Intralesional interferon gamma treatment for keloids and hypertrophic scars

Comparing Combination Triamcinolone Acetonide and 5-Fluorouracil with Monotherapy Triamcinolone Acetonide or 5-Fluorouracil in the Treatment of Hypertrophic Scars: A Systematic Review and Meta-Analysis

BACKGROUND

Keloids and hypertrophic scars cause physical and psychosocial problems. A combination of 5-fluorouracil (5-FU) and triamcinolone acetonide (TAC) may enhance the treatment of pathologic scars, although the evidence base is limited. The authors compared the efficacy and complication rates of combination intralesional TAC and 5-FU with those of monotherapy intralesional TAC or 5-FU for the treatment of keloids and hypertrophic scars.

METHODS

Embase, MEDLINE, and CENTRAL were searched by two independent reviewers. The primary outcome was treatment efficacy (51% to 100% improvement). Study quality and risk of bias were assessed using the Cochrane risk of bias tool.

RESULTS

Of 277 articles screened, 13 studies were included, comprising 12 randomized control trials and one nonrandomized study. Six studies compared combination intralesional therapy versus monotherapy 5-FU, and nine studies compared combination intralesional therapy versus monotherapy TAC. The combined group demonstrated superior objective treatment efficacy compared with the monotherapy TAC group (OR, 3.45; 95% CI, 2.22 to 5.35; I 2 = 0%; P < 0.00001) and monotherapy 5-FU group (OR, 4.17; 95% CI, 2.21 to 7.87; I 2 = 0%; P < 0.0001). Telangiectasia was less frequent in combination therapy (OR, 0.24; 95% CI, 0.11 to 0.52; I 2 = 0%; P = 0.0003) compared with monotherapy TAC.

CONCLUSIONS

Combined intralesional TAC and 5-FU administration demonstrated superior treatment efficacy outcomes compared with monotherapy TAC or 5-FU. Patient-reported outcome measures should be incorporated in the design of future research to justify clinical recommendations.

CLINICAL RELEVANCE STATEMENT

Combined TAC and 5-FU has demonstrated superior treatment efficacy outcomes compared to monotherapy TAC or 5-FU in the treatment of hypertrophic scars and keloids.

Pharmacotherapy for Keloids and Hypertrophic Scars

Keloids (KD) and hypertrophic scars (HTS), which are quite raised and pigmented and have increased vascularization and cellularity, are formed due to the impaired healing process of cutaneous injuries in some individuals having family history and genetic factors. These scars decrease the quality of life (QOL) of patients greatly, due to the pain, itching, contracture, cosmetic problems, and so on, depending on the location of the scars. Treatment/prevention that will satisfy patients' QOL is still under development. In this article, we review pharmacotherapy for treating KD and HTS, including the prevention of postsurgical recurrence (especially KD). Pharmacotherapy involves monotherapy using a single drug and combination pharmacotherapy using multiple drugs, where drugs are administered orally, topically and/or through intralesional injection. In addition, pharmacotherapy for KD/HTS is sometimes combined with surgical excision and/or with physical therapy such as cryotherapy, laser therapy, radiotherapy including brachytherapy, and silicone gel/sheeting. The results regarding the clinical effectiveness of each mono-pharmacotherapy for KD/HTS are not always consistent but rather scattered among researchers. Multimodal combination pharmacotherapy that targets multiple sites simultaneously is more effective than mono-pharmacotherapy. The literature was searched using PubMed, Google Scholar, and Online search engines.

Wound healing, scarring and management

Understanding wound healing is imperative for the dermatological physician to optimize surgical outcomes. Poor healing may result in negative functional, cosmetic and psychological sequelae. This review briefly outlines the physiology of wound healing, with a view to improving the management of wounds and scars, and minimizing the long-term scarring complications.

Non-Invasive and Surgical Modalities for Scar Management: A Clinical Algorithm

Scars can lead to aesthetic and functional impairments. The treatment of scars requires meticulous planning and an individually adapted therapeutic strategy. A conceptual algorithm for scar treatment makes everyday clinical work easier for the practitioner and offers more safety for the patient. Based on a retrospective analysis of 1427 patients who presented for treatment of a variety of scars, we developed an algorithm for scar management and treatment. The treatments are presented using case descriptions. Additionally, an electronic search of MEDLINE, EMBASE, and ClinicalTrials.gov databases was performed utilizing combinations of relevant medical subject headings for "scar treatment", "hypertrophic scar treatment" and "keloid treatment". Reference lists of relevant articles and reviews were hand-searched for additional reports. Observed outcomes included: conservative scar therapy, minimally invasive scar therapy, and surgical scar therapy using local, regional and free flaps. With this work, we provide an algorithm for safe scar treatment. For better understanding, we have described a clinical case for each algorithm modality.

The safety and efficacy of intralesional triamcinolone acetonide for keloids and hypertrophic scars: A systematic review and meta-analysis

BACKGROUND

Triamcinolone acetonide (TAC) is widely used for hypertrophic scars and keloids; however, TAC has variable efficacy and safety in different individuals.

PURPOSE

To evaluate the efficacy and safety of intralesional TAC for treatment of hypertrophic scars and keloids.

DATA SOURCES

Searches of PubMed, EMBASE, the Cochrane Library, and ClinicalTrials.gov prior to 25 March 2020.

STUDY SELECTION

Randomized controlled trials in English that compared TAC with a placebo or other medications that are commonly used for intralesional injection in hypertrophic scars and keloids.

DATA EXTRACTION

Primary outcomes were reduction in scar height, vascularity, pliability, pigmentation, total scores on the Vancouver Scar Scale (VSS) or patient and observer scar assessment scale (POSAS), telangiectasia, and skin atrophy. Secondary outcomes included overall scar improvement.

DATA SYNTHESIS

Fifteen trials met the inclusion criteria. In the short term, TAC was associated with a significant improvement in vascularity (MD: -0.22, 95% CI: -0.42 to -0.02) and pliability (MD: -0.25, 95% CI: -0.44 to -0.06) compared to verapamil. In the medium term, compared to TAC, 5-FU showed a significant improvement in scar height (SMD: 0.95, 95% CI: 0.15-1.75), while TAC led to a significant improvement in vascularity compared to 5-FU (MD: -0.45, 95% CI: -0.76 to -0.14). Compared to TAC, TAC+5-FU showed a significant improvement in pliability (SMD: 0.98, 95% CI: 0.17-1.78) and pigmentation (MD: 0.45, 95% CI: 0.12-0.78). Botulinum toxin type A resulted in significantly better pliability (SMD: 1.99, 95% CI: 0.98-3.00) compared to TAC. In the long term, compared to TAC, 5-FU led to a significant improvement in scar height (MD: 0.55, 95% CI: 0.17-0.93), but significantly less vascularity (MD: -0.35, 95% CI: -0.65 to -0.05). Compared to TAC, TAC+5-FU produced a significant improvement in scar height (MD: 1.50, 95% CI: 1.12-1.88), pliability (MD: 0.45, 95% CI: 0.10-0.80), and pigmentation (MD: 0.55, 95% CI: 0.24-0.86).

