Extracorporeal photochemotherapy and methotrexate in the treatment of atypical oral lichen planus

Background: Some authors have successfully used methotrexate in the treatment of atypical oral lichen planus (LP) and noted its good tolerability. High clinical efficacy of the extracorporeal photochemotherapy (ECP) has been also reported in the treatment of such patients. However, there is no information on the long-term results of methotrexate and ECP and their combination in the treatment of atypical LP. Aim: To study clinical efficacy and long-term results of the combination of routine therapy with the ECP course and a single injection of methotrexate at a dose of 10 mg in patients with atypical LP of the oral cavity and the skin. Materials and methods: This was a prospective study with an active control. Eighteen (18) patients with various forms of atypical LP of the oral cavity (hypertrophic, erosive/ulcerative, exudative/hyperemic forms) and the skin (hypertrophic, pigmented, atrophic, follicular forms) were administered the combination of routine therapy (chloroquine, doxycycline, vitamin B₆, topical corticosteroids), an ECP course, and a single injection of methotrexate at a dose of 10 mg. Two hours before the ECP session all patients were given 8-methoxypsoralen. Peripheral mononuclear cells were isolated with a cell separator and treated with ultraviolet radiation (λ = 320–400 nm), then the monocyte cell mass was re-infused to the patient. The treatment course included 4 sessions performed every other day. A single injection of methotrexate was given in the middle of the ECP course. Clinical efficacy was assessed with the Thongprasom scale of activity of the disease and by visual analog scale (VAS) for pain assessment in patients with oral lesions. Results: The treatment was well tolerated and was not associated with methotrexate-related immune abnormalities. At one month after the 4^th ECP session, the mean Thongprasom score was decreased from 5 to 2.2 ± 1.2 (p < 0.001). At Week 24 after the treatment, 15 (83.2%) of patients had no painful symptoms (VAS score of 0). The clinical effect was associated with a significant decrease in correlation of CD3⁺CD8⁺ cells with СD38⁺ (r = 0.47, p > 0.05). Assessment of the results in the time period from 1 to 3 years (mean, 2.25 ± 0.96 years) showed no relapse in 13 (72.2%) of patients, and at 3 years, there was no recurrence in 7 cases (38.9%). Conclusion: The results obtained enable to consider the method of combination therapy with ECP plus a single intramuscular injection of methotrexate at a dose of 10 mg as an alternative therapeutic approach to refractory lesions of atypical LP of oral cavity.