Evidence of invasive and noninvasive treatment modalities for hypertrophic scars: A systematic review

Efficacy and Safety of Pressure Therapy Alone and in Combination with Silicone in Prevention of Hypertrophic Scars: A Systematic Review with Meta-analysis of Randomized Controlled Trials

BACKGROUND

At present, there are many kinds of hypertrophic scar treatment methods, among which pressure therapy and silicone therapy are very common and standard therapies, but whether they are used alone or in combination is still controversial. Therefore, the purpose of this systematic review was to compare the efficacy and safety of the combination of pressure therapy and silicone therapy (PTS) with pressure therapy alone (PT) in the treatment of hypertrophic scars to provide clinicians with information so that they can make better decisions.

METHODS

Relevant randomized controlled trials (RCTs) were collected by searching PubMed, Ovid MEDLINE, Embase, ScienceDirect, Web of Science, The Cochrane Library, Scopus, and Google Scholar databases to assess scar scores (The Vancouver Scar Scale, VSS; Visual Analog Scale, VAS) and adverse effects.

RESULTS

We screened 1270 articles and included 6 RCTs including 228 patients. We found that height (MD = 0.15, 95%CI 0.10-0.21, p < 0.01) and pliability (MD = 0.35, 95%CI 0.25-0.46, p <0.01) had a significant difference, these two measures showed that the PTS group was superior to the PT group. Results in other aspects, such as VSS, vascularity, pigmentation, VAS, and adverse effects were similar between the two groups.

CONCLUSIONS

There was no significant difference between PTS and PT in the overall treatment efficacy of hypertrophic scars with similar VSS and adverse effects, but PTS might have potential benefits for height and pliability. Additional studies with larger sample size and sound methodological quality are needed to confirm our conclusions. 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 .

Extracellular vesicles from Lactobacillus druckerii inhibit hypertrophic scar fibrosis

BACKGROUND

Hypertrophic scars (HS) affect millions of people each year and require better treatment strategies. Bacterial extracellular vesicles (EVs) are advantaged by low cost and high yield which was commonly used in the treatment of diseases. Here, we investigated the therapeutic efficacy of EVs obtained from Lactobacillus druckerii in hypertrophic scar. In vitro, the effects of Lactobacillus druckerii-derived EVs (LDEVs) on Collagen I/III and α-SMA in fibroblasts obtained from HS. In vivo, a scleroderma mouse model was used to investigate the effects of LDEVs on fibrosis. The impact of LDEVs on excisional wound healing was explored. The different proteins between PBS and LDEVs treated fibroblasts derived from hypertrophic scar were studied by untargeted proteomic analysis.

RESULTS

In vitro, LDEVs treatment significantly inhibited the expression of Collagen I/III and α-SMA and cell proliferation of fibroblasts derived from HS. In vivo, LDEVs withdrawn the hypertrophic scar formation in scleroderma mouse model and decreased the expression of α-SMA. LDEVs promoted the proliferation of skin cells, new blood vessel formation and wound healing in excisional wound healing mice model. Moreover, proteomics has shown that LDEVs inhibit hypertrophic scar fibrosis through multiple pathways.

CONCLUSIONS

Our results indicated that Lactobacillus druckerii-derived EVs has the potential application in the treatment of hypertrophic scars and any other fibrosis diseases.

The Secretome of Irradiated Peripheral Mononuclear Cells Attenuates Hypertrophic Skin Scarring

Hypertrophic scars can cause pain, movement restrictions, and reduction in the quality of life. Despite numerous options to treat hypertrophic scarring, efficient therapies are still scarce, and cellular mechanisms are not well understood. Factors secreted by peripheral blood mononuclear cells (PBMCsec) have been previously described for their beneficial effects on tissue regeneration. In this study, we investigated the effects of PBMCsec on skin scarring in mouse models and human scar explant cultures at single-cell resolution (scRNAseq). Mouse wounds and scars, and human mature scars were treated with PBMCsec intradermally and topically. The topical and intradermal application of PBMCsec regulated the expression of various genes involved in pro-fibrotic processes and tissue remodeling. We identified elastin as a common linchpin of anti-fibrotic action in both mouse and human scars. In vitro, we found that PBMCsec prevents TGFβ-mediated myofibroblast differentiation and attenuates abundant elastin expression with non-canonical signaling inhibition. Furthermore, the TGFβ-induced breakdown of elastic fibers was strongly inhibited by the addition of PBMCsec. In conclusion, we conducted an extensive study with multiple experimental approaches and ample scRNAseq data demonstrating the anti-fibrotic effect of PBMCsec on cutaneous scars in mouse and human experimental settings. These findings point at PBMCsec as a novel therapeutic option to treat skin scarring.