CONCLUSION

TAC may be beneficial for the short-term treatment of hypertrophic scars and keloids; however, 5-FU, 5-FU+TAC, and verapamil may produce superior results for medium- and long-term treatments. TAC injections at concentrations of 20 mg/ml or 40 mg/ml are more likely to result in skin atrophy compared to 5-FU or verapamil, and are more likely to cause telangiectasia than 5-FU, 5-FU+TAC, or bleomycin.

Nonsurgical Management of Hypertrophic Scars: Evidence-Based Therapies, Standard Practices, and Emerging Methods

Hypertrophic scars, resulting from alterations in the normal processes of cutaneous wound healing, are characterized by proliferation of dermal tissue with excessive deposition of fibroblast-derived extracellular matrix proteins, especially collagen, over long periods, and by persistent inflammation and fibrosis. Hypertrophic scars are among the most common and frustrating problems after injury. As current aesthetic surgical techniques become more standardized and results more predictable, a fine scar may be the demarcating line between acceptable and unacceptable aesthetic results. However, hypertrophic scars remain notoriously difficult to eradicate because of the high recurrence rates and the incidence of side effects associated with available treatment methods. This review explores the various treatment methods for hypertrophic scarring described in the literature including evidence-based therapies, standard practices, and emerging methods, attempting to distinguish those with clearly proven efficiency from anecdotal reports about therapies of doubtful benefits while trying to differentiate between prophylactic measures and actual treatment methods. Unfortunately, the distinction between hypertrophic scar treatments and keloid treatments is not obvious in most reports, making it difficult to assess the efficacy of hypertrophic scar treatment.

Current and upcoming therapies to modulate skin scarring and fibrosis

Skin is the largest organ of the human body. Being the interface between the body and the outer environment, makes it susceptible to physical injury. To maintain life, nature has endowed skin with a fast healing response that invariably ends in the formation of scar at the wounded dermal area. In many cases, skin remodelling may be impaired, leading to local hypertrophic scars or keloids. One should also consider that the scarring process is part of the wound healing response, which always starts with inflammation. Thus, scarring can also be induced in the dermis, in the absence of an actual wound, during chronic inflammatory processes. Considering the significant portion of the population that is subject to abnormal scarring, this review critically discusses the state-of-the-art and upcoming therapies in skin scarring and fibrosis.

Novel pharmacotherapy for burn wounds: what are the advancements

INTRODUCTION

The prognosis for severe burns has improved significantly over the past 50 years. Meanwhile, burns have become an affliction mainly affecting the less well-developed regions of the world. Early excision and skin grafting has led to major improvements in therapeutic outcomes.

AREAS COVERED

The purpose of this article is to survey the use of pharmacotherapy to treat different pathophysiological complications of burn injury. The author, herein, discusses the use of drug treatments for a number of systemic metabolic disturbances including hyperglycemia, elevated catabolism, and gluconeogenesis.

EXPERT OPINION

Advancements in personalized and molecular medicine will make an impact on burn therapy. Similarities between severe burns and other critically ill patients will lead to cross-fertilization between different medical specialties. Furthermore, advances in stem cells and tissue regeneration will lead to improved healing and less lifelong disability. Indeed, research in new drug therapy for burns is actively progressing for many different complications.

Treatment of keloid scars with intralesional triamcinolone and 5-fluorouracil injections - a randomized controlled trial

Keloids have high recurrence rates. Current first-line therapy is triamcinolone (TAC) injection, but it has been suggested that approximately 50% of keloids are steroid resistant. We compared the efficacy of intralesional 5-fluorouracil (5-FU) and triamcinalone injections in a double-blind randomized controlled trial. Forty-three patients with 50 keloid scars were treated with either intralesional TAC or 5-FU-injections over 6 months. There was no statistically significant difference in the remission rate at 6 months between the 5-FU and TAC groups (46% vs 60%, respectively). Local adverse effects were higher in the TAC group compared to the 5-FU group. Occurrence of skin atrophy in TAC group was 44% and in the 5-FU group 8% (p < 0.05). Also the occurrence of telangiectasia in the TAC group was 50% and in the 5-FU 21% (p < 0.05). Vascularity of the keloids, assessed by spectral imaging and immunohistochemical staining for blood vessels, after treatment decreased in the TAC group, but not in the 5-FU group (p < 0.05). Fibroblast proliferation evaluated by Ki-67 staining significantly decreased in the TAC group (p < 0.05) but increased in the 5-FU group (p < 0.05). TAC and 5-FU injections did not differ in their clinical effectivity in this randomized study, but 5-FU injections lead to increased proliferation rate and did not affect vascular density in histological assessment. Due to the greater number of adverse effects observed after TAC treatment, 5-FU injections may be preferable for cosmetically sensitive skin areas.

Current Therapeutic Approach to Hypertrophic Scars

Abnormal scarring and its accompanying esthetic, functional, and psychological sequelae still pose significant challe nges. To date, there is no satisfactory prevention or treatment option for hypertrophic scars (HSs), which is mostly due to not completely comprehending the mechanisms underlying their formation. That is why the apprehension of regular and controlled physiological processes of scar formation is of utmost importance when facing hypertrophic scarring, its pathophysiology, prevention, and therapeutic approach. When treating HSs and choosing the best treatment and prevention modality, physicians can choose from a plethora of therapeutic options and many commercially available products, among which currently there is no efficient option that can successfully overcome impaired skin healing. This article reviews current therapeutic approach and emerging therapeutic strategies for the management of HSs, which should be individualized, based on an evaluation of the scar itself, patients’ expectations, and practical, evidence-based guidelines. Clinicians are encouraged to combine various prevention and treatment modalities where combination therapy that includes steroid injections, 5-fluorouracil, and pulsed-dye laser seems to be the most effective. On the other hand, the current therapeutic options are usually empirical and their results are unreliable and unpredictable. Therefore, there is an unmet need for an effective, targeted therapy and prevention, which would be based on an action or a modulation of a particular factor with clarified mechanism of action that has a beneficial effect on wound healing. As the extracellular matrix has a crucial role in cellular and extracellular events that lead to pathological scarring, targeting its components mostly by regulating bone morphogenetic proteins may throw up new therapeutic approach for reduction or prevention of HSs with functionally and cosmetically acceptable outcome.

