Study of 1,000 patients with keloids in South India

Risk factors associated with the progression from mild keloids to severe mild keloids

Background:

Keloids are benign fibrous growths that are caused by excessive tissue build-up. Severe keloids exert more significant effects on patients’ quality of life than do mild keloids. We aimed to identify factors associated with the progression from mild keloids to severe keloids, as distinct from those associated with the formation of keloids.

Methods:

In this retrospective case-control study, 251 patients diagnosed with keloids at West China Hospital between November 2018 and April 2021 were grouped according to the severity of lesions (mild [n = 162] or severe [n = 89]). We collected their basic characteristics, living habits, incomes, comorbidities, and keloid characteristics from Electronic Medical Records in the hospital and the patients’ interviews. Conditional multivariable regression was performed to identify the independent risk factors for the progression of keloids.

Results:

Eighty-nine patients (35.5%) were classified as having severe keloids. We found the distribution of severe keloids varied with sex, age, excessive scrubbing of keloids, family income, the comorbidity of rheumatism, disease duration, characteristics of the location, location in sites of high-stretch tension, the severity and frequency of pain, the severity of pruritus, and infection. Multivariable analysis revealed significant associations between severe keloids and infection (odds ratio [OR], 3.55; P = 0.005), excessive scrubbing of keloids (OR, 8.65; P = 0.001), low or middle family income (OR, 13.44; P = 0.021), comorbidity of rheumatism (OR, 18.97; P = 0.021), multiple keloids located at multiple sites (OR, 3.18; P = 0.033), and disease duration > 15 years (OR, 2.98; P = 0.046).

Conclusion:

Doctors should implement more active and thorough measures to minimize the progression of mild keloids in patients who have any of the following risk factors: infection, excessive scrubbing of keloids, low or middle family income, comorbidity of rheumatism, multiple keloids located at multiple sites, and disease duration > 15 years.

A Case of Scapular Hidradenoma Treated as a Keloid

Hidradenomas are relatively rare benign tumors in the dermis that differentiate into eccrine or apocrine sweat glands. They often present as round or oval nodules and vary in color. Generally, they occur in the head and neck region. Keloid scars are often red, elevated lesions that are caused by chronic inflammation in the reticular dermis. These scars demonstrate a preference for high skin-tension sites, including the scapular region. Herein, we describe a case of a dark red hidradenoma on the scapular region with a high incidence of acne surrounding the lesion area that was initially diagnosed as an acne-initiated keloid. However, local steroid injection did not cure the lesion. After excision, histopathology revealed typical findings for hidradenoma, namely mucinous, polygonal, and clear cell composition. In some cases, as presented it may be challenging for clinicians to differentiate between hidradenoma and keloid due to the similar clinical features. Thus, hidradenoma should be taken in consideration as a differential diagnosis when encountering steroid-refractory keloid-like lesions. Moreover, early biopsy or surgical resection should be considered.

Efficacy of Surgical Excision and Brachytherapy in the Treatment of Keloids: A Retrospective Cohort Study

OBJECTIVE

To demonstrate the efficacy of a protocol combining surgical excision and high-dose-rate brachytherapy for treatment of keloids.

METHODS

The authors performed a unicentric retrospective cohort study between 2013 and 2018. The minimum follow-up was 12 months. All patients treated for keloids at the authors' institution were included. Extralesional excision was performed with placement of a brachytherapy sheath under the skin. The total dose of irradiation was 18 Gy. The postoperative results were evaluated for aesthetic and functional outcomes with a validated scale, as well as the presence or absence of recurrence.

RESULTS

Fifteen patients were lost to follow-up. Thirty-eight patients with 67 keloids were included. The control rate was 94%. The aesthetic and functional outcomes were considered good in 62% of cases. The main limitation of the study was the small patient population.

CONCLUSIONS

Extralesional excision combined with postoperative high-dose-rate brachytherapy seems to be one of the most effective invasive protocols to treat and prevent keloids.

