Network Meta-Analysis of Different Clinical Commonly Used Drugs for the Treatment of Hypertrophic Scar and Keloid

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.

Laser Therapy in Hypertrophic and Keloid Scars: A Systematic Review and Network Meta-analysis

BACKGROUND

Laser therapy has emerged as a promising treatment modality for improving the appearance and symptoms associated with hypertrophic and keloid scars. In this network meta-analysis, we aimed to evaluate the efficacy of different laser types in treating hypertrophic and keloid scars.

METHODS

A comprehensive search of four databases was conducted to identify relevant studies published up until July 2023. Data were extracted from eligible studies and pooled as mean difference (MD) for continuous outcomes and risk ratio (RR) for dichotomous data in a network meta-analysis (NMA) model, using R software.

RESULTS

A total of 18 studies, comprising 550 patients, were included in the analysis. Pooling our data showed that fractional carbon dioxide (FCO2) plus 5-fluorouracil (5-FU) was superior to control in terms of Vancouver Scar Scale (VSS), pliability score, and thickness; [MD = - 5.97; 95% CI (- 7.30; - 4.65)], [MD = - 2.68; 95% CI (- 4.03; - 1.33)], [MD = - 2.22; 95% CI (- 3.13; - 1.31)], respectively. However, insignificant difference was observed among FCO2 plus 5-FU compared to control group in terms of erythema, vascularity, redness and perfusion, and pigmentation [MD = - 0.71; 95% CI (- 2.72; 1.30)], [MD = - 0.44; 95% CI (- 1.26; 0.38)], respectively.

CONCLUSION

Our NMA found that the FCO2 plus 5-FU was the most effective intervention in decreasing the VSS and thickness, while FCO2 plus CO2 was the most effective intervention in decreasing the pliability score. Further research is needed to determine the optimal laser parameters and long-term efficacy of laser therapy in hypertrophic and keloid scars.

LEVEL OF EVIDENCE IV

This journal requires that authors assign a level of evidence to each article. For a full description of these evidence-based medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

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.

The Pathophysiology and Management of Pathologic Scarring-a Contemporary Review

Significance: Pathologic scarring occurs secondary to imbalances in the cellular mechanisms of wound healing and affects millions of people annually. This review article aims to provide a concise overview of the pathophysiology and management of pathologic scarring for clinicians and scientists alike. Recent Advances: Contemporary research in the field has identified aberrations in transforming growth factor-β/small mothers against decapentaplegic (TGF-β/SMAD) signaling pathways as key drivers of pathologic scar formation; indeed, this pathway is targeted by many treatment modalities and translational investigations currently underway. Although intralesional injection of corticosteroids has been the gold standard in the treatment of pathologic scarring, studies show greater treatment efficacy with the use of combination injections such as triamcinolone/5-fluorouracil and triamcinolone/botulinum toxin. Adjunctive therapies including ablative fractional carbon dioxide/erbium-doped yttrium aluminum garnet and non-ablative pulsed-dye lasers, microneedling, and carboxytherapy have shown encouraging results in small cohort studies. Translational investigations involving the use of nanogels, RNA interference, and small molecules targeting TGF-β/SMAD pathways are also currently underway and hold promise for the future. Critical Issues: The heterogeneous nature of hypertrophic scars and keloids poses significant challenges in formulating standardized treatment and assessment protocols, thereby limiting the conclusions that can be drawn. Future Directions: Rigorous clinical trials into the individual and synergistic effects of these therapies would be ideal before any definitive conclusions or evidence-based treatment recommendations can be made. Owing to the heterogeneity of the pathology and patient population, well-conducted cohort studies may be the next best option.

Recurrence rates in the treatment of keloids and hypertrophic scars with intralesional triamcinolone combined with other intralesional agents

