reconstructive

RECONSTRUCTIVE Outcomes of Surgical Excision with Pressure Therapy Using Magnets and Identification of Risk Factors for Recurrent Keloids Tae Hwan Park, M.D. Sang Won Seo, M.D. June-Kyu Kim, M.D. Choong Hyun Chang, M.D., Ph.D. Seoul, Korea

Background: In a previous study, the authors described an adjuvant pressure therapy using magnets for the management of ear keloids. The purpose of the present study was to build on this previous study by expanding the cohort of patients, evaluating treatment outcomes by means of a prospective study and identifying risk factors for recurrent ear keloids. Methods: The authors treated 1436 ear keloids in 883 patients with surgical excision followed by pressure therapy using magnets at Kangbuk Samsung Hospital over the 7.25-year period from December of 2002 to February of 2010. Six hundred eighteen of 883 patients (70 percent) had histories of treatment failure at other hospitals. The follow-up period was 18 months. Therapeutic outcomes were evaluated as recurrence or nonrecurrence. Comparisons between the two groups (recurrence versus nonrecurrence) were made using Mann-Whitney tests for continuous variables, the chi-square test and the Fisher’s exact test for categorical variables, and multivariate logistic regression for investigating associations between possible risk factors and keloid recurrence. Results: The overall recurrence-free rate was 89.4 percent after a follow-up period of 18 months. Keloid recurrence was significantly associated with the presence of prior treatment history, keloid low growth rate, and high patient body mass index. Conclusions: The authors’ protocol results in excellent outcomes in cases of ear keloids. Patients with prior treatment history, low growth rates of keloids because of longer duration of disease, and high body mass index should be monitored closely for signs of recurrence and managed cautiously during ear keloid treatment. (Plast. Reconstr. Surg. 128: 431, 2011.) CLINICAL QUESTION/LEVEL OF EVIDENCE: Risk, III.

K

eloids can appear months or even years after the primary injury and tend not to regress.1 Keloids are often resistant to treatment and have high recurrence rates.2 Earlobes are common sites for keloids following ear piercing, with an incidence of approximately 2.5 percent.3 Given the consequences of ear keloids, including cosmetic deformity and psychological trauma, understanding of risk factors for recurrence is imperative to provide optimal treatment.4 Although some possible risk factors for overall keloid recurrence have been described,5 most reports in the literaFrom the Department of Plastic and Reconstructive Surgery, Kangbuk Samsung Hospital, Sungkyunkwan University School of Medicine. Received for publication December 13, 2010; accepted February 25, 2011. Copyright ©2011 by the American Society of Plastic Surgeons DOI: 10.1097/PRS.0b013e31821e7006

ture suffer from small numbers of patients and inadequate follow-up.6 Numerous treatment methods have been proposed for earlobe keloids, suggesting that no single method has surfaced as the accepted standard.7 Pressure therapy has evolved as an important adjuvant treatment for ear keloids, and numerous pressure earrings have been introduced.8 –13 Although clinical studies describing it are scarce, adjuvant pressure therapy is widely used in the treatment of ear keloids, and recurrence-free rates generally exceed 60 percent.14,15 In a previous study, we described an adjuvant pressure therapy that included the use of magnets for the management of ear keloids.12 The current report expands on those experiments by

Disclosure: The authors have no financial interest to declare in relation to the content of this article.

www.PRSJournal.com

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Plastic and Reconstructive Surgery • August 2011 investigating keloid recurrence rates in a prospective study analyzing the outcomes of this treatment protocol. We conclude that surgical excision combined with pressure therapy using magnets improves outcomes over conventional approaches for keloid treatment.

PATIENTS AND METHODS Inclusion and Exclusion Criteria and Study Design Patients were treated with surgical excision combined with magnetic disk pressure therapy over a period of 7.25 years from December of 2002 to February of 2010 at our hospital. Patients with ear keloids who presented to the outpatient clinic were included in the study according to the following criteria: (1) the scar was elevated and extended beyond the dimensions of the initiating injury site or lesion; (2) the patients were older than 8 years; (3) surgical excision with primary closure was scheduled; and (4) patients did not undergo additional ear piercing during treatment before final outcome measurement. Patients were excluded from the study if they were unavailable for follow-up, and all patients who were included agreed to comply with the treatment protocol. Patients were also excluded from the study if they received additional adjuvant therapy during treatment or histologic confirmation was not obtained. All included patients consented to the requirement for final follow-up after 18 months. We analyzed data including patient age, sex, age of keloids before treatment, anatomical locations, previous treatment history and modality, recurrence, and clinical photographs. Surgical Technique and Postoperative Care All procedures were performed under local anesthesia. We excised lesions as completely as possible, and bleeding was controlled by step-bystep bipolar coagulation. We closed wounds with appropriate approximation using nylon 5-0 interrupted sutures. We inserted Silastic drains if the excised mass was large and created dead space. We also applied compressive wound dressing to prevent dehiscence caused by hematoma of the surgical wound. All keloids were sent for histologic examination to confirm clinical diagnoses. The drains were removed on postoperative day 1, if present, and stitches were removed on postoperative days 14 to 21. Pain was controlled by administration of nonsteroidal antiinflammatory drugs.