Current Advances in Hypertrophic Scar and Keloid Management

Hypertrophic scars and keloids are caused by excessive tissue response to dermal injury due to local fibroblast proliferation and collagen overproduction. This response occurs because of pathologic wound healing due to dysregulation in the inflammatory, proliferative, and/or remodeling phase. Patients with hypertrophic scars or keloids report reduced quality of life, physical status, and psychological health. Hypertrophic scars or keloids will develop in 30 to 90% of individuals, and despite their prevalence, treatment remains a challenge. Of the treatments currently available for hypertrophic scars and keloids few have been adequately supported by studies with appropriate experimental design. Here, we aim to review the available literature to provide up-to-date information on the etiology, epidemiology, histology, pathophysiology, prevention, and management options available for the treatment of hypertrophic scars and keloids and highlight areas where further research is required.

A hesitated approach: primary radiotherapy for keloids-a case series

PURPOSE

To assess the efficacy and toxicity of hypofractionated radiotherapy (RT) alone in treatment-resistant symptomatic keloids.

METHODS

Six patients with a total of 13 inoperable large keloid lesions and no response to previous treatments were admitted to our department between 2017 and 2019. All patients were examined for detailed wound localization, size, contour, and color assessment, and for objective and subjective symptoms. Response to treatment was graded as "complete remission" in case of full symptomatic relief and >75% decrease in lesion size, as "partial remission" in case of partial symptomatic relief and 25-75% decrease in lesion size, and as "stable disease" in case of no symptomatic relief or <25% decrease in lesion size. Patients were followed up monthly for the first 3 months and every 3 months thereafter by physical examination.

RESULTS

A total dose of 37.5 Gy external RT in five fractions was prescribed by 6‑MeV electrons in 4 patients and 6‑MV photons in 2 patients. Complete response was obtained in all patients at the 6‑month control. All patients were satisfied with cosmetic results at their last control. Grade 2 dermatitis developed in all patients during the second week of RT but resolved completely in all after 6 months following the end of RT.

CONCLUSION

In keloids that are unresponsive to standard treatment, hypofractionated RT using a total dose of 37.5 Gy in five fractions is feasible.

MicroRNA-21 may be involved in the therapeutic effects of Galla chinensis ointment on keloid

Objective

Galla chinensis ointment can inhibit the proliferation of keloid fibroblasts and decrease keloid formation. We investigated whether Galla chinensis ointment inhibits keloid fibroblast proliferation through expression of microRNA-21, phosphorylated (p)-phosphatidylinositol 3-kinase (p-PI3K), chromosome 10 neutropenic protein phosphatase (PTEN), protein kinase B (p-Akt), and mammalian target of rapamycin (p-mTOR).

Methods

A keloid mouse model and human keloid-derived fibroblasts were developed and treated with Galla chinensis. Immunohistochemistry, western blot, and reverse transcription-PCR were used to detect miR-21, PI3K, PTEN, Akt, and mTOR in keloid tissues.

Results

p-Akt and p-mTOR were highly expressed in the control group, PTEN was highly expressed in the treatment group, and p-PI3K was highly expressed in keloid tissue in both groups. Galla chinensis reduced miR-21 expression and increased PTEN mRNA expression in keloid fibroblasts compared with the control group, resulting in increased PTEN protein and decreased p-Akt and p-mTOR protein. Galla chinensis had no effect on p-PI3K.

Conclusion

Galla chinensis might inhibit proliferation of keloid fibroblasts by upregulating PTEN, thus inhibiting expression of miR-21 and downregulating p-Akt and p-mTOR expression. These results confirm the effect of Galla chinensis ointment on fibroblasts and suggest that it could be used to manage keloids clinically.

Contemporary treatment of keloids: A 10-year institutional experience with medical management, surgical excision, and radiation therapy

INTRODUCTION

We evaluate a single center's, decade-long experience utilizing 3 approaches to keloid treatment: corticosteroid medical management (MM), surgical excision (SE), and surgical excision + radiation therapy (SE + RT).

STUDY DESIGN

Patients undergoing keloid treatment were identified (2008-2017). Outcomes were symptomatology/cosmesis for MM, and recurrence and complications for SE and SE + RT. Logistic regression was used to determine factors associated with recurrence and complications.

