Excimer Laser for Oral Lichen Planus

Oral lichen planus (OLP) is a chronic, inflammatory, mucosal variant of lichen planus.¹ Current treatment is aimed at controlling disease morbidity through lifestyle modifications and pharmacologic measures. Despite efforts, OLP often remains recalcitrant with frequent relapses. For such reason, alternative management methods are needed. The 308-nm excimer laser has demonstrated efficacy in the treatment of multiple inflammatory and pigmentary skin disorders.^2,3 The inflammatory infiltrate in OLP is primarily composed of T cells⁴ that can be directly targeted by the 308-nm excimer laser, making it a promising alternative to treat OLP.

Herein, this study aims to review the application of excimer laser for the treatment of OLP. Studies reviewed were published up until July 2019 and were obtained from MEDLINE/PubMed online database using the following terms oral lichen planus and excimer laser. 

Oral Lichen Planus

OLP is a T cell-mediated chronic inflammatory disease present in about 2% of the general population.^4,5 It predominantly affects adults older than 40 years and women more than men in a ratio of 1.4:1.⁴ OLP lesions preferentially form on the buccal mucosa, gingiva, and tongue.^6,7 Lesion presentation varies, ranging from asymptomatic white reticular striae (Figure) and erythematous patches to painful erosions, ulcers, and desquamative gingivitis.^6,8 

Figure. Oral lichen planus of the tongue.

The primary treatment goal of OLP includes alleviation of symptoms and minimizing morbidity. Patients with asymptomatic OLP often do not require treatment. Management incorporates lifestyle modifications, pharmacologic measures, and therapeutic interventions. Topical corticosteroids are the first-line option for local treatment. Additional local options include topical calcineurin inhibitors and intralesional corticosteroid injections, which commonly cause burning after application.^9,10 Systemic therapy includes corticosteroids, immunosuppressants, and biologics, which are primarily reserved for patients who fail to respond to local therapy or for patients with extraoral involvement.¹¹ Additional therapies such as topical and oral retinoids have been used with varying efficacy.¹¹ With most of these treatments, the short-term effects are satisfactory, but once the drug is discontinued, relapse is imminent. Recently, UV light-based modalities, photodynamic therapy, and laser therapies have been tried with reported success.^6,12-14 Curative success of available therapies is dependent on patient and disease characteristics. Thus, researchers are searching for novel therapeutic approaches.

Excimer Laser Uses in Dermatology

Excimer laser refers to a group of lasers operating in the UV range, with application in dermatology as a method for nonablative selective phototherapy. These are produced as a result of the dissociation of excited dimers formed by a mixture of a noble gas and a halide.¹⁵ The 308-nm xenon-chloride excimer laser is the most practical for dermatology due to its production of a 308-nm monochromatic coherent wavelength resting within the UV-B spectrum.¹⁵ While the 308-nm excimer laser shares the same indications as conventional phototherapy, it provides additional benefit in enhanced selectivity.¹⁶ A fiber optic cable directs the laser to affected areas, including difficult to reach locations such as the oral mucosa, while sparing the surrounding healthy tissue.¹⁵

The 308-nm excimer laser has shown to be efficacious in the treatment of multiple inflammatory and pigmentary skin disorders: vitiligo, psoriasis, atopic dermatitis, alopecia areata, granuloma annulare, lichen planus, cutaneous T-cell lymphoma, Langerhans cell histiocytosis, localized scleroderma, and genital lichen sclerosus.^2,3 It has been approved by the FDA for the treatment of psoriasis and vitiligo.³ No standard protocol exists regarding dose fluency, number of treatments, or maintenance. Nonetheless, excimer lasers have been an effective therapy regardless of method utilized in various protocols.^17,18

Excimer Use for OLP

A total of four studies were found using the 308-nm excimer laser for OLP. Within these four studies, only 26 patients with OLP were treated with the 308-nm excimer laser (Table^6,19-21).