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Adjuvant Pressure Therapy Using Magnets Patients were instructed to use the magnets for approximately 12 hours per day for 6 months until the therapy was completed. During the adjuvant pressure therapy, patients were seen frequently for follow-up for recurrence and evaluation of the success of the therapy (Fig. 1). Our protocol included five cycles of application repeated throughout the day. Each cycle was composed of 2 hours of magnet application followed by a half hour of relief. The applied pressure was 35 mmHg, which was estimated using a digital manometer. Despite a strict protocol, the discomfort experienced when pressure was applied to the ear keloids was not prominent. Even in postauricular lesions where application of magnets was not feasible, we used conventional magnets without any customized pressure device. Follow-Up and Outcome Assessment In all patients, a follow-up period of 18 months was required. Treatment outcome was recorded as recurrence or nonrecurrence. Complications were also recorded. Nonrecurrence was defined as a scar without signs of elevation and extension, although slight scarring or redness could be present (Fig. 2). Recurrence was defined as any elevation of the scar or extension beyond the original surgical field. Statistical Analysis All statistical analyses were conducted using SPSS version 17.0 (SPSS, Inc., Chicago, Ill.). Our

Fig. 1. Versatility of magnets.

Volume 128, Number 2 • Ear Keloid

Fig. 2. (Above, left) Helix keloid, (above, right) postoperative view (18 months after surgical excision with adjuvant pressure therapy using magnets), and (below) gross specimen are shown.

data were not normally distributed; consequently, nonparametric tests were used. Descriptive statistics are presented as medians with interquartile ranges or as numbers and percentages. To compare medians of continuous variables (i.e., patient age, keloid size, maximal keloid size, age of keloids, keloid growth rate, and patient body mass index), Mann-Whitney tests were used. Chi-square tests were used to assess any differences between categorical variables (i.e., sex, anatomical location of keloid, previous treatment history, cause, and number of ear keloids). Fisher’s exact tests were used in place of chi-square tests when expected cell values were less than or equal to 5. Multivariate logistic regression analysis was then applied, incorporating possible risk factors that had been linked to recurrence in univariate analysis for the purpose of determining which, if any, factors in-

teracted with each other in keloid recurrence. Odds ratios and associated 95 percent confidence intervals were calculated for each of the independent variables in the multivariate logistic regression models. Two-tailed values of p ⬍ 0.05 were considered statistically significant.

RESULTS Patient Characteristics Sex, Age, and Anatomical Locations Of the 883 patients, 827 (93.7 percent) were women and 56 (6.3 percent) were men (Table 1). The average age was 24 years (range, 21 to 27 years), and patients aged 21 to 30 years showed the highest prevalence. The locations of ear keloids in order of frequency were the lobule [635 patients (71.9 percent)] (Figs. 3 and 4), helix [193 patients

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Plastic and Reconstructive Surgery • August 2011 Table 1. Baseline Patient Characteristics* Characteristic Total no. of patients Continuous variables Age, years Total size, cm Maximal diameter, cm† Age of keloids, years Growth rate, cm/yr BMI, kg/m2 Categorical variables Sex Female Male Anatomical locations Lobule Helix Both lobule and helix Other portions Previous treatment history No Yes Surgical excision Steroid injection Excision plus steroid injection Excision plus pressure therapy Other treatments Cause Ear piercing Laceration Surgery Infection Idiopathic No. of ear keloids One Two Three Four Six

Value 883 24.00 (21.00–27.00) 2.00 (1.30–3.00) 1.50 (1.00–2.00) 3.00 (2.00–5.00) 0.50 (0.33–1.00) 21.00 (19.00–22.00) 827 (93.7) 56 (6.3) 635 (71.6) 193 (21.9) 41 (4.8) 14 (1.6) 265 (30.0) 618 (70.0) 155 (17.6) 333 (37.7) 32 (3.6) 78 (8.8) 20 (2.3)

Fig. 3. Unilateral earlobe keloid.

