Epidermal Langerhans' cell densities influence survival in mycosis fungoides and Sézary syndrome

Dendritic cell dysfunction in cancer: a mechanism for immunosuppression

Several reports have demonstrated that tumours are not intrinsically resistant to the immune response. However, neoplasias commonly fail to initiate and maintain adequate immunity. A number of factors have been implicated in causing the failure, including aberrant antigen processing by tumour cells, anergy or deletion of T cells, and recruitment of inhibitory/regulatory cell types. It has been suggested that dysfunction of dendritic cells (DC) induced by the tumour is one of the critical mechanisms to escape immune surveillance. As a minor subset of leucocytes, DC are the key APC for initiating immune responses. DC are poised at the boundaries of the periphery and the inner tissues, sampling antigens of diverse origin. Following their encounter with antigen or danger signals, DC migrate to lymph nodes, where they activate effector cells essential for tumour clearance. Although the DC system is highly heterogeneous, the differentiation and function of DC populations is largely regulated by exogenous factors. Malignancies appear to exploit this by producing a plethora of immunosuppressive factors capable of affecting DC, thus exerting systemic effects on immune function. This review examines recent findings on the effects of tumour-derived factors inducing DC dysfunction and in particular examines the findings on alteration of DC differentiation, maturation and longevity as a potent mechanism for immune suppression in cancer.

The New World Health Organization–European Organization for Research and Treatment of Cancer Classification of Cutaneous Lymphomas

The WHO-EORTC classification of cutaneous lymphomas is a good start to unifying nomenclature, a necessity before coherent consensus diagnoses can be made. There are three provisional diagnoses in this new classification that are not covered in detail in this review because they are rare diseases that still require further study for definitive classification. Much remains to be elucidated about cutaneous lymphomas, but understanding of the major entities within the new classification is an important first step in understanding these diverse diseases.

Long-term experience with low-dose interferon-alpha and PUVA in the management of early mycosis fungoides

OBJECTIVES

Combined high-dose Interferon-alpha and psoralen plus ultraviolet A irradiation (PUVA) have been reported to be effective in the treatment of early mycosis fungoides (MF); however, our study is the first controlled prospective study in the literature exploring the activity and tolerability of the combination with low dosages and evaluating further clinical outcome of early-MF patients.

METHODS

We carried out a multicentric prospective Phase II clinical study on 89 patients with early-stage IA to IIA MF treated for 14 months with low-dose IFN-alpha2b (6-18 MU/wk) and PUVA. Treatment success was analysed in terms of freedom from treatment failure.

RESULTS AND CONCLUSIONS

Complete remission (CR) was achieved in 84% and an overall response rate in 98% of cases: six-month CR was associated with a non-confluent skin infiltrate at histology (P = 0.044) and 14-month CR with high epidermal CD1a+ dendritic-cell density (P = 0.030). The combination protocol was successfully tolerated and the most common reason of 'failure' was related to relapse and not to toxicity. Sustained remissions were achieved in 20% of patients. High CD8+ lymphoid T-cell density was associated with a lower relapse rate (P = 0.002). We think that our combination therapy can be considered an alternative approach compared with other modalities. Good immunological host surveillance in the skin lesions seems to be an optimal basis for the therapeutic success.

What's new in the management of cutaneous T-cell lymphoma?

The aetiology and clinical management of primary cutaneous T-cell lymphoma (CTCL) and specifically of mycosis fungoides and Sezary syndrome are poorly defined. Interesting new insights into CTCL disease biology as well as a number of emerging of novel therapeutic interventions make this an increasingly interesting area for dermatologists and oncologists involved in the treatment of CTCL. This review article covers much of this new information including new drugs, such as denileukin diftitox (Ontak) a targeted cytotoxic biological agent, Bexarotene an RXR selective retinoid, anti-CD4 monoclonal antibodies (mAb), new cytotoxics agents and vaccines.

Prognostic factors in Sézary syndrome: a study of 28 patients

BACKGROUND

The new European Organization for Research and Treatment of Cancer classification considers Sézary syndrome (SS) among the aggressive epidermotropic cutaneous T-cell lymphomas (ECTLs). Recent technological advances have facilitated the diagnosis of this disease, but it remains practically incurable, with a median survival of about 2.5-5 years. Deaths are due in part to the iatrogenic effects of treatments, which suggests that the management of SS could be improved.

OBJECTIVES

Retrospectively to study the prognostic criteria related to disease progression.