Hypertrophic Scars and Keloids: Advances in Treatment and Review of Established Therapies

Hypertrophic scars and keloids can have significant detrimental effects on patients both psychosocially and functionally. A careful identification of patient risk factors and a comprehensive management plan are necessary to optimize outcomes. Patients with a history of dystrophic scarring should avoid unnecessary procedures and enhance the wound-healing process using various preventive strategies. As there is no single, fully efficacious treatment modality, prevention remains the best approach in reducing aberrant scar formation. When prevention therapies fail, keloids have been shown to be respond to a variety of therapies including topical and injectable corticosteroids, 5-fluorouracil, radiotherapy, lasers, and surgical excision, all with varying efficacies. As such, management should be tailored to the individual patient's risk factors with the use of combination therapies to reduce recurrence rates. Still, keloid and hypertrophic scar therapies are widely diverse with novel treatment modalities providing alternatives for recurring lesions. Laser-assisted drug delivery, skin priming, and novel topical therapies may provide alternative options for the management of hypertrophic scars and keloids.

Management of hypertrophic scars in adults: A systematic review and meta-analysis

Hypertrophic scars (HTS) are elevated scars which occur due to abnormalities in wound healing after injury and may be associated with pain, pruritus and functional impairment. Despite multiple available treatment options, there is no universal approach to treating HTS. We searched the Web of Science (Core Collection), MEDLINE and EMBASE databases. Title, abstract and full-text screening, along with data extraction, were performed in duplicate. Risk of bias was assessed using the Cochrane risk-of-bias tool. The Vancouver Scar Scale (VSS) scores and mean differences were used for meta-analysis. We screened 3800 abstracts and included 34 randomised controlled trials evaluating treatments for HTS in adults. Silicone and laser modalities improved VSS scores by 5.06 (95% CI: 6.78, 3.34) and 3.56 (95% CI: 5.58, 1.54), respectively. Intralesional triamcinolone combined with silicone or 5-fluorouracil was superior to intralesional triamcinolone monotherapy. Limitations of this study include exclusion of studies which did not utilise VSS, and pooling of studies based on common modalities. Further studies are needed to examine the efficacy of existing and emerging treatment modalities for HTS. Our study supports the treatment of HTS in adults with silicone gel or sheets, injected triamcinolone (preferably combined with 5-fluorouracil or silicone products), pulsed dye laser and fractionated CO₂ laser.

The Most Current Algorithms for the Treatment and Prevention of Hypertrophic Scars and Keloids: A 2020 Update of the Algorithms Published 10 Years Ago

BACKGROUND

In 2010, this Journal published my comprehensive review of the literature on hypertrophic scars and keloids. In that article, I presented evidence-based algorithms for the prevention and treatment of these refractory pathologic scars. In the ensuing decade, substantial progress has been made in the field, including many new randomized controlled trials. To reflect this, I have updated my review.

METHODS

All studies were evaluated for methodologic quality. Baseline characteristics of patients were extracted along with the interventions and their outcomes. Systematic reviews, meta-analyses, and comprehensive reviews were included if available.

RESULTS

Risk factors that promote hypertrophic scar and keloid growth include local factors (tension on the wound/scar), systemic factors (e.g., hypertension), genetic factors (e.g., single-nucleotide polymorphisms), and lifestyle factors. Treatment of hypertrophic scars depends on scar contracture severity: if severe, surgery is the first choice. If not, conservative therapies are indicated. Keloid treatment depends on whether they are small and single or large and multiple. Small and single keloids can be treated radically by surgery with adjuvant therapy (e.g., radiotherapy) or multimodal conservative therapy. For large and multiple keloids, volume- and number-reducing surgery is a choice. Regardless of the treatment(s), patients should be followed up over the long term. Conservative therapies, including gel sheets, tape fixation, topical and injected external agents, oral agents, and makeup therapy, should be administered on a case-by-case basis.

CONCLUSIONS

Randomized controlled trials on pathologic scar management have increased markedly over the past decade. Although these studies suffer from various limitations, they have greatly improved hypertrophic scar and keloid management. Future high-quality trials are likely to improve the current hypertrophic scar and keloid treatment algorithms further.

