Keloids and hypertrophic scars

Non-invasive imaging of pathological scars using a portable handheld two-photon microscope

BACKGROUND

Pathological scars are a disorder that can lead to various cosmetic, psychological, and functional problems, and no effective assessment methods are currently available. Assessment and treatment of pathological scars are based on cutaneous manifestations. A two-photon microscope (TPM) with the potential for real-time non-invasive assessment may help determine the under-surface pathophysiological conditions in vivo . This study used a portable handheld TPM to image epidermal cells and dermal collagen structures in pathological scars and normal skin in vivo to evaluate the effectiveness of treatment in scar patients.

METHODS

Fifteen patients with pathological scars and three healthy controls were recruited. Imaging was performed using a portable handheld TPM. Five indexes were extracted from two dimensional (2D) and three dimensional (3D) perspectives, including collagen depth, dermo-epidermal junction (DEJ) contour ratio, thickness, orientation, and occupation (proportion of collagen fibers in the field of view) of collagen. Two depth-dependent indexes were computed through the 3D second harmonic generation image and three morphology-related indexes from the 2D images. We assessed index differences between scar and normal skin and changes before and after treatment.

RESULTS

Pathological scars and normal skin differed markedly regarding the epidermal morphological structure and the spectral characteristics of collagen fibers. Five indexes were employed to distinguish between normal skin and scar tissue. Statistically significant differences were found in average depth ( t = 9.917, P <0.001), thickness ( t = 4.037, P <0.001), occupation ( t = 2.169, P <0.050), orientation of collagen ( t = 3.669, P <0.001), and the DEJ contour ratio ( t = 5.105, P <0.001).

CONCLUSIONS

Use of portable handheld TPM can distinguish collagen from skin tissues; thus, it is more suitable for scar imaging than reflectance confocal microscopy. Thus, a TPM may be an auxiliary tool for scar treatment selection and assessing treatment efficacy.

Therapeutic and prophylactic effects of radiation therapy in the management of recurrent granulation tissue induced tracheal stenosis: a review on the role of Endobronchial brachytherapy and external beam radiation therapy

PURPOSE

Granulation tissue-induced tracheal stenosis (mainly secondary to intubation or lung transplantation) is one of the most common etiologies of benign airway obstructions. Recurrence rates after standard treatment options (surgical resection and/or endobronchial interventions) can inadvertently worsen the stricture through the stimulation of more granulation tissue generation (via increased fibroblast activity and roliferation). Low-dose radiotherapy could be a promising tool to prevent granulation tissue formation after surgery and/or endobronchial interventions regarding its established role in the treatment of keloids or hypertrophic scars, two benign diseases with similar a pathophysiology to tracheal stenosis. This study reviews case reports and small series that used endobronchial brachytherapy (EBBT) or external beam radiotherapy (EBRT) for the management of refractory granulation tissue-induced tracheal stenosis after surgery and/or endobronchial interventions.

METHODS AND MATERIALS

Case reports and series (published up to October 2022) that reported outcomes of patients with recurrent granulation tissue-induced tracheal stenosis (after surgery and/or endobronchial interventions) treated by EBBT or EBRT (in definitive or prophylactic settings) were eligible.

RESULTS

Sixteen studies (EBBT: nine studies including 69 patients, EBRT: seven studies including 32 patients) were reviewed. The pooled success rate across all studies was 74% and 97% for EBBT and EBRT, respectively.

CONCLUSIONS

Radiation therapy appears to be effective in the management of selected patients with recurrent/refractory tracheal stenosis. Response to this treatment is usually good, but further studies with a larger number of patients and long-term followup are necessary to determine the optimal technique, dose, and timing of radiation therapy, late complications, the durability of response, and criteria for patient selection.

Keloid treatments: an evidence-based systematic review of recent advances

BACKGROUND

Keloids are pathologic scars that pose a significant functional and cosmetic burden. They are challenging to treat, despite the multitude of treatment modalities currently available.

OBJECTIVE

The aim of this study was to conduct an evidence-based review of all prospective data regarding keloid treatments published between 2010 and 2020.

METHODS

A systematic literature search of PubMed (National Library of Medicine), Embase (Elsevier), and Cochrane Library (Wiley) was performed in November of 2020. Search strategies with the keywords "keloid" and "treatment" were performed by a medical librarian. The search was limited to prospective studies that were peer-reviewed, reported on clinical outcomes of keloid therapies, and were published in the English language between January 1, 2010, and November 24, 2020.

RESULTS

A total of 3462 unique citations were identified, of which 108 studies met inclusion criteria. Current literature supports silicone gel or sheeting with corticosteroid injections as first-line therapy for keloids. Adjuvant intralesional 5-fluorouracil (5-FU), bleomycin, or verapamil can be considered, although mixed results have been reported with each. Laser therapy can be used in combination with intralesional corticosteroids or topical steroids with occlusion to improve drug penetration. Excision of keloids with immediate post-excision radiation therapy is an effective option for recalcitrant lesions. Finally, silicone sheeting and pressure therapy have evidence for reducing keloid recurrence.

CONCLUSIONS

This review was limited by heterogeneity of subject characteristics and study outcome measures, small sample sizes, and inconsistent study designs. Larger and more robust controlled studies are necessary to further understand the variety of existing and emerging keloid treatments, including corticosteroids, cryotherapy, intralesional injections, lasers, photodynamic therapy, excision and radiation, pressure dressings, and others.

