Brachytherapy in the adjuvant management of keloid scars: literature review

Quantitative study on dose distribution of Freiburg flap for keloid high-dose-rate brachytherapy based on MatriXX

PURPOSE

To quantify the dose distribution effect of insufficient scattering conditions in keloid HDR brachytherapy with Freiburg fFlap (FF) applicator.

MATERIALS AND METHODS

A phantom composed of FF applicator, MatriXX and solid water slices was designed and scanned for treatment planning. Bolus with different thicknesses were covered to offer different scatter conditions. Planar dose distributions were measured by MatriXX. The maximum value (Max), average value (Avg) and γ passing rate (3 mm/3%) were evaluated by the software MyQA Platform.

RESULTS

The maximum and average doses measured by MatriXX were lower than the calculated values. The difference increased as field size decreased. The Max value, found at 0.86 cm level in the two tube case, was -20.0%, and the avg value was -11.9%. All the γ values were less than 95%. This difference gradually decreased with increasing bolus thickness and the γ values were significantly improved.

CONCLUSION

MatriXX could be used for dose verification of HDR brachytherapy with an FF applicator. When the FF applicator was applied for keloid, insufficient scattering conditions would cause an insufficient target dose. This difference could be reduced by covering the bolus with different thicknesses on the applicator. The smaller the field, the thicker the bolus required.

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

BACKGROUND

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

OBJECTIVE

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

METHODS

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

RESULTS

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

CONCLUSION

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

Current advances in the selection of adjuvant radiotherapy regimens for keloid

Keloid is a common benign skin tumor in the outpatient department, and patients are often accompanied by itching and pain. Since the pathogenesis is unknown, the effect of single method treatment is unsatisfactory, and therefore the recurrence rate is high. Therefore, comprehensive treatment is mostly used in clinical treatment. Adjuvant radiotherapy is currently one of the most effective treatments for keloid. After long-term clinical practice, brachytherapy and electron beam radiotherapy has increasingly become the gold standard of treatment, because brachytherapy provides more focused radiation treatment to focal tissue to significantly reduce recurrence rate, and better preserve normal tissue. With the development of new radiotherapy techniques, more options for the treatment of keloid. Currently, adjuvant radiotherapy has been widely recognized, but there is no consensus on the optimal protocol for adjuvant radiotherapy for keloids. This review provides a review of published treatment options and new radiotherapy techniques for adjuvant radiotherapy of keloids and gives a comprehensive evaluation for clinical treatment.

Non-Oncological Radiotherapy: A Review of Modern Approaches

Despite being usually delivered in oncological patients, radiotherapy can be used as a successful treatment for several non-malignant disorders. Even though this use of radiotherapy has been scarcely investigated since the 1950s, more recent interest has actually shed the light on this approach. Thus, the aim of this narrative review is to analyze the applications of non-oncological radiotherapy in different disorders. Key references were derived from a PubMed query. Hand searching and clinicaltrials.gov were also used. This review contains a narrative report and a critical discussion of non-oncological radiotherapy approaches. In conclusion, non-oncological radiotherapy is a safe and efficacious approach to treat several disorders that needs to be further investigated and used in clinical practice.

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

BACKGROUND

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

Efficacy of Surgical Excision and Adjuvant High-dose Rate Brachytherapy in Treatment of Keloid: Our Experience

Background

Keloids are dermal tumors that are due to increased production of collagen caused by abnormal and prolonged wound healing. The incidence of recurrence is extremely high if only conservative measures are used. This study was conducted to evaluate the feasibility and efficacy surgery and high dose rate brachytherapy as an adjuvant therapy for treatment of keloids.

Materials and Methods

50 patients with clinically diagnosed 71 keloids were treated with excision of keloid and post-operative high-dose rate brachytherapy were studied. Complete excision of the keloid till the healthy skin margin was excised. The wound were closed in 2 layers. Subcutaneous tissue closed using absorbable suture, over which a 6F flexible polyethylene tube was placed. High dose rate cobalt-60 brachytherapy was administered. Total of 15 Gy in divided dose, 5 Gy in 3 fractions were administered.

