T-cell receptor gene rearrangement in regressing atypical histiocytosis

A case of regressing atypical histiocytosis having characteristic clinical and light microscopic findings was studied immunologically for immunoglobulin and T-cell receptor gene rearrangement and for DNA ploidy analysis. Immunologic phenotyping and rearrangement of T-cell receptor Beta- and gamma-chain genes indicated that this primary cutaneous neoplasm, previously considered "histiocytic" in origin, is most probably of T-cell lineage.     

皮肤T细胞淋巴瘤的T细胞受体基因克隆性重排

目的 研究皮肤T细胞淋巴瘤（CTCL）早期诊断。方法 利用PCR方法，设计PCRVγ1-8,Vγ9,Jγ1/γ2特异引物，分析24例各类型CTCL，2例可疑CTCL及4例非特异性红皮病患者的33份示TCRVγ1-8,37份示Vγ9呈MCGR，BCGR或OCGR，尤其是13例早期蕈样肉芽肿，2例可疑CTCL和4例非特异性红皮病均呈TCRγ-GR克隆性扩增带，6例炎性病变标本示TCRγ-GR克隆性，提示他们为“克隆性皮炎”，需长期随访。结论 用PCR发现早期CTCL的PCRγ-GR克隆性，为诊断提供依据。     

Nasal-type T/natural killer cell angiocentric lymphoma, Epstein-Barr virus-associated, and showing clonal T-cell receptor gamma gene rearrangement

Nasal-type T/natural killer (NK) cell lymphoma, which often shows an angiocentric growth pattern, is a distinct clinicopathological entity highly associated with the Epstein-Barr virus (EBV). This tumour has a characteristic immunophenotype, whereas the cytological spectrum is broad. It is known that a clonal T-cell receptor (TCR) gene rearrangement is not found in this tumour. However, it is still unresolved as to whether the finding of a clonal TCR gene rearrangement excludes the diagnosis of nasal-type T/NK cell lymphoma. We describe a case of nasal-type T/NK cell angiocentric lymphoma, EBV-associated, and showing clonal TCR gamma gene rearrangement. The patient died of sepsis 5 months after diagnosis in spite of aggressive chemotherapy.     

Long-term implications of T-cell receptor gene rearrangement analysis by Southern blot in patients with cutaneous T-cell lymphoma

BACKGROUND: T-cell clonality analysis by Southern blot (TSB) in skin biopsy specimens suggestive of mycosis fungoides may be helpful in confirming the diagnosis of a cutaneous lymphoma. However, there are no data available regarding the long-term prognostic implication of such results. OBJECTIVES: We sought to determine the long-term prognostic significance of TSB results from skin biopsy specimens of patients with mycosis fungoides. METHODS: We reviewed the records from the Cleveland Clinic Foundation and Northwestern University Medical Center for cases of biopsy-proven mycosis fungoides with results available for skin biopsy TSB from 1987 to 1990. RESULTS: The detection of clonality by TSB correlates with a higher TNM stage (median stage for positive TSB, IIb vs negative TSB, Ib; P <.05), but not with age at presentation (62 vs 59 years) or duration of disease before presentation (6.2 vs 5.9 years). Although the long-term survival was not significantly different between the 2 groups, there was a trend for patients with positive TSB to die earlier (5-year survival of 67% vs 87%). Disease progression did not correlate with TSB results. Higher clonality rates were noted among patients with biopsy specimens showing a denser lymphoid infiltrate and a higher grade of cytologic atypia. CONCLUSIONS: Detection of clonality with TSB requires a significant clonal burden. Although clonality can be detected in patients with patches and plaques (T1 and T2) most cases with positive results were obtained from patients with advanced disease (T3 and T4). In our experience, detection of clonality by TSB does not correlate with disease progression and does not carry long-term prognostic implications.     

PCR-heteroduplex analysis of T-cell receptor gamma gene rearrangement in paraffin-embedded skin biopsies

We developed a rapid, simple, and sensitive method for the detection of T-cell receptor-gamma (TCRgamma) gene rearrangements in paraffin-embedded skin biopsies. Available techniques often require either fresh tissue, several primer pairs, nested amplifications, or specialized electrophoresis steps such as denaturing gradient gel electrophoresis. Our method is based on heteroduplex analysis of polymerase chain reaction (PCR) products of the TCRgamma in a nondenaturing modified polyacrylamide gel using a single pair of primers and is adapted for paraffin-embedded tissue. When tested against Southern blot analysis, the PCR results correlated in 8 of 9 cases. Six mature cutaneous B-cell lymphomas and 29 inflammatory skin disorders all resulted in a polyclonal amplification pattern. When analyzing 3-mm or 4-mm punch biopsies of 51 cases of cutaneous T-cell lymphoma, 37 (72.5%) showed a clonal rearrangement with this technique. For 7 cases of patch stage mycosis fungoides, frozen tissue and formalin-fixed and paraffin-embedded tissue was available, and in 5 of 7 cases (71%), the results in frozen and paraffin-embedded tissue were concordant. One case showed a clonal pattern in frozen tissue but not in paraffin-embedded tissue, and one case was polyclonal in frozen tissue but monoclonal in paraffin-embedded tissue. Using serial dilutions of DNA from a T-cell ALL in a polyclonal background (tonsil), we established a sensitivity of 0.5%. Heteroduplex PCR of the TCRgamma is a rapid, sensitive, and inexpensive screening procedure as well as a useful adjunct to histologic analysis and immunophenotyping of cutaneous T-cell proliferations.     