In Situ Cytokine Expression and Morphometric Evaluation of Total Collagen and Collagens Type I and Type III in Keloid Scars

Keloids are characterized by excessive collagen deposition and growth beyond the edges of the initial injury, and cytokines may be related to their formation. The objective of this study was to evaluate the collagen fibers, analyze in situ expression of cytokines in keloid lesions, and compare to the control group. Results showed that there was a predominance of women and nonwhite and direct black ancestry. Keloid showed a significant increase in total and type III collagen. Significantly, the expression of mRNA for TGF-β in keloid was increased, the expressions of IFN-γ, IFN-γR1, and IL-10 were lower, and IFN-γR1 and TNF-α had no statistical difference. Correlations between collagen type III and TGF-β mRNA expression were positive and significant, IFN-γ, IFN-γR1, and IL-10 were negative and significant, and TNF-α showed no statistical difference. We conclude that there was a significant increase of total collagen in keloid and predominance of collagen type III compared to the controls, showing keloid as an immature lesion. There is a significant increase in TGF-β mRNA in keloid lesions, and a significant decrease in IFN-γ and IL-10, suggesting that these cytokines are related to keloid lesions.

A Comparison of Gene Expression of Decorin and MMP13 in Hypertrophic Scars Treated With Calcium Channel Blocker, Steroid, and Interferon: A Human-Scar-Carrying Animal Model Study

BACKGROUND

The formation of hypertrophic scaring (HSc) is an abnormal wound-healing response. In a previous study, an animal model with human scar tissue implanted into nude mice (BALB/c) has been successfully established. The effects of verapamil as well as combination therapy with verapamil and kenacort have been studied and compared.

OBJECTIVE

To treat persistent hypertrophic scars, local injection of drugs composed of steroids, calcium channel blockers (CCBs), and interferon might be a good method. What is the best dose of the regimen and what are the mechanisms are also a worthwhile study.

MATERIALS AND METHODS

Scar specimens were harvested from patients with HSc or Keloid resulting from burn injury, and then implanted to BALB/c-nu nude mice for 4 weeks. Before implantation, the specimen was either injected with or without drugs such as steroids (kenacort), CCBs (verapamil), and interferons (INFα2b), respectively. After the removal of implants, quantitative gene expressions of decorin and collagenase (MMP13) were measured using a real-time polymerase chain reaction to detect their mRNAs. Two way-ANOVA and Post Hoc were used for statistical analysis using the software SPSS 15.0.

RESULTS

All drug-treated groups increased the expressions of decorin and MMP13 in comparison with those in noninjected group (p < .001) in a dose-dependent manner. Comparing equal amounts of individual drugs, gene expression of decorin was increased with increasing injection amount, and the best result in low amount of injection (0.02 mL of each) was shown in the group injected with INFα2b followed by kenacort and verapamil. However, the results were changed while injection amount was up to 0.04 mL and the strongest decorin gene expression was found in kenacort injection. Regarding MMP-13 expression, low-amount injection (0.02 mL) of INFα2b has strongest gene expression followed by kenacort and verapamil, but in the large-amount regimes (0.04 mL), verapamil had strongest gene expression followed by INFα2b and kenacort.

CONCLUSION

This study showed that the kenacort, verapamil, and INFα2b all inhibited HSc in a dose-dependent manner through the evidence of gene expression of decorin and MMP13. In comparison with the injections between small amounts of drugs, INFα2b potentiated the strongest decorin and MMP13 expression. On the contrary, among the large-amount injection regimes, kenacrot was more effective on decorin expression as verapamil to MMP13 expression. To decrease side effects from the drugs and produce promising results for the clinical practice, it is suggested to maintain the dose of INFα2b along with an increased dose of verapamil for HSc improvement.

Effects of DMSO on a rabbit ear hypertrophic scar model: A controlled randomized experimental study

Dimethyl sulfoxide (DMSO) is an anti-inflammatory, antibacterial, analgesic drug widely used to treat several diseases as reported in the literature. It has a detractive effect on collagen deposition in the abnormal tissue. This study aimed to investigate the possible therapeutic effects of DMSO on hypertrophic scar formation in rabbits. Twenty-four New Zealand male albino rabbits were randomly divided into four groups: control, sham, DMSO, and TRA (triamcinolone acetonide). Except the control group, punch biopsy defects were created on each animal's right ear. Following the hypertrophic scar formation on day 28, intralesional DMSO and triamcinolone acetonide were administered once a week for 4 weeks into these scars of the DMSO and TRA groups, respectively. No therapeutic agent was administered to the control and sham groups. One week after the last injection, ear samples were collected for histopathological, immunohistochemical, and real-time polymerase chain reaction gene expression analyses. Histopathological examination revealed that the epithelium in the DMSO group was thicker than that in the control and TRA groups, but thinner than that in the sham group. Connective tissue thickness and vascularity level of the sham group were higher than those of the control, DMSO, and TRA groups. The collagen type I immunoreactivity level of the sham and TRA groups was higher than those of the control and DMSO groups. The collagen type III immunoreactivity level was higher in the sham group than in all other groups. Collagen type I/type III immunoreactivity ratios were lower in the DMSO group. The alignment of collagen fibers was normal in the DMSO group, but was irregular in the sham and TRA groups. The collagen type I gene expression levels of the DMSO and TRA groups were lower than that of the sham group. Collagen type III and IFN-γ mRNA expression levels were almost similar among the groups. TGF-1β mRNA expression levels were higher in the DMSO and TRA groups than in the control and sham groups. On the basis of the results, it can be concluded that intralesional administration of DMSO decreases hypertrophic scar formation easily and safely.

Intralesional injection treatment of hypertrophic scars and keloids: a systematic review regarding outcomes

Background

The aim of this review was to explore the existing body of literature focusing on the intralesional treatments of keloids and hypertrophic scars.

Methods

A comprehensive systematic review of related articles was conducted across multiple databases. Article selection was limited to those published in the English language between 1950 and 2014. Search terms for the on-line research were “scar(s),” “keloid(s),” “hypertrophic,” “injection,” “intralesional,” and “treatment”.