Results

50 patients with 71 keloids were studied. Out of the 50 patients, 12 were male (24%) and 38 were females (76%). Age of the patients ranged between 14 and 71 years. Recurrence rate was 2% with 2 keloids recurring at 5 months interval. 4 patients scored the results as unacceptable, remaining 45 patients rated their results as excellent during their follow up at 10 days, 3 months and 6 months.

Conclusion

Treatment of keloids in the plastic surgeon's practice even today is still challenging. Many therapies have been described, but recurrence rate is high with mono-therapy. Combination therapy especially surgical excision with postoperative radiotherapy is best in preventing recurrence.

Short-term efficacy of superficial X-ray treatment for infantile maxillofacial hemangioma

OBJECTIVES

This study aimed to explore the short-term clinical efficacy and factors influencing low-dose superficial X-ray for treating infantile maxillofacial hemangioma.

METHODS

Retrospective analysis was conducted on 161 cases of infants with maxillofacial hemangioma treated with superficial X-ray in the Laser Center of Dermatology Department of Sichuan Provincial People's Hospital from January 2015 to December 2017. Clinical efficacy was analyzed by comparing the photos before and after treatment. Patients were further divided into groups according to different genders, age at the start of treatment, preterm birth or low birth weight, hemangioma site, longest diameter of hemangioma, and type of hemangioma to analyze whether differences existed in clinical efficacy and therapeutic dose between different groups.

RESULTS

Twelve months after the end of treatment, the overall cure rate was 93.8%, and the significant efficiency was 97.5%. The clinical efficacy was related to the age of children at the beginning of treatment and the type of hemangioma (P<0.05). The clinical efficacy of children aged less than or equal to 12 months and superficial hemangioma group was better than that of children aged more than 12 months and deep subtype or mixed hemangioma group, respectively. Therapeutic doses associa-ted with hemangioma treatment with diameter, category, age (P<0.05), diameter greater than or equal to 4 cm hemangioma group, the mixed type or deep in the group, the children older than 12 months hemangioma group, respectively, the dia-meter is less than 4 cm hemangioma, superficial hemangioma group and age less than or equal to 12 months hemangioma total treatment group exposure dose is greater.

CONCLUSIONS

Low-dose superficial X-ray is safe and effective for the treatment of infantile maxillofacial hemangioma. Age and type of hemangioma at the time of treatment are the factors influencing therapeutic dose and clinical efficacy.

Strontium-90 brachytherapy following intralesional triamcinolone and 5-fluorouracil injections for keloid treatment: A randomized controlled trial

Background

Keloid disease is hard to fully eradicate. Recurrence and other unsatisfactory results were found in many patients. No current therapeutic modality has been determined to be most effective for treating keloid scars. Intralesional corticosteroid injections is most commonly recommended for primary management of small and young keloids as well as hypertrophic scars. However, it’s difficult for patients to adhere to long-term triamcinolone acetonide injection therapy because of the pain, inconvenience or complications including hormonal imbalance or irregular menstruation.

Objective

We aimed to determine whether and how Strontium-90 brachytherapy as an adjuvant radiation could affect keloid recurrence after intralesional triamcinolone and 5-fluorouracil injections.

Methods

We included keloid patients from March 2019 to September 2019 and randomly allocated them to two groups after 3 intralesional triamcinolone and 5-fluorouracil injections at 3 weeks interval. The experimental group received Strontium-90 brachytherapy at a total dose of 15-20Gy, while the control group didn’t receive any adjuvant treatment. We performed both Vancouver Scar Scale scoring and Color Doppler ultrasound examination to monitor and evaluate lesions regularly. A one-year follow-up was completed for each patient.

Results

31 patients who had 42 keloids in total were recruited. We found intralesional triamcinolone and 5-fluorouracil injections could effectively reduce the thickness and modify the hardness of small and young keloids. Strontium-90 brachytherapy reduced the one-year recurrence rate from 85.7 percent to 44.4 percent after 3 intralesional triamcinolone and 5-fluorouracil injections. The lesions’ thickness or elasticity was not affected by Strontium-90 brachytherapy.

Conclusion

Strontium-90 brachytherapy as an adjuvant radiation could effectively reduce small sized keloids recurrence after intralesional triamcinolone and 5-fluorouracil injections. It worked by enhancing the lesions’ stability post-injection.

