The evidence is mainly based on observational studies not including controls. However, the incidence of malignant transformation is clearly increased compared to incidence of oral squamous cell carcinoma from national surveys (Finland). Malignant transformation of OLP is associated with tobacco and alcohol consumption, HCV-infection and red (atrophic, ulcerative, bullous) subtype of OLP «Li JW, Li KY, Chan BWA, ym. Rate of Malignant Tran...»1, «González-Moles MÁ, Ramos-García P. An Evidence-Bas...»2, «Idrees M, Kujan O, Shearston K, ym. Oral lichen pl...»3, which are important to note for patient education.
| Reference | Study type | Population | Exposure | Outcomes | Risk of bias «Additional comments for included studies...»2 |
|---|---|---|---|---|---|
| «Li JW, Li KY, Chan BWA, ym. Rate of Malignant Tran...»1 | SR and MA | Patients with Oral lichenoid condition (OLP, OLL, LMD). 54 studies, n=24277 |
Oral lichenoid condition (OLP, OLL, LMD) | Primary outcome: the development of OSCC | NOS score ranged between 3 and 8 (28 studies scored ≥6 and 16 studies scored 5, while only one study scored 3). Only 7/54 studies fulfill the adequate follow-up duration (2 years or more). Publication bias cannot be ruled out. |
| «González-Moles MÁ, Ramos-García P. An Evidence-Bas...»2 | SR and MA | Patients with OLP, OLL, LR, OLP with dysplasia. 101 studies, n=38083 |
OLP, OLL, LR, OLP with dysplasia | Primary outcome: the development of OSCC | 11 studies were classified as having high methodological quality (QUIPS score ≥14/18) Not possible to dismiss the presence of publication bias. |
| «Idrees M, Kujan O, Shearston K, ym. Oral lichen pl...»3 | SR and MA | Patients with OLP. 33 studies, n=12838 |
OLP | Primary outcome: the development of OSCC | NOS score ranged between 2 (n=2) and 7 (n=4) |
| «Laniosz V, Torgerson RR, Ramos-Rodriguez AJ, ym. I...»4 | Retrospective case control study | Patients with OLP, n=303; age and gender matched controls, n=606 |
OLP | Development of OSCC | Low |
| «Iocca O, Sollecito TP, Alawi F, ym. Potentially ma...»5 | SR and MA | Patients with OPMD (LE, LP, OLL, OSF, PVL, dysplasia). 92 studies OLP 46 studies, n=14 362 OLL 5 studies, n=449 |
OLP, OLL | Development of OSCC | NOS, results not presented |
SR=Systematic review; MA=meta-analysis; OLP=oral lichen planus; OLL=oral lichenoid lesion; LMD=lichenoid mucositis with dysplasia; LR=lichenoid reaction; OSCC=oral squamous cell carcinoma; NOS=The Newcastle-Ottawa scale, QUIPS=Quality in Prognosis Studies tool; OPMD=oral potentially malignant disorder
| Reference | Comments |
|---|---|
| «Li JW, Li KY, Chan BWA, ym. Rate of Malignant Tran...»1 | Inclusion criteria: (1) Full-length, peer-reviewed original research papers published
in English from January 2003 to September 2022; (2) Observational studies providing
sufficient information on the diagnosis and rate of MT of OLCs. The rate of malignant
transformation (MT) in OLP patients diagnosed according to different diagnostic criteria
(the 2003 modified WHO criteria and non-2003 modified WHO criteria). Screening, identification
and reporting followed the PRISMA framework and analysis the MOOSE guidelines. Data
on MT were calculated as a pooled proportion (PP); subgroup analyses and possible
risk factors for MT were pooled as odds ratios (ORs). The quality of evidence was evaluated using the GRADE system. |
| «González-Moles MÁ, Ramos-García P. An Evidence-Bas...»2 | Updates the information (until Nov. 2023) published in the authors' previous meta-analysis
(until November 2018). Inclusion criteria: (1) Primary-level studies published in
English on the potential for malignancy of OLP; (2) longitudinal study design; (3)
if findings arise from overlapping populations of patients with OLP, priority was
given to the latest reported results or those offering more comprehensive data for
inclusion. The methodological quality and risk of bias of studies was evaluated using the QUIPS tool. The study complies with PRISMA statement and the MOOSE guidelines. |
| «Idrees M, Kujan O, Shearston K, ym. Oral lichen pl...»3 | Eligibility criteria: observational studies published in the English language from
2003 to January 2020 were included. The criteria for accepting OLP malignant transformation
included 1) OLP diagnosed according to the 2003 modifed WHO criteria and 2016 AAOMP
criteria, 2) oral carcinoma must have developed at the same location as previously
diagnosed OLP and the reported malignancies must have had follow-up of at least 6
mo before transformation to exclude concomitant presentation and 3) the patient's