Keloid disease: Review with clinical atlas. Part I: Definitions, history, epidemiology, clinics and diagnosis

Keloids are chronic progressive dermal pseudo-tumors that can grow considerably in volume and surface area but do not invade other tissues. They are usually triggered by dermal injury or inflammation, but they are not scars in the normal sense of the word, since they enlarge and progress over decades. The phenomenon usually referred to as "hypertrophic scars" represents a kind of keloidal process that does not extend beyond the initial site of injury and spontaneously regresses in 12-24 months. The multiplication of keloids and hypertrophic scars in a single patient is known as keloid disease. Keloid disease is due to a familial predisposition (autosomal dominant) that preferentially affects people of non-European ancestry, especially those of sub-Saharan African descent. Keloid disease has a deep impact on quality of life, not only because of disfiguring lesions, but also because of the frequency of associated intense neurogenic pruritus and pain, as well as recurrent bouts of suppuration. Diagnosis relies primarily on a good knowledge of the clinical characteristics of keloids, thus warranting the inclusion of a clinical atlas in the first part of the review. The second part will deal with the pathology, pathophysiology and treatment of keloid disease.

Prominent Role of Type 2 Immunity in Skin Diseases-Beyond Atopic Dermatitis

Type 2 immunity, illustrated by T helper 2 lymphocytes (Th2) and downstream cytokines (IL-4, IL-13, IL-31) as well as group 2 innate lymphoid cells (ILC2), is important in host defense and wound healing.¹ The hallmark of type 2 inflammation is eosinophilia and/or high IgE counts and is best recognized in atopic diathesis. Persistent eosinophilia, such as seen in hypereosinophilic syndromes, leads to fibrosis and hence therapeutic Type 2 inhibition in fibrotic diseases is of high interest. Furthermore, as demonstrated in cutaneous T cell lymphoma, advanced disease is characterized by Th1 to Th2 switch allowing cancer progression and immunosuppression. Development of targeted monoclonal antibodies against IL-4Rα (eg, dupilumab) led to a paradigm shift for the treatment of atopic dermatitis (AD) and stimulated research to better understand the role of Type 2 inflammation in other skin conditions. In this review, we summarize up to date knowledge on the role of Type 2 inflammation in skin diseases other than AD and highlight whether the use of Type 2 targeted therapies has been documented or is being investigated in clinical trials. This manuscript reviews the role of Type 2 inflammation in dermatitis, neurodermatitis, IgE-mediated dermatoses (eg, bullous pemphigoid, chronic spontaneous urticaria), sclerodermoid conditions and skin neoplasms.

Suppurative keloids: a complication of severe keloid disease

BACKGROUND

Some keloids show cystic cavities that give rise to acute inflammatory flares and oozing. These suppurative keloids (SK) have rarely been systematically studied. We conducted a retrospective cohort study to evaluate SK frequency and its risk factors. We also reviewed microbiological analyses as well as the histological features of removed SKs.

METHODS

Between July 1, 2015, and September 30, 2016, all adult patients attending a specialized keloid clinic were asked to participate. Clinical information and microbiological results were extracted from each patient's file. Histological features were observed and interpreted.

RESULTS

In this study, we observed an SK rate of 26% for a mean keloid history of 17.2 years. Male gender, African ancestry, and a family history of keloids were significantly associated with suppuration. Microbiological examination revealed commensal skin flora 7/9 (77.8%), Staphylococcus aureus 1/9 (11.1%), and Enterococcus faecalis 1/9 (11.1%).

CONCLUSION

Suppuration is a common complication of keloids occurring in patients with severe keloid disease and may arise from pilosebaceous occlusion and aseptic inflammation.

Treatment of Pain in Keloids Using Only a Long-Pulsed 1064 nm Nd:YAG Laser

BACKGROUND AND OBJECTIVE

Keloids are benign lesions arising from overproduction of the extracellular matrix and abnormal collagen deposition by dermal fibroblasts. This altered wound healing typically occurs in response to dermal trauma. Keloid treatment poses a challenge due to the variable nature of treatment response, which can be affected by the size, appearance, and associated symptoms of erythema, pruritus, and pain. Recently, successful treatment of keloids has been reported using the Nd:YAG laser in conjunction with 5-fluorouracil and intralesional corticosteroids. We present a series of patients with symptomatic keloids, who we treated with only a 1064 nm Nd:YAG laser.

STUDY DESIGN/MATERIALS AND METHODS

Eight patients of Fitzpatrick skin types I-VI presented for treatment of keloids with associated symptoms of pain. The keloids were most commonly located on the trunk, and seven patients had intralesional steroid injections prior to presentation with persistence of symptoms. Patient treatment consisted of two passes under a long-pulsed 1064 nm Nd:YAG laser with a 10 mm spot size, a fluence of 18-19 J/cm² , and 60 ms pulse duration every 3-8 weeks. Patient-reported pain scores were collected before and after treatment.

RESULTS

Following treatment, transient erythema and mild edema were noted at the treatment site. All patients reported improvement in the symptoms of pain, with an average of a 5-point reduction using a 10-point scale (R: 2-10). Five out of eight patients had total resolution of their pain. An average of 3.25 treatments (R:1-5) were needed for patients to first notice an improvement in the pain. A Wilcoxon signed-rank test showed that treatment with a 1064 nm laser elicited a statistically significant improvement in pain in individuals with keloids (Z = 2.46, P = 0.01). No patients in our study suffered any scarring or pigment changes as a result of these treatments.

CONCLUSION

Keloids are a common condition with variable rates of treatment satisfaction. Lasers have been used in an attempt to improve clinical appearance and associated symptoms. We report a significant reduction in pain for patients treated exclusively with a 1064 nm Nd:YAG laser. Lasers Surg. Med. © 2020 Wiley Periodicals LLC.

A topical naltrexone formulation for surgical wound healing: A case report

BACKGROUND

In current guidelines, there is no specific therapeutic recommendation for promoting surgical wound healing. Proper postsurgical wound care regimen can speed up wound healing and prevent abnormal scarring.

AIMS

The purpose of this case study was to evaluate the effectiveness of a compounded topical formulation containing naltrexone in managing surgical wound in a patient after Mohs micrographic surgery (MMS).

PATIENTS/METHODS

A patient started to apply the topical naltrexone formulation two days after the MMS on his hand. Images of the wound and a Patient Scar Assessment Questionnaire (PSAQ) were used to evaluate the clinical outcomes.