The serine proteases dipeptidyl-peptidase 4 and urokinase are key molecules in human and mouse scar formation

Despite recent advances in understanding skin scarring, mechanisms triggering hypertrophic scar formation are still poorly understood. In the present study, we investigate mature human hypertrophic scars and developing scars in mice at single cell resolution. Compared to normal skin, we find significant differences in gene expression in most cell types present in scar tissue. Fibroblasts show the most prominent alterations in gene expression, displaying a distinct fibrotic signature. By comparing genes upregulated in murine fibroblasts during scar development with genes highly expressed in mature human hypertrophic scars, we identify a group of serine proteases, tentatively involved in scar formation. Two of them, dipeptidyl-peptidase 4 (DPP4) and urokinase (PLAU), are further analyzed in functional assays, revealing a role in TGFβ1-mediated myofibroblast differentiation and over-production of components of the extracellular matrix in vitro. Topical treatment with inhibitors of DPP4 and PLAU during scar formation in vivo shows anti-fibrotic activity and improvement of scar quality, most prominently after application of the PLAU inhibitor BC-11. In this study, we delineate the genetic landscape of hypertrophic scars and present insights into mechanisms involved in hypertrophic scar formation. Our data suggest the use of serine protease inhibitors for the treatment of skin fibrosis.

Factors Influencing Hypertrophic Scarring after Thyroidectomy

OBJECTIVE

To identify the risk factors of hypertrophic scarring (HS) after thyroidectomy and construct a risk prediction model.

METHODS

From November 2018 to March 2019, the clinical data of patients undergoing thyroidectomy were collected for retrospective analysis. According to the occurrence of HS, the patients were divided into an HS group and a non-HS group. Univariate analysis and binary logistic regression analysis were conducted to explore the independent risk factors for HS. Receiver operating characteristic analysis was also carried out.

RESULTS

In this sample, 121 of 385 patients developed HS, an incidence of 31.4%. Univariate analysis showed significant differences in sex, age, postoperative infection, history of abnormal wound healing, history of pathologic scar, family history of pathologic scar, and scar prevention measures between the two groups (P < .05). Binary logistic regression analysis indicated that age 45 years or younger (odds ratio [OR], 1.815), history of abnormal wound healing (OR, 4.247), history of pathologic scarring (OR, 9.840), family history of pathologic scarring (OR, 5.708), and absence of preventive scar measures (OR, 5.566) were independent factors for HS after thyroidectomy. The area under the receiver operating characteristic curve was 0.837. When the optimal diagnostic cutoff value was 0.206, the sensitivity was 0.661, and the specificity was 0.932.

CONCLUSIONS

The development of HS after thyroidectomy is related to many factors, and the proposed risk prediction model based on the combined risk factors shows a good predictive value for postoperative HS. When researchers consider the prevention and treatment of scarring in patients at risk, the incidence of HS in different populations can provide theoretical support for clinical decision-making.

Activating transcription factor 3 (ATF3) regulates cell growth, apoptosis, invasion and collagen synthesis in keloid fibroblast through transforming growth factor beta (TGF-beta)/SMAD signaling pathway

The successful treatment of keloids is a great challenge in the plastic surgery field. Activating transcription factor 3 (ATF3) is discovered as an adaptive responsive gene, which plays a critical role in fibroblast activation. This study aimed to investigate the expression and biological role of ATF3 in the pathogenesis of keloids. ATF3 expression in normal skins and keloids was evaluated by real-time PCR, western blot and immunohistochemistry. Effects of ATF3 on cell growth, apoptosis, invasion and collagen production were evaluated in keloid fibroblast cells overexpressing or downregulating ATF3. ATF3 expression was significantly elevated in keloid tissues when compared with that of normal skins and parakeloidal skin tissues. Moreover, ATF3 promoted cell proliferation and collagen production in keloid fibroblast cells. Conversely, transfection with siRNA targeting ATF3 led to decreased cell viability and collagen synthesis via inhibiting transforming growth factor-β1 (TGF-β1) and fibroblast growth factor 2/8 (FGF2/8) production in keloid fibroblasts. ATF3 could reduce the apoptosis rate of keloid fibroblast cells. Molecularly, we found that ATF3 promoted BCL2 level and inhibit the expression of BCL2 associated agonist of cell death (Bad), Caspase3 and Caspase9 in keloid fibroblast cells. ATF3 also enhanced the invasive potential via upregulating the expression of Matrix Metalloproteinases (MMP) family members (MMP1, MMP2, MMP9 and MMP13). ATF3 could induce activation of TGF-β/Smad signaling pathway in fibroblasts. Collectively, ATF3 could promote growth and invasion, and inhibit apoptosis via TGF-β/Smad pathway in keloid fibroblast cells, suggesting that ATF3 might be considered as a novel therapeutic target for the management of keloid.

