CHAPTER
Definition: Proliferative verrucous leukoplakia (PVL) 2, 3 is a rare oral leukoplakia characterized primarily by chronic proliferation (4.4-11.6 years1), exophytosis, confluence, refractoriness to treatment, and extremely high cancerization. It is referred to plainly as ‘oral leukoplakia’ (OL) before 20041. Thereafter, it is called PVL. The WHO classified it among the “potentially malignant disorders”2. When multifocal1, 3, it can be found in the buccal mucosa, gingiva, alveolar ridges, and tongue.
Epidemiology: Oral white lesions have a prevalence of 24.8% with 0.2 to 3.6% of which constitutes leukoplakia2. Over 86% of PVL becomes cancerous in 4.73 to 6.12 mean years (range: 1 to 20 years). It afflicts mostly females2, 1, the elderly (mean age at diagnosis: over 60 years) 2, 1, and non-smokers1. It has a death rate (over 30%) 4.
Provenance: First described in 19851, PVL initially develops as a white hyperkeratotic plaque2. Etiologically, it appears idiopathic, not associated with known cancer risks (e.g. tobacco, viruses, or fungi) 4, 5. Recurrences have been observed1.
Clinical features: PVL lesions occur bilaterally2. It has no distinct histological feature; no obvious growth from single to multiple foci; changing from simple epithelial hyperkeratosis (wart-like, erythroplakic) (Fig. 1) to verrucous hyperplasia or carcinoma or oral squamous cell cancer (OSCC). Genetic profile shows increased TGF-α; deletion or mutation of p16INK4α and P14ARF6. Trans-malignancy time is short (four months).
Prognosis: PVL is largely irreversible3; its prognosis poor2. Surgical treatment is inadequate due to high recurrence rate1, 5. Its trans-malignancy rate (40-100%1 and progression rate of 0.13-17.5%2) is predictive of oral cancer, particularly OSCC1.
Figure 1 - PVL with Keratosis (wavy) and exophytic wart-like configurations (Source4)
REFERENCES
1. Shaurya M, Ravindra S, Murthy S. Proliferative verrucous leukoplakia of the gingiva: a rare palatal presentation. J Adv Oral Res. 2012 Sep-Dec; 3(3):43-48 {2229-4120}.
2. Issrani R, Prabhu N, Keluskar V. Oral proliferative verrucous leukoplakia: a case report with an update. Contemp Clin Dent. 2013 Apr-Jun; 4(2):258-262 {DOI: 10.4103/0976-237X.114887}.
3. Ge L, Wu Y, Wu L, Zhang L, Xie B, Zeng X, Lin M, Zhou, Hong-mei Z. Case report of rapidly progressive proliferative verrucous leukoplakia and a proposal for etiology in mainland China. W J Surg Oncol. 2011; 9(1):26-29 {DOI: 10.1186/1477-7819-9-26}.
4. Sharma G, Das D, Naik P, Mukherjee J. HPV induced proliferative verrucous leukoplakia: case report. Intl J Healthcare Biomed Res. 2014 Jul; 2(4):58-62
{ISSN: 2319-7072}.
5. Garcia-Lopez R, Moya A, Bagan JV, Perz-Brocal V. Retroactive case – control study of viral pathogen screening in proliferative verrucous leukoplakia lesions. Clin Otolaryng. 2014; 39(1):272-280 {DOI: 10.1111/coa.12291}.
6. Agarwal N, Panat SR, Gupta P, Aggarwal A, Upadhyay N. Proliferative verrucous leukoplakia: a case report. J Dent Sci Oral Rehab. 2013 Jan-Mar; 41-43.