RESULTS

The wound completely healed, and the hand function was fully recovered following application of the formulation for 2 weeks. No abnormal scarring was formed, and the scar was only slightly noticeable after 2 months.

CONCLUSION

This case study demonstrated the effectiveness of the topical naltrexone formulation in surgical wound management.

Low-Grade Myofibroblastic Sarcoma Arising From Keloid Scar on the Chest Wall After Thoracic Surgery

Keloids are considered as benign fibroproliferative skin tumors, and rare cases of malignancies have been reported. We present a case of low-grade myofibroblastic sarcoma arising from a recurrent painful keloid scar on the right chest wall after video-assisted thoracic surgery for pneumothorax in a 77-year-old man. Wide composite excision of the keloid, surrounding ribs, and partial diaphragm were performed. The chest wall pleural defect was reconstructed with Teflon (Chemours, Wilmington, DE), and soft tissue was reconstructed with a transverse rectus abdominis myocutaneous flap. This case highlights that refractory keloids may be considered a harbinger of malignancy.

The Keloid Disorder: Heterogeneity, Histopathology, Mechanisms and Models

Keloids constitute an abnormal fibroproliferative wound healing response in which raised scar tissue grows excessively and invasively beyond the original wound borders. This review provides a comprehensive overview of several important themes in keloid research: namely keloid histopathology, heterogeneity, pathogenesis, and model systems. Although keloidal collagen versus nodules and α-SMA-immunoreactivity have been considered pathognomonic for keloids versus hypertrophic scars, conflicting results have been reported which will be discussed together with other histopathological keloid characteristics. Importantly, histopathological keloid abnormalities are also present in the keloid epidermis. Heterogeneity between and within keloids exists which is often not considered when interpreting results and may explain discrepancies between studies. At least two distinct keloid phenotypes exist, the superficial-spreading/flat keloids and the bulging/raised keloids. Within keloids, the periphery is often seen as the actively growing margin compared to the more quiescent center, although the opposite has also been reported. Interestingly, the normal skin directly surrounding keloids also shows partial keloid characteristics. Keloids are most likely to occur after an inciting stimulus such as (minor and disproportionate) dermal injury or an inflammatory process (environmental factors) at a keloid-prone anatomical site (topological factors) in a genetically predisposed individual (patient-related factors). The specific cellular abnormalities these various patient, topological and environmental factors generate to ultimately result in keloid scar formation are discussed. Existing keloid models can largely be divided into in vivo and in vitro systems including a number of subdivisions: human/animal, explant/culture, homotypic/heterotypic culture, direct/indirect co-culture, and 3D/monolayer culture. As skin physiology, immunology and wound healing is markedly different in animals and since keloids are exclusive to humans, there is a need for relevant human in vitro models. Of these, the direct co-culture systems that generate full thickness keloid equivalents appear the most promising and will be key to further advance keloid research on its pathogenesis and thereby ultimately advance keloid treatment. Finally, the recent change in keloid nomenclature will be discussed, which has moved away from identifying keloids solely as abnormal scars with a purely cosmetic association toward understanding keloids for the fibroproliferative disorder that they are.

Advances in diagnostic methods for keloids and biomarker-targeted fluorescent probes

A keloid is a type of unusually raised scar. Unlike other raised scars, keloids form larger sizes than the wound site due to overgrowth, generally related to various biological factors. To date, only a few diagnostic and therapeutic methods for keloids have been reported. The high recurrence rates and undesirable side effects of keloids, at the end stage, encourage the invention of novel diagnostic tools, in order to cure keloids at an earlier stage. In this review, we summarize the general information about keloid diagnosis, keloid biomarkers, and recently reported fluorescent probes that can sense the key biomarkers of keloids. The focused description of fluorescent probes for keloid biomarkers and the author's perspective give useful insights in order to design the next-generation diagnostic sensing system for keloids.

Correction of a post-traumatic scar fold in the lateral canthus using modified Z-plasty

Post-traumatic scar deformations are common in many skin injury cases. These are usually aesthetic problems, but if these deformations impair mobility and the patient feels uncomfortable, we must resolve them. In a patient with a lateral post-traumatic scar fold in the lateral canthus that shortened the horizontal orbital fissure and created traction on eye opening, we performed modified classic Z-plasty, resulting in aesthetic and functional improvements without recurrence.

Pathophysiologic Mechanisms and Current Treatments for Cutaneous Sequelae of Burn Wounds

Burn injuries are a pervasive clinical problem. Extensive thermal trauma can be life-threatening or result in long-lasting complications, generating a significant impact on quality of life for patients as well as a cost burden to the healthcare system. The importance of addressing global or systemic issues such as resuscitation and management of inhalation injuries is not disputed but is beyond the scope of this review, which focuses on cutaneous pathophysiologic mechanisms for current treatments, both in the acute and long-term settings. Pathophysiological mechanisms of burn progression and wound healing are mediated by highly complex cascades of cellular and biochemical events, which become dysregulated in slow-healing wounds such as burns. Burns can result in fibroproliferative scarring, skin contractures, or chronic wounds that take weeks or months to heal. Burn injuries are highly individualized owing to wound-specific differences such as burn depth and surface area, in addition to patient-specific factors including genetics, immune competency, and age. Other extrinsic complications such as microbial infection can complicate wound healing, resulting in prolonged inflammation and delayed re-epithelialization. Although mortality is decreasing with advancements in burn care, morbidity from postburn deformities continues to be a challenge. Optimizing specialized acute care and late burn outcome intervention on a patient-by-patient basis is critical for successful management of burn wounds and the associated pathological scar outcome. Understanding the fundamentals of integument physiology and the cellular processes involved in wound healing is essential for designing effective treatment strategies for burn wound care as well as development of future therapies. Published 2018. Compr Physiol 8:371-405, 2018.