Trial registration

The clinical trial registration number: ChiCTR2000030141.

Name of trial registry: Chinese Clinical Trial Registry (http://www.chictr.org.cn/)

Pilot Study of External Beam Radiotherapy for Recurrent Unremitting Tracheal Stenosis

OBJECTIVE

Tracheal stenosis can have a variety of presentations, severities, causes, and be a difficult condition to treat. Some patients demonstrate recurrent stenosis after multiple endoscopic treatments and are either poor candidates for open procedures or do not desire open surgery. We sought to evaluate low-dose postoperative external beam radiotherapy (EBRT) as a novel therapy for patients with recurrent tracheal stenosis refractory to endoscopic therapies.

METHOD

We performed a retrospective review of patients with recurrent tracheal stenosis who underwent EBRT in addition to endoscopic dilation. We compared the number of endoscopic procedures required in the 6 months before EBRT to the number required in the 6 months after EBRT.

RESULTS

Six patients met criteria for inclusion in our study. The cause of stenosis was variable among the study population. In the 6 months leading up to EBRT, patients underwent an average 6.2 endoscopic procedures. This dropped to an average 1.9 procedures in the 6 months following EBRT (P < .001).

CONCLUSION

Herein, we show that low-dose postoperative external beam radiotherapy (EBRT), a novel therapy for patients with recurrent tracheal stenosis refractory to endoscopic therapies, is effective in decreasing the frequency of endoscopic dilations.

LEVEL OF EVIDENCE

4.

Identification of differentially expressed circular RNAs in keloid and normal skin tissue by high-throughput sequencing

Keloid is a kind of pathological skin scar with unclear molecular pathology. Circular RNAs (circRNAs) are involved in the occurrence and development of many diseases; however, their relationship with keloid is not well understood. To investigate the involvement of dysregulated circRNAs in keloid. Thirty-seven keloids and 37 normal skin tissues were collected, and the changes of circRNAs, microRNAs (miRNAs) and mRNAs in 3 keloids and 3 normal samples by high-throughput sequencing were detected first. Based on the circRNA-miRNA-mRNA interaction network construction, gene ontology and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis combining several signaling pathways associated with keloid formation and progression, the circRNAs required further verification were screened out. The expression levels of the selected circRNAs were verified in 37 keloids and 37 normal skin tissues using quantitative real-time polymerase chain reaction (QPCR). The interaction of candidate circRNA and its predicted binding miRNA was tested by dual-luciferase reporter gene experiment. Compared with normal controls, there was an average of 120 and 12 circRNAs, 44 and 63 miRNAs, 656 and 156 mRNAs were upregulated and downregulated, respectively, in keloids. According to the analysis of bioinformation, six circRNAs were picked out. The QPCR validation results of two upregulated circRNAs (hsa_circ_0001320 and circCOL5A1) were consistent with previous sequencing results. The interaction between hsa_circ_0001320 and miR-574-5p was confirmed. This study makes it clear that the abnormal expression of circRNAs may be related to the pathological process of keloid.

Keloids: A Review of Etiology, Prevention, and Treatment

Keloids are abnormal scars that cause significant emotional and physical distress in patients when inadequately treated. Keloid formation is theorized to occur as a result of an imbalance between an increased synthesis of collagen and extracellular matrix and decreased degradation of these products. Inflammatory mediators- namely, transforming growth factor beta-have been proposed to influence the dysregulation of collagen remodeling in the scar healing process. Though limited, current knowledge of keloid pathophysiology has guided clinicians to explore novel therapies for keloid prevention and treatment. In addition to conducting research refining the use of common therapies, such as steroids and radiation, clinicians have evaluated the potential of anti-inflammatory and chemotherapeutic molecules to suppress keloid recurrence. Procedural focused therapies, such as cryotherapy and lasers, have also found a role in reducing keloid symptomatology. The purpose of this report is to examine the current literature and review the mechanisms of action, efficacy, and side effects of different keloid therapies. Despite the growing literature investigating reliable methods for keloid management, there are no standardized guidelines or treatment protocols supported by academic governing bodies. Stronger evidence with high-fidelity randomized clinical trials will be needed to determine the optimal therapy regimens for keloids.

