Oral Lichen Planus: An Update on Diagnosis and Management

Oral lichen planus (OLP) is a chronic inflammatory disease whose pathogenesis involves a T-cell mediated, epithelium-directed inflammation in response to unknown antigen(s). The disease evolves by intermittent flares and displays polymorphous clinical features (reticular, erosive, atrophic, plaque, papular, bullous, etc.). When present, symptoms vary depending on the clinical form and range from discomfort to severe pain. Topical superpotent corticosteroids constitute the first-line treatment of symptomatic flares, whereas a wide range of second/third-line treatments are available among topical calcineurin inhibitors, systemic corticosteroids, systemic retinoids, topical/systemic immunomodulators, etc. Follow-up of patients is necessary to detect transformation into squamous cell carcinoma, occurring in approximately 1% of patients.

Cutaneous lichenoid drug eruptions: A narrative review evaluating demographics, clinical features and culprit medications

Cutaneous lichenoid drug eruptions (LDE) are adverse drug reactions (ADR) characterized by symmetric, erythematous, violaceous papules reminiscent but rarely fully characteristic of lichen planus (LP). We aimed to analyse the literature describing cases of LDE within the last 20 years to provide additional insight into culprit drugs, typical latency to onset of the eruption, the spectrum of clinical presentations, severity and management. A literature search was conducted in MEDLINE between January 2000 and 27 January 2021. The keywords 'lichenoid drug rash' and 'lichenoid drug eruption' were used. Cases were included if LDE diagnosis was made, and culprit drugs were identified. A total of 323 cases with LDE were identified from 163 published case reports and studies. The mean patient age was 58.5 years (1 month to 92 years), and 135 patients (41.8%) were female. Checkpoint inhibitors (CKI) were the most frequently reported culprit drugs (136 cases; 42.1%), followed by tyrosine kinase inhibitors (TKI) (39 cases; 12.0%) and anti-TNF-α-monoclonal antibodies (13 cases; 4.0%). The latency between initiation of the drug and manifestation was 15.7 weeks (range: 0.1-208 weeks). After discontinuing the culprit drug, the median time to resolution was 14.2 weeks (range: 0.71-416 weeks). One hundred thirty-six patients (42.1%) were treated with topical, and 54 patients (16.7%) with systemic glucocorticoids. Overall, we conclude that, albeit rare, LDE is challenging to diagnose ADR induced by mostly CKI, TKI, and biologics. Treatment modalities resemble that of lichen planus, and the culprit drugs had to be discontinued in only 26%, which is low compared with other types of adverse drug reactions. This is probably due to the low risk of aggravation (e.g. toxic epidermal necrolysis) if the drug is continued and the benefit/risk ratio favouring the drug, as is often the case in cancer therapy.

Outcome and long-term treatment protocol for topical tacrolimus in oral lichen planus

BACKGROUND AND OBJECTIVE

Topical tacrolimus has been shown to be beneficial in the treatment of oral lichen planus (OLP). However, long-term effects and its optimal application protocol with gradual reduction have not been studied. Accordingly, we analysed the clinical response of OLP to tacrolimus in our daily clinical practice with a focus on the optimal long-term therapeutic scheme.

METHODS

Retrospective analysis of all consecutive patients diagnosed with OLP and treated with topical tacrolimus (0.03% oral rinse) in a clinical setting between 2015 and 2020. The objective clinical response was measured by a 4-point scale (complete remission, major remission, partial remission and no response), and subjective impairment by a 3-point scale (severe, moderate and none).

RESULTS

Fifty-seven patients (74% women; median age: 66 years) were included. Fifty-six (98%) patients had prior treatment with topical steroids. After introduction of tacrolimus, objective remission (major or complete) was reached by 28%, 62%, 87% and 97% of patients after 3, 6, 12 and 24 months respectively. Subjective remission was reported by 16%, 48%, 69% and 83% after 3, 6, 12 and 24 months of treatment respectively. The treatment frequency could be gradually reduced from initially twice daily to once daily or less in 28%, 61%, 78% and 87% after 3, 6, 12 and 24 months respectively; 41% of patients completely suspended the treatment at one point, but 67% of them experienced a relapse after a median time of 3.3 months. Four patients (7%) developed a squamous cell carcinoma (SCC) during the observation period. Otherwise, there were only few and minor side-effects.

