Algorithm of chest wall keloid treatment

Keloids are common in the Asian population. Multiple or huge keloids can appear on the chest wall because of its tendency to develop acne, sebaceous cyst, etc. It is difficult to find an ideal treatment for keloids in this area due to the limit of local soft tissues and higher recurrence rate. This study aims at establishing an individualized protocol that could be easily applied according to the size and number of chest wall keloids.A total of 445 patients received various methods (4 protocols) of treatment in our department from September 2006 to September 2012 according to the size and number of their chest wall keloids. All of the patients received adjuvant radiotherapy in our hospital. Patient and Observer Scar Assessment Scale (POSAS) was used to assess the treatment effect by both doctors and patients. With mean follow-up time of 13 months (range: 6-18 months), 362 patients participated in the assessment of POSAS with doctors.Both the doctors and the patients themselves used POSAS to evaluate the treatment effect. The recurrence rate was 0.83%. There was an obvious significant difference (P < 0.001) between the before-surgery score and the after-surgery score from both doctors and patients, indicating that both doctors and patients were satisfied with the treatment effect.Our preliminary clinical result indicates that good clinical results could be achieved by choosing the proper method in this algorithm for Chinese patients with chest wall keloids. This algorithm could play a guiding role for surgeons when dealing with chest wall keloid treatment.

Application of mitomycin-C for head and neck keloids

Keloids of the head and neck are a relatively common entity in darker-skinned races, occurring in 5%-15% of skin wounds. Keloids are fibrotic lesions that are a result of an abnormal wound-healing process that lacks control of the mechanisms that regulate tissue repair and regeneration. The proliferation of normal tissue-healing processes results in scarring that enlarges well beyond the original wound margins.

Many treatment modalities for keloids have been tried with variable amounts of success. Surgical excision, compressive therapy, silicon dressings, corticosteroid injections, radiation, cryotherapy, interferon therapy, and laser therapy have all been used alone or in combination. Despite this wide range of available treatments, recurrence rates typically remain in the 50%-70% range.

In this study, we present our results in a series of 10 patients who were treated with surgical excision of head and neck keloids and the application of topical mitomycin-C. Mitomycin-C is a chemotherapeutic agent that inhibits DNA synthesis and fibroblast proliferation. It has been used in ophthalmologic procedures and airway surgery to decrease scar formation. In these 10 patients, we combined surgical excision of keloids with the application of topical mitomycin-C. The patients were then followed postoperatively for recurrence (range, 7-14 months). We have found topical application of mitomycin-C to be an effective therapy for prevention of keloid recurrence in the head and neck, with a success rate of 90% as reported in this series.

Admixture mapping identifies a locus at 15q21.2-22.3 associated with keloid formation in African Americans

Keloids are benign dermal tumors that occur ~20 times more often in African versus Caucasian descent individuals. While most keloids occur sporadically, a genetic predisposition is supported by both familial aggregation of some keloids and the large differences in risk among populations. Yet, no well-established genetic risk factors for keloids have been identified. In this study, we conducted admixture mapping and whole-exome association using 478 African Americans (AAs) samples (122 cases, 356 controls) with exome genotyping data to identify regions where local ancestry associated with keloid risk. Logistic regression was used to evaluate associations under admixture peaks. A significant mapping peak was observed on chr15q21.2-22.3. This peak included NEDD4, a gene previously implicated in a keloid genome-wide association study (GWAS) of Japanese individuals later validated in a Chinese cohort. While we observed modest evidence for association with NEDD4, a more significant association was observed at (myosin 1E) MYO1E. A genome scan not including the 15q21-22 region also identified associations at MYO7A (rs35641839, odds ratio [OR] = 4.71, 95% confidence interval [CI] 2.38-9.32, p = 8.34 × 10(-6)) at 11q13.5. The identification of SNPs in two myosin genes strongly associated with keloid formation suggests that an altered cytoskeleton contributes to the enhanced migratory and invasive properties of keloid fibroblasts. Our findings support the admixture mapping approach for the study of keloid risk, and indicate potentially common genetic elements on chr15q21.2-22.3 in causation of keloids in AAs, Japanese, and Chinese populations.