855 (96.8) 11 (1.2) 10 (1.1) 3 (0.3) 4 (0.5) 435 (49.3) 366 (41.4) 61 (6.9) 20 (2.3) 1 (0.1)

*Values are expressed as median (interquartile range) for continuous variables and number (percentage) for categorical variables. †Maximal diameter means the maximal diameter of the largest lesion of a single patient.

(21.9 percent)] (Fig. 5), both lobule and helix [41 patients (4.6 percent)] (Fig. 6), and other areas [14 patients (1.6 percent)] (Figs. 7 and 8). Age of Keloids before Treatment (Duration of Presence), Size of Keloid before Treatment, and Keloid Growth Rate The average time interval between keloid formation (or prior complete treatment) and time of treatment was 3 years (range, 2 to 5 years). The average pretreatment total size of lesions was 2.0 cm (range, 1.3 to 3.0 cm), and average diameter of the largest lesion of a single patient was 1.5 cm (range, 1.0 to 2.0 cm). The growth rate was calculated by dividing the maximal diameter of the largest lesion of a single patient with its duration of presence (age of keloids before treatment). The average growth rate was 0.50 cm/year (range, 0.33 to 1.00 cm/year). Previous Treatment History The number of patients treated for a primary ear keloid was 265 (30 percent), and 618 patients

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Fig. 4. Bilateral earlobe keloids.

(70 percent) were treated for a recurrent ear keloid that failed to respond to other treatments. These other treatments included single therapies such as prior excision surgery [155 patients (17.6 percent)]; prior intralesional steroid injection [333 patients (37.7 percent)]; and prior other single therapy alone including laser therapy, acupuncture, cryotherapy, or Botox injection [12 pa-


Fig. 5. Bilateral helix keloids.

tients (0.3 percent)]. Of these 12 patients, eight had laser therapy (0.9 percent), three had prior acupuncture (0.3 percent), and one had prior cryotherapy (0.1 percent). The other therapies also included combination treatments such as combination of excision with pressure therapy [78 patients (8.8 percent)], combination of excision with intralesional steroid injection [32 patients (3.6 percent)], and other combination of therapies [eight patients (0.9 percent)]. None of the patients was previously treated with magnets. Outcome Assessment All patients completed the treatment protocol, with a follow-up interval of 18 months (Ta-

ble 2). Of these patients, 89.4 percent had successful treatment of their ear keloids, whereas 10.6 percent had recurrences. The postoperative course was uneventful, with the exception of three patients (0.3 percent) (Fig. 9) who presented with tissue necrosis after magnet application and eight patients (0.9 percent) who had a minor dehiscence caused by hematoma of the surgical wound. Patient demographics and keloid characteristics were evaluated as possible risk factors for keloid recurrence. As shown in Table 2, events of keloid recurrence were associated with a significantly lower degree of keloid growth rate compared with events of nonrecurrent cases (0.5

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Plastic and Reconstructive Surgery • August 2011 patient age and sex, keloid total size, maximal size, anatomical locations, number, and cause.

Fig. 6. Keloid on both helix and lobule.

Risk Factor Identification Using Multivariate Logistic Regression Analysis After we performed univariate analysis using the entire study sample (Table 2), all factors that were found to be significant to the 0.20 level were included in the multivariate logistic regression analysis (Table 3). The variables included in the analysis were age (p ⫽ 0.174), age of keloids (p ⫽ 0.017), growth rate (p ⫽ 0.012), previous treatment history (p ⬍ 0.001), and number of ear keloids (p ⫽ 0.178). We then performed backward stepwise elimination to ensure that only those variables significantly influencing keloid recurrence were included in the final logistic regression analysis. After multiple eliminations, the only factors that were found to play significant roles in keloid recurrence were growth rate (p ⫽ 0.002), body mass index (p ⫽ 0.009), and previous treatment history (p ⬍ 0.001). Table 3 illustrates the relative weights the three variables played in influencing keloid recurrence. Notably, the presence of previous treatment history (which includes surgical excision, steroid injection, combination therapies, and other treatments) had a 6.92 increased odds ratio of recurrence in comparison with absence of prior treatment history.