CONCLUSION

Topical tacrolimus can be an effective second-line therapy for OLP refractory to potent topical corticosteroids. The therapy frequency can often be reduced during the maintenance period. Both signs of clinical activity and subjective impairment should guide therapy. Regular follow-up is necessary to recognize possible SCC.

Lichen Planus

Lichen planus (LP) is a T cell-mediated disease affecting the stratified squamous epithelia of the skin and/or mucus membrane. Histologically, the disease is characterized by a lichenoid inflammatory infiltrate and vacuolar degeneration of the basal layer of the epidermis. LP has three major subtypes: Cutaneous, mucosal and appendageal LP. Rarely, it may affect the nails in the absence of skin and/or mucosal changes. LP may also be induced by several drugs, typically anti-hypertensive medication or be associated with infections, particularly viral hepatitis. The diagnosis is based on the clinical presentation and characteristic histological findings. Although the disease is often self-limiting, the intractable pruritus and painful mucosal erosions result in significant morbidity. The current first-line treatment are topical and/or systemic corticosteroids. In addition, immunosuppressants may be used as corticosteroid-sparing agents. These, however are often not sufficient to control disease. Janus kinase inhibitors and biologics (anti-IL-12/23, anti-IL17) have emerged as novel future treatment options. Thus, one may expect a dramatic change of the treatment landscape of LP in the near future.

Retrospective analysis of the clinical characteristics and patient-reported outcomes in vulval lichen planus: Results from a single-center study

Vulval lichen planus (VLP) is a rare, but often chronic, inflammatory disease whose symptoms include genital pain, discomfort, and dyspareunia. The clinical manifestations include erythema, erosions, and scarring. The aim of this study was to longitudinally investigate patient-reported outcomes and clinical findings in patients with VLP. Patients (>18 years) with histologically confirmed VLP were included in the retrospective analysis. Patient demographics, clinical features, symptomatology, quality of life, management, clinical outcomes, and comorbidities associated with VLP were analyzed. Twenty-four patients were identified with a mean (standard deviation [SD]) follow-up time of 19.3 (13.8) months. Classical VLP with glazed erythema was found in seven (29.2%) patients, erosive VLP was present in 15 (62.5%) patients, and hypertrophic VLP in two (8.3%). Seven patients had additional cutaneous involvement, while six patients had both vulval and oral mucosal involvement. The labia minora was the most frequently affected anatomical site (83.3%), followed by the clitoris (58.3%). Scarring lesions were found in 62.5% (n = 15) of patients. All study participants received treatment with potent and/or superpotent topical corticosteroids but 50% required systemic therapy (acitretin, corticosteroids, or hydroxychloroquine). Five (20.8%) patients underwent surgery due to adhesions and scarring resulting from VLP. One patient was diagnosed with a vulval squamous cell carcinoma during long-term follow-up. The mean (SD) Dermatology Life Quality Index score was 8.4 (5.5) at presentation and 8.9 (6.8) at the end of follow-up. In conclusion, VLP was associated with moderate quality of life impairments which persisted despite treatment, suggesting that current treatments for VLP are inadequate.

Efficacy of topical non-steroidal immunomodulators in the treatment of oral lichen planus: a systematic review and meta-analysis

OBJECTIVES

The aim of this systematic review was to assess the efficacy and safety of topical non-steroidal immunomodulators (TNSIs) for oral lichen planus (OLP) treatment.

MATERIALS AND METHODS

A search strategy designed for this purpose retrieved 1156 references. After analysis of titles and abstracts, 75 studies were selected for full-text analysis. Only randomized controlled clinical trials were selected, resulting in 28 studies included for qualitative and quantitative analysis.