Toe keloid after nail extraction treated with surgical excision: A case report

RATIONALE

In this study, a case of toe keloid after nail extraction is presented, in which the keloids on both toes were resected by surgical excision. Keloids (from the Greek word meaning "crab's claw") are fibrous growths that extend beyond the original area of injury to involve the adjacent normal skin. In general, keloid tendencies appear to be regionally isolated to keloid-prone areas, such as the chest, ears, and deltoid regions, whereas the hands and feet are usually spared, which is why this case is meaningful.

PATIENT CONCERNS

A 20-year-old Chinese man had paronychia on both halluxes when he was 16 years old. He underwent a nail extraction at the age of 17. The nails of both halluxes were removed by nail extraction. This operation was successful, and the postoperative course was uneventful. After 6 months, the scars of the nail extraction on both sides began to exhibit hyperplasia and became red and swollen with itching. Later, the scar expanded and eroded the tissue beyond the matrix unguis. The whole matrix unguis was destroyed, and the nails were distorted. The scars began to ulcerate after 2 years. The patient used potassium permanganate to clean his wounds, but the keloid scars did not improve.

DIAGNOSES

The patient was diagnosed as toe keloid based on his history and symptoms. The biopsy result supported our diagnoses.

INTERVENTIONS

The toe keloids were effectively cured by surgical excision and skin flap transplantation combined with postoperative irradiation and hyperbaric oxygen (HBO) treatment.

OUTCOMES

No recurrence was detected during the period from 6 to 24 months of follow-up after the surgery.

LESSONS

In this case, the trauma of the nail extraction was likely the key cause of the keloid. However, the patient was also predisposed to keloids, as we observed keloids on his chest. In general, keloid tendencies appear to be regionally isolated to keloid-prone areas such as the chest, ears, and deltoid regions, whereas the hands and feet are usually spared, which is why this case is meaningful.

Risk factors of keloids in Syrians

Background

Keloid is a benign fibrous growth, which presents in scar tissue of predisposed individuals. It is a result of irregular wound healing, but the exact mechanism is unknown. However, several factors may play a role in keloid formation. To date, there are no studies of keloids in Syria, and limited studies on Caucasians, so we have investigated the risk factors of keloids in Syrians (Caucasians), and this is the main objective of this study.

Methods

Diagnosis of keloids was clinically made after an interview and physical examination. We did a histopathological study in case the physical examination was unclear.

The following information was taken for each patient; sex, Blood groups (ABO\Rh), cause of scarring, anatomical sites, age of onset, number of injured sites (single\multiple) and family history.

Results

We have studied the clinical characteristics of 259 patients with keloids,130 (50.2 %) females and 129 (49.8 %) males. There were 209 (80.7 %) patients with keloids in a single anatomical site compared to 50 (19.3 %) patients with 130 keloids in multiple anatomical sites, 253 (97.68 %) patients with keloids caused by a single cause for each patient compared to 6 (2.32 %) patients with keloids caused by two different causes for each patient.

Keloids could follow any form of skin injury, but burn was the most common (28.68 %). Also, keloids could develop at any anatomical sites, but upper limb (20 %) followed by sternum (19.17 %) was the most common. Over half of the patients developed keloids in the 11–30 age range. 19.3 % (50/259) of patients had family history, 76 % (38/50) of them had keloids located in the same anatomical sites of relative, also, 66 % (33\50) of them had keloids caused by the same cause.

The following information was found to be statistically significant; people with blood group A (p = 0.01) compared with other blood groups, spontaneous keloids in patients with blood group A (p = 0.01), acne in males (p = 0.0008) compared to females, acne in someone who has a previous acne keloid (p = 0.0002), burn in someone who has a previous burn keloid (p = 0.029), family history, especially for spontaneous (p = 0.005), presternal (p = 0.039) and shoulder (p = 0.008) keloids, people in second and third decades (p = 0.02) (p = 0.01) respectively.

Conclusion

Age of onset, sex, cause of scarring, blood groups, anatomical site, presence of family history and the number of site (multiple\single) were significant in keloid formation in Syrians.

Could 5-Fluorouracil or Triamcinolone Be an Effective Treatment Option for Keloid After Surgical Excision? A Meta-Analysis

PURPOSE

There is no universally accepted treatment regimen to decrease the recurrence rate of keloid formation after its removal, although many treatment options have been suggested. The purpose of this study was to investigate treatment options to prevent keloid recurrence after surgical excision.

MATERIALS AND METHODS

A systematic literature review and meta-analysis was performed using the Medline, Embase, and Cochrane databases. Predictor variables were 5-fluorouracil (5-FU) or triamcinolone adjuvant therapy, and the outcome variable was keloid recurrence rate. The Newcastle-Ottawa scale was used to assess the quality of the studies and the Cochrane risk-of-bias tool was used. Publication bias was evaluated using a funnel plot.

RESULTS

There were 1,224 publications identified; after screening, 5 were selected for review (1 retrospective cohort, 3 prospective cohorts, and 1 randomized controlled trial). The mean level of keloid recurrence was statistically lower in patients who received 5-FU compared with those who did not (control group; risk ratio, 0.18; 95% confidence interval [CI], 0.04 to 0.75). Triamcinolone was ineffective in lowering the keloid recurrence (risk difference, 0.06; 95% CI, -0.16 to 0.28).

CONCLUSION

5-FU can be considered an effective treatment to decrease keloid recurrence after surgical excision, although further research, including a randomized controlled trial, is required.

