Risk assessment of malignant transformation of oral leukoplakia in patients with previous oral squamous cell carcinoma.

The aim of this study was to identify the risk factors associated with developing oral squamous cell carcinoma (OSCC) from surgically excised oral leukoplakia (OL) in patients with previous oral cavity cancer. Clinicopathological data of 84 patients who were treated for OL between July 2002 and July 2020 and who had previously received treatment for OSCC were reviewed retrospectively. The follow-up time ranged from 0.69 to 17.99 years (mean 6.78 ± 4.25 years). The overall cumulative malignant transformation rate was 25% and the annual transformation rate was 5.73%. Kaplan-Meier survival analysis and the log-rank test showed that Candida infection (P = 0.010) was a risk factor associated with malignant transformation. In the multivariate Cox regression analysis, tongue and floor of the mouth as the location of the leukoplakia (P = 0.039), multifocal lesions of OL (P = 0.047), and Candida infection (P = 0.018) were the three independent prognostic factors related to the development of OSCC from the treated OL. A cautious approach to OL of the tongue with Candida infection or multifocal disease in this group of patients would be appropriate.

Yang SW ，Lee YC ，Lee YS ，Chang LC ，Lai YR ... -  《-》

Malignant transformation rate of oral leukoplakia in the past 20 years: A systematic review and meta-analysis.

This meta-analysis aimed to assess the rate of malignant transformation (MT) of oral leukoplakia (OL) and to study potential risk factors for the MT of OL into oral squamous cell carcinoma (OSCC). We performed a bibliographic search on nine electronic databases, including PubMed, MEDLINE, and Wanfang Data, for data on the MT rate of OL. Possible risk factors were calculated using Comprehensive Meta-Analysis and Open Meta [Analyst] software. The pooled proportion of OL MT for the total population described in the 26 selected studies was 7.20% (95% confidence interval: 5.40-9.10%). Nonhomogeneous type lesions, higher grades of dysplasia, the location of the lesion (tongue and multifocal), and female sex had significant effects on the MT of OL. OL tended to develop into OSCC (7.2%), and those with significant MT risk factors should be subjected to regular follow-up and observation. However, we require large-scale prospective studies to validate these results, together with unified clinicopathological diagnostic criteria, standardized risk factor recording/assessment methods, and long-term follow-up guidelines.

Guan JY ，Luo YH ，Lin YY ，Wu ZY ，Ye JY ，Xie SM ，Li J ... -  《-》

The combination of SMAD4 expression and histological grade of dysplasia is a better predictor for the malignant transformation of oral leukoplakia.

Xia RH ，Song XM ，Wang XJ ，Li J ，Mao L ... -  《PLoS One》

Overestimated risk of transformation in oral lichen planus.

Oral lichen planus (OLP) was classified as an oral potentially malignant disorder due to the association with oral squamous cell carcinoma (OSCC). However, the malignant potential of OLP has been controversial. Whether epithelial dysplasia should be differentiated from OLP and lichenoid dysplasia could be identified as a pathological entity has been the subject of debate. We recruited a large retrospective cohort with 3568 patients, and 10 of them developed OSCC. These cases were reviewed retrospectively to investigate association between OLP and OSCC. In 10 cases of OSCC, three of them were primary cancers distinct from the site with OLP, two were malignant transformation of proliferative verrucous leukoplakia, and five were malignant transformation of oral leukoplakia. All OSCC is not transformed from OLP. Therefore, previous insights into OLP might have overestimated its transformation risk. There may be the reasons: I. did not distinguish OLP from epithelial dysplasia, II. neglect of oral leukoplakia with dysplasia developed in the course after OLP, III. misdiagnosis in the early stage of proliferative verrucous leukoplakia. The pathological and molecular biological features of OLP differed from those of oral leukoplakia and OSCC. Strict control of the diagnostic criteria for OLP and close surveillance during the course could contribute to correctly identify the origin of OSCC and avoid overestimating the risk of OLP transformation.

Cai X ，Zhang J ，Zhang H ，Li T ... -  《-》

Malignant transformation of oral leukoplakia: a retrospective cohort study of 218 Chinese patients.

Liu W ，Wang YF ，Zhou HW ，Shi P ，Zhou ZT ，Tang GY ... -  《BMC CANCER》