Advances in diagnostics and treatment of cutaneous lymphoid hyperplasia

BACKGROUND: Cutaneous lymphoid hyperplasia is a reactive dermatosis characterized by the development of lymphocytic infiltration due to prolonged exposure to provoking factors with a tendency to spontaneous regression after elimination of antigenic stimulation without the development of systemic manifestations, sometimes having a difficult-to-distinguish similarity with B-cell lymphoma of the skin. Currently available diagnostic methods do not always allow to obtain an accurate result, and the arsenal of therapeutic agents does not sufficiently meet the criteria of effectiveness and safety.

AIMS: Diagnosis and therapy of benign lymphoplasia of the skin.

MATERIALS AND METHODS: The study included 57 patients who were observed at the V.A. Rakhmanov Clinic of Skin and Venereal Diseases of Sechenov University for skin lesions clinically similar to cutaneous lymphoid hyperplasia. Based on the results of histological, immunohistochemical and molecular genetic studies, the main study group was formed, which included patients with cutaneous lymphoid hyperplasia (n=35). After verification of the diagnosis, the expression of IgG4 in the lesions was studied, and the efficacy and safety of photodynamic therapy was evaluated both in the form of monotherapy by the method red light irradiation with a wavelength of 660±2 nm using the photosensitizer chlorin E6 once a week, and in combination with intraocular (0.5 ml/cm²) or intramuscular (2 ml each) injections of betamethasone suspension (Diprospan), carried out 1 time a week until complete cleansing of the skin.

RESULTS: Among 35 patients with cutaneous lymphoid hyperplasia, there were 14 men and 21 women aged 18 to 78 years (the average age was 42.7±2.8 years). IgG4+ was detected in 5 (17%) of 30 patients with cutaneous lymphoid hyperplasia (tattoo n=3, idiopathic n=2), as well as in 7 (78%) of 9 patients with confirmed B-lymphoma of the skin. Photodynamic therapy monotherapy (n=20) made it possible to achieve clinical remission in an average of 3–6 irradiation sessions, the combination of photodynamic therapy and betamethasone suspension in 15 patients with widespread and resistant to photodynamic therapy monotherapy rashes led to the clinical remission in 100% of patients after 7 photodynamic therapy sessions and 4 diprospan injections. Minor side effects did not require discontinuation of treatment.

CONCLUSIONS: Thus, the diagnosis of cutaneous lymphoid hyperplasia is made only on the basis of a comprehensive examination (clinical and anamnestic assessment, histological, immunohistochemical, molecular genetic studies), however, there remains a certain percentage of patients in whom the verification of cutaneous lymphoid hyperplasia is difficult and requires improved diagnostics. IgG4 can be regarded as an additional diagnostic marker in the differentiation of cutaneous lymphoid hyperplasia and B-cell lymphoma of the skin: the tendency to increase the level of IgG4 may indirectly indicate the malignancy of the lymphoproliferative process. photodynamic therapy has demonstrated high efficacy and safety in patients with cutaneous lymphoid hyperplasia, allowing to achieve completely clean skin both with monotherapy and in combination with diprospan for resistant and/or widespread rashes.