b10http://www.aafp.org/afp/2009/0801/p253.html#afp20090801p253-b10http://www.aafp.org/afp/2009/0801/p253.html#afp20090801p253-b10http://www.aafp.org/afp/2009/0801/p253.html#afp20090801p253-b11http://www.aafp.org/afp/2009/0801/p253.html#afp20090801p253-b11http://www.aafp.org/afp/2009/0801/p253.html#afp20090801p253-b11http://www.aafp.org/afp/2009/0801/p253.html#afp20090801p253-t2http://www.aafp.org/afp/2009/0801/p253.html#afp20090801p253-t2http://www.aafp.org/afp/2009/0801/p253.html#afp20090801p253-t2http://www.aafp.org/afp/2009/0801/p253.html#afp20090801p253-b1http://www.aafp.org/afp/2009/0801/p253.html#afp20090801p253-b1http://www.aafp.org/afp/2009/0801/p253.html#afp20090801p253-b7http://www.aafp.org/afp/2009/0801/p253.html#afp20090801p253-b7http://www.aafp.org/afp/2009/0801/p253.html#afp20090801p253-b9http://www.aafp.org/afp/2009/0801/p253.html#afp20090801p253-b9http://www.aafp.org/afp/2009/0801/p253.html#afp20090801p253-b12http://www.aafp.org/afp/2009/0801/p253.html#afp20090801p253-b12http://www.aafp.org/afp/2009/0801/p253.html#afp20090801p253-b21http://www.aafp.org/afp/2009/0801/p253.html#afp20090801p253-b21http://www.aafp.org/afp/2009/0801/p253.html#afp20090801p253-b21http://www.aafp.org/afp/2009/0801/p253.html#afp20090801p253-b8http://www.aafp.org/afp/2009/0801/p253.html#afp20090801p253-b8http://www.aafp.org/afp/2009/0801/p253.html#afp20090801p253-b8http://www.aafp.org/afp/2009/0801/p253.html#afp20090801p253-b8http://www.aafp.org/afp/2009/0801/p253.html#afp20090801p253-b21http://www.aafp.org/afp/2009/0801/p253.html#afp20090801p253-b12http://www.aafp.org/afp/2009/0801/p253.html#afp20090801p253-b9http://www.aafp.org/afp/2009/0801/p253.html#afp20090801p253-b7http://www.aafp.org/afp/2009/0801/p253.html#afp20090801p253-b1http://www.aafp.org/afp/2009/0801/p253.html#afp20090801p253-t2http://www.aafp.org/afp/2009/0801/p253.html#afp20090801p253-b11http://www.aafp.org/afp/2009/0801/p253.html#afp20090801p253-b10 -
8/13/2019 Keloid Resume
4/23
should be followed by corticosteroid injections, silicone sheeting, or these options combined
with pulsed dye laser. A variety of other choices are emerging, but are less well studied.
CORTICOSTEROID INJECTIONS
Corticosteroid injections for prevention and treatment of keloids and hypertrophic scars areperhaps the first-line option for family physicians. Corticosteroids suppress inflammation and
mitosis while increasing vasoconstriction in the scar. Triamcinolone acetonide suspension
(Kenalog) 10 to 40 mg per mL (depending on the site) is injected intralesionally, which, although
painful, will eventually flatten 50 to 100 percent of keloids, with a 9 to 50 percent recurrence
rate.9Lidocaine (Xylocaine) may be combined with the corticosteroid to lessen pain, whereas
using adjunctive cryotherapy immediately before injection may make the procedure easier by
softening the scar (based on expert opinion).22Combining cryotherapy and corticosteroid
injections also improves outcomes more than either modality alone, although hypopigmentation
is always a significant concern.23,24
Usually, two or three injections are given a month apart;however, therapy can continue for six months or longer.25Newer keloids are more responsive to
therapy than older, established lesions. Corticosteroid injections are more effective if combined
with surgery; the sooner instituted, the greater the likelihood of success. Common adverse
effects include atrophy, telangiectasias, and hypopigmentation.
