Detailed analysis of the T-cell lymphocytic infiltrate in penile lichen sclerosus: an immunohistochemical and molecular investigation

Lichen Sclerosus et Atrophicus With Histopathologic Features Mimicking Mycosis Fungoides: A Large Series of Cases Comparing Genital With Extragenital Lichen Sclerosus

Lichen sclerosus et atrophicus (LSA) is a chronic inflammatory dermatosis of unknown etiology involving the genital and/or extragenital area, showing histopathologically a characteristic homogeneization and sclerosis of the superficial collagen with variably dense lymphoid infiltrates. Intraepidermal lymphocytes may be observed, and in some cases may pose differential diagnostic problems with mycosis fungoides (MF). We studied the histopathologic features of 121 cases of LSA with dense lymphoid infiltrates (genital: 94; male:female: 93:1; age range: 2 to 87 y; median age: 11 y; extragenital: 27; male:female: 0.1:1; age range: 11 to 79 y; median age: 59 y), to better characterize the intraepidermal lymphoid infiltrate and to compare genital with extragenital cases. Epidermotropic lymphocytes mimicking the histopathologic features of MF were present in 93.6% of the genital specimens but none of the extragenital cases. Interestingly, typical features of LSA were mssing in 39.4% of genital LSA, and in a further 25.5% were present only focally. Immunohistochemical analyses showed a predominance of CD8+ T-lymphocytes within the epidermis. Molecular studies of the T-cell receptor genes revealed a monoclonal population of T-lymphocytes in nearly half of the cases. Our study shows that MF-like histopathologic features are extremely common in genital LSA but are never encountered in extragenital cases. A diagnosis of MF in the genital area should be made only upon compelling features, keeping in mind the frequent pseudolymphomatous aspects of LSA.

Study of Langerhans cells and T lymphocytes in vulvar lichen sclerosus lesions

BACKGROUND

The aetiology and pathogenesis of vulvar lichen sclerosus (LS), a chronic inflammatory disease, is not completely clear. It has been found that local cellular immune abnormalities play an important role in the immune mechanism of LS, mainly characterised by abnormal numbers of Langerhans cells in the epidermis and abnormal numbers of dermal T lymphocytes.

OBJECTIVE

To evaluate the densities of Langerhans cells and T-lymphocyte subpopulations in vulvar LS.

METHODS

The density of Langerhans cells in the epidermis, and CD3⁺ , CD4⁺ and CD8⁺ T cells in the dermis of seven early-stage and eight late-stage cases of vulvar LS were detected with direct immunofluorescence, and compared with 15 normal controls.

RESULTS

The density of Langerhans cells in the late-stage group was significantly higher than in the normal group (P = 0.001). The densities of CD3⁺ , CD4⁺ and CD8⁺ T lymphocytes in both the early- and late-stage (deeper dermis) groups were higher than in the normal group (P < 0.05). The ratio of CD4⁺ /CD8⁺ T lymphocytes in the early-stage and normal groups showed no significant difference (P = 0.151), while the late-stage (deeper dermis) groups decreased significantly compared with early-stage, late-stage (upper dermis) and normal groups (P < 0.001).

CONCLUSION

The densities of Langerhans cells, CD3⁺ , CD4⁺ and CD8⁺ T cells, and the ratio of CD4⁺ /CD8⁺ T lymphocytes were different in different stages of LS, which supports the important role of cellular immunity in mechanisms of LS.

Defining the mimics and clinico-histological diagnosis criteria for mycosis fungoides to minimize misdiagnosis

Background

Mycosis fungoides (MF) is a significant diagnostic challenge; it has various differential diagnosis especially at an early stage. Our aim was to describe mimics of MF clinically and histologically, and to define significant diagnostic criteria of the disease.

Methods

This was a retro-prospective cohort of 370 patients in whom the diagnosis of MF was suspected clinically.

Results

MF was histologically confirmed in 15.4% of cases and rejected in 84.5%. Other identified histologically diagnosis were eczema, psoriasis; nonspecific dermatitis, lichen, lupus; pseudolymphoma, parapsoriasis and toxidermia. 4 patients with palmoplantar MF were wrongly treated as eczema, and 10 patients with psoriasiform MF were initially treated as psoriasis. We also described the clinical, histological and immunohistochemistry diagnostic criteria for distinguishing MF from benign dermatosis.

Conclusions

Misdiagnosis of MF was a real problem for this study, because it shared common clinical and histological characteristics with other inflammatory diseases like eczema and psoriasis. Therefore, defining significant clinico-histological diagnosis criteria of MF would be of great help and would increase the accuracy of the diagnosis.

Selected Inflammatory Imitators of Mycosis Fungoides: Histologic Features and Utility of Ancillary Studies

Mycosis fungoides is the most common primary cutaneous lymphoma; however, it remains a significant diagnostic challenge, in part because of the overlap with several inflammatory dermatoses. Despite advances in immunohistochemistry and molecular diagnostics, false-positive, false-negative, and indeterminate diagnoses are not uncommon. In most cases, the overall balance of morphologic, immunophenotypic, and genetic features must be considered carefully because there are few sensitive and specific clues to the diagnosis. Moreover, an appropriate clinical presentation is essential to the diagnosis and helps to favor or exclude inflammatory/reactive processes. Herein, we discuss 3 important inflammatory dermatoses that may closely simulate mycosis fungoides, and we review the use of ancillary studies in these challenging cases.

