Linfoma cutáneo primario difuso de células grandes-tipo pierna con regresión espontánea

Primary cutaneous diffuse large B-cell lymphoma, leg type (PCLBCL LT) accounts for approximately 20% of all primary cutaneous B-cell lymphomas and tends to present as infiltrated nodules, tumors, and plaques on the legs in the elderly. Unlike other primary cutaneous large B-cell lymphomas, it has a poor prognosis and tends to require treatment with systemic chemotherapy.We present the case of an 82-year-old patient with a 1-year history of nodules and plaques on her right leg. Biopsy led to a diagnosis of PCLBCL LT and the lesions resolved without treatment within 1 month of the first visit. This is an atypical course of PCLBCL LT and we believe that it is the first such case to be reported in the literature.     

The applicability of the new WHO-EORTC classification of primary cutaneous lymphomas to a single referral center

Recent years have witnessed differences between the World Health Organization (WHO) and the European Organization for Research and Treatment of Cancer (EORTC) classification systems of primary cutaneous lymphomas (PCLs). Recently, a joint WHO-EORTC classification system for PCLs has been reached. This study was performed to assess the applicability of this new classification to a single referral center. All new PCL cases, excluding mycosis fungoides and Sezary syndrome, who were referred from 1999 to 2005 were included. The histological, immunohistochemical stainings and molecular studies were reviewed, and additional stains were performed as needed. The cases were then reclassified according to the WHO-EORTC classifications. The clinical files were also studied, and the patients were followed up clinically. There were 43 new non-mycosis fungoides/Sezary syndrome PCLs, including 29 B-cell lymphomas of which 14 were follicle center lymphoma, 10 marginal zone lymphoma, 4 diffuse large-B-cell lymphoma, leg type, and 1 diffuse large-B-cell lymphoma, other. The 14 T-cell lymphomas included 5 cases of lymphomatoid papulosis, 2 CD30+ anaplastic large-cell lymphomas, 1 NK/T-cell lymphoma, and 6 peripheral T-cell lymphomas, unspecified. Of the 6 "unspecified" T-cell lymphomas, 3 were CD4+ small/medium-sized pleomorphic T-cell lymphoma, which is considered currently a provisional entity under the unspecified T-cell category. The remaining 3 cases could not be classified beyond the unspecified T-cell category, of which 2 cases had an aggressive course. The new WHO-EORTC classification is applicable to most non-mycosis fungoides/Sezary syndrome PCL cases, especially the B-cell lymphomas. However, there is still a substantial subset of T-cell PCLs which cannot be classified beyond the unspecified peripheral T-cell category, some of which may have an aggressive course.     

Comparative genomic hybridization analysis of cutaneous large B-cell lymphomas

The aim of the present study was to identify genetic aberrations in a series of patients with cutaneous large B-cell lymphoma (LBCL) using comparative genomic hybridization (CGH). Eighteen consecutive patients with primary (13 patients) (PCLBCL) and secondary (five patients) (SCLBCL) cutaneous large B-cell lymphoma were included in the study. Nine cases corresponded to PCLBCL leg type and four cases primary cutaneous follicle centre-cell lymphoma (PCFCL). Chromosomal imbalances (CIs) were detected in 14 of 18 samples (77.8%). All of nine cases with PCLBCL leg type and two of four cases with PCFCL showed CIs (100% and 50%, respectively). Regarding SCLBCL, in three of five cases (60%), CIs were detected. The most frequently detected gains involved 2q, 5q, 3 and 7q and amplifications affected 18, 12 and 13. Frequent losses were found in 17p. In PCLBCL leg type, the most frequent gains involved 2q and 7q, amplifications were localized in chromosomes 12, 13 and 18 and losses affected chromosomes 17p and 19. In PCFCL, gains located in 3q, 4 and 7q were found. Our study seems to confirm clear-cut differences between primary cutaneous LBCL and nodal diffuse LBCL, and it suggests the presence of genotypic differences between cases of PCLBCL leg type and cases of PCFCL.     