SILICONE SHEETING
Silicone elastomer sheeting is a noninvasive and extensively studied approach to the prevention
and treatment of keloids and hypertrophic scars. Silicone sheets are thought to work by
increasing the temperature, hydration, and perhaps the oxygen tension of the occluded scar,causing it to soften and flatten.8This technique should be avoided on open wounds, but can be
applied as soon as the skin heals. More than 60 products have been marketed, including
silicone sheets, strips, gels, sprays, and foams. Most are available over the counter, but can be
expensive. To be effective, sheets must be worn over the scar for 12 to 24 hours per day for two
to three months.8The sheet and the scar should be washed daily with mild soap and water. The
sheets can be reused until they start to disintegrate. Although most studies suggest silicone
sheeting results in fewer scars in persons at risk, a recent Cochrane review concluded that most
research in this area was of poor quality and highly susceptible to bias.26Similar to silicone
sheeting is the use of pressure dressings or garments, especially for the prevention of burnscars. However, pressure dressings (24 to 30 mm Hg) must be worn for six to 12 months, which
is difficult and uncomfortable for most patients.27
http://www.aafp.org/afp/2009/0801/p253.html#afp20090801p253-b9http://www.aafp.org/afp/2009/0801/p253.html#afp20090801p253-b9http://www.aafp.org/afp/2009/0801/p253.html#afp20090801p253-b9http://www.aafp.org/afp/2009/0801/p253.html#afp20090801p253-b22http://www.aafp.org/afp/2009/0801/p253.html#afp20090801p253-b22http://www.aafp.org/afp/2009/0801/p253.html#afp20090801p253-b23http://www.aafp.org/afp/2009/0801/p253.html#afp20090801p253-b23http://www.aafp.org/afp/2009/0801/p253.html#afp20090801p253-b24http://www.aafp.org/afp/2009/0801/p253.html#afp20090801p253-b24http://www.aafp.org/afp/2009/0801/p253.html#afp20090801p253-b24http://www.aafp.org/afp/2009/0801/p253.html#afp20090801p253-b25http://www.aafp.org/afp/2009/0801/p253.html#afp20090801p253-b25http://www.aafp.org/afp/2009/0801/p253.html#afp20090801p253-b25http://www.aafp.org/afp/2009/0801/p253.html#afp20090801p253-b8http://www.aafp.org/afp/2009/0801/p253.html#afp20090801p253-b8http://www.aafp.org/afp/2009/0801/p253.html#afp20090801p253-b8http://www.aafp.org/afp/2009/0801/p253.html#afp20090801p253-b8http://www.aafp.org/afp/2009/0801/p253.html#afp20090801p253-b8http://www.aafp.org/afp/2009/0801/p253.html#afp20090801p253-b8http://www.aafp.org/afp/2009/0801/p253.html#afp20090801p253-b26http://www.aafp.org/afp/2009/0801/p253.html#afp20090801p253-b26http://www.aafp.org/afp/2009/0801/p253.html#afp20090801p253-b26http://www.aafp.org/afp/2009/0801/p253.html#afp20090801p253-b27http://www.aafp.org/afp/2009/0801/p253.html#afp20090801p253-b27http://www.aafp.org/afp/2009/0801/p253.html#afp20090801p253-b27http://www.aafp.org/afp/2009/0801/p253.html#afp20090801p253-b27http://www.aafp.org/afp/2009/0801/p253.html#afp20090801p253-b26http://www.aafp.org/afp/2009/0801/p253.html#afp20090801p253-b8http://www.aafp.org/afp/2009/0801/p253.html#afp20090801p253-b8http://www.aafp.org/afp/2009/0801/p253.html#afp20090801p253-b25http://www.aafp.org/afp/2009/0801/p253.html#afp20090801p253-b24http://www.aafp.org/afp/2009/0801/p253.html#afp20090801p253-b23http://www.aafp.org/afp/2009/0801/p253.html#afp20090801p253-b22http://www.aafp.org/afp/2009/0801/p253.html#afp20090801p253-b9 -
8/13/2019 Keloid Resume
5/23
COMBINATION THERAPY FOLLOWING SURGERY
If neither silicone nor corticosteroids are effective over 12 months, second-line surgical
treatment followed by corticosteroids and possibly silicone sheeting should be considered. The
use of corticosteroid injections following keloid surgery reduces the recurrence rate to lless than
50 percent.28Scar excision may be complete, or a minute remnant of scar may be left on the
wound margin, which may reduce recurrence (based on expert opinion). Immediate wound edge
corticosteroid injection after the excision is followed by weekly injections for two to five weeks
and monthly injections for three to six months.9A triple keloid therapy combining surgery,
corticosteroids, and silicone sheeting has been shown to be even more effective, with only a
12.5 percent recurrence rate after 13 months.14However, this approach was described as
tedious and time intensive by the author of the study and requires a motivated patient.