RESULTS

284 keloids (95 MM, 94 SE, 95 S E + RT) corresponded to patients with a median age of 39.1 (IQR: 26.1-53), 68.1% Black, and followed-up for 15.4 months (IQR: 5.6-30.7). For MM, 84.6% and 72.5% reported improvement in cosmesis and symptoms, respectively. SE and SE + RT recurrence were 37.2 and 37.9%, respectively. In adjusted analyses, higher radiation doses were associated with decreased recurrence whereas male gender (OR 3.3) and postoperative steroids (OR 9.5) were associated with increased recurrence (p < 0.01). There were more complications in the SE + RT group.

CONCLUSIONS

MM resulted in at least some improvement. Recurrence rates after SE and SE + RT were similar. Female sex is protective, race does not affect outcomes.

Understanding Keloid Pathobiology From a Quasi-Neoplastic Perspective: Less of a Scar and More of a Chronic Inflammatory Disease With Cancer-Like Tendencies

Keloids are considered as benign fibroproliferative skin tumors growing beyond the site of the original dermal injury. Although traditionally viewed as a form of skin scarring, keloids display many cancer-like characteristics such as progressive uncontrolled growth, lack of spontaneous regression and extremely high rates of recurrence. Phenotypically, keloids are consistent with non-malignant dermal tumors that are due to the excessive overproduction of collagen which never metastasize. Within the remit of keloid pathobiology, there is increasing evidence for the various interplay of neoplastic-promoting and suppressing factors, which may explain its aggressive clinical behavior. Amongst the most compelling parallels between keloids and cancer are their shared cellular bioenergetics, epigenetic methylation profiles and epithelial-to-mesenchymal transition amongst other disease biological (genotypic and phenotypic) behaviors. This review explores the quasi-neoplastic or cancer-like properties of keloids and highlights areas for future study.

Multimodal investigation of a keloid scar by combining mechanical tests in vivo with diverse imaging techniques

Keloids are pathologic scars, defined as fibroproliferative diseases resulting from abnormal wound responses, which grow beyond the original wound margins. They develop on specific pro-keloid anatomic sites frequently characterized by high stress states. The initiation and growth mechanisms of keloid are not well-understood. This study relates multimodal investigation of a keloid by using mechanical tests in vivo and imaging techniques. A single case composed of a keloid, the healthy skin surrounding the keloid, and the contralateral healthy skin on the upper arms of a woman has been investigated in extension and suction by using non-invasive devices dedicated to in vivo skin measurement. The thickness and microstructure of these soft tissues have been observed by echography, tomography and confocal microscopy. Displacement fields have been obtained by using digital image correlation. Unlike healthy skin, keloid is not a well-defined multilayer structure: the frontier between epidermis and dermis disappears. The mechanical behavior of keloid is highly different from healthy skin one. The R-parameters have been deduced from suction curves. Physical parameters as tissue extensibility, initial and final tangent moduli have been identified from the stress-strain curves. The extensibility (respectively, initial rigidity) of keloid is highly lower (respectively, higher) than that of healthy skin. To compare the final rigidity of keloid versus healthy skin, further tests have to be performed with higher strain values.

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.

Current Understanding of the Genetic Causes of Keloid Formation

Keloids are an exuberant response to cutaneous wound healing. Several lines of evidence suggest that keloid scarring is influenced by genetic factors. This review will discuss our current understanding of genetic influences on keloidal scarring via familial inheritance patterns; ethnic differences in prevalence; syndromes with keloid occurrence; linkage analysis, genome-wide association studies, and admixture mapping studies; transforming growth factor beta and p53 variant studies; and human leukocyte antigen polymorphisms.

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.

The Role of Topical Vitamin E in Scar Management: A Systematic Review

BACKGROUND

The practice of prescribing vitamin E after surgery for scar prevention and treatment is widespread and increasingly popular among both the public and clinicians. However, very little evidence exists for this "ritual."

OBJECTIVES

This review was undertaken to critically analyze the current literature about the effect of vitamin E on treating scars.

METHODS

The Cochrane, Medline, and PubMed databases were searched based on the Preferred Reporting Items for Systematic Review and Meta-Analysis Protocols (PRISMA-P). The studies and levels of recommendation were graded according to the American Society of Plastic Surgeons (ASPS) criteria. Only prospective studies were included.