Multicenter Study of Wound Healing in Neurofibromatosis and Neurofibroma

Based on clinical experience, the senior author has become convinced that wounds produced to correct the deformities of patients with neurofibromatosis (NF-1) have produced remarkably good scars, the interesting feature being that progression to keloid or hypertrophic scar is rare. The other point noted was that this situation did not change, no matter the patient's race or skin color. There have been few reports describing or discussing this hypothesis. The purpose of this study was to investigate whether wounds produced in the patients with NF-1 produce keloid or hypertrophic scars. The patients with solitary neurofibroma were also included in this study; these were compared with the NF-1 group. This was conducted as a multicenter study. Patients with neurofibromatosis/solitary neurofibroma, who were operated on from 1990 to 2000, were evaluated by reviewing their medical charts and photographs retrospectively. The patients were treated in centers from five different countries. The analysis was undertaken based on the following points: 1) age and sex at surgery; 2) race of the patients; 3) past and family histories of hypertrophic scar and keloid; 4) surgical site(s); 5) diagnosis, NF1 or solitary neurofibroma; 6) surgical complications; 7) number of reoperations to manage the complications; 8) adjuvant therapy for the tumor; 9) depth of the tumors; and 10) incidence of malignant degeneration. A total of 101 cases with neurofibromatosis or solitary neurofibroma was analyzed. The age at surgery ranged from 1 year 6 months to 74 years; sex ratio was 47 males and 54 females. The racial distribution of the patients was 13 white, 13 black, 3 Hispanic, and 58 Asian. There was no past or family history of hypertrophic scar or keloid. The surgical sites were head and neck in 70 cases, trunk in 20 cases, upper extremities in 22 cases, and lower extremities in 20 cases. The clinical diagnosis was NF-1 in 57 cases, solitary neurofibroma in 35 cases, plexiform neurofibroma in four cases, and no distinct clinical diagnosis in five cases. There were no other types of neurofibromatosis. Hematoma and white wide scar were the main postoperative complications found in six cases of NF-1. Infection was also noted in four cases. However, no patient developed hypertrophic scar or keloid in the neurofibromatosis group, whereas two cases showed hypertrophic scar in the solitary neurofibroma group. The outcome showed that the patients with NF-1 and plexiform neurofibroma, no matter the racial group, produce good scars without keloid or hypertrophic changes, whereas solitary neurofibroma has a potential to cause hypertrophic scar.

[Location of predisposing gene for one Han Chinese keloid pedigree]

OBJECTIVE

To locate the locus of predisposing gene for Han Chinese keloid pedigree.

METHODS

One large Chinese keloid pedigree with affected family members in five generations was investigated and confirmed. Venous blood samples from 32 members in this family were collected and extracted genomic DNA. Fas gene was assumed as one of the candidate genes resulting in keloids in this pedigree. Four markers, D10S1687, D10S1765, D10S1735 and D10S1562 next to the all known genes relating with apoptosis or tumorigenesis in the 10 Mbp region around Fas gene on chromosomes 10q23.31 were selected as microsatellite markers. Subsequently, these markers were amplified by PCR, and all PCR products were genotyped and the linkage analyses were performed.

RESULTS

After linkage analyses, D10S1765LOD(ZMAX) was 1.74, D10S1735LOD(ZMAX) was 1.51. These findings supported the linkage. D10S1562LOD(ZMAX) was 0.59, which did not exclude the linkage. All LODs for D10S1562 were less than - 2, at 0 = 0.0 - 0.10, which excluded the linkage.

CONCLUSIONS

This study provides the first genetic evidence that the predisposing gene for this Han Chinese keloid pedigree may be mapped to the region about 1 Mbp on chromosomes 10q23.31, between marker D10S1765 and D10S1735.

[Preliminary linkage analysis and mapping of keloid susceptibility locus in a Chinese pedigree]

OBJECTIVE

To investigate the linkage between the susceptibility locus to keloid and two loci, 15q22.31-q23 and 18q21.1, the authors performed linkage analysis of a pedigree.

METHODS

A five-generation Han Chinese family of keloid was investigated and confirmed. Venous blood samples of 32 members in this family were collected for PCR and genetic analysis. Seven microsatellite markers spanning the critical regions on chromosomes 15q22.31-q23 and 18q21.1 were genotyped, and the DNA extracted from each sample was amplified for these markers. The PCR products of them were scanned at ABI PRISM 310 Genetic Analyzer, the eligible genotyping data were used for linkage analysis. The two-point LOD scores were calculated by MLINK program of Linkage5.11.