IMIQUIMOD
Imiquimod 5% cream (Aldara), an immune response modifier that enhances healing, has also
been used to help prevent keloid recurrence after surgical excision. The cream is applied on
alternate nights for eight weeks after surgery. Although the trials have been small, the
postsurgical recurrence rate averaged only 28 percent over a six- to nine-month follow-up
period, with best results (2.9 percent recurrence) in low skin tension areas such as
earlobes.12Adverse effects include irritation and hyperpigmentation.
PULSED DYE LASER
Treatment of keloids with short-pulsed, 585-nm pulsed dye laser has shown limited promise,
with a 57 to 83 percent improvement rate.15It is more vascular-specific than other lasertherapies and appears to be most effective if used early and in conjunction with other
techniques. Laser-treated portions of keloidal median sternotomy scars showed significant
improvement in erythema, pruritus, and scar height compared with untreated portions of the
same scars, and these improvements persisted for at least six months.16The principal effect of
a pulsed dye laser is on scar microvasculature, reducing erythema and pruritus and improving
skin texture. The effectiveness of this therapy remains controversial, however, with other studies
showing insignificant reduction in scar thickness.29Disadvantages include significant expense
and availability only through a specialist.
OTHER THERAPIES
Other therapies with limited studies include intralesional verapamil, fluorouracil, bleomycin, and
interferon alfa-2b injections. Although all of these have results comparable or sometimes
superior to corticosteroid injection and silicone sheeting, the optimal keloid therapy remains
undefined. Combinations of therapies have proved superior to individual approaches.
http://www.aafp.org/afp/2009/0801/p253.html#afp20090801p253-b28http://www.aafp.org/afp/2009/0801/p253.html#afp20090801p253-b28http://www.aafp.org/afp/2009/0801/p253.html#afp20090801p253-b28http://www.aafp.org/afp/2009/0801/p253.html#afp20090801p253-b9http://www.aafp.org/afp/2009/0801/p253.html#afp20090801p253-b9http://www.aafp.org/afp/2009/0801/p253.html#afp20090801p253-b9http://www.aafp.org/afp/2009/0801/p253.html#afp20090801p253-b14http://www.aafp.org/afp/2009/0801/p253.html#afp20090801p253-b14http://www.aafp.org/afp/2009/0801/p253.html#afp20090801p253-b14http://www.aafp.org/afp/2009/0801/p253.html#afp20090801p253-b12http://www.aafp.org/afp/2009/0801/p253.html#afp20090801p253-b12http://www.aafp.org/afp/2009/0801/p253.html#afp20090801p253-b12http://www.aafp.org/afp/2009/0801/p253.html#afp20090801p253-b15http://www.aafp.org/afp/2009/0801/p253.html#afp20090801p253-b15http://www.aafp.org/afp/2009/0801/p253.html#afp20090801p253-b15http://www.aafp.org/afp/2009/0801/p253.html#afp20090801p253-b16http://www.aafp.org/afp/2009/0801/p253.html#afp20090801p253-b16http://www.aafp.org/afp/2009/0801/p253.html#afp20090801p253-b16http://www.aafp.org/afp/2009/0801/p253.html#afp20090801p253-b29http://www.aafp.org/afp/2009/0801/p253.html#afp20090801p253-b29http://www.aafp.org/afp/2009/0801/p253.html#afp20090801p253-b29http://www.aafp.org/afp/2009/0801/p253.html#afp20090801p253-b16http://www.aafp.org/afp/2009/0801/p253.html#afp20090801p253-b15http://www.aafp.org/afp/2009/0801/p253.html#afp20090801p253-b12http://www.aafp.org/afp/2009/0801/p253.html#afp20090801p253-b14http://www.aafp.org/afp/2009/0801/p253.html#afp20090801p253-b9http://www.aafp.org/afp/2009/0801/p253.html#afp20090801p253-b28 -
8/13/2019 Keloid Resume
6/23
Intralesional verapamil (2.5 mg per mL) in conjunction with silicone sheeting reduced keloid
postsurgical recurrence by 90 percent at 18 months (54 percent of patients were keloid-free; 36
percent had partial success) compared with only 18 percent showing any improvement with
silicone sheeting alone (no patients were keloid-free).17Calcium antagonists appear to work by
reducing collagen production and may be a reasonable and safe alternative to corticosteroidinjection in the future.