RESULTS

Only six studies met the inclusion criteria. Of these six included studies, three reported a significant improvement in the cosmetic appearance of scars when using vitamin E: one study used topical vitamin E in white children as monotherapy, and two studies used vitamin E in an adult population as combination therapy. The other three selected studies showed no significant improvement in scar appearance when using topical vitamin E as monotherapy. Two of the six included studies reported adverse events of vitamin E application: contact dermatitis and increased incidence of itching and rash.

CONCLUSIONS

We conclude that there is not yet sufficient evidence that monotherapy with topical vitamin E has a significant beneficial effect on scar appearance to justify its widespread use. Further prospective studies with vitamin E monotherapy and/or combination therapy are warranted to draw better conclusions regarding the value of vitamin E in the management of scar healing.

LEVEL OF EVIDENCE

2 Therapeutic.

Currently known risk factors for hypertrophic skin scarring: A review

OBJECTIVE

The study aims to provide an overview of risk factors for hypertrophic scarring.

BACKGROUND

Hypertrophic skin scarring remains a major concern in medicine and causes considerable morbidity. Despite extensive research on this topic, the precise mechanism of excessive scarring is still unknown. In addition, the current literature lacks an overview of the possible risk factors in the development of hypertrophic scars.

METHODS

PubMed searches were performed on risk factors for hypertrophic scar (HTS) formation.

RESULTS

Eleven studies suggesting nine factors associated with HTS formation were found. Studies concerning chemotherapy, age, stretch, infection, and smoking have a moderate to high strength of evidence, but some other factors have not been studied in a convincing manner or are still disputed.

CONCLUSIONS

Risk factors for HTS formation are young age, bacterial colonization, and skin subjected to stretch. Chemotherapy, statins, and smoking seem to play a protective role in HTS formation.

Clinical implications of single- versus multiple-site keloid disorder: a retrospective study in an Asian population

BACKGROUND

There is strong evidence of genetic susceptibility in individuals with keloid disorder. The purpose of this cross-sectional study was to determine the clinical relevance of our proposed variables on the multiplicity of keloids by further investigating the presence of other keloids and a family history.

METHODS

This was a retrospective review, using institutional review board-approved questionnaires, of patients with keloids who were seen at Kangbuk Samsung Hospital between December 2002 and February 2010. Eight hundred sixty-eight patients were included in our study. Comparisons between the 2 groups were made using Mann-Whitney tests for continuous variables and χ2 tests for categorical variables.

RESULTS

In our patient group, younger age of onset and the presence of family history were significantly associated with the occurrence of keloids at multiple sites. The locations of extra-auricular keloids, in order of frequency, included the shoulder; anterior chest, including the breasts; deltoid; trunk and pubic area; upper extremities; lower extremities; and other sites. As compared to secondary keloids, primary keloids were significantly associated with both a lower degree of recurrence and the presence of other keloids. The presence or absence of family history was significantly associated with the presence or absence of other keloids and primary or secondary keloids.

CONCLUSIONS

Keloid disorder is one of the most frustrating problems in wound healing and advances in our understanding of the differences of occurrence at a single site versus multiple sites might help in understanding pathogenesis and improving treatment.

Postoperative brachytherapy and electron beam irradiation for keloids: A single institution retrospective analysis

The aim of the present study was to perform a retrospective analysis of the control rate and toxicity of postoperative brachytherapy and electron beam irradiation for keloids. A retrospective review was performed of 116 keloid patients who underwent postoperative brachytherapy and electron beam irradiation between January 1, 2002 and June 30, 2012. Several different radiotherapy techniques and fractionation schedules were performed in the analysis, including high-dose rate (HDR) irradiation with 192Ir at 8 Gy/1 fraction (F)+9 Gy/3F or 20 Gy/4F; HDR brachytherapy with 60Co at 20 Gy/4F or 18 Gy/6F; or external beam electron therapy at 26 Gy/13F or 30 Gy/15F. The endpoints of the study were analysis of the control rate and toxicity. The median observation period was 46.5 months (range, 10.0-120.0 months) for all patients. In total, 18 of the 116 patients relapsed, and 16.7 months (range, 10.0-30.0 months) was the median time to recurrence for these patients. The control rates for the patients who received hypofractionation (>2 Gy per fraction) and conventional fraction (2 Gy per fraction) were 88.5 and 76.3%, respectively (P=0.043). The control rates for the patients whose calculated biological effective doses (BED) were >30 Gy and <30 Gy were 89.7 and 79.3%, respectively (P=0.104). There were no grade 2 or higher adverse effects based on the Common Terminology Criteria for Adverse Events v3.0 in the late phase. No evidence was identified for a link between radiotherapy and the subsequent occurrence of cancer. The results of the present study indicate that hypofractionated radiotherapy played an important role as an adjuvant therapy following surgical excision of keloids. A BED of >30 Gy appears to be sufficient. No definitive evidence was found for an association between radiotherapy and the occurrence of cancer during the follow-up, however, more cases and longer follow-up periods are required.

