皮肤T细胞淋巴瘤表观遗传学研究进展

表观遗传学主要是研究在不改变DNA序列的情况下,发生的基因表达水平可遗传的变化,主要包括DNA甲基化、组蛋白修饰和非编码RNA调控.皮肤T细胞淋巴瘤是一组原发于皮肤的T淋巴细胞恶性增殖性疾病,蕈样肉芽肿和Sezary综合征是最常见的皮肤T细胞淋巴瘤.近年来研究表明,表观遗传学不仅在皮肤T细胞淋巴瘤的发生发展中起重要作用,而且可以通过改变表观遗传达到治疗皮肤T细胞淋巴瘤目的.     

Aneuploidy in cutaneous T-cell lymphoma

A new method is described which makes it possible using skin specimens to perform flow cytometric analysis of DNA content. DNA content analysis was performed on 28 skin specimens and 9 blood samples from 18 patients with mycosis fungoides and Sézary syndrome. The reproducibility was fair, with almost identical results in 6 cases (mycosis fungoides and Sézary syndrome) where two samples (skin specimens or blood samples) were taken 6 hours to 10 days apart. Hyperdiploidy was found in 7 of 11 skin specimens from patients with mycosis fungoides stage I with negative histology. In 13 skin specimens and 3 blood samples from patients with mycosis fungoides stages II and IV, abnormalities including hyperdiploidy, near-tetraploidy and near-hexaploidy were found in 8 of 13 skin specimens and in 2 of 3 blood samples. Four patients with Sézary syndrome were studied: 2 patients in remission showed normal DNA histograms (2 skin specimens, 3 blood samples) and 2 patients with active disease showed aneuploidy in the 2 skin specimens examined and in 1 of 3 blood samples. These studies demonstrate: 1) the importance of flow cytometry as a diagnostic tool for use on skin specimens in the early stages of mycosis fungoides where routine histology is non-diagnostic; 2) the diagnostic and prognostic aid of flow cytometry during the course of mycosis fungoides and Sézary syndrome in addition to the probability of measuring the effect of treatment.     

Infantile-onset cutaneous T-cell lymphoma

Background Mycosis fungoides (MF), the most common form of cutaneous T‐cell lymphoma (CTCL), is mainly a disease of the elderly. Objectives To review paediatric CTCL cases reported in the literature, with a focus on the time between onset of symptoms and establishment of a correct diagnosis. Methods A review of the literature was carried out and a case reported. Results A total of 254 cases of CTCL have been reported in children aged < 16 years, 13 cases (< 1% of all reported cases) in children below the age of 2 years, and only seven cases (including ours) during the first year of life. CTCL was most prevalent in children aged 10–12 years. The delay between age of onset and establishment of diagnosis was largest in the youngest age group (0–3 years), and declined steadily thereafter, thus reflecting the increasing likelihood that CTCL is considered in the differential diagnosis of skin disorders with increasing age of the patient. Conclusions The diagnosis of CTCL is frequently delayed in young children. It needs to be considered in chronic ‘eczematous’ skin lesions irrespective of the patient’s age, and including infants.     

Treatment of cutaneous T-cell lymphoma

Intensive treatment of cutaneous T-cell lymphoma with modalities directed only at skin manifestations appears to cure up to 40 per cent of patients with early, limited skin involvement. For patients with widely disseminated skin lesions, the dermatologist often must choose a treatment regimen with both cutaneous and systemic effects in order to provide effective long-term control. Although vigorous combined-modality therapy results in improved disease-free survival intervals, it also has significant associated morbidity. When compared with less intensive treatment regimens, it is not clear at this time whether such combined-modality therapy improves either the cure rate or overall survival intervals of patients with early disease. For this reason, the authors recommend a conservative treatment program initially for most patients unless there is clinical evidence that the patient has biologically aggressive disease.     

Pathogenesis of cutaneous T-cell lymphoma

Cutaneous T-cell lymphoma is a malignant disease whose behavior reflects its T-cell lineage. The biologic characteristics of the disease are understandable when viewed from a perspective of normal T-cell-skin interactions. Thus, it is of no surprise that this malignancy of helper T lymphocytes usually demonstrates a remarkable affinity for the skin at the outset and that, coincident with decreased dependence upon this unique environment, the extent and aggressiveness of disease increases. Although the inciting event responsible for the development of cutaneous T-cell lymphoma is unknown, a mechanism for local growth and distant expansion of malignant cells has been postulated in terms of IL-2-dependent and -independent growth phases. As our vision into the cellular and subcellular workings of this malignancy becomes more acute, specific therapeutic and preventive measures will emerge.     

