Malignant Transformation of Proliferative Verrucous Leukoplakia: A Description of the Clinical Oral Characteristics of These Squamous Cell Carcinomas

<b>Background/Objectives</b>: Proliferative verrucous leukoplakia (PVL) is an oral disorder with the greatest degree of malignant transformation. However, it is relatively rare. This study compared the clinical characteristics of patients with oral squamous cell carcinoma (OSCC) who had and had not been previously diagnosed with PVL. <b>Methods</b>: This case control study compared the clinical characteristics of patients classified as early (T1 and T2) or advanced (T3 and T4) OSCC according to the T size of the Tumor, Node, Metastasis (TNM) classification, including age, gender, location, and clinical type of oral squamous cell carcinoma. The analysis involved 140 patients. Group 1: 50 OSCC patients with PVL (OSCC-PVL) and Group 2: 90 OSCC patients without PVL (OSCC-noPVL). <b>Results</b>: The patients with OSCC-PVL were younger than those with OSCC-noPVL, but this did not reach statistical significance. Regarding patient gender, those with OSCC-PVL were much more frequently female (70%), while OSCC-noPVL was more prevalent in men (65.5%) (<i>p</i> < 0.01). There were also significant differences in the oral locations between the two groups: the gingiva was most prevalent in OSCC-PVL and the tongue in OSCC-noPVL. Erythroleukoplastic forms were significantly more common in OSCC-PVL (30% vs. 7.7%), while ulcerated forms were more frequent in OSCC-noPVL (63.3% vs. 42%). Finally, early T stages were much more prevalent in our patients with OSCC-PVL. <b>Conclusions</b>: We found that OSCC preceded by PVL was much more frequent in women, had less aggressive clinical forms, and had significantly more frequent early T stages than in OSCC-noPVL.