Clinical and epidemiological analysis of keloids in Chinese patients

Keloids are common abnormally raised fibroproliferative lesions that can occur following even minor cutaneous trauma. There are limited data on Chinese patients with keloids, and the purpose of our study was to investigate the clinical and epidemiological features of keloids in Chinese patients. Assessment was performed by unified, designed questionnaires. A total of 715 patients were enrolled and statistical analysis and heritability were performed using EPI INFO 6.0, SPSS13.0 and Falconer's method. Keloids occurred typically between the ages of 10 and 30 years, and the mean age of initial onset was 21.14 ± 13.45 years in females and 22.55 ± 11.36 years in males. The difference in the mean age of onset was not significant between males and females (p > 0.05). A greater severity of keloids was observed in the positive history family group than in the negative history family group, and this difference was statistically significant (χ (2) = 10.889, p < 0.05). The formation of keloids in multiple anatomical sites was found to be significant in the positive family history group. This difference was statistically significant (χ (2) = 15.47, p < 0.001). The prevalence of keloids in first-, second- and third-degree relatives of the proband with keloids was 7.62, 0.38 and 0.035 %, respectively. These results were higher than those in controls and the difference of the prevalence rates of first- and second-degree relatives between probands and controls was significant (χ (2) = 224.63 and 12.078, respectively, p < 0.001). The heritability of keloids in first-, second- and third-degree relatives was 72.45, 40.55 and 17.07 %, respectively. Our findings revealed that the most severe forms of keloids were observed in the probands with positive family history, and the heritability in first-degree relatives of probands was 72.45 %. It is certain, therefore, that genetic factors play a role in the hereditary composition of keloids.

Keloids in Rubinstein-Taybi syndrome: a clinical study

BACKGROUND

Rubinstein-Taybi syndrome (RSTS) is a multiple congenital anomalies-intellectual disability syndrome. One of the complications is keloid formation. Keloids are proliferative fibrous growths resulting from excessive tissue response to skin trauma.

OBJECTIVES

To describe the clinical characteristics of keloids in individuals with RSTS reported in the literature and in a cohort of personally evaluated individuals with RSTS.

PATIENTS AND METHODS

We performed a literature search for descriptions of RSTS individuals with keloids. All known individuals with RSTS in the Netherlands filled out three dedicated questionnaires. All individuals with (possible) keloids were personally evaluated. A further series of individuals with RSTS from the U.K. was personally evaluated.

RESULTS

Reliable data were available for 62 of the 83 Dutch individuals with RSTS and showed 15 individuals with RSTS (24%) to have keloids. The 15 Dutch and 12 U.K. individuals with RSTS with keloids demonstrated that most patients have multiple keloids (n > 1: 82%; n > 5: 30%). Mean age of onset is 11·9 years. The majority of keloids are located on the shoulders and chest. The mean length × width of the largest keloid was 7·1 × 2·8 cm, and the mean thickness was 0·7 cm. All affected individuals complained of itching. Generally, treatment results were disappointing.

CONCLUSIONS

Keloids occur in 24% of individuals with RSTS, either spontaneously or after a minor trauma, usually starting in early puberty. Management schedules have disappointing results. RSTS is a Mendelian disorder with a known molecular basis, and offers excellent opportunities to study the pathogenesis of keloids in general and to search for possible treatments.

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.