DISCUSSION

Fig. 7. Keloid on the left posterior auricular area.

cm/yr versus 0.42 cm/yr, p ⫽ 0.012). Patients with keloid recurrence were significantly associated with both higher body mass index and the presence of previous treatment history as compared with nonrecurrent cases (21.5 compared with 21.0, p ⫽ 0.017; and 92.6 percent compared with 67.3 percent, p ⬍ 0.001, respectively). No significant effects on keloid recurrence were noted for

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Ear keloids remain challenging reconstructive problems with serious aesthetic implications. Keloids are relatively resistant to treatment, and patients tend to experience high recurrence rates when treated with a single-treatment modality.16 Keloids have a tendency to recur after surgical excision alone, with rates up to 80 to 100 percent.17 According to the literature, radiation therapy is an effective adjuvant modality for treating earlobe keloids.18,19 However, in using radiation therapy, there is a risk of the development of radiationinduced malignancy.20 In our experience, many patients seen at our hospital have fears of possible radiation-induced malignancy after being told about radiation therapy at other hospitals. Although the mechanism of pressure therapy has not been fully determined, a combination of surgical excision and adjuvant pressure therapy is considered highly efficacious in reducing keloid recurrences, with minimal adverse effects.21 This effectiveness is hypothesized to occur as a result of altered wound tension and pressure-induced localized hypoxia.15 Numerous pressure earrings


Fig. 8. Keloid on the right posterior auricular area and gross specimen.

have been described as adjuvant therapies for ear keloids. Among them, magnet pressure therapy has several positive attributes, including ability to treat keloids on any portion of the ear (lobule, helix, and other regions), low cost, easy application and removal by patients, and no hearing impairment (Fig. 2). In the current study, recurrent cases were strongly associated with poor compliance to adjuvant pressure therapy. When using postoperative pressure therapy for the treatment of keloids, patient compliance is essential, as the keloid may recur as soon as the external pressure is relieved prematurely. Therefore, improved patient training may further decrease the recurrence rate of ear keloids when using this device. In addition, as our patients were recruited from a medical referral center for treatment of ear keloids, our cohort of patients tend to have symptoms that are more severe than those of average patients. If applied to average patients, we suspect that our protocol would yield more satisfactory outcomes than those of severe cohorts for ear keloids. Although ear keloids have been discussed extensively in the medical literature, only a few studies have focused on risk factors of keloid recurrence. Our study has yielded several novel and surprising observations on keloid recurrence. An interesting and novel observation was made regarding growth rate and keloid recurrence. In contrast to other studies, low growth rate was significantly associated with high recurrence rate.6 Surprisingly, the maximal diameter of the largest lesion of a single patient between the recurrent

and nonrecurrent groups was not a significant factor in recurrence. Nevertheless, longer duration of keloid presence before treatment partially explains the high recurrence rates associated with low growth rate, considering the inverse relationship between duration of disease and growth rate. Another unique finding was the association of previous treatment history with the risk of keloid recurrence. This relationship had been strongly suspected in our clinical practice and was therefore specifically investigated. Skin trauma including ear piercing, laceration, and blunt trauma can cause keloids, and previous treatment history is considered a form of trauma. The link between body mass index and keloid recurrence is also a novel finding. We found that high body mass index was associated with high keloid recurrence rates. This implies that obese patients are more likely to have recurrent ear keloids than those with normal body mass index. A recurrence risk assessment table (Table 3) was constructed that presents a prospective patient’s individualized risk based on these preoperatively identifiable characteristics, and this table has facilitated our preoperative counseling by changing how we can predict, to some degree, keloid recurrence. Strengths of this study include excellent follow-up rates with a constant follow-up period (outcome assessment at 18 months postoperatively for all patients). In addition, our study was a wellscheduled prospective outcome study in which patients were surveyed at predetermined times before and after surgery. Lastly, our study included

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Plastic and Reconstructive Surgery • August 2011 Table 2. Baseline Characteristics between Nonrecurrence and Recurrence Groups* No. of patients Continuous variables Age, years Total size, cm Maximal diameter, cm† Age of keloids, years Growth rate, cm/yr BMI, kg/m2 Categorical variables Sex Female Male Anatomical locations Lobule Helix Both lobule and helix Other portions Previous treatment history No Yes Previous treatment modalities None Surgical excision Steroid injection Excision plus steroid injection Excision plus pressure therapy Other treatments Cause Ear piercing Laceration Surgery Infection Idiopathic No. of ear keloids One Two Three Four Six

