Photodynamic therapy (PDT) for oral leukoplakia: a systematic review and meta-analysis of single-arm studies examining efficacy and subgroup analyses

Abstract

Objective This study aims to evaluate the efficacy of photodynamic therapy (PDT) in the treatment of oral leukoplakia and explore the subgroup factors that may influence its effectiveness. Methods A systematic search was conducted in PubMed, Embase, the Cochrane Library, and Web of Science databases to identify relevant studies. Meta-analysis was performed using Stata15.0 software. Cochran’s Q test and I2 statistics were used to evaluate heterogeneity, egger’s test was used to evaluate publication bias. Results The analysis of 17 studies included in this study suggests that PDT may be effective in achieving complete response (CR) [ES = 0.50, 95%CI: (0.33,0.66)], partial response (PR) [ES = 0.42, 95%CI: (0.27,0.56)], no response (NR) [ES = 0.19, 95%CI: (0.11,0.27)]in patients with oral leukoplakia. The recurrence rate was also evaluated [ES = 0.13, 95%CI: (0.08,0.18)]. Subgroup analysis showed that various factors such as light source, wavelength, medium, duration of application, clinical and pathological diagnosis classification influenced efficacy of PDT. The lesion areas of the leukoplakia after treatment were reduced by 1.97cm2 compared with those before treatment. Conclusion Our findings show that PDT is a viable treatment for oral leukoplakia. However, the effectiveness of the therapy may depend on several factors, as suggested by our subgroup analyses. (Registration no. CRD42023399848 in Prospero, 26/02/2023)

Evaluating photodynamic therapy for oral precancerous lesions: Highlighting outcome measure of malignant transformation

“…Of 354 patients with complete response (CR) after treatment with PDT, recurrence was observed in 71 patients, and then the pooled recurrence rate (95% confidence interval [CI]) was 20.1% (16.2–24.6%). In the recent systematic review and meta-analysis, the pooled recurrence rate (95%CI) of oral leukoplakia patients received PDT was reported to be 13% (8–18%); 3 the pooled recurrence rate (95%CI) of oral leukoplakia and erythroplakia received PDT was reported to be 22.3% (16.1–29.9%). 4 Besides, we recently reported the pooled recurrence rate (95%CI) of OPL patients received scalpel surgery and laser therapy was 29.5% (26.3–33.0%) and 32.2% (26.1–38.9%), respectively.…”

“…Photodynamic therapy (PDT) is a minimally invasive treatment that uses exogenous light with a specific wavelength and photosensitizers to create molecular oxygen, which causes the death of tissue cells by necrosis, apoptosis, or autophagia. 3 In the recent updated systematic review and meta-analysis, the efficacies of PDT in the treatment of both oral leukoplakia and all oral potentially malignant disorders (including oral leukoplakia, erythroplakia, lichen planus, verrucous hyperplasia, actinic cheilitis) patients were systematically assessed. 3 , 4 Notably, clinical response (complete-, partial-, or no response) was the main outcome measure assessed in all the studies, recurrence was the secondary outcome measure assessed in a portion of the previous studies.…”

“… 3 In the recent updated systematic review and meta-analysis, the efficacies of PDT in the treatment of both oral leukoplakia and all oral potentially malignant disorders (including oral leukoplakia, erythroplakia, lichen planus, verrucous hyperplasia, actinic cheilitis) patients were systematically assessed. 3 , 4 Notably, clinical response (complete-, partial-, or no response) was the main outcome measure assessed in all the studies, recurrence was the secondary outcome measure assessed in a portion of the previous studies. 3 , 4 However, the effect of PDT on the primary outcome of OPL malignant transformation was not systematically evaluated.…”

“… 3 , 4 Notably, clinical response (complete-, partial-, or no response) was the main outcome measure assessed in all the studies, recurrence was the secondary outcome measure assessed in a portion of the previous studies. 3 , 4 However, the effect of PDT on the primary outcome of OPL malignant transformation was not systematically evaluated.…”

Laser therapy decreases oral leukoplakia recurrence and boosts patient comfort: a network meta-analysis and systematic review

“…However, PDT alone exhibits lower efficacy in managing OLK. Previous meta-analyses have indicated that PDT alone is effective in OLK management but has no clear advantage over surgery [ 56 , 57 ]. The diminished efficacy of PDT alone can be attributed to the poor penetration of the photosensitizer and the low absorption efficiency of the tissue.…”