Keloid incidence in Asian people and its comorbidity with other fibrosis-related diseases: a nationwide population-based study

Keloids is a fibroproliferative disease. The incidence of keloids among Asians has not been thoroughly studied. The objective of this study is to determine the incidence of keloids in Taiwan, which mainly consists of ethnic Chinese. Furthermore, we want to determine the comorbidity rate of other fibrosis-related diseases among keloid patients. This study was based on the National Health Insurance Research Database, which contains the data of 1 million randomly selected patients. Multivariate logistic regression analyses were employed to estimate the relative odds of keloids as a function of fibrosis-related diseases. The annual keloid incidence rate in Taiwan was 0.15 % for the general population. With a 1.33 ratio, women outnumbered men. Women with uterine leiomyoma have a 2.25-fold greater risk of keloids, compared with women without leiomyoma. We concluded that keloid incidence in Taiwan is approximately 0.15 %. Women with leiomyoma have a greater risk of keloids, this implicates that both diseases share a common etiopathological pathway.

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

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

[Adjuvant treatment of keloid scars: electrons or brachytherapy?]

PURPOSE

Evaluation of perioperative treatment of keloid scars with electron beam therapy or iridium 192 low dose rate brachytherapy.

PATIENTS AND METHODS

From 1994 to 2010, 95 patients with 142 keloid scars have been treated by immediate perioperative irradiation and retrospectively reviewed in our institute: 116 scars were treated by electrontherapy and 26 by brachytherapy.

RESULTS

In the electrontherapy group treated locations were: earlobe (n=88, 76%), thorax (n=14, 12%), neck (n=9, 8%), limbs (n=5, 4%). The median size of lesions was 3cm (range [R]: 0.5-18cm). In 95.6% of cases, a dose of 15Gy was delivered in five fractions of 3Gy. The median follow-up was 70 months (R: 7-161 months). The 2-year and 5-year local control were respectively 69% (95% confidence interval [95% CI]: 59-76%) and 55% (95% CI: 45-64%). In the brachytherapy group treated locations were: neck (n=3, 11%), earlobe (n=8, 32%), abdomen (n=3, 11%), thorax (n=2, 8%), limbs (n=10, 38%). The median size of lesions was 6.6cm (R: 1.7-28cm). The median dose delivered at 5mm from the source was 20Gy (R: 15-20.69). The median follow-up was 113 months (R: 21-219 months). The 2-year and 5-year local control were respectively 84.6% (95% CI: 64-94%) and 73.5% (95% CI: 49-87%). So far, no radiation-induced cancer has occurred. A trend to a better local control with brachytherapy was noted (compared to electrontherapy, 2-year relapse is halved with brachytherapy) though this difference did not reach the significance (P=0.0991), probably due to the reduced number of patients in the brachytherapy group.

CONCLUSION

Brachytherapy seems to provide better local control compared to electrontherapy, and should be proposed as first line treatment. However, electrontherapy is an interesting alternative in case of difficulty to realize brachytherapy. There is probably a dose effect: according to published data, 25 to 30Gy should at least be proposed.

Is There an Association between Keloids and Blood Groups?

Objective. The aim of the study is to investigate the possible associations between the blood groups ABO and Rhesus systems and the presence of keloids in patients with black skin. Method. This case-control study was conducted between September 2007 and August 2011 comparing dermatologic outpatients with keloids to matched controls recruited in preanesthetic consultation at Tokoin Teaching Hospital of Lomé (Togo). Results. The distribution of different ABO blood groups and Rhesus blood groups in both groups (cases versus controls) was not significantly different. This distribution of different blood groups was superimposed on the general population of blood donors at the National Blood Transfusion Center of Lomé. Univariate analysis between each blood group and the presence of keloid does not yield any statistically significant association between blood groups and presence of keloids in the subjects. Conclusion. The study shows no significant association between blood groups and the presence of keloids in our patients. Further investigation needs to be conducted to elucidate this hypothesis further by conducting multicenter studies of several ethnic groups.

