Oral lichen planus – the importance of interdisciplinary approach

Oral lichen planus – general aspects

Lichen planus (LP) is a multifactorial condition with a chronic course and a complex immunological mechanism. Historically, the clinical lesions were first described in 1869 by Erasmus Wilson, and a few years later, the histological characteristics were outlined by Dubreuil (1906) and Darier (1909). Over time, this condition has been the subject of numerous studies, leading to significant progress in understanding its etiopathogenic mechanism. However, this aspect remains only partially elucidated to this day. Recent research suggests the involvement of complex immunological mechanisms, with T cells activated by various antigens playing a key role^(1-3).

Lichen planus is a mucocutaneous dermatosis with multiple sites of manifestation, including the oral mucosa, skin, nails, genital mucosa, and esophageal mucosa. Among these, oral and cutaneous involvement is the most common. Nearly half of patients develop both cutaneous and oral lesions simultaneously at some point during the disease course, while in about a quarter of cases, LP manifests exclusively in the oral cavity. Multiple sites of involvement do not necessarily indicate the severity, and the simultaneous presence of lesions in different areas of the body can be limited in time⁽⁴⁾.

The clinical appearance of oral lesions is quite specific, presenting in four forms that rarely occur in isolation. Keratotic, atrophic, erosive or bullous lesions can be observed in varying proportions within the same patient, with the predominant type determining the clinical form of lichen planus. In 95% of cases, the lesions are located bilaterally on the buccal mucosa, and the most common clinical form is reticular keratosis. These features are also the clinical criteria for the diagnosis of oral lichen planus. The symptoms reported by the patient vary and correlate with the clinical type and the extent of the lesions^(5,6).

Particularities of oral lichen planus
and their practical implications

Unlike the cutaneous form, oral lichen planus (OLP) has a chronic course characterized by exacerbations and remissions, an inconsistent therapeutic response, and the potential for significant complications. For this reason, early diagnosis and patient monitoring are essential. While the oral manifestation of lichen planus shares common features with other locations, it also presents certain specific characteristics. These lead to four key particularities of OLP, which carry important practical implications⁽⁷⁾.

Polymorphic clinical appearance and the challenge of diagnosis

One of the important clinical features of OLP is the polymorphic nature of its lesions. Oral lichen planus rarely manifests as a pure clinical form. More commonly, several types of lesions coexist in varying proportions. This can make it difficult to establish a correct diagnosis based solely on clinical criteria. Histopathological examination is crucial in confirming the diagnosis and for ruling out other pathologies with similar clinical appearances. In cases of ulcerative or erosive LP, histopathological examination should be supplemented by direct immunofluorescence testing to exclude the diagnosis of bullous dermatoses^(8,9).

Symptomatology, functional impairment and quality of life in patients with oral lichen planus

Depending on the predominant clinical form and the number of affected topographical areas, the symptoms reported by patients can vary. Erosive clinical forms are often accompanied by pain and burning sensations in the oral cavity, as well as significant functional impairments. In acute forms, characterized by lesions affecting more than three areas of the oral mucosa, the patients’ quality of life is notably compromised. In terms of symptomatology, OLP differs from cutaneous manifestations, where patients’ complaints are usually mild or resolve with recommended topical treatment. Therefore, the primary goal of OLP treatment is to alleviate symptoms and ensure an adequate quality of life^(10,11).

Recurrent nature, chronic course and unsatisfactory response to treatment

Unlike the cutaneous form, where recurrences after the initial episode are relatively rare, oral lichen planus exhibits a prolonged course marked by episodes of exa­cerbation and remission of clinical lesions. This course is variable and depends on the individual characteristics of each patient. First-line treatment typically involves the topical administration of corticosteroids. However, the therapeutic response is inconsistent in duration, with recurrences possible after variable intervals. This alternation between tissue repair processes and exacerbation of oral lesions can leave areas of altered mucosa that are more susceptible to complications. These complications usually develop over time and can range from mild to severe.

Frequent recurrences, the chronic course, and the necessity of constant adjustment and individualization of treatment require regular monitoring of OLP patients. Thus, patients diagnosed with oral lichen planus are monitored at varying intervals, depending on their response to treatment. Even in cases of complete remission, two follow-up appointments per year and the maintenance of rigorous oral hygiene are recommended^(12,13).

Complications of oral lichen planus and the risk of malignant transformation

As a chronic condition, oral lichen planus can lead to multiple complications. Some of these are manageable, while others can be very serious. Although the course of OLP is typically benign, it is classified by the World Health Organization (WHO) under the 1978 criteria as a condition with malignant potential^(14,15). The most common complication of OLP is oral candidiasis. This occurs partly due to altered local immune responses and, also, as a side effect of topical corticosteroid therapy. Periodic rinsing with chlorhexidine mouthwash (0.05-0.12%) is effective in preventing this complication⁽¹⁶⁾.

In some cases, after several years of progression, patients with OLP may experience a reduction in oral mucosa elasticity due to fibrosis. However, the most severe complication of oral lichen planus is the potential development of oral carcinoma. For this reason, it is crucial to eliminate any risk factors for oral cancer in the management of OLP patients. Additionally, the prevention or treatment of oral candidiasis is essential. For any suspicious lesion changes, a biopsy and histopathological examination are always recommended to rule out the early onset of carcinoma^(17,18).

The importance of an interdisciplinary approach to oral lichen planus

Although oral lichen planus primarily manifests in the oral mucosa, there are cases that require an interdisciplinary approach. This is partly due to the possibility of lichen planus manifesting simultaneously in different areas of the body with similar structures, such as the skin, genital or esophageal mucosa, and nails. Additionally, the association of oral lichen planus with certain systemic conditions such as diabetes, chronic hepatitis C, or autoimmune thyroiditis is well documented in the literature. It has been observed that the worsening of lichen planus oral lesions often coincides with the decompensation of coexisting systemic diseases.

Furthermore, in cases where chronic hepatitis C is present, oral lichen planus lesions tend to show a poor therapeutic response, and their long-term progression may be influenced by antiviral treatments. For this reason, a comprehensive evaluation of OLP patients is recommended to identify associated systemic diseases^(19,20).

Conclusions

Lichen planus is a relatively common condition affecting the oral mucosa. An interdisciplinary approach is necessary for extensive forms that involve simultaneous cutaneous or genital mucosal localization. Given the documented association with certain systemic conditions, it is important to include screening in the diagnostic protocol for OLP. As oral lichen planus is classified as a condition with malignant potential, regular patient monitoring is recommended, along with the elimination of local and systemic factors that may contribute to the risk of oral cancer. 

Autori pentru corespondenţă: Elena-Claudia Coculescu E-mail: elenacoculescu@ yahoo.com; Mihaela Tănase E-mail: mihaelatanase16@ yahoo.com

CONFLICT OF INTEREST: none declared.

FINANCIAL SUPPORT: none declared.

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