METHODS

Thirty patients with SS were followed up in the Dermatology Department of the University Hospital in Nantes, France, between January 1989 and May 2000. The diagnosis of SS was based on at least three of the following criteria: erythroderma, histological evidence of ECTL, a level of 20% or more circulating Sézary cells, and loss of My7 antigen expression by basal cells of the epidermis. Two patients not seen again after the initial diagnosis were excluded from the statistical study.

RESULTS

The median disease-specific survival of the 28 patients was 64.55 +/- 10.11 months. The prognostic factors found in univariate analysis were age at diagnosis (P = 0.0109), interval before diagnosis (P = 0.0566), lactate dehydrogenase (LDH) level (P = 0.042) and presence of the Epstein-Barr virus (EBV) genome (BHLF in in situ hybridization) in skin (P = 0.0079). The prognostic factors found in multivariate analysis were age, interval before diagnosis and presence of the EBV genome in keratinocytes. A decreased number of Langerhans cells in the epidermis did not appear to be a prognostic factor.

CONCLUSIONS

Our study confirms the prognostic value of age and LDH level, and for the first time demonstrates the prognostic value of the identification of the EBV genome in the skin. This seems consistent with a marked immune deficit during severe forms of SS.

Cutaneous T-cell lymphomas: a review with emphasis on new treatment approaches

Primary cutaneous T-cell lymphomas represent a wide variety of non-Hodgkin lymphomas that are characterized by a distinct clinical presentation. Advanced molecular and biological techniques have enhanced the recognition of cutaneous T-cell lymphomas. The most common subtypes of cutaneous T-cell lymphomas are the epidermotropic variants mycosis fungoides and Sézary syndrome. At present, a stage-adjusted therapy is the best concept available, since early aggressive treatment options did not improve the prognosis of patients with cutaneous T-cell lymphomas. Accurate diagnostic and clinical assessment as well as identification of prognostic factors provides a helpful basis for treatment strategies. Current medical literature on diagnosis, prognosis, and treatment is reviewed with emphasis on new biologic response-modifying treatment options.

Primary cutaneous lymphomas: a review with current treatment options

Primary cutaneous T- and B-cell lymphomas are a heterogenous group of diseases with varied clinical presentations and prognosis. The use of new molecular, histological, and clinical criteria have enhanced the recognition of primary cutaneous T- and B-cell lymphomas. Compared to their nodal counterpart they have a different clinical behavior and therefore require a different treatment approach. Independent predictive factors identified clinically, histologically, and by immunopheno- and immunogenotyping are essential to assess the appropriate treatment for each subtype. The European Organization for Research and Treatment of Cancer (EORTC) Cutaneous Lymphoma Study Group provide a classification of cutaneous lymphomas taking into account of the histological and molecular features. Based on this classification we will provide a summary of the current medical literature in diagnosis, treatment, and prognosis for primary cutaneous lymphomas with emphasis on new treatment strategies.

Density of neoplastic lymphoid infiltrate, CD8+ T cells, and CD1a+ dendritic cells in mycosis fungoides

BACKGROUND/AIMS

CD8+ T cells and epidermal/dermal dendritic cells expressing CD1a are found among neoplastic CD4+ T cells in mycosis fungoides (MF) lesions. This study analysed the relation of CD8+ tumour infiltrating lymphocytes (TILs), CD1a+ epidermal Langerhan's cells (LCs), and dermal dendritic cells (DDCs) to clinicopathological parameters in 46 MF cases.

METHODS

Pretreatment diagnostic biopsy specimens of 46 MF cases were submitted to histological analysis and immunohistochemistry. Four histological grades were defined based on the density of the neoplastic infiltrate: grade 1 (mild superficial perivascular infiltrate), grade 2 (moderate superficial perivascular infiltrate with some tendency to confluence), grade 3 (pronounced superficial band-like infiltrate), and grade 4 (deep nodular infiltrate). Epidermotropism was scored as low, moderate, or high. Numbers of CD8+ T cells and of dermal and epidermal CD1a+ cells were scored as 1 (low), 2 (moderate), and 3 (high). Correlations between these parameters and clinical data (age, sex, clinical type of lesions, stage, response to treatment, and recurrence) were analysed by the chi(2) test.

RESULTS

Numbers of TILs and DDCs were associated with subepidermal infiltrates, being lower in less dense infiltrates, whereas there was no association between epidermal CD1a+ cells and the analysed parameters. Complete remission in treated patients was related to subepidermal infiltrates but not to TILs, LCs, or DDCs.