RESULTS

Among the 7 markers, the two-point LOD scores of 5 ones (D15S108, D15S216, D15S534, D18S363, D18S846) were less than -2 at theta = 0, they were excluded the linkage to the disease locus; but the scores of other two (D18S460, D18S467) were either more than 1 at theta = 0.05 & 0.10 and D18S460 was 2.201, which showed linkage to the disease locus in some extent. Conclusions This study firstly reported and provided some evidence that keloid susceptibility locus of Chinese family maybe on chromosome 18q21.1, SMAD and PIAS2 may be the possible genes.

[p53 gene codon 72 polymorphism and susceptibility to keloid in Chinese population]

OBJECTIVE

To investigate the relationship between p53 codon 72 polymorphism and susceptibility to keloid.

METHODS

The p53 genotypes were detected by polymerase chain reaction-reverse dot blot (PCR-RDB) and DNA direct sequencing among 15 healthy controls and 15 patients with keloid.

RESULTS

The frequency of the Pro allele (P = 0.035) and Pro/Pro genotype (P = 0.030) in patients was significantly higher than that in the controls. There was no significant difference in the frequency of Pro/Arg and Arg/Arg genotypes between patients and controls.

CONCLUSION

The p53 gene codon 72 polymorphism may play a role in susceptibility to keloid.

Description of site-specific morphology of keloid phenotypes in an Afrocaribbean population

By examining the keloid scars of 211 Afrocaribbean patients presenting to the Plastic Surgery unit in Kingston, Jamaica, we have described site-specific morphologies of scarring; keloid disease is not a homogenous biological entity. All cases conformed to clinical criteria for diagnosis of keloid scarring: 369 keloid scars were present in 137 females (2-83 years; mean 29.6 years; SD+/-14.9 years) and 74 males (5-90 years, mean 29.5 years; SD+/-15.0 years). Morphologies were specific to each anatomical site: trunk scars (n=45,12.1%) were geometrically shaped with clear margins or irregular in outline, surface and margin; back single scars were well-demarcated botryoid but multiple scars were butterfly-shaped, spheroidal and irregular; chest scars (n=72,20.1%) were butterfly or nonbutterfly shaped found most commonly in the midsternal line; upper limb scars (n=57,15.3%) mostly in the deltoid region (propeller shaped) or elsewhere nodular, linear to irregular; ear (n=85,23%) commonest site being the lobe, having reniform to bulbous shape; face and neck (n=60,16.2%) scars were firm nodular to hard; posterior auricular scars were either horizontal and oblong-shaped or vertical and reniform in outline; scalp scars (n=11,2.8%) were commonest in the occipital area varying from small papules to large plaques; lower limb scars (n=39,10.5%) varied from propeller, butterfly, petalloid to dum-bell-shaped. Three plantar and eight pubic keloids were rare findings. Recognition of different morphological phenotypes is necessary in understanding genotypic predisposition and aiding diagnosis, treatment and prognosis of keloid scars.

A study of the spectrum of skin disease occurring in a black population in south-east London

We recorded the diagnosis made in 461 black patients (187 children and 274 adults) attending a dermatology clinic between January and March 1996. In the childhood population, atopic eczema and tinea capitis were the most frequent dermatoses, comprising 63% of diagnoses recorded. In the adult population, acne and acne keloidalis nuchae were seen most frequently. Other conditions observed commonly were eczema, psoriasis, keloid scarring, pityriasis versicolor and postinflammatory changes. Our study demonstrates a wide spectrum of skin disease and includes disorders more common in black skin, disorders unique to black skin, those which present a greater cosmetic disability, and normal findings which have been mistaken for pathological disease.

Photorefractive keratectomy in African Americans including those with known dermatologic keloid formation

PURPOSE

To report the outcome of photorefractive keratectomy in African Americans, including those with a known history of dermatologic keloid formation.

METHODS

A retrospective analysis of African American patients who had photorefractive keratectomy at either of our institutions was undertaken to identify all patients who were at least 3 months status-post refractive surgery. The presence or absence of a history of keloid formation, as well as preoperative and postoperative measurements of uncorrected visual acuity, best-corrected visual acuity, manifest refraction, and the presence and magnitude of any postoperative corneal haze were analyzed.