Endoscopic-Assisted Total Thyroidectomy via Lateral Keloid Scar Incision

Thyroidectomy is traditionally performed by the transcervical approach. To avoid or reduce visible scarring, diverse innovative surgical trials have been reported. Here we report a patient who underwent endoscopic thyroidectomy via a lateral keloid scar due to a previous traffic accident. A 30-year-old woman presented with a papillary thyroid carcinoma. Total thyroidectomy was performed via a keloid scar incision. The keloid scar was then revised. The total thyroidectomy was successful, resulting in no acute complications, such as neural injury, hematoma, or seroma formation. The keloid scar healed with excellent cosmetic results and the patient remains free of disease 12 months after excision. Endoscopic total thyroidectomy via a lateral keloid scar incision healed not only the physical disease but also the mental disease.

Follicular and scarring disorders in skin of color: presentation and management

Skin of color, also known as ethnic skin, is described as skin of individuals of African, Asian, Hispanic, Native-American, Middle Eastern, and Pacific Island backgrounds. Differences in hair morphology, hair grooming, cultural practices, and susceptibility to keloid scarring exist within these populations and have been implicated in hair, scalp, and skin disorders. Acne keloidalis (AK), central centrifugal cicatricial alopecia (CCCA), dissecting cellulitis of the scalp (DCS), pseudofolliculitis barbae (PFB), traction alopecia (TA), and keloids are the most prevalent follicular and scarring disorders in skin of color. They have been associated with disfigurement, permanent hair loss, emotional distress, and decreased quality of life. Hair grooming practices, such as the use of chemical relaxers, heat straightening, and tight braiding and weaving can cause scalp irritation and follicular damage and are linked to the pathogenesis of some of these conditions. Consequently, patient education and behavior modifications are integral to the prevention and management of these disorders. Scarring disorders are also of concern in ethnic populations. Keloid scarring is more prevalent in individuals of African, Asian, and Hispanic descent. The scarring alopecia CCCA is almost exclusively seen in patients of African descent. Therapeutic regimens such as intralesional corticosteroids, surgical excision, and laser therapy can be effective for these follicular and scarring disorders, but carry a risk of dyspigmentation and keloid scarring. Ethnic skin and hair may present unique challenges to the clinician, and knowledge of these differences is essential to providing quality care.

Sphingosine May Have Cytotoxic EffectsviaApoptosis on the Growth of Keloid Fibroblasts

Keloids are often resistant to treatment, causing much suffering to the patient. Our previous work found that ceramide (Cer) inhibits growth of fibroblasts via apoptosis. However, when compared to normal fibroblasts (NFs), which are quiescent, keloid fibroblasts (KFs) rapidly proliferate and are reported to be resistant to apoptosis via Cer. Sphingosine (Sph) is a metabolite product of ceramide that has some different biochemical properties. Thereofore, we investigated the cytotoxic effects of Sph on cultured fibroblasts from keloid lesions and normal skin in order to evaluate the possibility of using Sph in the treatment of keloid. We used the lactic dehydrogenase (LDH) method, MTT method, and propidium iodide (PI) method. Sph had cytotoxic effects via apoptosis on both the KFs and NFs. Our results indicate that Sph may be applicable to the future treatment of keloid.

Studying intense pulsed light method along with corticosteroid injection in treating keloid scars

BACKGROUND

Results of various studies suggest that the hypertrophic and keloid scars are highly prevalent in the general population and are irritating both physically and mentally.

OBJECTIVE

Considering the variety of existing therapies, intense pulsed light (IPL) method along with corticosteroid injection was evaluated in treating these scars.

MATERIALS AND METHODS

86 subjects were included in this clinical trial. Eight sessions of therapeutic intervention were done with IPL along with corticosteroid intralesional injection using 450 to 1200 NM filter, Fluence 30-40 J/cm2, pulse duration of 2.1-10 ms and palsed delay 10-40 ms with an interval of three weeks. To specify the recovery consequences and complication rate and to determine features of the lesion, the criteria specified in the study of Eroll and Vancouver scar scale were used.

RESULTS

The level of clinical improvement, color improvement and scar height was 89.1%, 88.8% and 89.1% respectively. The incidence of complications (1 telangiectasia case, 7 hyperpigmentation cases and 2 atrophy cases) following treatment with IPL was 11.6%. Moreover, the participants' satisfaction with IPL method was 88.8%.

CONCLUSIONS

This study revealed that a combined therapy (intralesional corticosteroid injection + IPL) increases the recovery level of hypertrophic and keloid scars. It was also demonstrated that this method had no significant side effect and patients were highly satisfied with this method.

Clinical characteristics of auricular keloids treated with surgical excision

Background and Objectives

Differences in morphology of auricular keloids possibly contribute to distinct results of treatment. The aim of this study was to evaluate clinical characteristics of the auricular keloids according to the modified Chang-Park classification and to compare the results of treatment including recurrence rate between the subgroups.

Subjects and Methods

Clinical data of 15 patients of auricular keloids were retrospectively reviewed. The keloids were classified according to modified Chang-Park classification. Clinical characteristics, the presence of recurrence, and the duration required for the recurrence were compared.

Results

Eight out of 15 patients (53.3%) were single sessile type (type II), followed by 4 patients of pedunculated type, 1 patient of multiple sessile type, 1 patient of buried type, and 1 patient of mixed type, respectively. Recurrent keloids after previous surgeries were noted in 7 out of 15 patients and most of them (6 of 7, 85.7%) were sessile type. Three patients who underwent surgery at our department showed recurrence.

Conclusions

The classification of auricular keloids according to morphologic patterns can assist surgeons in choosing the appropriate management.

Vaccine-associated fibrosarcoma with keloidal differentiation in a cat

A 6-year-old Domestic Shorthair cat was presented with a history of subcutaneous mass of the lateral left hind limb. The subcutaneous mass developed over a period of approximately 16 months subsequent to administration of Feline leukemia virus vaccines. Based on the histopathological and immunohistochemical examination, the subcutaneous mass was diagnosed as vaccine-associated fibrosarcoma with keloidal differentiation.