CONCLUSIONS

These results support the notion that CD8+ cells and dermal CD1a+ cells are active against tumour cells. MF with low numbers of TILs could represent an early stage of the disease, before TILs are activated against tumour specific antigens.

Primary cutaneous T-cell lymphoma: review and current concepts

PURPOSE

Primary cutaneous T-cell lymphomas (CTCLs) encompass a wide variety of lymphomas that are characterized by the localization of the malignant lymphocytes to the skin at presentation. Advances in molecular biologic techniques, including immunophenotyping and gene rearrangement studies to determine clonality, have led to more frequent diagnosis of CTCL as well as more consistent subclassification of these entities. However, there continues to be confusion in the classification, prognosis, and management of patients with CTCL. The purpose of this review is to present a summary of the diagnosis, prognosis, and treatment of CTCL, with specific emphasis on mycosis fungoides (MF) and Sézary syndrome (SS). We also present a detailed discussion of the entities that make up the differential diagnosis of CTCL.

DESIGN

We reviewed the medical literature on CTCL and other diseases that make up the differential diagnosis of CTCL.

RESULTS AND CONCLUSION

MF and SS are the most common forms of CTCL. The etiology of this disease is still unknown. Patients may go for months to years with skin abnormalities before being diagnosed. MF/SS is an indolent disease and patients with T1 disease have a normal life expectancy. Patients who undergo transformation to large-cell lymphoma (8% to 23% of patients) have a poor prognosis, with mean survival ranging from 2 to 19 months. Treatment for MF/SS continues to be palliative. There are many new therapies that are currently being investigated in clinical trials, and the DAB(389)IL-2 fusion protein was recently approved for the treatment of refractory MF/SS.

S100+ cell response to squamous cell carcinoma of the lip: inverse correlation with metastasis

Previous work has suggested a key role of dendritic cells in antineoplastic immunity. The course of mycosis fungoides and cancers of the lung, colon, thyroid and stomach has been associated with dendritic cell response to the primary tumor. However, this has not been reported for cutaneous or mucosal squamous cell carcinoma (SCC). Thirty-six cases of primary SCC of the lip mucosa or vermillion border, including nine cases with regional metastasis, were studied to investigate the relationship of dendritic cell density with age, tumor grade, mitotic rate, diameter, ulceration, depth of invasion, muscle invasion, tumor-infiltrating lymphocytes (TILs) and metastasis. Dendritic cells were identified using S100 immunohistochemistry, and their peritumor and intratumor density (peri-S100D and intra-S100D) were determined. The mean peri-S100D was 314 +/- 50/mm2. High peri-S100D was associated with lower rate of metastasis (P = 0.03), and no case with peri-S100D > 311/mm2 metastasized. Peri-S100D inversely correlated with depth of invasion (P = 0.04) and ulceration (P = 0.02), and positively associated with TILs (P = 0.02). The mean intra-S100D was 317 +/- 42/mm2. Intra-S100D did not quantitatively correlate with metastasis; however, no metastasis occurred when intra-S100D exceeded 515/mm2. Intra-S100D correlated with brisk TILs (P = 0.04). These results suggest a functional role of dendritic cells in the immune response to SCC. Peri-S100D may be a prognostic indicator.

Dendritic cells: therapeutic potentials

Dendritic cells (DCs) are leukocytes that are specialized to capture antigens and initiate T-cell-mediated immune responses. After capture of antigens, DCs, then in an immature stage, leave their tissue of residence and migrate through the lymph/blood into secondary lymphoid organs where they differentiate into mature cells. Because DCs can prime animals in the absence of any other adjuvant, they have been termed 'nature's adjuvant'. Large numbers of DCs can now be generated from circulating monocytes or from CD34 hematopoietic progenitors in response to GM-CSF in combination with either IL4 or TNF alpha. In mice, tumor antigen loaded DCs have been shown to prevent the development of tumors and even to induce the regression of established tumors. DCs therapy represents a very promising approach to the treatment of cancer and infectious diseases. Early studies indicate the existence of DC populations that can induce tolerance and may prove useful in organ transplantation.

