Synergistic Effect of 308 nm Excimer Laser Following Autologous Epidermal Grafting in Vitiligo

Dear Editor:

Stable vitiligo continues to pose a therapeutic challenge despite advances in surgical and phototherapy based interventions¹. Although autologous epidermal grafting and 308 nm excimer laser are widely used in clinical practice, monotherapies often achieve inconsistent or incomplete repigmentation, particularly in difficult anatomical sites²,³. To contribute additional real world evidence to this field, we would like to report our experience with a combined treatment strategy that integrates autologous tissue engineered epidermal grafting with 308 nm excimer laser therapy.

We retrospectively reviewed 57 patients with stable vitiligo managed at the Department of Therapeutics, Dalian Dermatosis Hospital, between July 2020 and August 2024. Patients received one of three regimens: excimer laser alone (n=20, involving 78 lesions), tissue engineered epidermal grafting alone (n=20, involving 72 lesions), or combined grafting followed by excimer laser therapy (n=17, involving 75 lesions). For the epidermal grafting group, the skin specimen was harvested from a concealed donor site under local anesthesia and transferred to a good manufacturing practice compliant laboratory. Epidermal cells were isolated using a modified Green method. The isolated cells were expanded in culture to generate tissue engineered epidermis containing melanocytes. After preparation of the recipient site by superficial dermabrasion, the engineered epidermis was applied to the lesion and secured with sutures and a pressure dressing. In the excimer laser group, treatment was administered 1–2 times weekly. In the combination group, excimer laser therapy was initiated 3 weeks after grafting and administered weekly. In both groups, treatment was continued until satisfactory repigmentation was achieved or until completion of the 12 month follow up. No systemic or topical treatments were administered during the study period in any of the three groups, and only basic skin care measures were permitted. The outcome was the percentage reduction in Vitiligo Area Scoring Index (VASI) from baseline at 12 months, and treatment responses were categorized according to thresholds (≥25%, ≥50%, and ≥75%).

Baseline demographic and disease characteristics were comparable across groups (Table 1). Repigmentation was observed earliest in the combination therapy group. The combined treatment group achieved the highest proportion of VASI 50 (90.7%), compared with 83.3% in the grafting group and 79.5% in the excimer laser group (p<0.05). Facial and truncal lesions demonstrated the most favorable responses in all groups, consistent with their richer follicular melanocyte reservoirs and superior vascularity⁴. Facial lesions showed marked repigmentation in nearly all patients receiving combination therapy. In contrast, acral lesions of the hands and feet remained the most resistant, achieving only partial repigmentation in a minority of cases regardless of treatment modality. Extremity lesions (arms and legs) showed intermediate responses and slightly lower improvement rates in the combined group, likely reflecting their higher proportion of previously treatment resistant lesions and the influence of mechanical friction around joint areas (Table 1).

Table 1. Baseline characteristics and lesion responses by body region in each treatment group.

Group		Excimer laser group (n=20; 78 lesions)	Epidermal grafting group (n=20; 72 lesions)	Combined group (n=17; 75 lesions)
Age (yr)		27.3±4.8	28.1±6.2	26.4±5.1
Age of onset		16.2±6.9	17.5±5.8	15.3±7.2
Male		12 (60.0)	11 (55.0)	7 (41.2)
Female		8 (40.0)	9 (45.0)	10 (58.8)
Segmental vitiligo		8 (40.0)	14 (70.0)	12 (70.6)
Non-segmental vitiligo		12 (60.0)	6 (30.0)	5 (29.4)
Facial lesions
	VASI 75	15 (57.6)	14 (66.7)	17 (70.8)
	VASI 50	9 (34.6)	4 (19.0)	6 (25.0)
	VASI 25	2 (7.7)	3 (14.3)	1 (4.2)
	< VASI 25	0 (0.0)	0 (0.0)	0 (0.0)
Trunk lesions
	VASI 75	10 (35.7)	13 (38.2)	20 (62.5)
	VASI 50	12 (42.9)	17 (50.0)	10 (31.2)
	VASI 25	6 (21.4)	4 (11.8)	2 (6.3)
	< VASI 25	0 (0.0)	0 (0.0)	0 (0.0)
Extremities lesions (arms/legs)
	VASI 75	8 (50.0)	7 (58.3)	8 (61.5)
	VASI 50	6 (37.5)	3 (25.0)	3 (23.1)
	VASI 25	2 (12.5)	2 (16.7)	2 (15.4)
	< VASI 25	0 (0.0)	0 (0.0)	0 (0.0)
Hands/feet lesions
	VASI 75	0 (0.0)	0 (0.0)	3 (50.0)
	VASI 50	2 (25.0)	2 (40.0)	1 (16.7)
	VASI 25	1 (12.5)	2 (40.0)	2 (33.3)
	< VASI 25	5 (62.5)	1 (20.0)	0 (0.0)
Total
	VASI 75	33 (42.3)	34 (47.2)*	48 (64.0)†
	VASI 50	29 (37.2)	26 (36.1)	20 (26.7)
	VASI 25	11 (14.1)	11 (15.3)	7 (9.3)
	< VASI 25	5 (6.4)	1 (1.4)	0 (0.0)

Values are presented as number (%) or mean ± standard deviation.

VASI: Vitiligo Area Scoring Index.

^*p<0.05 compared with the excimer laser group; ^†p<0.05 compared with both other groups.

Adverse events were mild and self limited across all groups. Excimer laser therapy most commonly induced transient pruritus, erythema, and occasional blistering, whereas grafting procedures produced short term postoperative pain. All reactions resolved spontaneously, indicating a favorable safety for both monotherapies as well as the combined approach.

Several biological mechanisms may help explain why combining tissue engineered epidermal grafting with excimer laser therapy enhanced repigmentation outcomes. Grafting directly supplies the lesion with viable melanocytes and keratinocytes, bypassing the limitations of depleted or dysfunctional melanocyte reservoirs in longstanding lesions⁵. Excimer laser therapy, through targeted ultraviolet B emission, induces local immunomodulation by promoting T-cell apoptosis, reduces IFN-γ driven inflammatory pathways, and stimulates the proliferation, migration, and differentiation of melanocyte stem cells⁶,⁷. Combining these two modalities therefore integrates cellular supplementation with photobiological activation and immune restoration, resulting in a synergistic effect that likely accounts for the superior repigmentation observed in our cohort.

These results should be interpreted with appropriate caution. The retrospective design, modest sample size, and single center setting introduce potential selection bias. The 12 month follow up period does not fully address long term durability or relapse rates. Although no statistically significant difference in clinical subtype distribution was observed among the groups, the higher proportion of segmental vitiligo in the grafting and combination groups may have influenced outcomes. Additionally, mechanistic explanations were inferred from existing literature and not examined directly. Prospective randomized controlled trials with larger populations and extended follow up are needed to confirm these preliminary findings.

In conclusion, our real world experience suggests that combining autologous tissue engineered epidermal grafting with 308 nm excimer laser therapy is a safe, well tolerated, and highly effective treatment option for stable vitiligo, particularly for lesions on the face and trunk. We hope these data will assist clinicians seeking to optimize therapeutic strategies for patients with stable disease.

This study involved a retrospective analysis of anonymized clinical data and did not include any intervention. The study was conducted in accordance with the ethical standards of the institutional ethics committee and with the Declaration of Helsinki. According to institutional policy and national regulations, ethical approval and informed consent were waived for this study. No identifying patient information was included.