Results

The initial search returned 2548 published articles. After full text review, the final search yielded 11 articles that met inclusion criteria. A total of 14 patient samples in 11 articles were collected. The most frequent intralesional injection treatment studied was triamcinolone (n = 5), followed by bleomycin (n = 3), 5-fluorouracil (n = 2), verapamil (n = 2), cryosurgery, and collagenase. The scar height reduction for all but one study was demonstrated, with acceptable complication and recurrence rate. Only three articles reported a follow-up period longer than 18 months, and only two studies used standardized outcome criteria with a quantitative scale.

Conclusions

Although many treatment options have already been described in the literature, there is no universally accepted treatment resulting in permanent hypertrophic or keloid scar ablation. The lack of adequately long-term powered randomized controlled trials does not permit to establish definitive conclusions with implications for routine clinical practice.

Level of evidence

III/Therapeutic

In vivo early intervention and the therapeutic effects of 20(s)-ginsenoside rg3 on hypertrophic scar formation

BACKGROUND

Intra-lesional injections of corticosteroids, interferon, and chemotherapeutic drugs are currently the most popular treatments of hypertrophic scar formation. However, these drugs can only be used after HS is formed, and not during the inflammatory phase of wound healing, which regulates the HS forming process.

OBJECTIVE

To investigate a new, effective, combining therapeutic and safe drug for early intervention and treatment for hypertrophic scars.

METHODS

Cell viability assay and flow cytometric analysis were studied in vitro. Animal studies were done to investigate the combining therapeutic effects of 20(S)-ginsenoside Rg3 (Rg3) on the inflammatory phase of wound healing and HS formation.

RESULTS

In vitro studies showed that Rg3 can inhibit HS fibroblasts proliferation and induce HSF apoptosis in a concentration-dependent manner. In vivo studies demonstrated that Rg3 can limit the exaggerated inflammation, and do not delay the wound healing process, which indicates that Rg3 could be used as an early intervention to reduce HS formation. Topical injection of 4 mg/mL Rg3 can reduce HS formation by 34%. Histological and molecular studies revealed that Rg3 injection inhibits fibroblasts proliferation thus reduced the accumulation of collagen fibers, and down-regulates VEGF expression in the HS tissue.

CONCLUSION

Rg3 can be employed as an early intervention and a combining therapeutic drug to reduce inflammation and HS formation as well.

Recent developments in the use of intralesional injections keloid treatment

Keloid scars are often considered aesthetically unattractive and frustrating problems that occur following injuries. They cause functional and cosmetic deformities, displeasure, itching, pain, and psychological stress and possibly affect joint movement. The combination of these factors ultimately results in a compromised quality of life and diminished functional performance. Various methods have been implemented to improve keloid scars using both surgical and non-surgical approaches. However, it has proven to be a challenge to identify a universal treatment that can deliver optimal results for all types of scars. Through a PubMed search, we explored most of the literature that is available about the intralesional injection treatment of hypertrophic scars and keloids and highlights both current (corticosteroid, 5-fluorouracil, bleomycin, interferon, cryotherapy and verapamil) and future treatments (interleukin-10 and botulinum toxin type A). The reference lists of retrieved articles were also analysed. Information was gathered about the mechanism of each injection treatment, its benefits and associated adverse reactions, and possible strategies to address adverse reactions to provide reliable guidelines for determining the optimal treatment for particular types of keloid scars. This article will benefit practitioners by outlining evidence-based treatment strategies using intralesional injections for patients with hypertrophic scars and keloids.

Up-to-date approach to manage keloids and hypertrophic scars: a useful guide

Keloids and hypertrophic scars occur anywhere from 30 to 90% of patients, and are characterized by pathologically excessive dermal fibrosis and aberrant wound healing. Both entities have different clinical and histochemical characteristics, and unfortunately still represent a great challenge for clinicians due to lack of efficacious treatments. Current advances in molecular biology and genetics reveal new preventive and therapeutical options which represent a hope to manage this highly prevalent, chronic and disabling problem, with long-term beneficial outcomes and improvement of quality of life. While we wait for these translational clinical products to be marketed, however, it is imperative to know the basics of the currently existing wide array of strategies to deal with excessive scars: from the classical corticotherapy, to the most recent botulinum toxin and lasers. The main aim of this review paper is to offer a useful up-to-date guideline to prevent and treat keloids and hypertrophic scars.

New molecular medicine-based scar management strategies

Keloids and hypertrophic scars are prevalent disabling conditions with still suboptimal treatments. Basic science and molecular-based medicine research have contributed to unravel new bench-to-bedside scar therapies and to dissect the complex signalling pathways involved. Peptides such as the transforming growth factor beta (TGF-β) superfamily, with Smads, Ski, SnoN, Fussels, endoglin, DS-Sily, Cav-1p, AZX100, thymosin-β4 and other related molecules may emerge as targets to prevent and treat keloids and hypertrophic scars. The aim of this review is to describe the basic complexity of these new molecular scar management strategies and point out new fibrosis research lines.

Pathological niche environment transforms dermal stem cells to keloid stem cells: a hypothesis of keloid formation and development

Keloid is a disease that is difficult to cure because of its high recurrence rate after chemotherapy or radiotherapy, therefore it is considered as a benign skin tumor. Tumor stem cells are proposed as the source for tumor development and post-therapy recurrence. Interestingly, keloid stem cells have also been discovered, which share some characters with those of skin progenitor cells. Keloid patients possess specific diathesis including genetic predisposition and gene mutation, abnormal levels of hormones, growth factors and cytokines, and strong inflammatory response. This article reviews related literatures and hypothesizes that keloid stem cells might be transformed from normal dermal progenitor cells in the pathological niche of keloid tissues. These keloid stem cells are highly self-renewal and drug resistant, and can sustain themselves by asymmetric division, and continually generate new keloid cells to replenish the cells killed by drugs or radiation, thus leading to over growth of keloid and high post-therapy recurrence rate.

Detrimental dermal wound healing: what can we learn from the oral mucosa?

Wounds in adults are frequently accompanied by scar formation. This scar can become fibrotic due to an imbalance between extracellular matrix (ECM) synthesis and ECM degradation. Oral mucosal wounds, however, heal in an accelerated fashion, displaying minimal scar formation. The exact mechanisms of scarless oral healing are yet to be revealed. This review highlights possible mechanisms involved in the difference between scar-forming dermal vs. scarless oral mucosal wound healing. Differences were found in expression of ECM components, such as procollagen I and tenascin-C. Oral wounds contained fewer immune mediators, blood vessels, and profibrotic mediators but had more bone marrow-derived cells, a higher reepithelialization rate, and faster proliferation of fibroblasts compared with dermal wounds. These results form a basis for further research that should be focused on the relations among ECM, immune cells, growth factors, and fibroblast phenotypes, as understanding scarless oral mucosal healing may ultimately lead to novel therapeutic strategies to prevent fibrotic scars.

