Scar Keloid
Conditions
Keywords
Keloid, Botulinum Toxin type A, Radiotherapy
Brief summary
The prospective, split-scar, double-blind, randomized controlled study will enroll the patients who are older than 20 years with progressive keloid lesion which is symmetric. Botulinum toxin A will be injected into half of each keloid revision wound immediately after skin closure. The scars will be assessed at 1-year follow-up with Vancouver Scar Scale (VSS), Patient and Observer Scar Assessment Scale (POSAS), and the Cutometer.
Detailed description
Continuous variables will be reported as the mean ± standard deviation(SD). Each aspect of the VSS score, POSAS score, and the Cutometer parameters of each scar half between the BTA and control groups will be analyzed longitudinally using the paired t test. The interrater consistency will be evaluated using the Spearman rho. All analyses will be performed with IBM SPSS Version 23.0 (IBM Corp., Redmond, Wash.). A value of p \< 0.05 is considered to indicate statistical significance. The sample size was calculated based on the results of the investigators' aforementioned study published in 2019. Thirty patients underwent keloid revision and then received radiation therapy based on our treatment protocol. The postoperative Vancouver Scar Scale score was 4.15 ± 1.74. If treatment could improve VSS score by 1, which was considered clinically significant, approximately 26 patients would have been necessary to provide a result with a real significance (using the same SD and considering the standard α error of 0.05 and a power of 0.8). Assuming a 20% non-compliance rate for follow-up evaluation, the sample size was increased to 32 patients.
Interventions
After the whole surgical procedures of keloid revision are done, the participants will receive Botulinum Toxin type A (BTA) injection. The investigators split the scar into the right side and the left side. BTA and 0.9% saline, respectively, are used for the two arms of the study. Vials containing 100 units of BTA (BotoxⓇ, Allergan) are mixed with 2mL 0.9% injectable saline. The injection depth will be the intradermal layer. Injections will be performed with a 30-gauge needle and 1 mL syringe. Just before skin closure, the entire scar was treated, with sides randomized to receive treatment with either BTA or 0.9% normal saline. The dosage is 8 units / cm based on aforementioned studies. The maximal dose won't exceed 100 units.
DRUG0.9% Sodium Chloride Injection
After the whole surgical procedures of keloid revision are done, the participants will receive 0.9% saline injection. The investigators split the scar into the right side and the left side. BTA and 0.9% saline, respectively, are used for the two arms of the study. Only 0.9% saline is injected on the control side. The injection depth will be the intradermal layer. Injections will be performed with a 30-gauge needle and 1 mL syringe. Just before skin closure, the entire scar was injected, with sides randomized to receive treatment with either BTA or 0.9% normal saline. The dosage is 0.16 mL / cm.
Sponsors
Tainan Hospital, Ministry of Health and Welfare
National Cheng-Kung University Hospital
Study design
Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
PREVENTION
Masking
DOUBLE (Subject, Outcomes Assessor)
Eligibility
Sex/Gender
ALL
Age
20 Years to No maximum
Healthy volunteers
Yes
Inclusion criteria
* Adult (20 years or older) * Progressive keloid lesion that is bilaterally symmetric, mandibular area, anterior chest or suprapubic area, for example * At least 4 cm in length * Repeated or uncontrolled recurrence, and unendurable symptoms with poor response to conservative modalities * Valid written informed consent provided for surgery and trial inclusion
Exclusion criteria
* Allergy to botulinum toxin * Previous botulinum toxin injection at the lesion within 6 months before enrollment * Myasthenia gravis * Focal infection signs * Pregnant or breastfeeding woman
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Keloid recurrence | One year | The recurrence of keloid will be determined by clinical examination evaluated by a dermatologist. |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Subjective symptoms | 3, 6, 9 and 12 months | The subjective symptoms will be measured by the Patient Scale of the Patient and Observer Scar Assessment Scale. The Patient Scale consists six items and scores from 1 to 10 for each items. The score of 1 means much alike the normal skin and the score of 10 means worst imaginable scar. |
| Objective symptoms | 3, 6, 9 and 12 months | The subjective symptoms will be measured by the Observer Scale of the Patient and Observer Scar Assessment Scale. The Observer Scale consists six items and scores from 1 to 10 for each items. The score of 1 means much alike the normal skin and the score of 10 means worst imaginable scar. |
| Vancouver Scar Scale | 6 and 12 months | One dermatologist will evaluate the scar with the Vancouver Scar Scale. The Vancouver Scar Scale consists 4 items. The minimum score is 0, which means the scar is much alike normal skin. The maximal score is 13, which means purple, hyperpigmentation, contracture and elevated scar. |
| Scar firmness | 6 and 12 months | The scar firmness is determined by the Cutometer parameter R0. R0 is maximum amplitude of the curve (the total elongation). The larger R0 is, the softer the scar is. |
Countries
Taiwan
Outcome results
None listed