Letter: HLA and mycosis fungoides

Mycosis fungoides--analysis of the duration of disease stages in patients who progress and the time point of high-grade transformation

BACKGROUND

Mycosis fungoides (MF) is a low-grade malignant primary cutaneous T-cell lymphoma which, in its evolution, passes through five distinct stages (patch, plaque, and tumor stages, lymph node infiltration, and, finally, multiple organ infiltration). Furthermore, a blast transformation into a high-grade malignant lymphoma can occur. In order to better understand the dynamics of the disease and the prognostic implications in patients who progress, we studied the duration of each stage and the time at which blast transformation occurred.

METHODS

We reviewed the records of 48 MF patients who had been followed in the lymphoma clinic of the Department of Dermatology, University Hospital Zurich, Zurich, Switzerland for a median of 10 years. Forty-two cases were eligible for evaluation.

RESULTS

Our study showed that MF in patients who progress is a disease which, after an initial patch stage with an average duration of 7.2 years, a plaque stage lasting for an average of 2.3 years, and a tumor stage with an average duration of 1.8 years, leads to a stage of lymph node infiltration with an average duration of 0.6 years, internal organ infiltration lasting for an average of 0.5 years and, finally, a fatal outcome. Consequently, the overall average disease duration in progressing patients is 12.4 years. Blast transformation occurs in 85% of all cases in the tumor stage.

CONCLUSIONS

The course of progressing MF is chronic and advancing. The progression is initially slow and later accelerates. Important prognostic factors are the stage of disease and the presence of blast transformation. The prognosis is better in the early stage and when blast transformation is absent.

From inflammation to neoplasia: new concepts in the pathogenesis of cutaneous lymphomas

Mycosis fungoides is a clinicopathologic term which describes a neoplasm of cerebriform T lymphocytes that form plaques and tumors. We further suggest that mycosis fungoides arises in a background of chronic inflammation or as a response to chronic antigenic stimulation. Subsequently, a series of mutations results in the stepwise progression from eczematous patches, to plaques, tumors and eventual hematogenous dissemination. The pathogenetic process is driven by various, probably individually different, exogenous factors, e.g. environmental foreign antigens, bacterial superantigen, and/or endogenous factors, e.g. autocrine cytokine loops, CD40/CD40L and B7/CD28 interaction.

Mycosis fungoides: HLA class II associations among Ashkenazi and non-Ashkenazi Jewish patients

BACKGROUND

An immunogenetic mechanism has been suggested to play a role in the pathogenesis of mycosis fungoides (MF). While results of studies on HLA class I associations haveproved inconsistent, two previous studies showed that certain HLA class II alleles were significantly increased among North American caucasian patients with MF: HLA-DRB1*11 and DQB1*03.

OBJECTIVES

To investigate the possible HLA class I and class II associations with MF among Jewish patients.

METHODS

The patient group comprised 68 Jewish patients with MF: 38 Ashkenazi and 30 non-Ashkenazi. The control group comprised 252 healthy Jewish volunteers: 132 Ashkenazi and 120 non-Ashkenazi. Tissue typing for HLA class I (A and B) was performed using the National Institutes of Health microlymphocytotoxicity technique. DNA-based low-medium resolution analysis for DRB1* and DQB1* alleles was performed using polymerase chain reaction (PCR) amplification with sequence-specific primers. For those alleles found to have significantly increased frequency, high-resolution analysis was done by means of PCR sequence-specific oligotyping.

RESULTS

The allele frequency of HLA-DRB1*11 was found to be significantly increased but only among Ashkenazi patients with MF (30% vs. 19% in the controls; P = 0.034). High-resolution analysis for DRB1*11, not previously performed, suggested that its greater frequency is due to the increased number of Ashkenazi MF patients with the DRB1*1104 allele (P corrected = 0.036). Analysed together, DQB1*03 alleles (DQB1*0301-0304) had a significantly greater frequency in MF as a group as compared with controls (47% vs. 33%, P = 0.003). DQB1*0301 was demonstrated to be the specific allele associated with MF in Jewish patients (allele frequency of 36% vs. 23% in controls; P corrected = 0.0068), which was not the case for North American caucasian patients with MF. No greater frequencies of any of the HLA class I A or B antigens were found.

CONCLUSIONS

Our findings further demonstrate the 'universality' of MF HLA class II susceptibility alleles, i.e. HLA-DRB1*11 and HLA-DQB1*03, suggesting that HLA polymorphism is likely to be important in the pathogenesis of MF in Jewish patients, as it is in North American caucasian patients. Not previously reported is our finding that HLA-DRB1*1104 is the specific allele more prevalent among patients with MF. Our study also underscores some differences in HLA profiles between non-Jewish and Jewish patients with MF and between Ashkenazi and non-Ashkenazi Jewish patients, indicating the possibility of diverse HLA disease associations in populations with different genetic backgrounds. Our study provides further evidence for the lack of association between HLA class I and MF.

Cutaneous T-cell lymphomas: prognosis and quality-of-life issues

Cutaneous lymphomas (CL) include lymphocytic malignancies derived from B cells, T cells, or other cell types such as natural killer cells. Cutaneous T-cell lymphomas are the most common CL, especially mycosis fungoides, Sézary syndrome, and the spectrum of large-cell CD30(+) lymphoproliferative disorders. It is important to understand that these diseases have a much better prognosis than their nodal counterparts; therefore, treatment has to be stage adapted and palliative. Due to the anatomical localization, these lymphomas have significant impact on the quality of life of the patient.

Human leukocyte antigens in cutaneous T cell lymphoma

Mycosis fungoides (MF) and Sézary syndrome (SS) are malignant non-Hodgkin's lymphomas, characterized by the proliferation of helper type T lymphocytes with a predilection for the skin. Because of the similarities in cytologic, histologic, cytogenetic, immunologic, and functional aspects of the malignant cells, as well as overlapping clinical features, these disorders are currently classified as cutaneous T cell lymphoma (CTCL). Though the etiology of these disorders remains obscure, environmental factors as well as viral infection have been implicated. In this study, seventy-six white patients with CTCL were typed for human leukocyte antigen (HLA)-A, -B, and -C to assess genetic susceptibility as determined by the major histocompatibility complex. An increase in the frequency of B8 and Bw35 was seen in SS patients but not in MF patients.

Association of HLA-DR5 with mycosis fungoides

Mycosis fungoides (MF) and Sézary syndrome (SS) are uncommon neoplasms of the lymphoreticular system with distinct clinical, histologic, and immunologic features. Based on the thymus-derived nature of the neoplastic cells, MF and SS are both classified as cutaneous T-cell lymphoma. While substantially greater understanding of MF and SS has been made possible, the exact mechanism for the initiation of either disease is still unknown. The possible involvement of environmental factors as well as viral etiology, i.e., retroviruses, has been suggested. In order to investigate the possible role of HLA-associated variations in genetic susceptibility, 74 patients with histologically documented MF were typed for HLA-A, -B, and -C antigens. Half of these patients were also typed for HLA-DR antigens. An increase in DR5 was the only statistically significant deviation in HLA antigen frequencies in these patients (53% in MF as compared with 20% in controls). An increased frequency of HLA-DR5 has also been associated with scleroderma and juvenile rheumatoid arthritis both of which have immunologic alterations. Also HLA-DR5 has been associated with renal cell carcinoma and Kaposi's sarcoma. The association of MF with DR5 suggests that some individuals with the DR5 antigen may be at higher risk for virally initiated and/or neoplastic diseases possibly through an HLA-linked defect in the immune system.