Hypertrophic scars (HTS) and keloids are pathologic scars that are products of a wound healing pathway error attributed to genetic and inflammatory causes (Leventhal et al., Arch Facial Plast Surg 8(6):362-368. https://doi.org/10.1001/archfaci.8.6.362 , 2006). Methods of pathologic scar treatment include intralesional agents, cryotherapy, surgical excision, pressure dressings, topical agents, laser resurfacing, radiotherapy, and other investigational therapies (Leventhal et al. 2006). The recurrence of pathologic scar is high across all treatment modalities, including the use of intralesional agents (Trisliana Perdanasari et al., Arch Plast Surg 41(6):620-629. https://doi.org/10.5999/aps.2014.41.6.620 , 2014). In the treatment of pathologic scar, combination approaches using intralesional agents, such as triamcinolone (TAC), 5-fluorouracil (5FU), verapamil (VER), bleomycin (BLM), and botulinum toxin (BTX), are superior therapies when compared to monotherapy (Yosipovitch et al., J Dermatol Treat 12(2):87-90. https://doi.org/10.1080/095466301317085363 , 2001; Yang et al., Front Med 8:691628. https://doi.org/10.3389/fmed.2021.691628 , 2021; Sun et al., Aesthetic Plast Surg 45(2):791-805. https://doi.org/10.1007/s00266-019-01570-8 , 2021). This review assesses recurrence and the reporting of recurrence in pathologic scar after treatment with intralesional triamcinolone (TAC) in combination with another intralesional agent. A literature review was conducted using research journals from PubMed using the following search terms: [(keloid) AND (triamcinolone) AND (combination) AND (intralesional)], as well as [(keloid) AND (triamcinolone) AND (combination)]. Articles were reviewed and included if the article analyzed  or compared intralesional agents for pathologic scar treatment within the last 10 years. The average follow-up period of included articles (n = 14) that utilized combination intralesional therapy (TAC-X) was approximately 11 months (range 1-24 months). Consistent recurrence rate reporting across studies was lacking. The combination agent with the highest recurrence rate was TAC-5FU (23.3%). The range of reported recurrence rates was 7.5-23.3%. Six studies using various intralesional combination regimens reported 0% recurrence over the follow-up period (TAC-5FU, TAC-BTX, TAC-BLM, TAC-CRY). Three studies did not report recurrence rates. While the efficacy of combination therapy is typically assessed via scar scales, the assessment of recurrence across studies of combination therapy is inconsistent and inadequate, with truncated follow-up periods. While scar recurrence can take place during 1-year post-treatment, long-term follow-up (18-24 months) is needed to characterize recurrence in the treatment of pathologic scar using various intralesional agents. Long-term follow-up periods allow patients to receive accurate prognostic information regarding recurrence after combination intralesional therapy. There are limitations to this review in that comparisons were made across studies with varying outcome variables, including scar size, injection concentration and interval, and follow-up period. Standardized follow-up periods and recurrence rate reporting are integral to furthering the understanding of these therapies and enhancing patient care.

Progress in the clinical treatment of keloids

Keloid is a pathological scar that is higher than the skin surface following skin damage. Its lesion range often extends beyond the original damage boundary and does not naturally subside over time. Its pathogenesis is very complex, currently the main causes include fibroblast excessive proliferation, collagen and extracellular matrix (Extracellular matrix, ECM) excessive deposition, excessive angiogenesis, and so on. The traditional treatment method primarily involves surgical intervention, but it is associated with a high recurrence rate post-surgery. Consequently, many treatment methods are derived according to the different clinical characteristics of keloid. This paper will review the therapeutic progress in recent years from surgical treatment, physiotherapy, drug therapy, and biological therapy, with the goal of offering valuable insights for the clinical treatment of keloids.

Development and validation of a risk assessment scale for pathological scarring

To develop a risk assessment scale for pathological scarring and validate its psychometric properties. This was a methodological study. Researchers developed the scale based on a literature review, qualitative study and Delphi expert consultation. Subsequently, 409 patients participated in the study to test the psychometric properties of the scale. We evaluated construct validity, content validity, internal consistency reliability, and interrater reliability. The researchers developed a scale consisting of three dimensions and 12 items. Factor analysis extracted a total of four common factors that accounted for 62.22% of the total variance. The results revealed that the item-content validity index (I-CVI) ranged from 0.67 to 1, while the scale-content validity index (S-CVI) was 0.82. Internal consistency reliability: Cronbach's α of the items ranged from 0.67 to 0.76, while Cronbach's α of the whole scale was 0.74. Interrater reliability: the Kappa number was 0.73. The final scale showed adequate construct validity, content validity, and reliability. It is appropriate for use in research and clinical practice settings to identify patients with a risk of pathological scarring. Further study is needed to confirm the scale's validity and reliability in other settings and populations.

Current Practice in Keloid Treatment: a Survey of Dutch Dermatologists and Plastic Surgeons

BACKGROUND

Several therapeutic options are available for the treatment of keloids, but it remains unclear which treatment options are most commonly used by practitioners.

OBJECTIVE

To explore the prevailing treatment for different keloid phenotypes among dermatologists and plastic surgeons in the Netherlands.

METHODS

Members of the Dutch society for Plastic surgery and the Dutch society for Dermatology and Venereology were asked to participate. Questions elaborated on the treatment for a small and a large keloid on the mandibula and multiple keloids on the chest.

RESULTS

One hundred forty-three responses were obtained. Heterogeneity in treatment was extremely high for the small, large, and multiple keloids with 27, 35, and 33 various first choices, respectively. Intralesional corticosteroids were most often chosen for all 3 different keloid phenotypes. These were mostly (61%) administered as monotherapy for the small keloid and mostly combined with other treatments for the large keloid (19%) and multiple keloids (43%). Surgery was chosen regularly (22%) for the large keloid, mostly combined with intralesional corticosteroids (10%) or brachytherapy (8.4%).

CONCLUSION

Keloid treatment is very heterogeneous among dermatologists and plastic surgeons, even in a relatively small country as the Netherlands. Moreover, the treatment choice depends on the keloid phenotype.

