Proliferative verrucous leukoplakia: a Brazilian multicenter study of 40 cases with exploratory assessment of contemporary diagnostic criteria.

OBJECTIVE: To describe the clinicodemographic and histopathological features of proliferative verrucous leukoplakia (PVL) in a multicenter cohort and assess the availability of variables required for retrospective application of contemporary diagnostic criteria. STUDY DESIGN: This retrospective multicenter study included 40 patients with PVL from four Brazilian referral centers. All cases met a clinicopathological case definition based on the World Health Organization description of PVL. Clinicodemographic, histopathological, and follow-up data were analyzed descriptively. Medical records were reviewed for documentation of variables required by diagnostic criteria. RESULTS: Most patients were female (85%); median age was 70 years. The gingiva/alveolar mucosa/retromolar area and buccal mucosa were the most frequent sites (55% each). At least two lesions were documented in 90% of patients, including three or more lesions in 72.5%. Nonhomogeneous morphology was documented in 47.5%. During a median follow-up of 3.8 years, recurrence occurred in 75% and malignant transformation in 22.5%. Patients underwent a median of two biopsies, showing findings ranging from hyperkeratosis to invasive squamous cell carcinoma. All variables required for retrospective application were documented in 24 cases (60%); at least one required variable was undocumented in 16 (40%). CONCLUSION: PVL exhibits marked clinicopathological heterogeneity and substantial malignant potential. Prospective documentation is essential for applying diagnostic criteria, improving comparability across studies, and guiding surveillance.