Insights gained from the reverse engineering of gene networks in keloid fibroblasts

Background

Keloids are protrusive claw-like scars that have a propensity to recur even after surgery, and its molecular etiology remains elusive. The goal of reverse engineering is to infer gene networks from observational data, thus providing insight into the inner workings of a cell. However, most attempts at modeling biological networks have been done using simulated data. This study aims to highlight some of the issues involved in working with experimental data, and at the same time gain some insights into the transcriptional regulatory mechanism present in keloid fibroblasts.

Methods

Microarray data from our previous study was combined with microarray data obtained from the literature as well as new microarray data generated by our group. For the physical approach, we used the fREDUCE algorithm for correlating expression values to binding motifs. For the influence approach, we compared the Bayesian algorithm BANJO with the information theoretic method ARACNE in terms of performance in recovering known influence networks obtained from the KEGG database. In addition, we also compared the performance of different normalization methods as well as different types of gene networks.

Results

Using the physical approach, we found consensus sequences that were active in the keloid condition, as well as some sequences that were responsive to steroids, a commonly used treatment for keloids. From the influence approach, we found that BANJO was better at recovering the gene networks compared to ARACNE and that transcriptional networks were better suited for network recovery compared to cytokine-receptor interaction networks and intracellular signaling networks. We also found that the NFKB transcriptional network that was inferred from normal fibroblast data was more accurate compared to that inferred from keloid data, suggesting a more robust network in the keloid condition.

Conclusions

Consensus sequences that were found from this study are possible transcription factor binding sites and could be explored for developing future keloid treatments or for improving the efficacy of current steroid treatments. We also found that the combination of the Bayesian algorithm, RMA normalization and transcriptional networks gave the best reconstruction results and this could serve as a guide for future influence approaches dealing with experimental data.

Molecular cloning, in vitro expression and bioactivity of rabbit transforming growth factor-beta receptor type II (rTGF-βRII)

Transforming growth factor-beta receptor II (TGF-βRII) is an attractive target for anti-scarring therapy in wound healing because it attenuates excessive TGF-β which has pleiotropic effects on the immune system. In the present study, the cDNA of rabbit TGF-βRII (rTGF-βRII) was amplified from rabbit peripheral blood by RT-PCR. The open reading frame of rTGF-βRII encodes a protein consisting of 567 amino acids, which contains a predicted transmembrane domain and a Serine/Threonine protein kinase domain similar to other identified mammalian TGF-βRIIs. The amino acid sequences of the biologically active, soluble rTGF-βRII and mouse, rat, human and chicken counterparts are 81%, 81%, 89% and 61%, respectively, identical. Recombinant soluble rTGF-βRII (rsTGF-βRII) fused with His tag was efficiently expressed in Escherichia coli BL21 (DE3) expression host strain. This fusion protein's molecular weight of ∼ 19 kDa was identified by SDS-PAGE and Western blotting. In vitro, purified rsTGF-βRII was able to inhibit the proliferation of keloid rabbit fibroblasts and decrease the level of collagen. These findings indicate that rTGF-βRII plays an important role in inhibiting the proliferation of keloid rabbit fibroblasts and provides the basis for investigations on the role of TGF-βRII in this important domestic species.

Acne scars: pathogenesis, classification and treatment

Acne has a prevalence of over 90% among adolescents and persists into adulthood in approximately 12%-14% of cases with psychological and social implications. Possible outcomes of the inflammatory acne lesions are acne scars which, although they can be treated in a number of ways, may have a negative psychological impact on social life and relationships. The main types of acne scars are atrophic and hypertrophic scars. The pathogenesis of acne scarring is still not fully understood, but several hypotheses have been proposed. There are numerous treatments: chemical peels, dermabrasion/microdermabrasion, laser treatment, punch techniques, dermal grafting, needling and combined therapies for atrophic scars: silicone gels, intralesional steroid therapy, cryotherapy, and surgery for hypertrophic and keloidal lesions. This paper summarizes acne scar pathogenesis, classification and treatment options.

Hepatoma-derived growth factor and its role in keloid pathogenesis

Hepatoma-derived growth factor (HDGF) is a novel mitogenic growth factor that has been implicated in many different carcinomas. Its role in keloid biology has not yet been investigated. The present study is aimed at examining the role of HDGF in keloid pathogenesis. Immunohistochemical staining and Western blot analyses were used to examine in vivo localization and expression of HDGF in keloid and normal skin tissue. This was followed by the detection of HDGF expression in fibroblasts cultured in vitro and fibroblasts exposed to serum. To investigate the effect of epithelial–mesenchymal interactions, a two-chamber system was employed in which keratinocytes on membrane inserts were co-cultured with the fibroblasts. HDGF expression levels in all cell extracts and conditioned media were assayed through Western blot analysis. In another set of experiments, the effect of exogenous recombinant HDGF on keloid fibroblasts (KF) and normal fibroblasts (NF) was examined. Cell proliferation was assessed by the MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) assay and by quantifying proliferating cell nuclear antigen (PCNA) expression. Downstream targets of HDGF were identified by detecting their expression through Western blot analysis. Our results indicate that there was an increase in HDGF expression in the dermis of keloid compared with normal skin tissue. The application of serum and epithelial–mesenchymal interactions did not seem to have any effect on intracellular HDGF expression levels. However, co-culturing keloid keratinocytes with KFs resulted in increased HDGF secretion when compared with monoculture or normal controls. Furthermore, treatment with exogenous recombinant HDGF was found to increase the proliferation of KFs, activate the extracellular signal-regulated kinase (ERK) pathway and up-regulate the secretion of vascular endothelial growth factor (VEGF).

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.