Surgical Excision of Keloids Followed by In-office Superficial Radiation Therapy: Prospective Study Examining Clinical Outcomes

Background:

Keloids are benign proliferative scars that often occur among individuals of color, and are thought to be the result of excessive collagen deposition that occurs after injury to the skin. The treatment of these scars is difficult with often poor outcomes. This study aimed to evaluate the effectiveness of surgical excision followed by in-office superficial radiation therapy (SRT) as a method to improve keloid remission.

Methods:

Participants for this study were recruited from June 2016 through February 2017 with 48 subjects enrolled and completed this study. All keloids were surgically resected and participants received 3 consecutive days of a customized dose of SRT, with a maximum cumulative dosage of 18 Gy. Patients were followed over the course of 12 months to monitor outcomes.

Results:

In this cohort, we found 39 (81%) to have achieved successful remission with 9 (19%) being classified as refractory. There were no adverse effects or medical complications reported as a part of this study.

Conclusion:

Study outcomes support the clinical benefits of surgical excision followed by SRT as a practical and efficient treatment for keloids.

Surgical excision and postoperative radiotherapy for keloids

Keloids can be treated in a number of ways, including by surgery. Multiple studies now show that while surgical monotherapy associates with extremely high rates of recurrence (50%-80%), postoperative radiotherapy can significantly reduce these recurrence rates. Ongoing improvements in radiation technology have further increased the safety and efficacy of this combination protocol. Of the various radiotherapies that have been used in this setting, electron beam (β-ray) irradiation is currently the best due to its excellent dose distribution and safety. The maximal biologically effective dose (BED) for keloids is 30 Gy (using an estimated α / β ratio of 10); increasing the dose has no further benefits and elevates side effects. Over the last two decades, we have modified and then fine-tuned our radiotherapy protocol for keloid excision wounds. Thus, our early protocol was used for all body sites and consisted of 15 Gy/3 fr/3 days. We then customised the radiotherapy protocol so that body sites that are highly prone to recurrence (e.g. the anterior chest) receive higher doses while low recurrence sites like the earlobe receive a much smaller dose. More recently, we tweaked this body site-customised protocol so that fewer fractions are employed. Therefore, we currently apply 18 Gy/3 fr/3 days to high-recurrence sites, 8 Gy/1 fr/1 day to earlobes and 15 Gy/2 fr/2 days to other body sites. These radiotherapy protocol changes were accompanied by the evolution of body site-customised surgical approaches. As a result of these developments, our overall keloid recurrence rate is now below 10%.

Brachytherapy in the adjuvant management of keloid scars: literature review

INTRODUCTION

Radiation therapy is a well-recognised modality for the adjuvant treatment of keloid scars. It can be conventionally delivered as external beam using a large apparatus at a distance from the lesion or as brachytherapy with specialised equipment to enable the delivery of treatment in the immediate vicinity of the keloidal tissue.

METHODS

An English literature review was performed with keywords 'brachytherapy' and 'keloid' using the databases PubMed, Embase and Web of Science from their individual dates of inception until June 2017. Studies pertinent to the field are presented in a chronological manner to depict the evolution of different brachytherapy strategies over the last decades. We also discuss considerations relating to the risk of secondary carcinogenesis, which are relevant to shared decision-making in the clinical setting.

DISCUSSION

Low dose rate interstitial brachytherapy was first introduced in the English literature in 1976 and currently appears to have been superseded by more modern approaches, including high dose rate interstitial brachytherapy. This modality compares favourably to more traditional modes of radiotherapy in terms of recurrence as well as rates of symptomatic relief from keloidal symptoms. Superficial brachytherapy was introduced more recently in the relevant literature and appears to be associated with favourable therapeutic outcomes compared to external beam radiation therapy.

CONCLUSION

Brachytherapy is a valid modality of radiotherapy for the adjuvant treatment of keloid scars, with high dose rate interstitial and surface regimens gaining in popularity over recent years. Further research needs to focus on randomised controlled trials to further establish the role of different radiotherapy modalities in keloid scar management.