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.     

Granulomatous slack skin: clonal rearrangement of the T-cell receptor beta gene is evidence for the lymphoproliferative nature of a cutaneous elastolytic disorder

Granulomatous slack skin (GSS) is characterized by the slow evolution of bulky, erythematous skin folds that have a granulomatous histology, and show destruction of dermal elastic tissue. Several cases have been putatively associated with Hodgkin's disease, and histologic similarities to mycosis fungoides have also been noted. We examined tissue from 3 cases of GSS to determine whether the condition was inflammatory or lymphoproliferative in nature. We found an abnormal, monomorphous T-helper cell immunophenotype, and in all 3 cases, clonal rearrangement of the T-cell receptor beta gene. We conclude that GSS is an indolent cutaneous T-cell lymphoma associated with granulomatous inflammation that mediates elastolysis, producing a distinctive clinical appearance.     

T-cell receptor gene rearrangement studies as a diagnostic tool in lymphoproliferative skin diseases

Abstract The growth of our knowledge in T-cell biology, in particular the molecular biology of the T-cell receptor (TCR). has provided a means to molecularly characterize lymphoproliferative diseases of the skin based on the presence or absence of a clonal population of T lymphocytes. TCR gene rearrangement studies, by Southern blot analysis, have aided the investigative dermatologist in gaining insights into the pathogenesis and clonal evolution of lymphoproliferative skin diseases. In addition, the application of TCR gene rearrangement studies as a diagnostic aid in the evaluation of lymphoproliferative skin diseases has been introduced into clinical dermatology. Despite its enormous research value. TCR gene rearrangement studies presently have limited applications as an independent diagnostic tool. However, as our knowledge and experience grows and as the application of new techniques provides us with greater detection sensitivity and specificity, the diagnostic utility of TCR gene rearrangement studies will be enhanced.     

Detection of clonal rearrangement of T-cell receptor genes in the diagnosis of primary cutaneous CD30 lymphoproliferative disorders

BACKGROUND: Detection of clonality has been reported to be a helpful tool in the diagnosis of cutaneous lymphomas. Monoclonal rearrangement of T-cell receptor genes (TCR) was reported in fresh frozen tissue of lymphomatoid papulosis (LyP) and primary cutaneous anaplastic large-cell lymphoma (ALCL), but the diagnostic value of T-cell clonality in formalin-fixed, paraffin-embedded biopsies has so far not been assessed. METHODS: Detection of clonal rearrangement of TCRgamma genes by highly sensitive polymerase chain reaction-based automated high-resolution fragment analysis (AHRFA) in archival LyP (n = 18) and ALCL (n = 17) tissue. RESULTS: Detection of clonality differed significantly among the histologic forms of LyP as well as between LyP and ALCL with clonality found in none of the 10 biopsies of LyP type A and B, in 4/8 (50%) of the LyP type C specimens, and in 11/17 (65%) of ALCL cases. CONCLUSIONS: T-cell clonality can only be found in a minority (four of 18; 22%) of archival LyP specimens, even when employing a highly sensitive detection method and is thus of limited diagnostic value. Final diagnosis of LyP has to be based mainly on clinical, histologic, and immunohistochemical findings rather than on results of clonality studies.     

Diagnostic value of T-cell receptor beta gene rearrangement analysis on peripheral blood lymphocytes of patients with erythroderma.

Differentiation between Sézary's syndrome (SS) and benign forms of erythroderma may be extremely difficult. In this study T-cell receptor beta (TCR beta) gene rearrangement analysis was performed on peripheral blood lymphocytes (PBL) from 32 patients with erythroderma, including 10 patients with SS, three patients with another type of cutaneous T-cell lymphoma, and 19 patients with a benign form of erythroderma. The aim of this study was to define the sensitivity and specificity of this technique in the diagnosis of SS. Clonal TCR beta gene rearrangements were found in eight of 10 patients with SS, one T-CLL patient, one of two patients with erythrodermic mycosis fungoides, and only one of 19 patients from the benign group. In the two "false-negative" cases of SS clonal TCR beta gene rearrangements were detected in PBL obtained during follow-up. The results indicate that TCR beta gene rearrangement analysis on PBL is a sensitive and highly specific technique, that may contribute significantly to the differential diagnosis of patients with erythroderma. However, because both "false-positive" and "false-negative" results may occur, the results of gene-rearrangement analysis should always be considered in conjunction with clinical, histologic, and immunophenotypical data.     