Intralesional fluorouracil (50 mg per mL, two to three times per week) appears to shrink keloids
safely while avoiding the tissue atrophy and telangiectasia that may occur with repeated
corticosteroid injections.30Combining fluorouracil with corticosteroid injections and pulsed dye
laser produced superior results more rapidly than corticosteroid injections alone or
corticosteroids with fluorouracil.13Good to excellent responses at 12 weeks as rated by a
blinded observer were 15 percent for triamcinolone acetonide, 40 percent for triamcinolone plus
fluorouracil, and 70 percent for all three modalities (all significant). Combining corticosteroids
and fluorouracil diminished the adverse effects of corticosteroids. Rare skin complications of
fluorouracil may include hyperpigmentation and wound ulceration. No systemic adverse effects
(e.g., anemia, leucopenia, thrombocytopenia) occurred in this study.
Bleomycin is another useful chemotherapeutic agent; a standard approach is bleomycin
tattooing 0.1 mL (1.5 IU per mL) over two to six sessions, with a maximal dose of 6
mL.31Results of one study showed a total regression of 84 percent.18Multiple intralesional
punctures are probably safe because it is likely that less than 5 percent of the dose ever
reaches the bloodstream.18Compared with triamcinolone injections combined with cryotherapy,
bleomycin tattoo performed significantly better for keloids larger than 100 mm2(P=
.03).19Systemically administered bleomycin is capable of causing pulmonary fibrosis (at doses
greater than 400 U) and various cutaneous reactions (at doses of 200 to 300 U), including hair
loss, hyperpigmentation, fibrosis, and vasospasm, any of which warrants cessation of
treatment.32
Intralesional interferon alfa-2b (1.5 million IU twice daily for four days) reduced keloid size by 50
percent over nine days, proving superior to intralesional corticosteroids.31Interferon alfa-2b was
also more effective than corticosteroids for preventing keloid recurrence after excision. Injection
pain and expense (about $100 per treatment) are the main concerns. A liposome-encapsulatedinterferon alfa-2b cream is also being investigated for scar reduction.33
Radiation, alone or (more commonly) after keloid excision, is a much more controversial option.
It may pose a risk of local growth inhibition in children and possibly subsequent cancer.
Commondosesrangebetween1,500to 2,000 rads over five to six sessions following
surgery.28The success rate for radiation alone is 56 percent (range of 10 to 94 percent), but this
http://www.aafp.org/afp/2009/0801/p253.html#afp20090801p253-b17http://www.aafp.org/afp/2009/0801/p253.html#afp20090801p253-b17http://www.aafp.org/afp/2009/0801/p253.html#afp20090801p253-b17http://www.aafp.org/afp/2009/0801/p253.html#afp20090801p253-b30http://www.aafp.org/afp/2009/0801/p253.html#afp20090801p253-b30http://www.aafp.org/afp/2009/0801/p253.html#afp20090801p253-b30http://www.aafp.org/afp/2009/0801/p253.html#afp20090801p253-b13http://www.aafp.org/afp/2009/0801/p253.html#afp20090801p253-b13http://www.aafp.org/afp/2009/0801/p253.html#afp20090801p253-b13http://www.aafp.org/afp/2009/0801/p253.html#afp20090801p253-b31http://www.aafp.org/afp/2009/0801/p253.html#afp20090801p253-b31http://www.aafp.org/afp/2009/0801/p253.html#afp20090801p253-b31http://www.aafp.org/afp/2009/0801/p253.html#afp20090801p253-b18http://www.aafp.org/afp/2009/0801/p253.html#afp20090801p253-b18http://www.aafp.org/afp/2009/0801/p253.html#afp20090801p253-b18http