Identification of steroid sensitive responders versus non-responders in the treatment of keloid disease

Intralesional corticosteroid injection is a well-recognised treatment modality for keloid disease (KD). Approximately 50% of KD cases are considered non-responders (or steroid resistant) with no consensus or indicators in detecting steroid-sensitive cases. In view of the undesirable side effects, uncertainty in timing and regularity of steroid treatment, we planned to identify responders and non-responders to target treatment more effectively. A scar injection proforma was developed capturing a detailed history focusing on symptoms and signs (redness, appearance, contour, texture, distortion and severity) associated with KD. The cause, site, number of keloid scars and scar recurrence were recorded as the lesions were injected on a monthly basis. A detailed description of response to steroid injection was documented and photographs were taken. Demographic data were collected on 65 patients (11 to 74 years with mean age 34.7 years, 60% were females, 50% were Caucasian). 77% (n = 50) were classified as steroid responders and showed improvement in symptoms and signs within 3 months. There was a statistically significant correlation between patients with higher contour scores of KD prior to treatment (p = 0.013) and frequency of injections (p = 0.003). Thus, the odds of being a responder were greater for patients with more than one injection and with higher contour scores. This preliminary case series has provided early evidence in enabling identification of steroid responders versus non-responders within a 3-month period. Selection of KD non-responders to steroid treatment can avoid potentially painful injection, its subsequent side effects and unnecessary continuation of redundant therapy and follow-up.

Eradication of keloids: Surgical excision followed by a single injection of intralesional 5-fluorouracil and botulinum toxin

BACKGROUND

Keloids may complicate wound healing secondary to trauma, inflammation or surgical incision. Although various treatment modalities have been used with variable degrees of success, overall recurrence rates have remained unacceptably high.

METHODS

The present study involved 80 patients with keloids of at least one-years' duration. Following total surgical excision of the keloid, a single dose of 5-fluorouracil was injected into the edges of the healing wound on postoperative day 9 together with botulinum toxin. The concentration of 5-fluorouracil used was 50 mg/mL and approximately 0.4 mL was infiltrated per cm of wound tissue, with the total dose <500 mg. The concentration of botulinum toxin was 50 IU/mL with the total dose <140 IU.

RESULTS

Patients were followed-up for 17 to 24 months and a recurrence rate of 3.75% was found, which was significantly lower than in previously reported studies using other therapeutic modalities.

CONCLUSION

The author recommends that this treatment be routinely applied to all keloids because it is significantly more effective than those described by other authors.

Clinical analysis of auricular benign masses

Background and Objectives

Auricular masses are growths on the outer ear that have not been well characterized clinically. We assessed the clinical nature and treatment of auricular benign masses in patients at our institution.

Subjects and Methods

We retrospectively identified 63 patients with auricular benign masses who underwent excision and biopsy from May 1970 to April 2011. We determined the site, cause, size, pathology and postoperative results of these auricular masses.

Results

Auricular benign masses occurred most commonly on the lobule (44.4%), followed by the tragus (20.6%), crus of helix (11.1%), triangular fossa (6.3%), crus of antihelix-antitragus (3.1%) and scapha (1.5%). Pathologically, the most common type of auricular mass was epidermal cysts (25.3%), followed by hypertrophic scar (12.6%), fibrous tissue-accessory ear (9.5%), chronic inflammation-nevus (7.9%), keloid (6.3%), hemangioma (4.7%), and skin tag-seborrheic keratosis (3.1%).

Conclusions

The most common site of auricular benign masses is the lobule and most common pathology is an epidermal cyst.

ROLE OF PHENERGAN IN ABNORMAL SCARS AND KELOIDS

Hypertrophic scar and keloids have affected patients and frustrated physicians for centuries. Hypertrophic scar (HSc) and keloids are a major problem for patients who survive extensive thermal and traumatic skin injuries. HSc and other fibroproliferative disorders are associated with excessive accumulation of collagen and extracellular matrix proteins due to an imbalance between synthesis and degradation. The therapeutic management of hypertrophic scars and keloids include occlusive dressings, compression therapy, intralesional corticosteroid injections, cryosurgery, excision, radiation therapy, laser therapy, interferon therapy and other promising lesser known therapies directed at collagen synthesis. In this study we investigated the effect of phenergan (promethazine hydrochloride) as one of the most potent histamine antagonists on cell proliferation, DNA synthesis and collagen production in fibroblast isolated from human post burn hypertrophic scar, keloids and normal skin. The proliferation of normal skin fibroblast was slightly decreased but hypertrophic scar and keloids showed significant (p<0.001) level of decrease after 72 hours of phenergan (750 μM) treatment. The results of DNA synthesis also significantly (p<0.001) decreased in hypertrophic scar and keloid fibroblasts. Phenergan (1.5 mM) decreased the collagen synthesis upto 61% and 66% in HSc and keloids in comparison to normal skin fibroblast, which showed reduction of 38% after 72 hours. Improved understanding of such regulatory mechanisms may eventually be of therapeutic significance in the control of hypertrophic scar and keloids.

Biological agents for controlling excessive scarring

The potential of various biological agents to reduce or prevent excessive scar formation has now been evaluated in numerous in-vitro studies, experimental animal models and preliminary clinical trials, in some cases with particularly promising results. Perhaps prominent among this group of biological agents, and, to some degree, possibly representing marketed compounds already being used 'off label' to manage excessive scarring, are the tumor necrosis factor alpha antagonist etanercept, and immune-response modifiers such as IFNalpha2b and imiquimod. Additional assessment of these novel agents is now justified with a view to reducing or preventing hypertrophic scars, keloid scars and the recurrence of post-excision keloid lesions.

The emerging role of antineoplastic agents in the treatment of keloids and hypertrophic scars: a review

The management of keloids and hypertrophic scars continues to challenge health-care providers. Though both forms of pathologic scarring are distinct entities at the macro and microscopic level, their etiologies and treatment are often similar. Potential treatment approaches are progressing, and combinations of treatment options have been proposed in the literature with promising outcomes. The treatment evolution has reached a level where molecular therapeutic modalities are being investigated. Currently, no gold standard treatment exists. Overall success rates and patient satisfaction seem to be slowly climbing, but additional investigational studies must continue to be performed. Several studies have investigated antineoplastic agents, and there seems to be a marked improvement in rates of recurrence, patient satisfaction, and overall quality of scar when these agents are used. Intralesional injection and/or wound irrigation with interferon-a2b, interferon-g, mitomycin-C, bleomycin, or 5-fluorouracil seems to have a positive effect on the reduction of pathologic scars. There is mounting evidence that these drugs used alone or in combination therapy, have the potential to be an integral part of the treatment paradigm for hypertrophic scars and keloids.