Nonrecurrence

Recurrence

789

97

24.00 (22.00–27.00) 2.00 (1.30–3.00) 1.50 (1.00–2.00) 3.00 (1.00–5.00) 0.50 (0.33–1.00) 21.00 (19.00–22.00)

23.00 (21.00–27.00) 2.00 (1.50–3.00) 1.50 (1.00–2.00) 3.00 (2.00–5.00) 0.42 (0.25–0.88) 21.50 (22.00–22.00)

p

0.174 0.410 0.964 0.017‡ 0.012‡ 0.017‡ 0.986

739 (93.7) 50 (6.3)

88 (93.6) 6 (6.4)

565 (71.6) 173 (21.9) 38 (4.8) 13 (1.6)

70 (74.5) 20 (21.3) 3 (3.2) 1 (1.1)

258 (32.7) 531 (67.3)

7 (7.4) 87 (92.6)

258 (32.7) 122 (15.5) 297 (37.6) 27 (3.4) 68 (8.6) 17 (2.2)

7 (7.4) 33 (35.1) 36 (38.3) 5 (5.3) 10 (10.6) 3 (3.2)

765 (96.9) 10 (1.3) 8 (1.0) 3 (0.4) 3 (0.4)

90 (95.7) 1 (1.1) 2 (2.1) 0 (0.0) 1 (1.1)

393 (49.8) 319 (40.4) 59 (7.5) 17 (2.2) 1 (0.1)

42 (44.7) 47 (50.0) 2 (2.0) 3 (3.2) 0 (0.0)

0.857

⬍0.001‡ ⬍0.001‡

0.442

0.178

*Values are median (interquartile range) for continuous variables and number (percentage) for categorical variables. The p values for continuous variables were obtained by using the Mann-Whitney test; p values for categorical variables were obtained by using chi-square tests or Fisher’s exact tests. †Maximal diameter means the maximal diameter of the largest lesion of a single patient. ‡Statistically significant.

the largest cohort ever conducted in any ear keloid study. This study also had some limitations. First, our patients were all Korean, and had more severe presenting symptoms compared with those in most other hospitals, as 70 percent of our patients had a history of treatment failure. For these reasons, our results cannot be generalized to patients in other circumstances. Second, recurrence risk assessment results are somewhat incomplete, as they do not provide adjustments for risk factors not included in our study such as additional keloid presentation, family history of keloids, and histopathologic findings.

CONCLUSIONS Ear keloids are a cosmetic disfigurement that is challenging to treat, with a high recurrence rate.

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The increasing trend for cosmetic piercing and for multiple ear piercing suggests that ear keloids will become a more frequent part of plastic surgery practice. There is no consensus as to the optimal treatment of keloids. As the treatment modality of surgical excision followed by postoperative pressure therapy provides reasonably positive results in the reviewed literature, our postoperative pressure therapy with a magnet is efficacious, safe, well tolerated, and successful at preventing recurrences. As patient compliance was poor in the recurrent cases, improved patient training may further decrease the recurrence rate of ear keloids when using magnets. Based on our study of 1436 keloids in 883 patients, two patient characteristics (patients with a prior treatment history or high body mass index) and one keloid characteristic

Volume 128, Number 2 • Ear Keloid article. The authors also acknowledge Mi-Yeon Lee for statistical assistance. REFERENCES

Fig. 9. Tissue necrosis after adjuvant pressure therapy using magnets.

Table 3. Multivariate Logistic Regression Analysis Keloid Recurrence Independent Variable Growth rate BMI Previous treatment history

Odd Ratio (95% CI)

p

0.67 (0.48–0.94) 1.16 (1.04–1.29) 6.92 (3.13–15.29)

0.020 0.009 ⬍0.001

CI, confidence interval; BMI, body mass index.

(keloid with low growth rate) were linked to risk of keloid recurrence. This information can be used to clinically counsel a patient on the individualized risk of keloid recurrence, and with this added information, patients and surgeons can make more informed decisions. However, a prospective multicenter study or meta-analysis would be beneficial in optimizing treatment to provide patients and surgeons with the best possible management of ear keloids. Choong Hyun Chang, M.D. Department of Plastic and Reconstructive Surgery Kangbuk Samsung Hospital Sungkyunkwan University School of Medicine 108 Pyung-Dong Jongno-Gu, Seoul 110-746, Korea [email protected]

ACKNOWLEDGMENTS

The authors acknowledge Yun-Joo Park, M.D., and Ji-Hae Park, M.D., for helpful assistance in editing the

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