://www.aafp.org/afp/2009/0801/p253.html#afp20090801p253-b18http://www.aafp.org/afp/2009/0801/p253.html#afp20090801p253-b18http://www.aafp.org/afp/2009/0801/p253.html#afp20090801p253-b18http://www.aafp.org/afp/2009/0801/p253.html#afp20090801p253-b19http://www.aafp.org/afp/2009/0801/p253.html#afp20090801p253-b19http://www.aafp.org/afp/2009/0801/p253.html#afp20090801p253-b19http://www.aafp.org/afp/2009/0801/p253.html#afp20090801p253-b32http://www.aafp.org/afp/2009/0801/p253.html#afp20090801p253-b32http://www.aafp.org/afp/2009/0801/p253.html#afp20090801p253-b32http://www.aafp.org/afp/2009/0801/p253.html#afp20090801p253-b31http://www.aafp.org/afp/2009/0801/p253.html#afp20090801p253-b31http://www.aafp.org/afp/2009/0801/p253.html#afp20090801p253-b31http://www.aafp.org/afp/2009/0801/p253.html#afp20090801p253-b33http://www.aafp.org/afp/2009/0801/p253.html#afp20090801p253-b33http://www.aafp.org/afp/2009/0801/p253.html#afp20090801p253-b33http://www.aafp.org/afp/2009/0801/p253.html#afp20090801p253-b28http://www.aafp.org/afp/2009/0801/p253.html#afp20090801p253-b28http://www.aafp.org/afp/2009/0801/p253.html#afp20090801p253-b28http://www.aafp.org/afp/2009/0801/p253.html#afp20090801p253-b28http://www.aafp.org/afp/2009/0801/p253.html#afp20090801p253-b33http://www.aafp.org/afp/2009/0801/p253.html#afp20090801p253-b31http://www.aafp.org/afp/2009/0801/p253.html#afp20090801p253-b32http://www.aafp.org/afp/2009/0801/p253.html#afp20090801p253-b19http://www.aafp.org/afp/2009/0801/p253.html#afp20090801p253-b18http://www.aafp.org/afp/2009/0801/p253.html#afp20090801p253-b18http://www.aafp.org/afp/2009/0801/p253.html#afp20090801p253-b31http://www.aafp.org/afp/2009/0801/p253.html#afp20090801p253-b13http://www.aafp.org/afp/2009/0801/p253.html#afp20090801p253-b30http://www.aafp.org/afp/2009/0801/p253.html#afp20090801p253-b17 -
8/13/2019 Keloid Resume
7/23
increases to 76 percent (range of 25 to 100 percent) if administered immediately after
surgery.9Another study showed a 67 percent success rate with radiation, increasing to 75
percent if delivered within 48 hours of surgery.20Most physicians would reserve radiation as a
last resort for keloids refractory to all other approaches.
OVER-THE-COUNTER TREATMENTS
Many patients use topical vitamin E (alpha-tocopherol) hoping its antioxidant properties will
prevent scars. However, there is little evidence that it is helpful, and some patients develop a
contact dermatitis that may delay healing.34Used early on, vitamin E may also reduce the
tensile strength of the scar, and its use should be discouraged.
Another over-the-counter option is onion extract topical gels (e.g., Mederma), but limited clinical
trials have failed to demonstrate any clinical improvement in scar height, erythema, or
pruritis.35,36Contractubex gel (not available in the United States) contains onion extract with
heparin, which is thought to promote scar maturity. Although one trial compared this product
favorably with corticosteroids, another showed that it was ineffective in improving scar height
and itching.21,37
Moist exposed burn ointment contains multiple herbs with betasitosterol, which provides
hydration and possible benefits to wound healing.38Another plant extract product
contains Centella asiaticaand Bulbine frutescens(Alpha Centella cream), which may increase
wound strength if used in the first six to eight weeks.39All of these commercially available
products emphasize preventive use because they are unlikely to reverse well-established
keloids.