Statin treatment and hypertrophic scarring after cardiac surgery

Wound healing process after surgical procedure plays a crucial role to prevent blood loss and infections. Hypertrophic scars might occur after surgery and are generally associated with an inflammatory burden. Cardiac surgery is intrinsically related to a strong systemic inflammatory state that might favor hypertrophic scarring. Besides lipid-lowering effects, statins are known for their pleiotropic and anti-inflammatory activity. The aim of this study was to investigate the impact of statins in the healing process after median sternotomy in patients undergoing cardiac surgery. All patients undergoing major cardiac surgery with median sternotomy and cardiopulmonary bypass, and subsequently evaluated in the outpatient clinic after discharge, were included in this study. A total of 930 Caucasian patients were retrospectively reviewed. At outpatient visit, 276 patients (29.7%) showed the formation of hypertrophic scars. Patients with hypertrophic scars tended to be younger (P = .001) and nonstatin users (P = .001). Logistic regression analysis confirmed the protective role of statins (odds ratio 0.39, 95% confidence interval 0.29-0.53, P = .001), after adjustment for age. A dose-dependent effect was confirmed, showing a more intensive protective effect for higher doses of statins. Statin use might be correlated with reduced hypertrophic scars after cardiac surgery through median sternotomy. A dose-dependent effect has been shown, and statin effect seems to be independent of age in a selected population undergoing surgery with an elevated inflammatory burden. Although further studies are warranted to elucidate the biologic mechanisms, the concept of using statins as anti-scarring agents is novel and should be investigated with tailored studies.

[Multicenter study of the effectiveness of antiscar therapy in patients at different age periods]

OBJECTIVE

Was to evaluate the effectiveness of anti-scar treatment with Contractubex gel in children and adults.

MATERIAL AND METHODS

A group of researchers based on clinical hospitals and university medical clinics carry out the multicenter study to evaluate the effectiveness of anti-scar treatment with Contractubex gel containing cepalin, allantoin and heparin, with its early appointment in groups of children from 12 to 18 years old and adults from 21 to 35 years old. The study included data from 216 patients. Patients of both age groups were initially divided into two: the main and control ones with an equal distribution according to the type of surgical intervention (hernia repair and appendectomy), age, gender, and anamnestic data. The dynamic observation was carried out using two rating scales - filled out by a doctor (Vancouver scale) and a patient (author's rating scale in the Scar Diary mobile application).

RESULTS

Based on the results of the analysis of the data obtained, a high efficiency of the use of Contractubex gel at the early stages of scar formation among patients of the main group in comparison with the control was revealed. By 90 days, the treatment result according to the Vancouver scale was 0,16±0,1 points in the main group and 0,39±0,2 points in the control group. At the same time, with a dynamic scale for assessing the cicatricial process, there was a significant (p<0.05) improvement in the main group (0,2±0,06 points) compared with the control group (0,6±0,17 points). In addition, was noticed the strong commitment to anti-scar treatment in pediatric patients.

CONCLUSIONS

The work confirms the undoubted need for anti-scar treatment in the early stages of scar formation after surgical interventions, which accelerates the psychophysical rehabilitation of patients after surgery and improves the quality of life.

Ablative fractional laser treatment of hypertrophic burn and traumatic scars: a systematic review of the literature

Hypertrophic scars (HTS) following burns and other trauma and are associated with significant functional and psychosocial impairment. Ablative fractional lasers (AFLs) are increasingly being applied in the treatment of HTS supported by a rapidly expanding multidisciplinary base of literature. The multidisciplinary authors sought to evaluate existing literature, provide context and identify gaps, and make recommendations for a path forward. A systematic review was conducted to identify literature pertinent literature through September 2019. Retrospective cohort, randomized controlled trials, quasi-randomized controlled trials, observational prospective cohort, or case series with five or more subjects with hypertrophic scars incurred from burns and related trauma were considered. Twenty-two of the 23 evaluated studies documented statistically significant and/or meaningful qualitative improvements in nearly all outcome measures. Adverse events were generally infrequent and minor. Significant heterogeneity was observed among the studies included in this systematic review, precluding metaanalysis of pooled data. There is abundant existing literature on the use of AFLs in the management of HTS but study heterogeneity limits generalizability. Future studies should prioritize standardized protocols including assessments of function and quality of life.