Scar and contracture: biological principles

Dysregulated wound healing and pathologic fibrosis cause abnormal scarring, leading to poor functional and aesthetic results in hand burns. Understanding the underlying biologic mechanisms involved allows the hand surgeon to better address these issues, and suggests new avenues of research to improve patient outcomes. In this article, the authors review the biology of scar and contracture by focusing on potential causes of abnormal wound healing, including depth of injury, cytokines, cells, the immune system, and extracellular matrix, and explore therapeutic measures designed to target the various biologic causes of poor scar.

Hypertrophic scars and keloids--a review of their pathophysiology, risk factors, and therapeutic management

BACKGROUND

Hypertrophic scars and keloids result from an abnormal fibrous wound healing process in which tissue repair and regeneration-regulating mechanism control is lost. These abnormal fibrous growths present a major therapeutic dilemma and challenge to the plastic surgeon because they are disfiguring and frequently recur.

OBJECTIVE

To provide updated clinical and experimental information on hypertrophic scars and keloids so that physicians can better understand and properly treat such lesions.

METHODS

A Medline literature search was performed for relevant publications and for diverse strategies for management of hypertrophic scars and keloids.

CONCLUSION

The growing understanding of the molecular processes of normal and abnormal wound healing is promising for discovery of novel approaches for the management of hypertrophic scars and keloids. Although optimal treatment of these lesions remains undefined, successful healing can be achieved only with combined multidisciplinary therapeutic regimens.

Prevention and management of hypertrophic scars and keloids after burns in children

Hypertrophic scars and keloids are challenging to manage, particularly as sequelae of burns in children in whom the psychologic burden and skin characteristics differ substantially from adults. Prevention of hypertrophic scars and keloids after burns is currently the best strategy in their management to avoid permanent functional and aesthetical alterations. Several actions can be taken to prevent their occurrence, including parental and children education regarding handling sources of fire and flammable materials, among others. Combination of therapies is the mainstay of current burn scar management, including surgical reconstruction, pressure therapy, silicon gels and sheets, and temporary garments. Other adjuvant therapies such as topical imiquimod, tacrolimus, and retinoids, as well as intralesional corticosteroids, 5-fluorouracil, interferons, and bleomycin, have been used with relative success. Cryosurgery and lasers have also been reported as alternatives. Newer treatments aimed at molecular targets such as cytokines, growth factors, and gene therapy, currently in developing stages, are considered the future of the treatment of postburn hypertrophic scars and keloids in children.

Improvement in postburn hypertrophic scar after treatment with IFN-alpha2b is associated with decreased fibrocytes

Hypertrophic scar (HTS) following thermal injury is a dermal fibroproliferative disorder that leads to considerable morbidity. Previous clinical studies from our laboratory have suggested that interferon-alpha2b (IFN-alpha2b) improves scar quality as a result of suppression of fibroblast functions. Fibrocytes, which constitute a unique cell population, have recently been reported to contribute to wound healing and to a variety of fibrotic conditions, including HTS. Therefore, we hypothesize that improvement of scar in HTS patients after IFN-alpha2b treatment may be associated with a decreased number of fibrocytes or altered fibrocyte function. Using flow cytometry, immunofluorescent staining, and confocal microscopy, we demonstrate here that the marker protein leukocyte-specific protein 1 (LSP1) is stably expressed by fibrocytes for at least 2 months, whereas other potential fibrocyte markers, such as CD34 and CD45, gradually disappear. Using dual staining immunohistochemistry for LSP1 and procollagen, we demonstrated a significant reduction in numbers of fibrocytes in HTS tissue from patients after treatment with systemic IFN-alpha2b. IFN-alpha2b was shown to abolish fibrocyte differentiation from peripheral blood mononuclear cells (PBMCs) in vitro in a dose-dependent fashion. In addition, IFN-alpha2b inhibits proliferation of fibrocytes and T lymphocytes and reduces transforming growth factor-beta (TGF-beta)-mediated alpha-smooth muscle actin (alpha-SMA) expression in fibrocytes. Taken together with our previous study in which we showed that fibrocytes could indirectly regulate dermal fibroblasts in burn patients, the present study suggests that the improvement of scar quality in HTS patients after IFN-alpha2b treatment is associated with decreased numbers and activities of fibrocytes.

The effects of onion extract on hypertrophic and keloid scars

OBJECTIVE

To evaluate the therapeutic activity of topical onion extract in gel form on hypertrophic and keloid scars, focusing on problems such as elevation, redness, hardness, itching and pain.

METHOD

This comparative prospective study assigned 60 patients to three groups. Group I was treated with onion extract alone, group 2 with silicon gel sheet alone and 3 group with a combination of onion extract and silicon gel sheet.

RESULTS

In the group comparisons, a significant difference was observed at the end of six months in the colour parameter between group I and group 2 and in the height parameter between group I and group 3 (ANOVA post-hoc Tukey's test, p<0.01 and p<0.05 respectively). The onion extract was more effective in relation to scar colour, while the silicon gel sheet was superior in decreasing the height of scar (paired sample t-test, p<0.001). In addition, the most effective therapeutic results were obtained when the silicon gel sheet treatment was combined with onion extract in group 3.

CONCLUSION

Onion extract improved hypertrophic and keloids scars via multiple mechanisms. However, it was statistically ineffective in improving scar height and itching. For this reason, onion extract therapy should be used in combination with an occlusive silicon dressing to achieve a satisfying decrease in scar height.

Nonsurgical management of hypertrophic scars: evidence-based therapies, standard practices, and emerging methods

Hypertrophic scars, resulting from alterations in the normal processes of cutaneous wound healing, are characterized by proliferation of dermal tissue with excessive deposition of fibroblast-derived extracellular matrix proteins, especially collagen, over long periods, and by persistent inflammation and fibrosis. Hypertrophic scars are among the most common and frustrating problems after injury. As current aesthetic surgical techniques become more standardized and results more predictable, a fine scar may be the demarcating line between acceptable and unacceptable aesthetic results. However, hypertrophic scars remain notoriously difficult to eradicate because of the high recurrence rates and the incidence of side effects associated with available treatment methods. This review explores the various treatment methods for hypertrophic scarring described in the literature including evidence-based therapies, standard practices, and emerging methods, attempting to distinguish those with clearly proven efficiency from anecdotal reports about therapies of doubtful benefits while trying to differentiate between prophylactic measures and actual treatment methods. Unfortunately, the distinction between hypertrophic scar treatments and keloid treatments is not obvious in most reports, making it difficult to assess the efficacy of hypertrophic scar treatment.

