Oral cancer on the gingiva in patients with proliferative leukoplakia: A study of 30 cases.

BACKGROUND: Proliferative verrucous leukoplakia, recently coined as proliferative leukoplakia (PL), is associated with a strong tendency to recur after treatment and an elevated rate of malignant transformation. We compared the clinical characteristics of patients with gingival PL with and without progression to oral squamous cell carcinoma.

METHODS: The patients were divided into two groups: group 1 included 33 patients with gingival PL that did not progress to cancer, and group 2 included 30 patients with PL who developed malignant transformation during follow-up. We compared age, sex, tobacco habit, clinical characteristics of gingival PL lesions, and location, tumor-node-metastasis (TNM) stage, and clinical characteristics of gingival malignancy between groups.

RESULTS: Female sex was predominant in the group with gingival cancer, and simultaneous involvement of the buccal mucosa, tongue, and palate was more common in this group than in the group without cancer. PL lesions were also largest in the group of patients with cancer. Most gingival cancer occurred in areas with teeth and took the form of oral ulceration. TNM stage I was most common.

CONCLUSIONS: The simultaneous presence of lesions on the buccal mucosa, grade of lesion extension, and presence of ulcerative lesion were significantly associated with gingival cancer in patients with PL.