Keloid scarring: understanding the genetic basis, advances, and prospects

Keloid disease is a fibroproliferative dermal tumor with an unknown etiology that occurs after a skin injury in genetically susceptible individuals. Increased familial aggregation, a higher prevalence in certain races, parallelism in identical twins, and alteration in gene expression all favor a remarkable genetic contribution to keloid pathology. It seems that the environment triggers the disease in genetically susceptible individuals. Several genes have been implicated in the etiology of keloid disease, but no single gene mutation has thus far been found to be responsible. Therefore, a combination of methods such as association, gene-gene interaction, epigenetics, linkage, gene expression, and protein analysis should be applied to determine keloid etiology.

Hypertrophic scarring and keloids: pathomechanisms and current and emerging treatment strategies

Excessive scars form as a result of aberrations of physiologic wound healing and may arise following any insult to the deep dermis. By causing pain, pruritus and contractures, excessive scarring significantly affects the patient's quality of life, both physically and psychologically. Multiple studies on hypertrophic scar and keloid formation have been conducted for decades and have led to a plethora of therapeutic strategies to prevent or attenuate excessive scar formation. However, most therapeutic approaches remain clinically unsatisfactory, most likely owing to poor understanding of the complex mechanisms underlying the processes of scarring and wound contraction. In this review we summarize the current understanding of the pathophysiology underlying keloid and hypertrophic scar formation and discuss established treatments and novel therapeutic strategies.

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

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

A radiobiological analysis of multicenter data for postoperative keloid radiotherapy

PURPOSE

To identify factors significantly affecting recurrence rates after postoperative external beam radiotherapy (XRT) of keloids, and to delineate any radiation dose response and effects of radiation dose per fraction.

METHODS AND MATERIALS

A comprehensive literature review was performed to compile a database of 2,515 resected keloids (36.9% earlobe). Postoperative XRT was 45- to 100-kV X-rays in 27.0% or 120- to 250-kV X-rays in 11.1%, Co-60 in 1.9%, Sr-90 in 4.7%, 1.5- to 9-MeV electrons in 26.5%, and no XRT in 28.8%. In the 1,791 irradiated patients, the median radiation parameters were as follows: total dose, 15 Gy (range, 6-30 Gy); dose per fraction, 5.0 Gy (range, 2-15 Gy); fractions, 3 (range, 1-10); and time, 7 days (range, 0-33 days).

RESULTS

Multivariate stepwise logistic regression correlated decreased keloid recurrence with earlobe location (p = 1.98E-10; odds ratio, 0.34), biologically effective dose (p = 1.01E-27), and treatment with electron beam or Co-60 vs. other techniques (p = 0.0014; odds ratio, 0.72). Different radiobiological models calculated values of α/β = 1.12 to 2.86 (mean, 2.08) and time (repopulation) correction factors for biologically effective dose from 0.98 to 2.13 Gy per day (mean, 1.34) starting 10 days after surgery. Different models (with α/β = 2.08) predicted that doses needed for 90% and 95% control with 3 fractions of postoperative electron beam were 16.0 to 16.2 Gy and 18.3 to 19.2 Gy, respectively, in less than 10 days for earlobe keloids and 21.5 to 22.2 Gy and 23.4 to 24.8 Gy, respectively, in less than 10 days for other sites.

CONCLUSIONS

Postoperative keloid radiotherapy requires moderately high doses and optimal technique to be effective. The relatively low α/β ratio indicates that radiotherapy with a limited number of fractions and high doses per fraction is the best strategy.

595-nm long pulsed dye laser and 1450-nm diode laser in combination with intralesional triamcinolone/5-fluorouracil for hypertrophic scarring following a phenol peel

Hypertrophic scars and keloids are a therapeutic challenge because of the low response to treatment and recurrences after treatment. A variety of treatment regimens have been used with different degrees of success, with no universally accepted treatment protocol resulting in their complete and permanent resolution. We offer this case to demonstrate a combination approach for the treatment of hypertrophic scarring. A 75-year-old woman (with Fitzpatrick skin type II) presented with a 4-month history of scarring, which had developed following a phenol peel for perioral rhytides. The patient underwent 10 treatment sessions with the 595-nm long-pulsed dye laser followed immediately by the 1450-nm diode laser in combination with intralesional triamcinolone and 5-fluorouracil. After the fifth treatment session, about 90% improvement was noted; at the last treatment session, greater than 95% overall improvement was noted. Two and a half years after the last treatment session, the patient and treating physician noted no regression. A limitation of this therapy is that the combination approach makes it difficult to determine what individual contributions each treatment modality had on the final result. We have illustrated a successful multifaceted treatment regimen for hypertrophic scars and keloids using a combination approach.