RESULTS

The meta-analysis showed similar benefits in clinical response and symptom resolution between tacrolimus 0.1% and pimecrolimus 1% in comparison to topical steroids (TS). Pimecrolimus showed superior efficacy of clinical response but not for symptom resolution compared to placebo. Tacrolimus and pimecrolimus showed better performance preventing symptom relapse, while pimecrolimus also prevented clinical relapse better than TS. Cyclosporine was superior to placebo; however, TS showed better efficacy of clinical response. Thalidomide and retinoid were assessed in only one trial each, and both showed similar efficacy to TS. Rapamycin also presented similar clinical response to TS; however, the later showed greater reduction of symptoms. Mycophenolate mofetil 2% mucoadhesive was no better than placebo. No serious adverse effects have been reported. Cyclosporine showed a higher frequency and variety of adverse effects.

CONCLUSIONS

Topical tacrolimus and pimecrolimus are safe and effective alternatives for OLP treatment.

CLINICAL RELEVANCE

TS are usually the first choice for OLP treatment. Because some oral lesions may have a low response to treatment with TS, more topical therapeutic options, such as TNSIs, should be considered before systemic steroids are used.

Efficacy of topical non-steroidal immunomodulators in the treatment of oral lichen planus: a systematic review and meta-analysis

OBJECTIVES

The aim of this systematic review was to assess the efficacy and safety of topical non-steroidal immunomodulators (TNSIs) for oral lichen planus (OLP) treatment.

MATERIALS AND METHODS

A search strategy designed for this purpose retrieved 1156 references. After analysis of titles and abstracts, 75 studies were selected for full-text analysis. Only randomized controlled clinical trials were selected, resulting in 28 studies included for qualitative and quantitative analysis.

RESULTS

The meta-analysis showed similar benefits in clinical response and symptom resolution between tacrolimus 0.1% and pimecrolimus 1% in comparison to topical steroids (TS). Pimecrolimus showed superior efficacy of clinical response but not for symptom resolution compared to placebo. Tacrolimus and pimecrolimus showed better performance preventing symptom relapse, while pimecrolimus also prevented clinical relapse better than TS. Cyclosporine was superior to placebo; however, TS showed better efficacy of clinical response. Thalidomide and retinoid were assessed in only one trial each, and both showed similar efficacy to TS. Rapamycin also presented similar clinical response to TS; however, the later showed greater reduction of symptoms. Mycophenolate mofetil 2% mucoadhesive was no better than placebo. No serious adverse effects have been reported. Cyclosporine showed a higher frequency and variety of adverse effects.

CONCLUSIONS

Topical tacrolimus and pimecrolimus are safe and effective alternatives for OLP treatment.

CLINICAL RELEVANCE

TS are usually the first choice for OLP treatment. Because some oral lesions may have a low response to treatment with TS, more topical therapeutic options, such as TNSIs, should be considered before systemic steroids are used.

Diagnosis of oral lichen planus: a position paper of the American Academy of Oral and Maxillofacial Pathology

Despite being one of the most common oral mucosal diseases and recognized as early as 1866, oral lichen planus (OLP) is still a disease without a clear etiology or pathogenesis, and with uncertain premalignant potential. More research is urgently needed; however, the research material must be based on an accurate diagnosis. Accurate identification of OLP is often challenging, mandating inclusion of clinico-pathological correlation in the diagnostic process. This article summarizes current knowledge regarding OLP, discusses the challenges of making an accurate diagnosis, and proposes a new set of diagnostic criteria upon which to base future research studies. A checklist is also recommended for clinicians to provide specific information to pathologists when submitting biopsy material. The diagnostic process of OLP requires continued clinical follow-up after initial biopsy, because OLP mimics can manifest, necessitating an additional biopsy for direct immunofluorescence study and/or histopathological evaluation in order to reach a final diagnosis.