A novel truncated TGF-beta receptor II downregulates collagen synthesis and TGF-beta I secretion of keloid fibroblasts

Hypertrophic scars and keloid are dermal proliferative disorders in wound healing. Transforming growth factor beta (TGF-beta) has been implicated in scar formation through the activation of fibroblasts and the acceleration of collagen deposition. Our study aimed to design a novel truncated (27-123 residues) type II TGF-beta receptor (tTGFbetaRII) and to determine its effects on the proliferation of keloid fibroblasts and the collagen synthesis as well as TGF-beta I expression of the cells. The coding sequences of TGF-beta I and tTGFbetaRII were amplified using RT-PCR and then cloned into pGBKT7 and pGADT7 vectors. A yeast two-hybrid experiment and a glutathione S-transferase (GST)-pull down assay were performed to verify the affinity of tTGFbetaRII to TGF-beta I. Our results indicated that treatment with tTGFbetaRII inhibited the growth of keloid fibroblasts and suppressed the synthesis of type I collagen in keloid fibroblasts in a concentration-dependent manner. Moreover, northern and western blot analysis revealed a decline of the TGF-beta I expression at both mRNA and protein levels after exposure to 5, 10 or 20 mug/ml of tTGFbetaRII. Together, our data suggested that the exogenous tTGFbetaRII can efficiently trap TGF-beta I from access to wild-type receptors and can suppress TGF-beta I triggered signals. Thus it may potentially be clinically applied to scar therapy.

Biological Differences between Fibroblasts Derived from Peripheral and Central Areas of Keloid Tissues

BACKGROUND

Clinical observations indicate that the bulging and reddish peripheral areas of keloids are more elevated than their central areas. Moreover, the peripheral areas of keloids undergo aggressive growth and invasion into normal skin, beyond the boundaries of the initial wound. The aim of this study was to investigate the biological differences between peripheral and central keloid areas.

METHODS

Six patients suffering from keloids on the anterior chest were selected for this study. Fibroblasts were harvested from both central and peripheral keloid areas. Cell cycle distribution and apoptosis induction were analyzed by flow cytometry and with an antibody to Fas. The expression of apoptosis-related proteins (Fas, Bcl-2, and p53) was measured by flow cytometry.

RESULTS

Fibroblasts derived from both central and peripheral parts of keloids displayed significant resistance to Fas-mediated apoptosis. Analysis of cell cycle distribution indicated that approximately 60 percent of fibroblasts derived from the peripheral parts of keloids were in the proliferative periods of the cell cycle (G2 and S phase). However, the majority of fibroblasts derived from keloid centers were in G0 or G1 phase. Fas and Bcl-2 expression did not differ significantly between the two groups, but p53 expression was much higher in fibroblasts derived from central parts than from peripheral parts.

CONCLUSION

It is suggested that differences in cell cycle distribution and p53 protein expression may account for the different growth characteristics of keloid peripheries and centers.

Smallpox vaccination site complications

The typical resolution of the smallpox vaccination site is a smooth scar, a sequela that is discussed during prevaccination counseling. In addition, other types of lesion may develop at the scar site, including short- or long-term benign and malignant changes, as reviewed below. Although current recommendations do not discuss potential scar complications or scar surveillance, healthcare providers would benefit from an awareness of these potential complications, and should consider periodic scar surveillance as part of a general physical examination.

P38 MAP kinase mediates transforming growth factor-beta2 transcription in human keloid fibroblasts

Keloids are abnormal fibrous growths of the dermis that develop only in response to wounding and represent a form of benign skin tumor. Previous studies have shown increased protein levels of TGF-beta in keloid tissue, suggesting a strong association with keloid formation leading us to examine mechanisms for why it is more highly expressed in keloids. Here, we use serum stimulation as an in vitro model to mimic a component of the wound microenvironment and examine differential gene expression in keloid human fibroblasts (KFs) vs. normal human fibroblasts (NFs). Transcription of TGF-beta2 was rapid and peaked between 1 and 6 h after serum stimulation in KFs vs. NFs. We confirmed increased TGF-beta activity in the conditioned medium from KFs, but not NFs. Inhibition of second messenger signaling pathways demonstrated that only the p38 MAPK inhibitor SB-203580 could block upregulation of TGF-beta2 following serum stimulation in KFs. Immunoblotting demonstrated that p38 MAPK was phosphorylated within 15 min and was maintained at a high level in KFs but not in NFs. The transcription factors activating transcription factor-2 and Elk-1 are activated by p38 MAPK, and also showed rapid and prolonged phosphorylation kinetics in KFs but not in NFs. In conclusion, increased TGF-beta2 transcription in response to serum stimulation in KFs appears to be mediated by the p38 MAPK pathway. This suggests the mechanism of keloid pathogenesis may be due in part to an inherent difference in how the fibroblasts respond to wounding.

Epidemiology, aetiology and management of abnormal scarring: a review of the literature

Keloid and hypertrophic scars are the result of abnormal processes in scar formation. This paper reviews the literature and the many debates concerning the processes that cause abnormal scarring.

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.

Recombinant adenovirus-p21 attenuates proliferative responses associated with excessive scarring

Excessive cutaneous scarring is an important clinical disorder resulting in adverse tissue growth and function as well as undesirable cosmetic appearance. p21WAF-1/Cip-1 is a cyclin-dependent kinase inhibitor that blocks cell cycle progression and inhibits cell proliferation. We used a recombinant adenovirus containing the human p21WAF-1/Cip-1 cDNA (rAd-p21) to evaluate proliferative responses in skin models. In vitro dose-response studies using primary human dermal fibroblasts resulted in a dose-dependent expression of p21WAF-1/Cip-1 protein and a 3- to 80-fold reduction in cell proliferation as measured by 5-bromodeoxyuridine incorporation. Further, rAd-p21 reduced type I procollagen production when compared to control virus. A rat polyvinyl alcohol sponge model was used to determine rAd-p21 effects on granulation tissue formation in vivo. Sponges pretreated with a granulation tissue stimulator, rAd-PDGF-B and subsequently rAd-p21 on a second injection, showed a p21WAF-1/Cip-1 specific dose-dependent decrease in percent granulation fill as the rAd-p21 dose increased (p < 0.001). Immunohistochemistry identified human p21WAF-1/Cip-1 expression in sponges treated with rAd-p21 5 days postinjection. Additionally, 5-bromodeoxyuridine and Ki67 staining in sponges treated with rAd-p21 showed a significant decrease in proliferation when compared to rAd-platelet-derived growth factor-B alone or vehicle control groups (p < 0.01). These data support the utility of p21WAF-1/Cip-1 in targeting hyperproliferative disorders of the skin.