Nail dystrophy in cutaneous T-cell lymphoma

A case is reported of cutaneous T-cell lymphoma in an elderly woman. Dystrophy of all 20 nails was caused by a lymphomatous infiltrate of the nail apparatus.     

Therapeutic advances in cutaneous T-cell lymphoma

A variety of novel therapeutic modalities have recently become available for patients with cutaneous T cell lymphoma (CTCL). In particular, with recent FDA approvals of the three new agents vorinostat (Zolinza), romidepsin (Istodax), and pralatrexate (Folotyn) CTCL treatment has been transformed. Here, we offer a brief overview of these agents and discuss their place in the spectrum of current therapies for CTCL.     

Treatment planning in cutaneous T-cell lymphoma

Effective long-term management of cutaneous T-cell lymphoma (CTCL) requires administration of skin-directed therapies such as topically applied nitrogen mustard or photochemotherapy to achieve a complete response in clinically early disease (patch and thin-plaque-phase mycosis fungoides, MF) and often the concomitant administration of well-tolerated drugs with systemic effects such as interferon alfa, bexarotene, methotrexate or extracorporeal photopheresis in more advanced, but not highly aggressive/nontransformed disease (thick plaque or tumor phase MF or erythrodermic CTCL). The author's approach is provided as a guide for dermatologists in private practice.     

种痘样水疱病样皮肤T细胞淋巴瘤

种痘样水疱病样皮肤T细胞淋巴瘤是近年来被逐渐认识到的一种与EB病毒相关的少见淋巴瘤,多见于儿童和青少年,主要累及面部和四肢,表现为丘疹、丘疱疹和水疱,随后出现坏死、溃疡、结痂,最后留下痘疮样瘢痕.本病临床表现独特,确诊主要依靠组织病理检查及免疫组化.目前尚无统一有效的治疗方案,报道的多数病例采用化疗,但疗效不一.     

Subcutaneous panniculitis-like T-cell cutaneous lymphoma

Subcutaneous panniculitis-like T cell lymphoma (SPTCL) is a rare cytotoxic T-cell lymphoma classified in the World Health Organization-European Organization for Research and Treatment of Cancer (WHO-EORTC) classification as a unique extranodal lymphoma with characteristic by T cell receptor (TCR) gene rearrangement. We report here a case of SPTCL in a 22 year-old woman who had presented with variably sized multiple nodules on both her legs. Initial differential diagnoses considered were panniculitis and lupus panniculitis. The histopathology showed a predominantly subcutaneous lobular infiltrate with atypical lymphocytes, karyorrhexis and rimming of adipocytes by lymphoid cells. Immunohistochemistry showed CD4-, CD8+, CD56- T-cell phenotype. Although TCR rearrangement studies were not done, the above T-cell phenotype and sparing of epidermis and dermis suggested the possibility of an SPTCL alpha/beta type. The patient received five cycles of a cyclophosphamide, doxorubicin, vincristine and prednisone (CHOP) regimen which resulted in the regression in her skin lesions and constitutional symptoms.     

Interferon in the treatment of cutaneous T-cell lymphoma

Interferons are polypeptides with a broad range of in vivo effects that have shown efficacy in cutaneous T-cell lymphoma (CTCL). Particularly useful is alfa interferon (IFN) which, as a single agent, has shown partial remission rates of > 50% and complete responses of > 20%. Side-effects are predictable, generally well tolerated and dose-related. The efficacy of IFN has increased with combination therapy without any significant increase in attendant side-effects. An update on the specifics of the different IFN subtypes, their inherent biologic activity, pharmacokinetics, efficacy and safety in CTCL is presented in this paper.     

Phototherapy for cutaneous T-cell lymphoma

Phototherapy has been utilized for decades in the treatment of various dermatologic conditions, including cutaneous T-cell lymphoma (CTCL). Currently, a number of light sources are available, and selection of the specific modality is based on a number of factors, the most important of which is disease stage. The efficacy of broadband ultraviolet B (UVB) is limited to the patch stage, while psoralen and ultraviolet A (PUVA) is capable of clearing plaques and, sometimes, early tumors. Narrowband UVB is also effective for early stages and has practical advantages over PUVA, but more studies are needed to more fully evaluate its role in CTCL. Long-wave ultraviolet A (UVA1) has likewise shown efficacy, supported by findings of apoptosis induction in UVA1-treated cells. Long-term remissions have been reported for PUVA, but in the majority of cases, maintenance therapy was necessary. Although beneficial as monotherapy for early stages of the disease, phototherapy is also a useful adjunct to other modalities such as interferons, retinoids and electron beam therapy. Studies are ongoing to refine protocols for combination therapy, with the goal of improving efficacy, while minimizing adverse effects.     

