title: Proliferative verrucous leukoplakia: high incidence of gingival squamous cell carcinoma.
abstract: BACKGROUND
  Proliferative verrucous leukoplakia (PVL) is a multifocal and progressive lesion of the oral mucosa, often associated with papillomavirus, seen mainly in older females, and characterized by a high recurrence rate and high rate of transformation into verrucous or oral squamous cell carcinoma (OSCC). The aim of this study was to analyse the clinical characteristics of a substantial group of patients with PVL, evaluating the characteristics of those who developed cancer, and comparing them with a group of patients with OSCC but no preceding PVL.
  
  
  METHODS
  A group of 30 patients with PVL was studied for the clinical aspects and characteristics, age, sex, location, recurrence, the appearance of new lesions, and the frequency of development of oral cancer. A disease control group was formed with 110 patients with OSCC chosen randomly from among those treated in the same Service in this period of time. The patients were grouped as PVL and no cancer (Group 1); PVL developing cancer (Group 2) and patients with OSCC without clinical lesions associated with PVL (Group 3).
  
  
  RESULTS
  The average age of the PVL patients (Groups 1 and 2 combined) was 70.97 +/- 12.73 years, of which 80% were women. Only 23.3% were cigarette smokers. The area most frequently affected with PVL was the lower gingiva. Recurrence after treatment was seen in 86.7%, and new lesions appeared in 83.3%. Many (63.3%) developed cancer (Group 2). Comparison of Groups 2 and 3 patients showed that those with PVL developing cancer were more likely to develop gingival carcinoma and also to be older, more often females, and less likely to smoke tobacco.
  
  
  CONCLUSIONS
  Cancer developing in patients with PVL manifested particularly on the gingiva.
authors.affiliation: Department of Stomatology, Oral Medicine, University General Hospital, Valencia University, Valencia, Spain. bagan@uv.es
authors.forename: Jose V
authors.initials: JV
authors.lastname: Bagan
authors.forename: Yolanda
authors.initials: Y
authors.lastname: Jimenez
authors.forename: Jose M
authors.initials: JM
authors.lastname: Sanchis
authors.forename: Rafael
authors.initials: R
authors.lastname: Poveda
authors.forename: Mari A
authors.initials: MA
authors.lastname: Milian
authors.forename: Judith
authors.initials: J
authors.lastname: Murillo
authors.forename: Crispian
authors.initials: C
authors.lastname: Scully
mesh_terms: D000367:Age Factors; D000368:Aged; D002294:Carcinoma, Squamous Cell / Q000473:pathology*; D018289:Carcinoma, Verrucous / Q000473:pathology; D002471:Cell Transformation, Neoplastic / Q000473:pathology*; D016009:Chi-Square Distribution; D005260:Female; D005887:Gingival Neoplasms / Q000473:pathology*; D006801:Humans; D007972:Leukoplakia, Oral / Q000473:pathology*; D008048:Lip Neoplasms / Q000473:pathology; D008297:Male; D008875:Middle Aged; D009364:Neoplasm Recurrence, Local / Q000473:pathology; D012737:Sex Factors; D012907:Smoking; D014062:Tongue Neoplasms / Q000473:pathology; D014860:Warts / Q000473:pathology