Lack of correlation between DNA ploidy, Langerhans cell population and grading in oral squamous cell carcinoma

This study was undertaken to determine the inter-observer reproducibility of the invasive cell grading method on oral squamous cell carcinomas and to correlate this with the DNA ploidy status and Langerhans cell (LC) population. Fifty formalin-fixed paraffin-embedded blocks that contained both tumor and adjacent normal epithelium were randomly selected. DNA ploidy analysis was performed on a flow cytometer and the LC population was determined using an immunohistochemical technique with anti-S100 and anti-HLADR primary antibodies. The inter-observer correlation of the total malignancy score and individual morphologic features was highly significant. Thirty-two of the 50 tumors were graded as poorly differentiated and 18/50 as moderately differentiated. Thirteen of 25 poorly differentiated tumors had an aneuploid DNA content compared with 9/18 of the moderately differentiated group. No statistical differences in the LC counts between the poorly and moderately differentiated and aneuploid and diploid carcinomas were found. This study showed that the invasive cell grading method is reproducible but no correlation was found between the grading results and the ploidy status or LC count.

Immunophenotyping on simultaneously occurring plaques and tumours in mycosis fungoides and Sézary syndrome

Skin biopsy specimens from 15 patients with mycosis fungoides and Sézary syndrome, with simultaneously occurring plaques and tumours, were examined to assess phenotypic deviation. We focused on immunophenotypic differences between the two types of lesions with respect to the T-cell markers CD2, CD3, CD4, CD5 and CD8. In six patients (40%) loss of one or more T-cell markers occurred in at least one of the lesions. Three of the patients studied (20%) showed a difference in immunophenotype between plaques and tumours, with an additional loss of one of the T-cell markers in the tumours (respectively, CD5, CD2 and CD4). All three of these patients showed a larger number of blast cells in the tumour compared with the plaque. No correlation between this loss of antigenicity and the prognosis was observed. The results of this study show that different immunophenotypes can occur simultaneously in an individual patient. Furthermore, we were able to confirm a relationship between the number of intraepidermal CD1+ cells in plaque lesions and the prognosis.

Combined proliferating cell nuclear antigen and morphometric analysis in the diagnosis of cutaneous lymphoid infiltrates

AIMS

To evaluate the use of morphometry in the diagnosis of benign and malignant cutaneous lymphoid infiltrates; and to determine whether the sensitivity of detection of cutaneous T cell lymphoma (CTCL) could be improved by selectively measuring cells expressing proliferating cell nuclear antigen (PCNA).

METHODS

44 archival biopsy specimens were studied. These included cases of CTCL, non-specific chronic dermatitis, lichen planus and lupus erythematosus. PCNA was identified using a standard immunohistological technique. Reactive cells were identified using automatic colour discrimination, and the size and shape were determined interactively. Similar measurements were made on the total dermal lymphocyte population.

RESULTS

There was no significant difference between the proportions of PCNA reactive cells in any of the diseases studied. The PCNA positive lymphocytes in CTCL were larger than those in lupus erythematosus and lichen planus and were more irregular in shape than those in chronic dermatitis. Differences were also seen in the total lymphocyte population. Plotting cell size and shape(fcircle) for PCNA cells together allowed CTCL to be differentiated from the inflammatory disorders with a sensitivity of 80% and a specificity of 93%. This was better than could be achieved using measurements made on the total cell population.

CONCLUSIONS

This technique can be partly automated and could be useful in the differential diagnosis of cutaneous lymphoid infiltrates. The result are also of some interest in the further understanding of patterns of cell proliferation in skin associated lymphoid tissue.

Factor-XIIIa-expressing dermal dendrocytes in Kaposi's sarcoma

The histogenetic origin of Kaposi's sarcoma is a matter of controversy, with recent reports claiming it to derive from the factor-XIIIa-positive dermal dendrocyte rather than endothelial cells. We investigated the potential role of factor-XIIIa-positive dermal dendrocytes in the genesis of both classical (endemic) and immunosuppression-associated Kaposi's sarcoma. Thirteen cases of classical and 16 cases of immunosuppression (mostly AIDS)-associated Kaposi's sarcoma were immunostained with antibodies to factor XIIIa and to the blood-group antigen H, recognizing endothelial cells. Factor-XIIIa-positive cells were consistently antigen-H-negative and represented only a small percentage (usually less than 10%) of the proliferative cells. Their relative density tended to be decreased in immunosuppression-associated Kaposi's sarcoma when compared with that of the classical form. These results do not support the view that dermal dendrocytes may be the cells of origin of Kaposi's sarcoma; conversely, their decreased density in cases of immunosuppression-associated Kaposi's sarcoma could be related to immunosuppression and may account for more rapid tumour growth.