2017-18 HSC Section 4 Green Book

Plastic and Reconstructive Surgery • September 2014

Fig. 3. A questionnaire was used to determine patient improvement in seven physical complaints in a percentage fashion compared before and after treatment, subdivided into patients without scar recur­ rence ( blue ) and patients with scar recurrence ( red ).

et al. used a 6 × 3-Gy schedule and found a 4.7 percent recurrence rate in a large population of 169 patients. 25 However, the radiation dose used by Guix et al. was prescribed at 1.0 cm from the source axis, which corresponds to a total dose of approximately 6 × 6 Gy at 0.5 cm from the source axis. 25 Kuribayashi et al. used superficial brachy- therapy with a 4 × 5-Gy schedule and found a 9.7 percent recurrence rate in 21 patients. 26 Finally, Garg et al. 27 found a 12 percent recurrence rate with a 3 × 5-Gy schedule in 12 patients, but all patients had previously received external beam radiation therapy. 12 Radiation Protocol The radiation protocol as used in this study (2 × 6 Gy administered in two fractions; the first within 4 hours after surgery and the second within 24 hours) has never previously been published. 4,9 We believe that the radiation dose and schedule have contrib- uted to the low rates of recurrence reported. First, a low total radiation dose limits damage to healthy surrounding tissues and reduces the risk of com- plications, two factors that could otherwise contrib- ute to a higher recurrence rate. Second, we find the timing of the first radiation dose to be of great importance. Although other studies mostly began the first procedure within 24 hours, 12,25,26 our first fraction was given within 4 hours. We believe that immediate postoperative adjuvant radiotherapy prevents immune cells from invading and prolif- erating into the lesion, reducing recurrence. This hypothesis is supported by several other groups treating keloids immediately after surgery or even perioperatively. 27–29

Interestingly, radiation therapy to prevent heterotopic ossification is nowadays even admin- istered preoperatively instead of postoperatively after extensive research by Kantorowitz et al. 30–32 Finally, this radiation schedule required patients to return to the outpatient clinic only once for the second radiation treatment, enhancing patient convenience. Cutaneous Malignancy Because we used a relatively low radiation dosage, complications such as radiation-induced wound dehiscence, dermatitis, neuritis, and cuta- neous malignancy were not seen. Although one might assume a small theoretical risk of develop- ing radiation-induced malignancy to exist, to our knowledge, no treatment-related cancers have been reported in the keloid management litera- ture. 33–35 In addition, because the theoretical risk of tumor induction is dependent on the total irra- diated volume, we used brachytherapy instead of external beam radiation therapy, in which the radiation volume is typically much larger. Pigmentation Changes and Physical Complaints Pigmentation changes (both hypopigmenta- tion and hyperpigmentation) were reported in 21.4 percent of the patients at long-term follow- up. Other studies reported equal or lower rates of pigmentation problems (0 to 17 percent). 9,12,24–26 Importantly, publications describing low rates of pigmentation problems included mostly patients with Fitzpatrick I to IV skin type. 12,24,25 Our data show that the incidence of pigmentation prob- lems is higher in African American patients

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