http://www.aafp.org/afp/2009/0801/p253.html#afp20090801p253-b9http://www.aafp.org/afp/2009/0801/p253.html#afp20090801p253-b9http://www.aafp.org/afp/2009/0801/p253.html#afp20090801p253-b9http://www.aafp.org/afp/2009/0801/p253.html#afp20090801p253-b20http://www.aafp.org/afp/2009/0801/p253.html#afp20090801p253-b20http://www.aafp.org/afp/2009/0801/p253.html#afp20090801p253-b20http://www.aafp.org/afp/2009/0801/p253.html#afp20090801p253-b34http://www.aafp.org/afp/2009/0801/p253.html#afp20090801p253-b34http://www.aafp.org/afp/2009/0801/p253.html#afp20090801p253-b34http://www.aafp.org/afp/2009/0801/p253.html#afp20090801p253-b35http://www.aafp.org/afp/2009/0801/p253.html#afp20090801p253-b35http://www.aafp.org/afp/2009/0801/p253.html#afp20090801p253-b36http://www.aafp.org/afp/2009/0801/p253.html#afp20090801p253-b36http://www.aafp.org/afp/2009/0801/p253.html#afp20090801p253-b21http://www.aafp.org/afp/2009/0801/p253.html#afp20090801p253-b21http://www.aafp.org/afp/2009/0801/p253.html#afp20090801p253-b37http://www.aafp.org/afp/2009/0801/p253.html#afp20090801p253-b37http://www.aafp.org/afp/2009/0801/p253.html#afp20090801p253-b37http://www.aafp.org/afp/2009/0801/p253.html#afp20090801p253-b38http://www.aafp.org/afp/2009/0801/p253.html#afp20090801p253-b38http://www.aafp.org/afp/2009/0801/p253.html#afp20090801p253-b38http://www.aafp.org/afp/2009/0801/p253.html#afp20090801p253-b39http://www.aafp.org/afp/2009/0801/p253.html#afp20090801p253-b39http://www.aafp.org/afp/2009/0801/p253.html#afp20090801p253-b39http://www.aafp.org/afp/2009/0801/p253.html#afp20090801p253-b39http://www.aafp.org/afp/2009/0801/p253.html#afp20090801p253-b38http://www.aafp.org/afp/2009/0801/p253.html#afp20090801p253-b37http://www.aafp.org/afp/2009/0801/p253.html#afp20090801p253-b21http://www.aafp.org/afp/2009/0801/p253.html#afp20090801p253-b36http://www.aafp.org/afp/2009/0801/p253.html#afp20090801p253-b35http://www.aafp.org/afp/2009/0801/p253.html#afp20090801p253-b34http://www.aafp.org/afp/2009/0801/p253.html#afp20090801p253-b20http://www.aafp.org/afp/2009/0801/p253.html#afp20090801p253-b9 -
8/13/2019 Keloid Resume
8/23
Medical Care
No single therapeutic modality is best for all keloids. The location, size, and depth of the lesion;the age of the patient; and the past response to treatment determine the type of therapy used.
Prevention is key, but therapeutic treatment of hypertrophic scars and keloids includes occlusivedressings, compression therapy, intralesional corticosteroid injections, cryosurgery, excision,radiation therapy, laser therapy, interferon (IFN) therapy, 5-fluorouracil (5-FU), doxorubicin,bleomycin, verapamil, retinoic acid, imiquimod 5% cream, tamoxifen, tacrolimus, botulinumtoxin, and over-the-counter treatments (eg, onion extract; combination of hydrocortisone, silicon,and vitamin E).
Other promising therapies include antiangiogenic factors, including vascular endothelial growthfactor (VEGF) inhibitors (eg, bevacizumab), phototherapy (photodynamic therapy [PDT], UVA-1therapy, narrowband UVB therapy), transforming growth factor (TGF)beta3, tumor necrosisfactor (TNF)-alpha inhibitors (etanercept), and recombinant human interleukin (rhIL-10), whichare directed at decreasing collagen synthesis.
Prevention
Prevention is the first rule in keloid therapy. Avoid performing nonessential cosmetic surgery inpatients known to form keloids; however, the risk is lower among patients who have onlyearlobe lesions. Close all surgical wounds with minimal tension. Incisions should not cross jointspaces. Avoid making midchest incisions, and ensure that incisions follow skin creaseswhenever possible.
Standard Treatments
These include occlusive dressings, compression therapy, and intralesional corticosteroidinjections.
Occlusive dressings
Occlusive dressings include silicone gel sheets and dressings, nonsilicone occlusive sheets,and Cordran tape. These measures have been used with varied success. Antikeloidal effectsappear to result from a combination of occlusion and hydration, rather than from an effect of thesilicone.
Previous studies have shown that in patients treated with silicone occlusive sheeting withpressure worn 24 h/d for up to 12 months, 34% showed excellent improvement, 37.5% showedmoderate improvement, and 28% demonstrated no or slight improvement.
Of patients treated with semipermeable, semiocclusive, nonsilicone-based dressings for 8weeks, 60% experienced flattening of keloids, 71% had reduced pain, 78% had reducedtenderness, 80% had reduced pruritus, 87.5% had reduced erythema, and 90% were satisfiedwith the treatment.