Histopathological Differential Diagnosis of Keloid and Hypertrophic Scar

Distinguishing hypertrophic scar (HS) from keloid histopathologically is sometimes difficult because thickened hyalinized collagen (keloidal collagen), the hallmark of keloid, is not always detectable and alpha-smooth muscle actin (alpha-SMA), a differentiating marker of HS, is variably expressed in both forms of scar. The aim of this study was to investigate additional distinguishing features to facilitate differentiation between keloid and HS. We compared various histologic features and the expression of alpha-SMA in 40 specimens of keloid and 10 specimens of HS. The features more commonly seen in keloids were: (a) no flattening of the overlying epidermis, (b) no scarring of the papillary dermis, (c) presence of keloidal collagen, (d) absence of prominent vertically oriented blood vessels, (e) presence of prominent disarray of fibrous fascicles/nodules, (f) presence of a tongue-like advancing edge underneath normal-appearing epidermis and papillary dermis, (g) horizontal cellular fibrous band in the upper reticular dermis, and (h) prominent fascia-like fibrous band. The last three features were found in keloid specimens only, including the ones lacking detectable keloidal collagen. Our study confirmed the diagnostic value of keloidal collagen, but it was only found in 55% of keloid specimens. Alpha-SMA expression was found in both HS (70%) and keloid (45%), thus it would not be a differentiating marker. In scars with no detectable keloidal collagen, the presence of the following feature(s) favors the diagnosis of keloid: non-flattened epidermis, non-fibrotic papillary dermis, a tongue-like advancing edge, horizontal cellular fibrous band in the upper reticular dermis, and prominent fascia-like band.

Complex epithelial-mesenchymal interactions modulate transforming growth factor-beta expression in keloid-derived cells

Keloids are proliferative dermal growths representing a pathologic wound healing response. We have previously demonstrated that coculture of fibroblasts derived from either keloid or normal skin have an elevated proliferation rate when cocultured with keloid-derived keratinocytes vs. normal keratinocytes. In these studies, we examined the contribution of transforming growth factor-beta (TGF-beta) to this phenomenon using a two-chamber coculture system. Fibroblast proliferation in coculture was slower with the addition of a pan-TGF-beta neutralizing antibody. Keloid keratinocytes in coculture expressed more TGF-beta1, -beta3, and TGF-beta receptor 1 than normal keratinocytes. Keloid fibroblasts cocultured with keloid keratinocytes expressed more mRNA for TGF-beta1, -beta2, TGF-beta receptor 1, and Smad2. Keloid fibroblasts also produced more type I collagen, connective tissue growth factor, and insulin-like growth factor-II/mannose-6-phosphate receptor when cocultured with keloid keratinocytes vs. normal keratinocytes. Levels of total and activated TGF-beta activity increased when fibroblasts were cocultured with keratinocytes, correlating with the changes in transcriptional activity of TGF-beta. In conclusion, we find a complex paracrine interaction regulates TGF-beta mRNA expression and activation between keratinocytes and fibroblasts. These data suggest that keloid pathogenesis may result from both an increased TGF-beta production and activation by the keloid keratinocyte, and elevated TGF-beta expression, utilization, and signaling in keloid fibroblasts.

Combination of Surgery and Intralesional Verapamil Injection in the Treatment of the Keloid

Keloid scars are one of the most challenging problems for physicians and surgeons. These scars have been treated in many ways, with varying success. Verapamil is a widely used calcium channel antagonist, and it has been shown that calcium channel blockers inhibit the synthesis/secretion of extracellular matrix molecules, including collagen, glycosaminoglycans, and fibronectin, and increase collagenase. In this study, we performed total keloid excision in combination with reconstruction with W-plasty or skin grafting and injection of verapamil hydrochloride into the lesions of 21 patients with keloids. Patients were followed for minimum of 2 years, and the treatment outcome was evaluated based on the cosmetic appearances, symptomatic improvements, and the results of microscopic examinations. Also, patient satisfaction was scored with a visual analog scale. Two years after the operations, two patients had keloid in lesser diameter than the original lesions, two patients had lesions that were hypertrophic scars in appearance, and four patients had pruritus. One patient had keloid on the donor site. The rate of patient satisfaction was 6.4 on a scale of 1 to 10. We reviewed the treatment of keloid in this study and obtained one of the lower rates of complication in the literature. We believe that surgical excision with W-plasty or skin grafting and intralesional verapamil injection may be a good alternative in the treatment of keloid.

Treatment of scars with Er:YAG laser in patients with cleft lip: a preliminary report

OBJECTIVE

Although one goal in cleft lip surgery is to avoid serious scarring, residual scars are often observed after primary surgery. The goal of this preliminary report was to present the standardized application of laser technology to reduce the appearance of residual scars.

DESIGN

Ten patients with scarring after unilateral and bilateral cleft lip surgery were treated with a Dual Mode erbium yttrium-aluminum-garnet laser. This laser was recently introduced and had been used only for cosmetic applications, skin resurfacing, and correction of acne scars.

RESULTS

An improvement in the clinical appearance of the laser-treated scars was observed after the first treatment, with continued improvement after the second laser session. The clinically observed improvements were corroborated by the patients' reports concerning satisfaction with the result.

CONCLUSIONS

The combined mechanisms of ablation/coagulation and shrinking of the skin caused by the laser, in addition to observed patient satisfaction and low risk associated with the procedure, suggest that this treatment approach can be effective in the correction of residual scarring in patients with cleft lip.