TCRgamma-chain gene rearrangement by PCR-based GeneScan: diagnostic accuracy improvement and clonal heterogeneity analysis in multiple cutaneous T-cell lymphoma samples

Cutaneous T-cell lymphomas are a heterogeneous group of lymphomas where the tumor population emerges within a multiple subclone pattern ("clonal heterogeneity"). PCR analysis has been shown to be useful in the diagnosis of mycosis fungoides (MF) and Sézary Syndrome (SS). Focusing the attention on clonal heterogeneity, the efficacy of the multiplex/heteroduplex (HD) PCR and the GeneScan (GS) capillary electrophoresis analysis was compared in the early diagnosis of MF/SS, using a multiple sample approach. Indeed, GS demonstrated TCRgamma gene rearrangement (GR) in all the 57 SS (100%) and in 123/146 (84%) of the MF samples, whereas the multiplex/HD PCR was less sensitive. An increase in clonality was observed in connection with both a worsening of the cutaneous disease (79% T1/T2; 100% T3/T4) and an increase in the histopathological score (HS < 5, 76%; HS > or = 5, 94%). Clonal heterogeneity with adjunctive reproducible skin TCRgamma-GRs was also observed. "Clonal instability," with different GRs, was present in a small percentage of patients. Therefore, it can be concluded that GS analysis in TCRgamma-GR is able to improve diagnosis in MF/SS patients and the multiple sample approach is helpful for a correct interpretation of clonal patterns in skin lesions, especially in early-stage MF and in SS skin/blood samples.     

Detection of clonal T-cell receptor gene rearrangements in the peripheral blood of patients with mycosis fungoides/Sezary syndrome

Involvement of the peripheral blood in mycosis fungoides/Sezary syndrome (MF/SS) has a significant impact upon prognosis, but it is often difficult to distinguish circulating cells of MF/SS from atypical reactive lymphocytes. We compared the standard morphologic method of identifying leukemic cells, the Sezary preparation, to a genotypic method using Southern blot analysis of T-cell receptor gene rearrangements in concurrent blood samples. We studied 26 MF/SS patients, five of them in remission, together with five controls from cases of various non-MF/SS skin diseases. Six of 26 MF/SS patients had morphologically atypical circulating leukocytes (3%, 4%, 5%, 14%, 16%, 19%). Seven of 26 MF/SS patients had clonal T-cell receptor gene rearrangements, including the four patients with the greatest percentages of atypical cells and three patients lacking atypical cells. Six of seven patients had skin disease at the time of sampling, including three with erythroderma, two with generalized thick plaques, and one with generalized patches, while one patient was in clinical remission. All five controls lacked morphologic and genotypic evidence of atypical or clonal T-cells. Relative to genotyping, in our series the Sezary preparation was less sensitive and less specific. There were three apparent false negative results in the Sezary preparations, and two potential false positive (patients with 3% and 4% atypical leukocytes); however, there was agreement between the two techniques in most cases. We conclude that gene rearrangement studies may provide an effective test with which to assess the peripheral blood of MF/SS patients.     

Southern blot analysis of clonal rearrangements of T-cell receptor gene in plaque lesion of mycosis fungoides

T-cell populations of 22 plaque lesions from seven mycosis fungoides patients were studied for clonal rearrangement of the beta chain of the T-cell receptor (T beta) gene. All plaque lesions employed in this study showed clinically similar appearance. Histologically, all the biopsy specimens showed epidermotropism and the dermal infiltration of mononuclear cells including atypical cells. Histochemically, the majority of the infiltrated cells had surface markers of helper T cells. DNA extracted from skin lesions, peripheral lymphocytes, and lymph nodes revealed that the monoclonal expansion of T cells was different among patients and lesions. DNA extracted from the two skin lesions of case 1 revealed a clonal expansion of T cells. The rearranged bands persisted for about 1 year. In contrast, all lesions from cases 3-7 showed no rearranged band. Interestingly, three lesions from case 2 showed mixed type results, i.e., the monoclonal expansion of T cells was detected in one lesion but not in the other two lesions. Time course study of case 2 revealed that the same rearranged band became detectable in all three skin lesions and a lymph node about 1 year later. These results suggest that in plaque lesions of mycosis fungoides, there are various stages of detectable monoclonality of infiltrating cells, although the clinical appearance of the plaques was similar, and that the variety of monoclonality may reflect the long clinical course of this disease.     

T-cell receptor gene analysis in cutaneous T-cell lymphomas

An essential property of the immune system is its ability to generate diverse antibody and T-cell mediated responses to virtually any potential foreign particle, The basic molecular mechanisms responsible for producing this extensive diversity have now been elucidated. Each T cell expresses a unique membrane hound T-cell antigen receptor (TCR) which combines with specific antigenic peptides and major histocompatibility complex molecules. The characterization of TCR usage now represents a focal point for many studies of inflammatory and neoplastic disorders. Such studies are helping to clarify the pathogenesis of T-cell mediated diseases and provide the basis for the development of specific therapies. This paper will review several techniques used to identify neoplastic T-cell clones in cutaneous T-cell lymphoma. Similar methods may be used to analyse TCR gene usage in cutaneous inflammatory dermatoses.