Köllner et al¹⁹ treated eight patients with refractory OLP with excimer laser delivered through a special handpiece with angulated optics, to a spot size of 6 cm x 6 cm, three times per week. Starting dose was set at 75 mJ/cm² and was gradually increased up to 150 mJ/cm². Two patients saw no improvement, four patients saw improvement, and two patients achieved complete remission. Of those who achieved complete remission, both patients had biopsy-proven erosive OLP previously treated unsuccessfully with topical steroids or acitretin. At four months’ follow-up, one patient was disease-free whereas the other patient experienced disease recurrence. 

Trehan and Taylor⁶ reported a series of eight patients with refractory OLP receiving once-weekly treatments with excimer laser. The authors categorized responses as subjective improvement with respect to the patient’s baseline: poor (25%), fair (25%-50%), good (51%-75%), and excellent (75%). Starting dose was 100 mJ/cm² and was gradually increased by 50 mJ/cm² up to a maximum of 400 mJ/cm². Five patients had an excellent response, two had a fair response, and one had a poor response to treatment. Among patients in the excellent response groups, one participant remained in remission for more than one year, two were symptom-free for more than six months, and the last two participants achieved remission for two months. Investigators observed that erosive variants of OLP were associated with excellent response to therapies, suggesting that the lack of the overlying epithelial layer in the mucosa allows for a higher and consequently more effective UV dose to reach the infiltrating lymphocytes.⁶ Of note, the patient with a poor response carried a diagnosis of chronic active hepatitis C infection.⁶

Passeron et al²⁰ performed a pilot study with four patients presenting with erosive OLP. Only one of four patients with OLP showed clear improvement, two showed disease stabilization, and one showed worsening with excimer laser therapy treatments twice a week. Initial fluences of 50 mJ/cm² were increased 50 mJ/cm² every two sessions, up to a maximum of 200 mJ/cm². Side effects were limited to moderate erythema.

Liu et al²¹ reported a series of six patients with OLP treated with excimer laser. Three of six patients achieved partial remission, two achieved complete remission, and one remained stable. The initial dose of 250 mJ/cm² was gradually increased 10 mJ/cm² to 25 mJ/cm² once per week.

Despite the fact that these studies^6,19-21 employed different irradiation schemas and were performed at different times and environments, significant clinical improvement was achieved for most patients. Positive outcomes, such as complete symptom resolution and decreases in extent and severity of disease, were commonly achieved. Additionally, this technique resulted in high patient tolerance, faster healing, and prompt pain relief. Patients with erosive OLP seemed to respond better to this treatment modality. However, some patients showed no response to the treatment and one even experienced worsening of the disease. Further validation of this technique is essential.

Conclusion

Although the 308-nm excimer laser showed great promises in the treatment of OLP, results should be interpreted with caution due to small sample sizes and variable methods for result evaluation. Further randomized, controlled trials with long-term follow-up are needed to develop standard recommendations for the use, safety, and efficacy of excimer lasers for the treatment of OLP. n

Ms Puyana is a fourth year medical student and Dr Ashack is a PGY-4 Chief Dermatology Resident of the department of dermatology, University of Illinois at Chicago College of Medicine in Chicago, IL.

Disclosure: The authors report no relevant financial relationships.

References

1. Gorouhi F, Davari P, Fazel N. Cutaneous and mucosal lichen planus: a comprehensive review of clinical subtypes, risk factors, diagnosis, and prognosis. Sci World J. 2014;2014:742826. doi:10.1155/2014/742826

2. Mehraban S, Feily A. 308nm excimer laser in dermatology. J Lasers Med Sci. 2014;5(1):8-12.

3. Beggs S, Short J, Rengifo-Pardo M, Ehrlich A. Applications of the excimer laser: a review. Dermatol Surg. 2015;41(11):1201-1211. doi:10.1097/DSS.0000000000000485

4. Roopashree MR, Gondhalekar RV, Shashikanth MC, George J, Thippeswamy SH, Shukla A. Pathogenesis of oral lichen planus--a review. J Oral Pathol Med. 2010;39(10):729-734. doi:10.1111/j.1600-0714.2010.00946.x

