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

Keloids and hypertrophic scars are fibroproliferative disorders of the skin that are caused by abnormal healing of injured or irritated skin. It is possible that they are both manifestations of the same fibroproliferative skin disorder and just differ in terms of the intensity and duration of inflammation. These features may in turn be influenced by genetic, systemic, and local risk factors. Genetic factors may include single nucleotide polymorphisms, while systemic factors may include hypertension, pregnancy, hormones, and cytokines. The most important local factor is tension on the scar. Over the past 10 years, our understanding of the pathogenesis of keloids and hypertrophic scars has improved markedly. As a result, these previously intractable scars are now regarded as being treatable. There are many therapeutic options, including surgery, radiation, corticosteroids, 5-fluorouracil, cryotherapy, laser therapy, antiallergy agents, anti-inflammatory agents, bleaching creams and make-up therapies. However, at present, we believe that the following combination of three therapies most reliably achieves a complete cure: surgery, followed by radiation and the use of steroid tape/plaster. (J Nippon Med Sch 2016; 83: 46 53)

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%.

Keloids and intractable hypertrophic scars should be treated with dose protocols customized by site. Our results suggest that keloid and intractable hypertrophic scar sites with a high risk of recurrence should be treated with 20 Gy in 4 fractions over 4 days and that earlobe should be treated with 10 Gy in 2 fractions over 2 days.

A study was conducted to evaluate the early results of high-dose-rate superficial brachytherapy (HDR-SB) after keloidectomy. Between April 2008 and April 2009, 21 patients with 36 histologically confirmed keloids were treated with postoperative HDR-SB. The tube applicator was placed on the skin to match the area of the surgical wound, and a spacer 5 mm thick was placed between the skin and the applicator. A dose evaluation point was established below 2 mm from skin surface, and 20 Gy was delivered in 4 daily fractions to keloidectomy scars on the anterior chest wall, scapular region, lower jaw and suprapubic region. A dose of 15 Gy was delivered in 3 daily fractions to lesions in other areas. The median follow-up period was 18 months (range, 9 to 29 months). Therapeutic outcome was judged in terms of recurrence, control, or acute side effects. Three keloids (9.7%) in two patients showed local recurrence, with a median time to failure after HDR-SB of 12 months. All recurrences affected the anterior chest wall. Dysraphia occurred in only one patient with an anterior chest wall lesion. Excluding the cases of recurrence, acceptable cosmetic results were achieved. Our results indicate that HDR-SB is effective and safe for preventing recurrence of keloids.