demographics and medical history details should be clearly documented, the patient
must not be using any systemic immunosuppressive medication for at least 2 y at the
time of cancer diagnosis and the patient had no history of previous head and neck
malignancy, organ transplantation or chronic graft-versus-host disease. Was performed in accordance with PRISMA statement. NOS was modified to be combatible with the review's aims. |
| «Laniosz V, Torgerson RR, Ramos-Rodriguez AJ, ym. I...»4 | Patients who received their first occurrence of International Classification of Disease, Ninth Edition, code 697.0 or Hospital Adaptation of the International Classification of Diseases code 06970110 from January 1, 1986, through December 31, 2010, while a resident of
Olmsted County, Minnesota, USA. On the basis of the review of their medical records,
patients were classified as incident OLP cases if they met the following criteria:
1) the location was within the oral cavity (from lips to start of the oropharynx);
2) documented presence of the clinical or histopathologic, or both, characteristics
met the modified World Health Organization criteria; and 3) no prior history of OSCC
was found. Patients with a prior history of oral lichenoid lesions other than OLP
by histopathology or clinical examination were excluded from the study. The study did not match controls for potentially confounding factors, including tobacco and alcohol use. |
| «Iocca O, Sollecito TP, Alawi F, ym. Potentially ma...»5 | Given the observational nature of the included studies, the authors adopted a statistical
conservative approach; for this reason, a 99% confidence interval was chosen for calculations. Prespecified inclusion and exclusion criteria were used but not presented. The analysis was performed synthetizing cumulative MTR of different OPMDs excluding the dysplastic ones. A separate analysis was performed on the risk of MT of mild vs. moderate/severe dysplasia. Included studies with dysplasia and studies with no follow-up reported. Sensitivity analyses were made excl. studies with no follow-up reported. |
MT: malignant transformation; OLC=oral lichenoid condition; OLP=oral lichen planus; WHO=World Health Organization; AAOMP=American Association of Oral and Maxillofacial Pathology; NOS= The Newcastle-Ottawa scale; OSCC=oral squamous cell carcinoma; MTR=malignant transformation rate; OPMD=oral potentially malignant disorder
| Reference | Number of studies and number of patients | Follow-up time | Prevalence E | Absolute risk C | MT rate (95% CI) |
|---|---|---|---|---|---|
| Level of evidence: moderate The quality of evidence is upgraded due to the effect size and the consistency of the study results. |
|||||
| «Li JW, Li KY, Chan BWA, ym. Rate of Malignant Tran...»1 | 54 studies n=24277; 51 studies, n=22578 with OLP; 6 studies, n=717 with OLL; 4 studies, n=153 with LMD; 1 study, n=829, without differentiating OLP and OLL |
mean 16.8-272.4 months | 331/24277 (283/22578 OLP; 14/717 OLL; 11/153 LMD) |
PP for OLCs: 1.07 % [95% CI = 0.82–1.32]; OLP: 0.94% [95% CI = 0.70–1.19]; OLL: 1.95% [95% CI = 0.15–3.75]; LMD: 6.31% [95% CI = 2.30–10.32] |
|
| «González-Moles MÁ, Ramos-García P. An Evidence-Bas...»2 | 97 studies, n=36889 with OLP; 8 studies, n=856 with OLL; 4 studies, n=164 with LR; 5 studies, n=174 with OLP with dysplasia |
0.24-660 months | 606/38083 | PP for OLP: 1.43% (95% CI = 1.09–1.80); OLL: 1.38% (95% CI = 0.16–3.38); LR: 1.20% (95% CI = 0.00–4.25); OLP with dysplasia: 5.13% (95% CI = 1.90–9.43) |
|
| «Idrees M, Kujan O, Shearston K, ym. Oral lichen pl...»3 | 33 studies, n= 12838 | 1-10 years | 56/12838 | PP 0.2% [95% CI: 0.1%-0.3%] | |
| «Laniosz V, Torgerson RR, Ramos-Rodriguez AJ, ym. I...»4 | 1 study, n=909 (303 OLP, 606 controls) |
5-20 years | cumulative incidence of OSCC among the OLP cohort was 1.7%, 2.2%, 3.1%, and 3.1% at 5, 10, 15, and 20 years, respectively |
cumulative incidence of OSCC among the referent group was 0%, 0.2%, 0.2%, and 0.9% at 5, 10, 15, and 20 years, respectively |
HR 4.80, [1.24–18.6]; P = 0.02) |
| «Iocca O, Sollecito TP, Alawi F, ym. Potentially ma...»5 | 46 studies, n=14362 with OLP; 5 studies, n= 449 with OLL |
Ei eritelty OLP, OLL (laskettavissa taulukosta) |
OLP 190/14362 OLL 18/449 |
LP 1.4% (99% CI 0.9%-1.9%); OLL 3.8% (99% CI 1.6%-7.00%) |
|
E=exposure; CI=confidence interval; MT=malignant transformation; PP=pooled proportion; OSCC=oral squamous cell carcinoma; OLC=oral lichenoid condition; OLP= oral lichen planus; OLL=oral lichenoid lesion; LMD=lichenoid mucositis with dysplasia; LR=lichenoid reaction; HR=hazard ratio; OLP=oral lichen planus