Cordran tape is a clear surgical tape that contains flurandrenolide, a steroid that is uniformlydistributed on each square centimeter of the tape, and it has been shown to soften and flattenkeloids over time.
-
8/13/2019 Keloid Resume
9/23
Compression therapy
Compression therapy involves pressure, which has long been known to have thinning effects onskin. Reduction in the cohesiveness of collagen fibers in pressure-treated hypertrophic scarshas been demonstrated by electron microscopy.
Compression treatments include button compression, pressure earrings, ACE bandages, elasticadhesive bandages, compression wraps, spandex or elastane (Lycra) bandages, and supportbandages. In one study, button compression (2 buttons sandwiching the earlobe applied afterkeloid excision) prevented recurrence during 8 months to 4 years of follow-up observation.
Other pressure devices include pressure earrings and pressure-gradient garments made oflightweight porous Dacron, spandex (also known as elastane), bobbinet fabric (usually worn 12-24 h/d), and zinc oxide adhesive plaster. Overall, 60% of patients treated with these devicesshowed 75-100% improvement.
Corticosteroids
Corticosteroids, specifically intralesional corticosteroid injections, have been the mainstay of
treatment. Corticosteroids reduce excessive scarring by reducing collagen synthesis, alteringglucosaminoglycan synthesis, and reducing production of inflammatory mediators and fibroblastproliferation during wound healing. The most commonly used corticosteroid is triamcinoloneacetonide (TAC) in concentrations of 10-40 mg/mL administered intralesionally with a 25- to 27-gauge needle at 4- to 6-week intervals.
Intralesional steroid therapy as a single modality and as an adjunct to excision has been shownto be efficacious in various studies. Response rates varied from 50-100%, with recurrence ratesof 9-50% in completely resolved scars. When combined with excision, postoperativeintralesional TAC injections yielded a recurrence rate of 0-100%, with most studies citing a rateof less than 50%. Complications of repeated corticosteroid injections include atrophy,telangiectasia formation, and pigmentary alteration.
In a recent report, a new standardized corticosteroid therapy protocol has been shown to reducethe recurrence of keloids and hypertrophic scars after excision. Intralesional TAC injection wasperformed after removal of the sutures and then once every 2 weeks (total of 5 treatments). Inaddition, patients were instructed to apply corticosteroid ointment twice daily for 6 months to thewounds after suture removal. Only 3 (14.3%) of 21 keloids and 1 (16.7%) of 6 hypertrophicscars recurred.[3]
Current and New Treatments
Current treatments for keloids and hypertrophic scars include intralesional IFN; 5-FU;doxorubicin; bleomycin; verapamil; retinoic acid; imiquimod 5% cream; tacrolimus; tamoxifen;botulinum toxin; TGF-beta3; rhIL-10; VEGF inhibitors; etanercept; mannose-6-phosphate
inhibitors (M6P); onion extract; the combination of hydrocortisone, silicon, and vitamin E; PDT;intense pulsed light (IPL); UVA-1; and narrowband UVB.
IFN therapy, including IFN alfa, IFN beta, and IFN gamma, has been demonstrated in in vitrostudies to reduce keloidal fibroblast production of collagen types I, III, and VI mRNA.
IFN alfa and IFN beta also reduce fibroblast production of glycosaminoglycans (GAGs), whichform the scaffolding for the deposition of dermal collagen. IFN gamma enhances GAGproduction.
-
8/13/2019 Keloid Resume
10/23
IFN alfa, IFN beta, and IFN gamma have been shown to increase collagenase activity. Studieshave shown that IFN gamma modulates a p53 apoptotic pathway by inducing apoptosis-relatedgenes. p53 is a protein synthesized following DNA damage. Once damage is repaired, p53 isdegraded. Mutations of this protein are believed to predispose cells to hyperproliferation,possibly resulting in keloid formation. In addition, p53 is a potent suppressor of interleukin (IL)6, a cytokine implicated in hyperproliferative and fibrotic conditions.