Genetics of keloid scarring

Keloid scarring, also known as keloid disease (KD), is a common, abnormally raised fibroproliferative cutaneous lesion that can occur following even minor skin trauma. The aetiopathogenesis of KD has remained an enigma todate compounded by an ill-defined clinical management. There is strong evidence suggesting a genetic susceptibility in individuals affected by KD, including familial heritability, common occurrence in twins and high prevalence in certain ethnic populations. This review aims to address the genetic aspects of KD that have been described in present literature that include inheritance patterns, linkage studies, case-control association studies, whole genome gene expression microarray studies and gene pathways that were significant in KD. In addition to our clinical and scientific background in KD, we used search engines, Scopus, Scirus and PubMed, which searched for key terms covering various genetic aspects of KD. Additionally, genes reported in seven whole genome gene expression microarray studies were separately compared in detail. Our findings indicate a varied inheritance pattern in KD (predominantly autosomal dominant), linkage loci (chromosomes 2q23 and 7p11), several human leukocyte antigen (HLA) alleles (HLA-DRB1*15, HLA-DQA1*0104, DQ-B1*0501 and DQB1*0503), negative candidate gene case-control association studies and at least 25 dysregulated genes reported in multiple microarray studies. The major pathways reportedly proposed to be involved in KD include apoptosis, mitogen-activated protein kinase, transforming growth factor-beta, interleukin-6 and plasminogen activator inhibitor-1. In summary, involvement of more than one gene is likely to be responsible for susceptibility to KD. A better understanding of the genes involved in KD may potentially lead to the development of more effective diagnostic, therapeutic and prognostic measures.

Keloids: pathogenesis, clinical features, and management

Cutaneous wound healing is a complex response to skin injury. Deregulation of this process can lead to excessive scar formation, as seen in keloids. Keloids are common skin lesions that are difficult to treat and are associated with high recurrence rates despite the large number of available treatment options. With increased knowledge of the disease process and further scientific advancements, future approaches will hopefully improve keloid treatment. In this article, we review the epidemiology, genetic basis, etiology, clinical features, pathogenesis, and management of keloids.

Long-term outcome of intralesional injection of triamcinolone acetonide for the treatment of keloid scars in Asian patients

We studied the long-term outcome of injection of triamcinolone acetonide into keloid scars in Asian patients. Between 1985 and 2003, we treated 109 keloid scars in 94 patients by injecting 1 to 10?mg of triamcinolone acetonide depending on the size of the lesion at four week intervals. There was little morbidity. Thirty-one patients gave up treatment within 10 injections because of pain and lack of immediate improvement. Improvement in subjective symptoms was seen in 52 of the remaining 63 patients (82%). In objective symptoms, fair or better results were seen in 40 of 63 (63%), and good or better results in 25 of 63 (39%). The treatment method required 20-30 injections over three to five years. Although we did not achieve as good results as other authors, we think it was safer because we used a smaller dose of a steroid.

Dermatological lesions near the smallpox vaccination site after scab detachment

Lesions arising after scab detachment at the smallpox vaccination site have been described in the medical literature. We investigated reports of postscab lesions among US civilian volunteers vaccinated against smallpox from January through August 2003. We conducted enhanced surveillance, using a standard questionnaire, for reports of skin lesions appearing at or near the smallpox vaccination site after scab detachment. We identified 21 reports; 19 of the case patients responded to our questionnaire. The lesions (scab and/or fluid) of 7 case patients were tested for vaccinia virus by use of polymerase chain reaction and/or immunohistochemistry; all were found to be negative. We contacted 18 case patients 11 months after the initial lesion appearance; 10 (56%) of the 18 reported having another lesion appear after the initial postscab lesion had resolved. Lesions were heterogeneous in morphology, clinical appearance, and histology. The evidence from our case series and follow-up suggests that these lesions are self-limited, without significant clinical sequelae.