Malignant transformation of oral leukoplakia in a well‐defined cohort of 144 patients

Abstract

Objectives Oral leukoplakia is a potentially malignant disorder of the oral mucosa. The aim of this retrospective study was to identify the factors that possibly predict malignant transformation in a well‐defined cohort of patients with a long‐term follow‐up. All leukoplakias were staged according to a clinicopathological classification and staging system. Furthermore, a certainty factor has been used with which the diagnosis has been established. Material and methods The group consisted of 144 patients. The size, presence and degree of epithelial dysplasia were incorporated into a clinicopathological classification and staging system. Initial management consisted of surgical excision, CO2 laser vaporisation or observation only. The mean follow‐up period was 51.2 months (s.d. = 39.33, range 12–179 months). Results In 16 of 144 patients (11%), malignant transformation occurred between 20 and 94 months (mean 57.0 months) after the first visit, the annual malignant transformation rate being approximately 2.6%. A large size of the lesion (≥ 4 cm) showed to be the only statistically significant predictor of malignant transformation (P = 0.034). Conclusion A size of ≥ 4 cm showed to be the only significant predicting factor of malignant transformation in oral leukoplakia. No other epidemiological, aetiological, clinical or histopathological parameters were of statistical significance.

The treatment of oral leukoplakia with the CO2 laser: A retrospective study of 65 patients

“…Several treatments have been suggested in the literature, including surgery, electrosurgery, cryosurgery, topical agents (bleomycin, vitamin A), systemic agents (b-carotene, lycopene, retinoids), CO 2 laser and photodynamic treatment, although surgery and CO 2 laser are most frequently used. There is still no evidence that treatment prevents malignant transformation, although it seems advisable to treat oral leukoplakia with or without dysplasia (Horch et al, 1986;Chandu and Smith, 2005;Van der Waal, 2009;Santos et al, 2010;Yang et al, 2011;Song and Franco, 2011;Brouns et al, 2014) Q1 . 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 New technologies and improvements in oral and maxillofacial surgery and especially in laser surgery prove less invasive and more comfortable for patients.…”

“…At a workshop coordinated by the WHO in 2005, "potentially malignant disorder" was the preferred terms, with the working group agreeing that the term leukoplakia should be used to recognize "white plaques of questionable risk having excluded (other) known diseases or disorders that carry no increased risk for cancer" (Warnakulasuriya et al, 2007). Prevalence of oral leukoplakia is reported to be approximately 2% (Petti, 2003;Brouns et al, 2013aBrouns et al, , 2013b and the annual malignant transformation rate is estimated to be between 0.13% and 17.5% (Deppe et al, 2012;Kumar et al, 2013;Brouns et al, 2014). Leukoplakia is considered to be the most common premalignant lesion of the oral cavity; its occurrence is related to smoking, with alcohol as an independent factor.…”

Oral diseases diagnosis rate during an oral cancer prevention campaign in Fernandópolis, Brazil, 2014

“…Malignant transformation rates for leukoplakia lesions are variable, depending on the sample selection and the follow-up time; Lončar-Brzak et al [14], have reported among 139 leukoplakia lesions, malignant evolution rate on a 10-year follow-up period was 0.64%. More recently, Brouns et al [5] reported a malignant transformation rate for leukoplakia lesions of approximately 2.6% among 144 lesions studied on a 51-month follow-up period. Although leukoplakia malignant transformation rates are apparently lower when compared to erythroplakya lesions malignant potential [29] the risk for malignant evolution is clear, therefore, patients diagnosed with leukoplakia lesions during this campaign will have adequate clinical followup, and, if necessary, therapeutic approach will be performed.…”

The most difficult task

“…And although most of them are small with short follow up, retrospective in nature and biased, i.e. unable to provide sound (and even notso-sound) evidence, the results of some of the best did not show significant benefits of surgical treatment [3][4][5].…”

“…A treatment that is useless in nine time out of ten should be, at least, absolutely safe. Something that is not true for a number of medical treatment proposed [6], and probably for surgery, particularly for large lesions (which, by the way, are those at higher risk) [4,5,7].…”