Levels of evidence for the treatment of keloid disease

INTRODUCTION

Keloid disease presents a significant burden for patients and a significant therapeutic challenge for clinicians. Multiple treatments have been proposed, but with the increasing drive towards effective use of resources, therapeutic options need to be evaluated in terms of the levels of evidence supporting their use.

AIM

To retrieve and review the primary clinical studies evaluating keloid disease therapy over the last 25 years and assign levels of evidence for the treatment modalities evaluated.

METHOD

A Medline search was conducted to identify all primary clinical studies evaluating the treatment of keloid disease, published in English since 1980 (excluding single case reports). Studies were assigned a level of evidence (LOE-1, highest quality to LOE-5, lowest) adapted from the Oxford Centre for Evidence-based Medicine.

RESULTS

13 (12%) of 112 studies retrieved were assigned LOE-2, 99 (88%) assigned LOE-4. There were no LOE-1 studies. Ten of the LOE-2 studies evaluated silicone-based therapy or laser therapy. Most studies evaluating steroids, cryosurgery, laser therapy and post-surgical adjuvant therapy provide level 4 evidence.

CONCLUSION

High quality research in evaluating keloid therapy is lacking. There is a definite need for well designed and properly reported randomised controlled trials, to provide clinicians with a sound body of evidence on which to inform decision making.

Off-label uses of biologics in dermatology: Interferon and intravenous immunoglobulin (Part 1 of 2)

The introduction of a number of biologic therapies into the market has revolutionized the practice of dermatology. These therapies include interferons, intravenous immunoglobulin, infliximab, adalimumab, etanercept, efalizumab, alefacept, and rituximab. Most dermatologists are familiar with the Food and Drug Administration-approved indications of these medications. However, numerous off-label uses have evolved. As part 1 of a 2-part series, this article will review the literature regarding the off-label uses of the interferons and intravenous immunoglobulin in dermatology.

Treatment of Keloids and Hypertrophic Scars

Management of hypertrophic scars and keloids has advanced from crude, invasive methods such as gross excision and radiation to intralesional or topical agents that act on a cellular level. There is no universally accepted treatment regimen and no evidence-based literature to guide management. Our objectives are to present a list of available treatment regimens, their proposed mechanisms of action, and supporting evidence and to perform a meta-analysis of clinical trials to identify treatments with a better-than-even likelihood of improvement. We conducted a PubMed search through October 2005, identifying clinical studies of various treatments for hypertrophic scars and keloids. We graded the quality of each study, delineated the results into favorable vs nonfavorable, and calculated the statistical significance of the findings. The meta-analysis of 70 treatment series for various clinical measures showed a 70% chance of improvement with treatment; however, the mean amount of improvement to be expected was around 60%. There was no statistically significant difference between treatments. Most treatments for keloidal and hypertrophic scarring offer minimal likelihood of improvement. The magnitude of likely permanent improvement in any sign or symptom may be clinically meaningful but far short of cure. Novel therapies deserve further investigation but remain without proven benefit to date.

Systematic evidence-based analysis of plaque injection therapy for Peyronie's disease

OBJECTIVE

We evaluated the peer-reviewed urology literature for intraplaque injection of medication for Peyronie's disease and assessed the quality of studies via rigorous evidence-based medicine criteria.

METHODS

We performed a search of peer-reviewed literature looking at all agents used to treat Peyronie's disease by intraplaque injections. These were then evaluated using the Oxford Centre for Evidence-Based Medicine criteria, which ranks studies from strongest (level 1) to weakest (level 5) strength of evidence.

RESULTS

Of the 19 studies found involving injection therapy for Peyronie's disease, 17 showed positive results. Six studies using injectable corticosteroids were identified and though all showed positive results, they were of level 4 quality. Two collagenase injection studies (one level 4 and one level 2 study) were identified, both of which showed positive results. All four verapamil injection studies found (three level 4 and one level 2 study) showed positive results. Seven papers involving interferon alpha2-beta injections were evaluated (six level 4 and one level 1 study), five of which showed positive outcomes and two of which showed no significant benefit.

CONCLUSIONS

Ninety percent of the studies regarding Peyronie's disease showed positive outcomes. Unfortunately, most of these have not offered convincing evidence-based data, with only one positive study meeting level 1 Oxford criteria for clinical efficacy. Standardised outcome measures were not used, making comparisons difficult. These results reveal the need for the development of validated outcome measures and well-designed controlled trials to determine optimal therapeutic intervention for this disorder.

Keloids and scars: a review of keloids and scars, their pathogenesis, risk factors, and management

PURPOSE OF REVIEW

The precise mechanisms of normal and abnormal scar formation have long remained a mystery despite the extensive literature regarding wound healing. Only recently have researchers begun to delineate the complex biochemical signaling pathways that regulate these processes. This article reviews basic wound healing, while focusing on medicine's latest understanding of the development and treatment of keloids and hypertrophic scars.

RECENT FINDINGS

The importance of the transforming growth factor-beta signaling pathways and the related downstream effector molecules has proven to offer a new detailed view of scar biology. Regulation of scar metabolism with regards to collagen and wound matrix degradation is likewise showing promise in generating alternate therapies to treat abnormal scars.

SUMMARY

Understanding the exact process of normal and abnormal scar formation will help define better ways to successfully manage and potentially prevent abnormal healing like hypertrophic scars and keloids.

Development of a porcine incisional wound model and novel scarring scales

A major goal of wound management is to reduce scarring. Prior to evaluating novel anti-scarring therapies, we developed a porcine incisional wound model and scarring outcome measures. Forty-eight full-thickness incisions (3 cm in length) and excisional wounds (3 x 0.5 cm) were created on two animals and closed with sutures (n=24) or tissue adhesive (n=24). Scars were evaluated using two validated clinical scar scales and a novel scale developed for animals. Full-thickness biopsies were obtained at 5 and 8 weeks for determination of scar morphology using H&E and Congo red staining with and without polarized light. Scar tissue was classified based on the collagen fiber morphology and "redness" ratio, which is a measure of the relative distribution of collagen fiber in all three spatial dimensions. The clinical cosmetic scales were highly reliable, yet nondiscriminatory. The novel gross cosmetic and histomorphological scores were both highly reliable (0.75 and 0.70, respectively), yet poorly correlated with each other (0.17). The "redness" ratio and cross-sectional surface area measurements were also highly reliable (r=0.96 and 0.99, respectively) but unrelated to cosmetic outcomes. However, the "redness ratio" did correlate with the histomorphologic appearance of the scars, with poorer appearing clinical scars receiving lower ratios (ANOVA p=0.001). Significant differences in cosmetic scores were noted between excisional and incisional wounds favoring incisions (p=0.0019). We describe a novel porcine model for incisional and excisional wounds. The new clinical and histomorphologic outcomes were highly reliable yet poorly correlated. In general, incisional wounds healed with less apparent scarring than excisional wounds.