RESULTS

Twelve patients (19 eyes) met the inclusion criteria and three of these patients (six eyes) had a history of keloid formation. Mean uncorrected visual acuity +/- SD for the entire study group improved from 20/369 +/- 20/270 preoperatively to 20/19.4 +/- 20/7.1 postoperatively (average follow-up, 13.8 months). All eyes had postoperative uncorrected visual acuity of 20/40 or better; 14 (74%) achieved 20/20 or better. Mean best spectacle corrected visual acuity went from 20/14.8 +/- 20/2.8 preoperatively to 20/15.5 +/- 20/3.2 postoperatively (not statistically significant). Mean manifest spherical equivalent was -4.9 +/- 3.4 diopters preoperatively and +0.03 +/- 0.55 diopters postoperatively. Eight eyes (42%) had trace to 1+ corneal haze following photorefractive surgery. A comparison of postoperative uncorrected and best-corrected visual acuities of known keloid formers with nonkeloid formers revealed no significant statistical difference.

CONCLUSIONS

African Americans may have excellent visual outcomes following photorefractive keratectomy. History of keloid formation does not appear to have an adverse effect on the outcome. These results question whether known dermatologic keloid formation should be a contraindication to photorefractive keratectomy.

Keloid formation from levonorgestrel implant (Norplant System) insertion

It is possible that women of certain ethnic backgrounds, specifically those more prone to keloid formation, are also more prone to the insertion site complications of levonorgesterel implants. Failure to recognize the potential for this complication and to provide adequate guidance to the patient could result in unwarranted cost and complications. It is possible that intralesional steroid injection at the first sign of a local reaction will minimize the formation of a keloid; however, specific research will need to be done before a change in practice can be recommended.

Altered cytokine production in black patients with keloids

The treatment of keloids in black patients remains a medical dilemma. Previous studies have focused on primary alterations in the metabolism of fibroblasts as the key in the etiology of this condition. Yet alterations in the production of various cytokines which may alter fibroblast responses secondarily have received little attention. Twelve black patients with clinical and histological diagnosis of keloids and eight black control volunteers were studied. Peripheral blood mononuclear-cell (PBMC) fractions from both groups were assayed for production of interleukin-1 (IL-1), interleukin-2 (IL-2), interleukin-6 (IL-6), alpha-interferon (IFN-alpha), beta-interferon (IFN-beta), gamma-interferon (IFN-gamma), tumor necrosis factor-alpha (TNF-alpha), and tumor necrosis factor-beta (TNF-beta). The production of IFN-alpha, IFN-gamma, and TNF-beta were markedly depressed in keloid patients compared to normal controls. However, IL-1 and IL-2 production was not significantly different between the two groups. In contradistinction, keloid patients produce greater amounts of IL-6, TNF-alpha, and IFN-beta. Altered levels of immunoregulatory cytokines may play a significant role in the net increase in collagen which characterizes keloid formation.

On the nature of keloid and hypertrophic scars

Clinical observations make it possible in most cases to differentiate between keloid and hypertrophic scars. This suggests that different biological factors are involved in the two groups. In clinical practice in the United Kingdom most keloid scars occur spontaneously. In black-skinned people and orientals the factors of keloid and hypertrophic scars may overlap and potentiate each other.

Keloids

Keloids are benign fibrous growths that result from an abnormal connective tissue response in certain predisposed individuals. Blacks form keloids more often than whites; however, the reason for this racial difference is not known. Trauma, foreign-body reactions, infections, and endocrine dysfunction have all been proposed as precipitating factors. Keloids are found most commonly on the ear lobes, shoulders, upper back, and midchest. They extend past the area of trauma and once present tend to remain stable. Although sometimes pruritic, painful, or tender, they are usually asymptomatic. Histologically, keloids are characterized by thick collagen bundles, abundant mucinous ground substance, few fibroblasts, and few if any foreign-body reactions. Although there have been many therapeutic modalities, most have had limited success. The most commonly used therapeutic approach is a combination of cryotherapy, intralesional steroid injections, surgical excision, and pressure devices.