Evidence-based therapy in hypertrophic scars: An update of a systematic review

Hypertrophic scars are still a major burden for numerous patients, especially after burns. Many treatment options are available; however, no evidence-based treatment protocol is available with recommendations mostly emerging from experience or lower quality studies. This review serves to discuss the currently available literature. A systematic review was performed and the databases PubMed and Web of Science were searched for suitable publications. Only original articles in English that dealt with the treatment of hypertrophic scars in living humans were analyzed. Further, studies with a level of evidence lower than 1 as defined by the American Society of Plastic Surgeons were excluded. After duplicate exclusion, 1638 studies were screened. A qualitative assessment yielded 163 articles eligible for evidence grading. Finally nine studies were included. Four of them used intralesional injections, four topical therapeutics and one assessed the efficacy of CO₂ -laser. Intralesional triamcinolone + fluorouracil injections, and topical pressure and/or silicone therapy revealed significant improvements in terms of scar height, pliability, and pigmentation. This systematic review showed that still few high-quality studies exist to evaluate therapeutic means and their mechanisms for hypertrophic scars. Among these, most of them assessed the efficacy of intralesional triamcinolone injections with the same treatment protocol. Intralesional injection appears to be the best option for hypertrophic scar treatment. Future studies should focus on a possible optimization of infiltrative therapies, consistent end-point evaluations, adequate follow-up periods, and possibly intraindividual treatments.

3D Mesh Releasing Method: A Retrospective Analysis of Fractional CO2 Treatment on Contracture Scars

BACKGROUND AND OBJECTIVES

There has been reports on fractional CO₂ laser successfully improving contracture scars that impair the function of a joint. It seems that certain contracture problems could be solved by laser instead of surgery. However, the clinical application could be difficult when the efficacy of the method remains unknown. The purpose of this study is to report the releasing capacity of the fractional CO₂ laser on contracture scars based on a defined treatment method.

STUDY DESIGN/MATERIALS AND METHODS

We conducted a retrospective study in patients with limited function in joints caused by contracture scars. Fractional CO₂ laser and our "3D mesh releasing" protocol were applied. The primary outcome was the improvement measured in range of motion (ROM) of the relevant joint before all intervention and 6 months after the last treatment.

RESULT

From November 2016 to January 2018, 11 joints of 10 cases were treated by the fractional CO₂ laser. Patients went through 2.27 (standard deviation [SD] 1.42, 1-5) sessions. The average progress of ROM before and 6 months after all treatments was 19.13° (SD 10.25, P < 0.02). In six cases, we recorded that there was an 8.53° (SD 5.81, P < 0.02) of increase in ROM immediately after the laser session, and the average improvement reached up to 13.58° (SD 8.15, P < 0.02) after 2-3 months during the next follow-up.

CONCLUSION

The fractional CO₂ laser could achieve functional improvement in contracture scars and it maintained its effect for at least 6 months. The "3D Mesh Releasing" protocol would help to standardize the treatment procedure. This modality has minimal-invasiveness and potentially could become a supplement to the current treatment choices for mild contracture scars. Lasers Surg. Med. © 2020 Wiley Periodicals LLC.

Management of highly recurrent bladder neck contractures via transurethral resection combined with intra- and post-operative triamcinolone acetonide injections

PURPOSE

To present our preliminary experience in managing patients with highly recurrent bladder neck contractures (BNCs) after transurethral resection of the prostate (TURP).

METHODS

Between February 2015 and March 2018, 28 patients with highly recurrent BNCs who had failed multiple prior to endoscopic treatments were managed with transurethral resection and intra- and post-operative triamcinolone acetonide injections. The scar tissue was resected to the circular fiber at the bladder neck, and triamcinolone acetonide (2 mL, 40 mg/mL) was injected at the incision sites (8 points) using a cystoscopic injection needle. The cystoscopy-guided injections were repeated every four weeks for total three times after surgery. The patients were followed up at 3, 6, 12 months after surgery, and in July-August 2019.

RESULTS

The recurrent interval before the treatments was 2.2 ± 1.2 months, without any BNC recurrence in the first 12 weeks after transurethral resection. The urinary flow rate increased significantly and was maintained during the follow-up period. Adequate voiding function was reported in 25 of 28 patients at a median follow-up of 2.8 (1.7, 3.9) years. One of the three patients with decreased urinary flow rate had underactive detrusor and no BNC recurrence. The complications were mild and tolerable.

