Flashlamp pulsed dye laser (PDL) suppression of keloid proliferation through down-regulation of TGF-β1 expression and extracellular matrix expression

✍ Scribed by Yur-Ren Kuo; Seng-Feng Jeng; Feng-Sheng Wang; Tien-Hsing Chen; Hui-Chen Huang; Pei-Rong Chang; Kuender D. Yang

• Book ID: 102466739
• Publisher: John Wiley and Sons
• Year: 2004
• Tongue: English
• Weight: 190 KB
• Volume: 34
• Category: Article
• ISSN: 0196-8092
• DOI: 10.1002/lsm.10206

✦ Synopsis

Abstract

Background and Objectives

Keloids have been treated with flashlamp pulsed dye lasers (PDLs) with good results. We investigated whether PDL treatments induced keloid regression by decreasing growth factor‐β~1~ (TGF‐β~1~) induction, thereby reducing fibroblast proliferation and collagen deposition.

Study Design/Materials and Methods

Clinical evaluation and photography documented keloid height/texture, erythema, and pliability before and after PDL treatments scheduled at 2‐month intervals in 30 patients. Fluence per pulse was 10–18 J/cm^2^ (mean 14.0 J/cm^2^). Immunohistochemical (IHC) staining of TGF‐β~1~, proliferating cell nuclear antigen (PCNA), and collagen (types I and III) in extra‐cellular matrix was performed on 10 intra‐lesional or punch biopsies obtained before and 7 days after PDL treatments.

Results

Twelve months after final PDL treatments, keloid regression ( ≥ 50%) had occurred in 26/30 patients in whom erythema and surface irregularities had been reduced and pliability had been increased. In 4/30 patients, no changes in keloids had occurred after 12 months. Multiple treatments ( > 6) yielded better results than fewer treatments: 79% versus 50%, respectively. Marked keloid regression ( ≥ 90%) occurred in two patients who had received more than 10 treatments. IHC staining indicated that expression of TGF‐β~1~, PCNA and collagen type III, but not type I, was significantly reduced in keloid fibroblasts after PDL irradiation.

Conclusions

Keloids regressed following PDL‐induced reduction in TGF‐β~1~ expression, fibroblast proliferation, and collagen type III deposition. More than six PDL treatments at 2‐month intervals provided the best results. Lasers Surg. Med. 34:104–108, 2004. © 2004 Wiley‐Liss, Inc.