Oral lichen planus

Lichen planus is an inflammatory mucocutaneous disease that can affect the skin, hair, nails, and mucosal surfaces. Mucosal sites of involvement include oral, genital, ocular, otic, esophageal, and, less commonly, bladder, nasal, laryngeal, and anal surfaces. Oral lichen planus is a mucosal variant of lichen planus, which tends to affect women more often than men, with a typically more chronic course and potential for significant morbidity. Treatment can be challenging, and there is potentially a low risk of malignant transformation; however, therapeutic benefits can be obtained with various topical and systemic medications. Clinical monitoring is recommended to ensure symptomatic control. Increasing awareness and recognition of this entity have continued to fuel advances in therapy and in our understanding of the disease.

Cutaneous lichen planus: A systematic review of treatments

Various treatment modalities are available for cutaneous lichen planus. Pubmed, EMBASE, Cochrane Database of Systematic Reviews, Cochrane Central Register of Controlled Trials, Database of Abstracts of Reviews of Effects, and Health Technology Assessment Database were searched for all the systematic reviews and randomized controlled trials related to cutaneous lichen planus. Two systematic reviews and nine relevant randomized controlled trials were identified. Acitretin, griseofulvin, hydroxychloroquine and narrow band ultraviolet B are demonstrated to be effective in the treatment of cutaneous lichen planus. Sulfasalazine is effective, but has an unfavorable safety profile. KH1060, a vitamin D analogue, is not beneficial in the management of cutaneous lichen planus. Evidence from large scale randomized trials demonstrating the safety and efficacy for many other treatment modalities used to treat cutaneous lichen planus is simply not available.

Mucosal lichen planus: an evidence-based treatment update

BACKGROUND

Mucosal lichen planus (MLP) is a chronic mucosal disorder that often poses a therapeutic challenge to dermatologists, dentists, and gynecologists. To relieve patients' pain and discomfort, improve their quality of life, and achieve clinical improvement, various therapeutic approaches can be considered for this disease. Based on the current literature it is difficult to define any particular treatment as the main therapeutic modality.

OBJECTIVE

We aimed to systematically review the current literature for the effectiveness of available treatment modalities for MLP.

METHODS

All of the randomized controlled trials and systematic reviews of MLP were collected by searching Pubmed, EMBASE, the Cochrane Database of Systematic Reviews, Database of Abstracts of Reviews of Effects, Cochrane Central Register of Controlled Trials, Health Technology Assessment Database, and China National Knowledge Infrastructure. Meta-analysis was performed, if possible.

RESULTS

Topical betamethasone valerate, clobetasol-17-propionate, and fluocinonide are effective in the treatment of oral lichen planus (OLP) when compared with placebo. Calcineurin inhibitors and topical retinoids are also beneficial treatment options.

LIMITATIONS

The review does not include therapies with a lower level of evidence.

CONCLUSION

Topical corticosteroids are the mainstay of therapy for OLP. High-quality evidence is lacking for the treatment of lichen planus.

Oral lichen planus: focus on etiopathogenesis

Lichen planus is a chronic mucocutaneous inflammatory disease, which frequently affects the oral mucosa of white females over 40 years old. Its aetiology remains uncertain and the pathogenesis is still the object of much speculation. The present paper presents the most well known antigens, and describes the action of different cells and proteins associated with the development of that disease, as well as the possible agents involved with its malignant transformation. Different external agents, especially virus, and internal agents, like stress, and the heat shock protein antigen expression, associated or not, can alter the basal keratinocytes of the oral mucosa making them susceptible to apoptosis by CD8(+) cytotoxic T cell as well as activate matrix metalloproteinase and mast cell degranulation, which produce a great range of inflammatory mediators and cytokines determining the clinical onset of the disease. Regarding carcinogenesis, since it is a complex process and presents multifactorial origin, it is believed that there may be a synergism between intrinsic, such as inflammation mediators, and extrinsic agents (tobacco, alcohol, viral infections) for the OLP malignant transformation to occur. However, further studies are needed to better understand the origin, pathogenesis and process of malignant transformation of OLP.