IFN injected into the suture line of keloid excision sites may be prophylactic for reducingrecurrences. Berman and Flores reported statistically significant fewer keloid recurrences in astudy of 124 keloid lesions after postoperative IFN alfa-2b injection treatment (5 million U, 1million U injected per cm of scar) into keloid excision sites (18%) versus excision alone (51.1%)and TAC treatment (58.4%).[4]
Tredget et al showed a significant increase in the rate of scar improvement compared with thecontrol period of time (P= .004) after injecting 9 patients with hypertrophic scars with 1 X106units of human recombinant IFN alfa-2b subcutaneously, daily for 7 days, and then 2 X106units administered 3 times per week for 24 weeks in total.[5] Scar assessment (P< .05) andscar volume (P< .05) also improved after 3 months of treatment. No recurrences were reported
after stopping IFN therapy.Conejo-Mir et al reported that 66% of keloids (n = 20) did not recur after 3 years of follow-upafter treating 30 keloids with ultrapulse carbon dioxide laser ablation followed by sublesionaland perilesional injections of 3 million IU of IFN alfa-2b 3 times per week.[6]
In a 2008 prospective study, Lee et al reported decreases in depth (81.6%, P= .005) andvolume (86.6%, P= .002) treating 20 keloids with a combination of intralesional TAC and IFNalfa-2b compared with only a nonsignificant improvement (P= .281 and P= .245, respectively)obtained in 20 keloids treated with TAC alone.[7]
Notably, however, several studies have failed to demonstrate the efficacy of IFN alfa-2b for thetreatment of keloids and hypertrophic scars, including a case series of 5 patients treated by
Wong et al,[8] a case series by al-Khawajah of 22 patients with keloids using lower doses of IFNalfa-2b than in prior studies,[9] and a prospective randomized clinical trial by Davison et al inwhich 50 patients with keloids received intraoperative intradermal injections of IFN alfa-2b at 10million U/mL or TAC at 40 mg/mL, both receiving an extra injection 1 week later.[10]
Hypertrophic scar intralesional injections of human recombinant IFN gamma at 200 mcg (6 X106U) per injection for 4 weeks have been reported by Pittet et al to be effective for relieving thesymptoms in 6 of 7 patients and decreases in redness, swelling, firmness, and lesion area in 7of 7 patients.[11]At week 16, the reappearance of symptoms was minimal in only 2 of 7 patientsand a small increase in the lesion area occurred in 4 of 7 patients, although these lesionsremained smaller than the original area.
5-Fluorouracil5-FU, a pyrimidine analogue with antimetabolite activity, inhibits fibroblastic proliferation intissue culture and is believed to reduce postoperative scarring by decreasing fibroblastproliferation. Its efficacy and safety have been reported when used as a monotherapy or whenused in combination with other drugs (eg TAC) for the treatment of other fibrosing conditions,including infantile digital fibromatosis, knuckle pads, rheumatoid nodules, and adverse foreignbody reaction and sarcoidal granulomatous complications after soft tissue filler injection. Some
-
8/13/2019 Keloid Resume
11/23
data suggest that 5-FU is effective in the treatment of hypertrophic scars and is somewhateffective in small keloids. Several studies have shown the effectiveness of 5-FU.
In a retrospective study of 1000 patients with hypertrophic scars and keloids over a 9-yearperiod, the most effective regimen was found to be 0.1 mL of TAC (10 mg/mL) and 0.9 mL of 5-FU (50 mg/mL) up to 3 times a week.
A total of 85% of keloids showed more than 50% improvement in an open study byKontochristopoulos et al in which 20 keloids were treated once weekly with intralesional 5-FU(50 mg/mL) for an average of 7 treatments, with a recurrence rate of 47% within 1 year of thetreatment. The Ki-67 proliferative index was significantly reduced (P= .0001) after treatment.[12]
Nanda and Reddy treated 28 patients with multiple keloids in a prospective, randomized,uncontrolled clinical trial with weekly intralesional injections of 5-FU at 50 mg/mL and reportedalmost 80% of the patients showing more than 50% improvement. Regression from theperiphery and flattening occurred in all patients. In 22 of 28 patients, the symptoms completelydisappeared, while the rest showed a good response. Decrease in size was reported in 70% ofthe patients.[13]
5-FU in combination with other therapies significantly increases the efficacy over singlemodalities.
In a double-blind randomized study, 40 patients with keloids or hypertrophic scars received 8weekly intralesional injections of TAC 10 mg/mL or a combination of TAC 4 mg/mL plus 5-FU 45mg/mL. At week 12, both groups showed improvement; however, the lesions in the TAC plus 5-FU group had significantly greater pliability and less erythema, height, length, and width (P