Wound Healing: An Overview

Understanding wound healing today involves much more than simply stating that there are three phases: inflammation, proliferation, and maturation. Wound healing is a complex series of reactions and interactions among cells and "mediators." Each year, new mediators are discovered and our understanding of inflammatory mediators and cellular interactions grows. This article will attempt to provide a concise overview on wound healing and wound management.

The keloid phenomenon: Progress toward a solution

For centuries, keloids have been an enigma and despite considerable research to unravel this phenomenon no universally accepted treatment protocol currently exists. Historically, the etiology of keloids has been hypothesized by multiple different theories; however, a more contemporary view postulates a multifactoral basis for this disorder involving nutritional, biochemical, immunological, and genetic factors that play a role in this abnormal wound healing. Critical to the process of preventing or managing keloids is the need to locally control fibroblasts and their activities at the wound site. In recent years, considerable evidence has accumulated demonstrating the importance of fatty acids and bioactive lipids in health and disease, especially those involving inflammatory disorders or immune dysfunction. If hypertrophic scarring and keloid formation can be argued to have significant inflammatory histories, then it is possible to postulate a role for lipids in their etiology and potentially in their treatment. This report briefly visits past views and theories on keloid formation and treatment, and offers a theoretical rationale for considering adjuvant fatty acid therapy for keloid management. Sufficient scientific evidence in support of fatty acid strategies for the prevention and treatment of keloids currently exists, which offer opportunities to bridge the gap between the laboratory and the clinic. The intent of this paper is to serve as a basic guideline for researchers, nutritionists, and clinicians interested in keloids and to propose new directions for keloid management.

Keloid Pathogenesis and Treatment

BACKGROUND

Keloid management can be difficult and frustrating, and the mechanisms underlying keloid formation are only partially understood.

METHODS

Using original and current literature in this field, this comprehensive review presents the major concepts of keloid pathogenesis and the treatment options stemming from them.

RESULTS

Mechanisms for keloid formation include alterations in growth factors, collagen turnover, tension alignment, and genetic and immunologic contributions. Treatment strategies for keloids include established (e.g., surgery, steroid, radiation) and experimental (e.g., interferon, 5-fluorouracil, retinoid) regimens.

CONCLUSION

The scientific basis and empiric evidence supporting the use of various agents is presented. Combination therapy, using surgical excision followed by intradermal steroid or other adjuvant therapy, currently appears to be the most efficacious and safe current regimen for keloid management.

Ineffective Treatment of Keloids with Interferon Alpha-2b

BACKGROUND

Keloids are exuberant, disfiguring scars that result from an abnormal healing process. Current established treatment strategies include surgical resection, triamcinolone steroid injection, pressure therapy, silicone therapy, and radiotherapy. None of these therapies, either alone or in combination, offers consistent recurrence-free rates above 70 to 80 percent. The antiproliferative, antifibrotic cytokine, interferon alpha-2b, may be useful in keloid management because of its ability to interfere with collagen synthesis and fibroblast proliferation.

METHODS

To determine the efficacy of interferon alpha-2b in keloid management, the authors prospectively evaluated the effects of interferon alpha-2b as postexcisional adjuvant therapy for keloids. Thirty-nine keloids in 34 patients were photographed, measured, and surgically excised. The wound bed was injected twice with either interferon alpha-2b (treatment group; n = 13 keloids) or triamcinolone (control group; n = 26 keloids) at surgery and 1 week later. The patients were followed up in the plastic surgery clinic.

RESULTS

The trial protocol was terminated at midtrial surveillance. Among the 13 keloids that were treated with postoperative intralesional interferon alpha-2b, seven recurred (54 percent recurrence rate). In contrast, in the 26 keloids that received triamcinolone (control group), only four recurred (15 percent recurrence rate). Recurrence in either group did not correlate with location of the keloid or race.

CONCLUSION

Interferon does not appear to be effective in the clinical management of keloids.

Antifibrogenic effects of liposome-encapsulated IFN-alpha2b cream on skin wounds in a fibrotic rabbit ear model

This study was conducted to assess the ability of a dermal cream containing liposome-encapsulated interferon- alpha2b (IFN-alpha2b) (LIPO+IFN) to improve hypertrophic scarring in open and reepithelialized dermal wounds in a rabbit fibrotic ear model. Full-thickness skin wounds were made in New Zealand white rabbits, and were either left untreated, treated on day 16 postsurgery (open wound), or treated on day 23 postsurgery (reepithelialized wound) with either LIPO+IFN or liposome alone (LIPO). The conditions of the wounds were monitored until day 35 postsurgery, when hypertrophic scar formation reached its peak. Dry wound weight, scar thickness, hypertrophic index (HI), and tissue cellularity of treated and untreated wounded tissue samples were evaluated as an index for scar formation. The results of this study showed that reepithelialized wounds treated with LIPO+IFN and to a lesser extent with LIPO alone were reduced in thickness, HI, and cellularity compared with untreated control wounds or LIPO+IFN-treated open wounds. Dry wound weight was also reduced but not significantly. The findings of this study suggest that LIPO+IFN is more effective than using LIPO alone in reducing the scar formation in a rabbit fibrotic ear model. Further investigation is required to confirm these results.

Keloids - clinical diagnosis, pathogenesis, and treatment options. Keloide - klinische Diagnose, Pathogenese und Behandlungsoptionen

Keloids are defined as excessive scar tissue formation extending beyond the area of the original skin injury and occurring in predisposed individuals. They are considered to be a result of abnormal wound healing. The pathogenetic mechanisms that cause keloids remain unknown. Experiments with cells derived from keloid tissue revealed a number of abnormalities in cellular functions, such as in proliferation, apoptosis, or expression of growth factors and extracellular matrix proteins. Furthermore, several studies have reported altered keratinocyte-fibroblast interactions in keloids. Despite the diverse pathological changes in cellular functions and expression profiles of cells derived from keloid tissue, recent genetic studies have provided evidence that single genes may act as major regulators of keloid formation. We provide an overview of the pathogenetic mechanisms of keloid formation in the context of their clinical characteristics and current therapeutic approaches.