Scar Management and Dyschromia: A Summary Report from the 2021 American Burn Association State of the Science Meeting

Burn scars, and in particular, hypertrophic scars, are a challenging yet common outcome for survivors of burn injuries. In 2021, the American Burn Association brought together experts in burn care and research to discuss critical topics related to burns, including burn scars, at its State of the Science conference. Clinicians and researchers with burn scar expertise, as well as burn patients, industry representatives, and other interested stakeholders met to discuss issues related to burn scars and discuss priorities for future burn scar research. The various preventative strategies and treatment modalities currently utilized for burn scars were discussed, including relatively noninvasive therapies such as massage, compression, and silicone sheeting, as well as medical interventions such as corticosteroid injection and laser therapies. A common theme that emerged is that the efficacy of current therapies for specific patient populations is not clear, and further research is needed to improve upon these treatments and develop more effective strategies to suppress scar formation. This will necessitate quantitative analyses of outcomes and would benefit from creation of scar biobanks and shared data resources. In addition, outcomes of importance to patients, such as scar dyschromia, must be given greater attention by clinicians and researchers to improve overall quality of life in burn survivors. Herein we summarize the main topics of discussion from this meeting and offer recommendations for areas where further research and development are needed.

The Efficacy of Combination Therapy Involving Excision Followed by Intralesional 5-Fluorouracil and Betamethasone, and Radiotherapy in the Treatment of Keloids: A Randomized Controlled Trial

Background

Combined therapy for keloids is currently recommended. Surgery is one of the main options, but the measures to prevent recurrence after excision are still being explored.

Objective

The randomized controlled study aimed at evaluating the efficacy of excision followed by intralesional low concentrations of 5-fluorouracil (5-FU)(12.5 mg/mL) and betamethasone.

Methods

Sixty patients were randomly assigned to three groups. Patients in group A had excision followed by 5-FU and betamethasone intralesional injections, group B had 5-FU and betamethasone intralesional injections, and group C had excision followed by radiotherapy. Efficacy parameters were assessed from 8 to 12 months, including improvement on the Vancouver Scar Scale (VSS) and the Patient and Observer Scar Scale (POSAS), as well as side effects and recurrence. Trial registration number: ChiCTR2100046025.

Results

After 4 months' treatment, the improvement of the VSS and POSAS scores in group A was not different from that in group C (P > 0.05) but was superior to that in group B (P < 0.05); the pain and pruritus of the three groups were relieved more than 50%. After 8 to 12 months' follow-up, there was no statistical difference in the incidence of side effects and recurrence among the groups (P > 0.05).

Conclusion

Excision followed by intralesional low concentrations of 5-FU (12.5mg/mL) with betamethasone is a safe and sustainable treatment for keloid, with no significant difference from excision followed by radiotherapy.

Proceedings of the 2021 American Burn Association State and Future of Burn Science Meeting

Periodically, the American Burn Association (ABA) has convened a State of the Science meeting on various topics representing multiple disciplines within burn care and research. In 2021 at the request of the ABA President, meeting development was guided by the ABA's Burn Science Advisory Panel (BSAP) and a subgroup of meeting chairs. The goal of the meeting was to produce both an evaluation of the current literature and ongoing studies, and to produce a research agenda and/or define subject matter-relevant next steps to advance the field(s). Members of the BSAP defined the topics to be addressed and subsequently solicited for nominations of expert speakers and topic leaders from the ABA's Research Committee. Current background literature for each topic was compiled by the meeting chairs and the library then enhanced by the invited topic and breakout discussion leaders. The meeting was held in New Orleans, LA on November 2nd and 3rd and was formatted to allow for 12 different topics, each with two subtopics, to be addressed. Topic leaders provided a brief overview of each topic to approximately 100 attendees, followed by expert-lead breakout sessions for each topic that allowed for focused discussion among subject matter experts and interested participants. The breakout and topic group leaders worked with the participants to determine research needs and associated next steps including white papers, reviews and in some cases collaborative grant proposals. Here, summaries from each topic area will be presented to highlight the main foci of discussion and associated conclusions.

Biomechanical Regulatory Factors and Therapeutic Targets in Keloid Fibrosis

Keloids are fibroproliferative skin disorder caused by abnormal healing of injured or irritated skin and are characterized by excessive extracellular matrix (ECM) synthesis and deposition, which results in excessive collagen disorders and calcinosis, increasing the remodeling and stiffness of keloid matrix. The pathogenesis of keloid is very complex, and may include changes in cell function, genetics, inflammation, and other factors. In this review, we aim to discuss the role of biomechanical factors in keloid formation. Mechanical stimulation can lead to excessive proliferation of wound fibroblasts, deposition of ECM, secretion of more pro-fibrosis factors, and continuous increase of keloid matrix stiffness. Matrix mechanics resulting from increased matrix stiffness further activates the fibrotic phenotype of keloid fibroblasts, thus forming a loop that continuously invades the surrounding normal tissue. In this process, mechanical force is one of the initial factors of keloid formation, and matrix mechanics leads to further keloid development. Next, we summarized the mechanotransduction pathways involved in the formation of keloids, such as TGF-β/Smad signaling pathway, integrin signaling pathway, YAP/TAZ signaling pathway, and calcium ion pathway. Finally, some potential biomechanics-based therapeutic concepts and strategies are described in detail. Taken together, these findings underscore the importance of biomechanical factors in the formation and progression of keloids and highlight their regulatory value. These findings may help facilitate the development of pharmacological interventions that can ultimately prevent and reduce keloid formation and progression.