5. McCartan BE, Healy CM. The reported prevalence of oral lichen planus: a review and critique. J Oral Pathol Med. 2008;37(8):447-453. doi:10.1111/j.1600-0714.2008.00662.x

6. Trehan M, Taylor CR. Low-dose excimer 308-nm laser for the treatment of oral lichen planus. Arch Dermatol. 2004;140(4):415-420. doi:10.1001/archderm.140.4.415

7. Eisen D. The clinical features, malignant potential, and systemic associations of oral lichen planus: a study of 723 patients. J Am Acad Dermatol. 2002;46(2):207-214. doi:10.1067/mjd.2002.120452

8. Schlosser BJ. Lichen planus and lichenoid reactions of the oral mucosa. Dermatol Ther. 2010;23(3):251-267. doi:10.1111/j.1529-8019.2010.01322.x

9. Byrd JA, Davis MD, Bruce AJ, Drage LA, Rogers RS 3rd. Response of oral lichen planus to topical tacrolimus in 37 patients. Arch Dermatol. 2004;140(12):1508-1512. doi:10.1001/archderm.140.12.1508

10. Samycia M, Lin AN. Efficacy of topical calcineurin inhibitors in lichen planus. J Cutan Med Surg. 2012;16(4):221-229. doi:10.1177/120347541201600403

11. Davari P, Hsiao HH, Fazel N. Mucosal lichen planus: an evidence-based treatment update. Am J Clin Dermatol. 2014;15(3):181-195. doi:10.1007/s40257-014-0068-6

12. Aghahosseini F, Arbabi-Kalati F, Fashtami LA, Djavid GE, Fateh M, Beitollahi JM. Methylene blue-mediated photodynamic therapy: a possible alternative treatment for oral lichen planus. Lasers Surg Med. 2006;38(1):33-38. doi:10.1002/lsm.20278

13. Kassem R, Yarom N, Scope A, Babaev M, Trau H, Pavlotzky F. Treatment of erosive oral lichen planus with local ultraviolet B phototherapy. J Am Acad Dermatol. 2012;66(5):761-766. doi:10.1016/j.jaad.2011.04.017

14. Khater MM, Khattab FM. Efficacy of 1064 Q switched Nd:YAG laser in the treatment of oral lichen planus [published online July 22, 2019]. J Dermatol Treatm. 2019:1-5. doi:10.1080/09546634.2019.1638881

15. Spencer JM, Hadi SM. The excimer lasers. J Drugs Dermatol. 2004;3(5):522-525.

16. Passeron T, Ortonne JP. Use of the 308-nm excimer laser for psoriasis and vitiligo. Clin Dermatol. 2006;24(1):33-42. doi:10.1016/j.clindermatol.2005.10.024

17. Mudigonda T, Dabade TS, Feldman SR. A review of protocols for 308 nm excimer laser phototherapy in psoriasis. J Drugs Dermatol. 2012;11(1):92-97.

18. Shen Z, Gao TW, Chen L, et al. Optimal frequency of treatment with the 308-nm excimer laser for vitiligo on the face and neck. Photomed Laser Surg. 2007;25(5):418-427. doi:10.1089/pho.2007.2086

19. Köllner K, Wimmershoff M, Landthaler M, Hohenleutner U. Treatment of oral lichen planus with the 308-nm UVB excimer laser--early preliminary results in eight patients. Lasers Surg Med. 2003;33(3):158-160. doi:10.1002/lsm.10202

20. Passeron T, Zakaria W, Ostovari N, Mantoux F, Lacour JP, Ortonne JP. Treatment of erosive oral lichen planus by the 308 nm excimer laser. Lasers Surg Med. 2004;34(3):205. doi:10.1002/lsm.20016

21. Liu WB, Sun LW, Yang H, Wang YF. Treatment of oral lichen planus using 308-nm excimer laser. Dermatol Ther. 2017;30(5). doi:10.1111/dth.12510