Differential gene hypermethylation in genital lichen sclerosus and cancer: a comparative study

AIMS

Lichen sclerosus (LS) is a chronic inflammatory disease of the genital skin of unknown aetiology. The role of LS in penile squamous cell carcinogenesis is not well characterized. HPV has been implicated in both, as have epigenetic changes. The presence of HPV and hypermethylation of the MGMT, p16, RASSF1, RASSF2, TSLC1 and TSP1 genes were studied in penile LS; MGMT, RASSF2 and TSLC1 hypermethylation in penile cancer and TSLC1 hypermethylation in vulvar LS and cancer extends previous results reported by our group.

METHODS AND RESULTS

Thirty-seven HPV genotypes and hypermethylation were evaluated by PCR/reverse-line-blot and methylation-specific PCR respectively, in 27 preputial LS, 24 penile SCC, 30 vulvar SCC, 21 vulvar LS and 22 normal skin cases. HPV66 was present in 3.7% of penile LS cases, and p16 and RASSF2 hypermethylation were more frequent in penile cancer than in penile LS. p16, RASSF1, RASSF2 and TSP1 hypermethylation were similar in penile and vulvar LS.

CONCLUSIONS

Gene hypermethylation is a common event in penile LS, and occurs approximately as frequently as in vulvar LS. Certain genes can be hypermethylated as an early or late event in LS or cancer, respectively. This suggests a possible sequential role for these alterations in the transition from benign to malignant lesions.

Lichen sclerosus

Lichen sclerosus (LS) is an inflammatory skin disease predominantly affecting the anogenital region. If untreated, progressive sclerosis results in scarring with distortion of the normal architecture. LS occurs more commonly in women than men but may occur in all age groups, including adolescents and prepubertal children. Its exact prevalence is unknown, but estimates range from 1:60 to 1:1000. In this article, LS is discussed in detail with respect to disease management in adults and children, risk of malignancy, and association with other diseases.

Characteristics of circulating T cell receptor gamma-delta T cells from individuals chronically infected with hepatitis B virus (HBV): an association between V(delta)2 subtype and chronic HBV infection

BACKGROUND

To date, few studies have been conducted to determine whether T cell receptor (TCR) gammadelta T cells are involved in hepatitis B virus (HBV) infection. This study was performed to assess the quantity and immune function of TCRgammadelta T cells in the blood of patients with chronic HBV infection and to analyze the relationship between proportions of TCRgammadelta T cells and both proportions of other immune cells and clinical parameters.

METHODS

Flow cytometry was used to detect the proportions of TCRgammadelta T cells and other immune cells in the peripheral blood of 46 asymptomatic carriers (AsCs) of HBV, 95 patients with chronic hepatitis B (CHB), and 29 healthy donors (HDs). The immune functions of TCRgammadelta T cells from 5 AsCs, 6 patients with CHB, and 5 HDs were assessed by cytokine secretion and cytotoxity assays.

RESULTS

The difference in the proportion of the V(delta)2 T cell subtype between HDs and patients was significant. For the patients, the proportion of V(delta)2 T cells was negatively correlated with alanine aminotransferase, aspartate aminotransferase, and total bilirubin levels. The differences in interferon (IFN)-gamma secretion and cytotoxicity between patients and HDs were significant.

CONCLUSIONS

The proportion of circulating V(delta)2 T cells was significantly decreased in patients with chronic HBV infection, and this was accompanied by a strong immune response in the liver. IFN-gamma secretion and TCRgammadelta T cell cytotoxicity was lower in patients than in HDs.

High prevalence of concomitant anogenital lichen sclerosus and extragenital psoriasis in adult women

OBJECTIVE

To analyze the prevalence of lichen sclerosus and psoriasis in gynecologic patients.

METHODS

The prevalence of lichen sclerosus and psoriasis individually, as well as the prevalence of both diseases in the same patient, was evaluated among 2,800 women attending a primary care gynecology practice for annual routine gynecologic examinations. The incidence of lichen sclerosus (new diagnosis of lichen sclerosus per year/population at risk) was calculated for the last 5 years.

RESULTS

Two hundred (7.1%) women had a biopsy-proven anogenital lichen sclerosus, and 57 women (2%) had an extragenital psoriasis vulgaris. Fifteen women had both diseases (0.5%). The prevalence of psoriasis in lichen sclerosus patients was 7.5% (15 of 200; 95% confidence interval 4.3-12.1%) compared with 1.6% (42 of 2,600) in the non-lichen sclerosus patient group. Lichen sclerosus was diagnosed in 13 of 15 psoriasis patients at an average of 19.5 years after the diagnosis of psoriasis at the age of 48 years (range 30-70 years). The incidence rates of lichen sclerosus for the last 5 years were 0.5% in 2002, 0.7% in 2003 and 2004, 1.9% in 2005, and 1.8% in 2006.

CONCLUSION

The prevalence of psoriasis in lichen sclerosus patients (7.5%) is higher than in the general population and among the non-lichen sclerosus patients in this practice (1.6%). This association may result from a similar immune dysregulation in these women.

LEVEL OF EVIDENCE

II.