CONCLUSION

Transurethral resection of the scar tissue combined with intra- and post-operative triamcinolone acetonide injections resulted in a success rate of 92.9% in patients with highly recurrent BNC following TURP. It is a simple, safe, and effective treatment for highly recurrent BNCs.

Use of self-adherent silicone sheets in a pediatric burn patient: A case report and instructions for use

Burns and scalds are relatively common injuries in children. Formation of hypertrophic scars or keloids is feared complications. A 2-year-old girl who spilled a cup of hot coffee onto herself developed widespread hypertrophic scars and beginning keloids on her upper chest, despite application of pressure garments and daily massage with silicone gel. Herein, we describe instructions for use of prolonged continuous 24-hour occlusive application of self-adherent silicone sheets to help mitigate the formation of scar tissue.

Diagnosis and Treatment of Keloids and Hypertrophic Scars-Japan Scar Workshop Consensus Document 2018

There has been a long-standing need for guidelines on the diagnosis and treatment of keloids and hypertrophic scars that are based on an understanding of the pathomechanisms that underlie these skin fibrotic diseases. This is particularly true for clinicians who deal with Asian and African patients because these ethnicities are highly prone to these diseases. By contrast, Caucasians are less likely to develop keloids and hypertrophic scars, and if they do, the scars tend not to be severe. This ethnic disparity also means that countries vary in terms of their differential diagnostic algorithms. The lack of clear treatment guidelines also means that primary care physicians are currently applying a hotchpotch of treatments, with uneven outcomes. To overcome these issues, the Japan Scar Workshop (JSW) has created a tool that allows clinicians to objectively diagnose and distinguish between keloids, hypertrophic scars, and mature scars. This tool is called the JSW Scar Scale (JSS) and it involves scoring the risk factors of the individual patients and the affected areas. The tool is simple and easy to use. As a result, even physicians who are not accustomed to keloids and hypertrophic scars can easily diagnose them and judge their severity. The JSW has also established a committee that, in cooperation with outside experts in various fields, has prepared a Consensus Document on keloid and hypertrophic scar treatment guidelines. These guidelines are simple and will allow even inexperienced clinicians to choose the most appropriate treatment strategy. The Consensus Document is provided in this article. It describes (1) the diagnostic algorithm for pathological scars and how to differentiate them from clinically similar benign and malignant tumors, (2) the general treatment algorithms for keloids and hypertrophic scars at different medical facilities, (3) the rationale behind each treatment for keloids and hypertrophic scars, and (4) the body site-specific treatment protocols for these scars. We believe that this Consensus Document will be helpful for physicians from all over the world who treat keloids and hypertrophic scars.

Could -79 °C Spray-Type Cryotherapy Be an Effective Monotherapy for the Treatment of Keloid?

Cryotherapy has been regarded as an effective modality for the treatment of keloids, and the spray-type device is one of the novel cryotherapeutic units. However, the biological mechanisms and therapeutic effects of this technique are incompletely studied. We evaluated the clinical efficacy of our cryotherapy protocol with molecular and pathologic evidence for the treatment of keloids. We evenly split each of ten keloid lesions into a non-treated (C-) and treated (C+) area; the C+ area was subjected to two freeze-thaw cycles of spray-type cryotherapy using -79 °C spray-type CryoPen™. This treatment was repeated after an interval of two weeks. The proliferation and migration abilities of the fibroblasts isolated from the dermis under the cryotherapy-treated or untreated keloid tissues (at least 5 mm deep) were compared and pathologic findings of the full layer were evaluated. Molecular analysis revealed that the number of dermal fibroblasts was significantly higher in C+ group as compared with C- group. The dermal fibroblasts from C+ group showed more than two-fold increase in the migration ability as compared with the fibroblasts from C- group. The expression of matrix metallopeptidase 9 was increased by more than two-fold and a significant increase in transforming growth factor beta 1 expression and Smad2/3 phosphorylation level was observed in C+ group. C+ group showed more extensive lymphoplasmacytic infiltration with thicker fibrosis and occasional "proliferating core collagen" as compared with C- group. Thus, -79 °C spray-type cryotherapy is ineffective as a monotherapy and should be used in combination with intralesional corticosteroids or botulinum toxin A for favourable outcomes in the treatment of thick keloids.