Posttransplant primary cutaneous T-cell lymphoma

A patient with posttransplant cutaneous lymphoma is described. Although most posttransplant lymphomas are of B-cell origin, this patient's lymphoma is a primary cutaneous lymphoma of T-cell origin. Another report exists of the first case of posttransplant primary cutaneous T-cell lymphoma localized to the lower extremities. Our patient's involvement was generalized with tumor nodules on the face and anterior chest. Reduced immune surveillance, chronic antigenic stimulation caused by transplant grafts, and the direct oncogenic effects of immunosuppressive drugs have all been suggested as mechanisms. Prompt recognition of this condition and initiation of appropriate therapy with reduction of high-dose immunosuppression can lead to better patient outcomes.     

Erythrodermic syringotropic cutaneous T-cell lymphoma

Syringotropic cutaneous T-cell lymphoma (CTCL) is a rare localized variant of CTCL, characterized histologically by eccrine gland and ductal hyperplasia surrounded by a dense syringotropic lymphocytic infiltrate. Previously reported only in men, we describe the first woman with syringotropic CTCL. Unusually, she presented with erythroderma, cutaneous nodules, poikilodermatous patches, widespread alopecia and lymphadenopathy.     

New insights into the applicability of T-cell receptor gamma gene rearrangement analysis in cutaneous T-cell lymphoma

BACKGROUND: Detection of clonal T-cell receptor (TCR) gamma gene rearrangement by polymerase chain reaction (PCR) based method is a marker for cutaneous T-cell lymphoma (CTCL) although it can be seen in some benign dermatoses. To determine the accuracy of histologic criteria alone as well as the adjuvant diagnostic role of TCR gene rearrangement for the diagnosis of CTCL, we studied 100 patients with cutaneous T-cell infiltrates by both histology and TCR gene rearrangement. METHODS: The histologic features of the 100 patients were first reviewed by two independent dermatopathologists and their confidence in the diagnosis of CTCL was assigned one of four levels. Then the specimens were analyzed for TCR gene rearrangement either on paraffin-embedded or fresh-frozen tissue by PCR/denaturing gradient gel electrophoresis (DGGE). RESULTS: The clonality was detected in 100% (15/15) diagnostic of, 84.6% (11/13) consistent with, 57.6% (19/33) suggestive of CTCL. In 9 cases TCR gene rearrangement was compared between formalin-fixed and fresh specimens of the same individual, but with different degrees of histologic confidence (no lower than suggestive). In all cases fresh specimens were positive. In 5 of the cases (2-diagnostic, 2-consistent, 1-suggestive) formalin-fixed specimens were positive as well, and in 4 cases (1-consistent, 3-suggestive) formalin-fixed specimens were negative. When TCR gene rearrangement was studied in eight cases on sequential biopsies from the same patient, the clonality was detected in only one or two biopsies in four cases in which the histologic confidence was low (suggestive or nondiagnostic). The TCR gene rearrangement study showed identical banding patterns in lesions from different clinical stages in most patients. However, we observed that in one case, oligoclonal-banding pattern was seen in initial biopsy with histopathologic consistent with CTCL, while monoclonal banding pattern in more advanced lesion. CONCLUSIONS: Our data have demonstrated that TCR gene rearrangement studies by PCR/DGGE are consistently positive regardless of tissue fixation (formalin-fixed, paraffin-embedded vs. fresh-frozen tissue) and biopsy site when the histologic degree of confidence is very high (diagnostic). So, it may be of less importance as an adjuvant to histopathologic diagnosis for the cases with diagnostic CTCL histology. However, TCR gene rearrangement studies are particularly important in earlier cases with less conclusive histology, which provides strong confirmatory evidence of an evolving CTCL. In these cases, multiple biopsies may be required to establish the diagnosis and analysis of fresh tissue is suggested to increases the sensitivity. Moreover, our observation also suggested that some CTCL might not be monoclonal de novo, but oligoclonal instead.     

Disseminated cutaneous herpes simplex infection in cutaneous T-cell lymphoma

We report two cases of Kaposi's varicelliform eruption that occurred in patients with cutaneous T-cell lymphoma. The purpose of this report is to emphasize that cutaneous T-cell lymphoma is among the chronic skin disorders that may predispose to cutaneous dissemination of viral infections.