To explore the application of photodynamic therapy (PDT) combined with orally administered retinoic acid in the treatment of proliferative verrucous leukoplakia (PVL) and provide a reference for clinical practice.

A case of sequential treatment of PVL with PDT and orally administered retinoic acid was reported. The characteristics, diagnosis, treatment of PVL, and the application of PDT and retinoic acid in oral leukoplakia were retrospectively analyzed based on the literature.

After four PDT sessions, a majority of the oral lesions were eliminated in a patient clinically diagnosed with PVL, but the lesions recurred two months later. Subsequently, the patient was treated with retinoic acid at a dose of 10 mg, once a day, orally before bedtime. After continuous treatment for 2 weeks, the oral lesions were significantly reduced. The dose was then adjusted to 10 mg, twice a day, and the treatment was extended for 3 months until the lesions completely disappeared. Following this, a periodic regimen was adopted to continue the administration of retinoic acid at a dose of 10 mg, twice a day (3 weeks of treatment followed by 1 week of drug withdrawal as one cycle), for a total of 6 cycles. No recurrence was observed during the 5-month follow-up after drug withdrawal. A review of the literature indicates that PVL is an oral potentially malignant disorder (OPMD) characterized by multifocality, high recurrence rate, and high malignant transformation rate. Currently, there is no ideal treatment method for PVL. PDT is advantageous because of its low toxicity. Furthermore, it is strongly selective, minimally invasive, and patients experience no scarring. Thus, it has been recommended as the first-line therapy for PVL. However, due to the limitations of local application of photosensitizers in terms of effectiveness, targeting, and penetration depth, the efficacy of PDT in treating PVL remains uncertain. There are a few reports on the treatment of oral leukoplakia with retinoic acid given by oral, but no literature has reported the combination of PDT and retinoic acid given by oral for PVL.

The sequential combination of PDT and oral retinoic acid therapy is an effective treatment for PVL.