The applicability and prognostic value of the new TNM classification system for primary cutaneous lymphomas other than mycosis fungoides and Sézary syndrome: results on a large cohort of primary cutaneous B-cell lymphomas and comparison with the system used by the Dutch Cutaneous Lymphoma Group

BACKGROUND: Recently, a consensus proposal was published for a TNM classification system for all primary cutaneous lymphomas other than mycosis fungoides and Sézary syndrome, meant to document extent of disease in a consistent manner. The applicability and the prognostic significance of this system have not been investigated thus far. OBJECTIVES: To test the applicability and prognostic relevance of the proposed TNM classification system on a cohort of primary cutaneous B-cell lymphomas (CBCL). METHODS: The study group included 71 primary cutaneous marginal zone lymphomas (PCMZL), 171 primary cutaneous follicle centre lymphomas (PCFCL) and 58 primary cutaneous diffuse large B-cell lymphomas, leg type (PCLBCL, LT). As only patients with primary cutaneous lymphoma were included (T1-3, N0M0), only the T-rating was scored. The results were compared with the scoring as applied by the Dutch Cutaneous Lymphoma Group. RESULTS: The system was easily applicable to all cases. In PCMZL and PCFCL no correlation was found between T-score and survival (5-year disease-specific survival: T1, 100% and 98%; T2, 94% and 93%; T3, 100% and 88%, respectively). In PCLBCL, LT there was a clear, although statistically not significant, association between increasing T-score and reduced survival (5-year disease-specific survival: T1, 75%; T2, 49%; T3, 0%; P = 0.077). Comparing the TNM system with the Dutch Cutaneous Lymphoma Group system, there was a discrepancy in the classification of 20 cases. CONCLUSIONS: The new TNM system is a useful tool to document disease extent in patients with CBCL and provides prognostic information in the group of patients with PCLBCL, LT.     

Primary cutaneous diffuse large B-cell lymphoma of the leg according to the new WHO-EORTC classification. Two cases

Primary cutaneous lymphomas are a heterogeneous group of lymphoproliferative disorders characterized by skin involvement with no evidence of systemic disease at the time of diagnosis. Their clinical behavior is generally indolent, and only occasionally is the development of extracutaneous disease observed. Since the 1980s, primary cutaneous B-cell lymphomas have been considered a specific group of lymphomas, differentiated from both T-cell lymphomas and from secondary cutaneous B-cell lymphomas. Both the EORTC and the WHO have proposed alternative classifications for these entities, with significant discrepancies that were finally resolved through the development of a new classification (WHO-EORTC classification for cutaneous lymphomas), which standardizes criteria that had previously been different. We present two new cases of primary cutaneous diffuse large B-cell lymphoma of the leg according to the new classification.     

Survival data for 299 patients with primary cutaneous lymphomas: a monocentre study

The aim of this study was retrospectively to assess the validity of the 2005 WHO-EORTC classification for primary cutaneous lymphomas (PCL) in a large cohort of patients of a single German skin cancer unit. All patients with PCLs consecutively visiting our hospital between January 1980 and December 2005 were included in a retrospective monocentre study, analysing their histological and clinical data. A total of 312 patients fulfilled the inclusion criteria for PCL. In 299 patients clinical information and paraffin material were sufficient for detailed classification. Of the 299 patients, 63% expressed a T-cell and 37% a B-cell phenotype. Mycosis fungoides was the entity with the highest frequency (30.9%), followed by primary cutaneous follicle centre lymphomas (16.9%) and lymphomatoid papulosis (15.9%). The mean follow-up period was 38.4 months. Five-year disease-specific survival was 80.5% for mycosis fungoides, 92.5% in primary cutaneous anaplastic large cell lymphoma, 100% in lymphomatoid papulosis, 98.1% in primary cutaneous follicle center lymphoma, 100% in primary cutaneous marginal zone lymphoma and 63.2% in diffuse large B-cell lymphoma, leg type. Our data are in line with the data collected by the WHO-EORTC. This is further evidence for the reliability of the WHO-EORTC classification and staging system.     

Composite cutaneous lymphoma of diffuse large B‐cell lymphoma‐leg type and subcutaneous panniculitis‐like T‐cell lymphoma

Composite lymphoma (CL) is a rare disease defined by the occurrence of two distinct lymphomas within a single tissue at the same time. We present the case of an 89‐year‐old male with a clinical history of immunoglobulin M monoclonal gammopathy of undetermined significance. The patient presented cutaneous eruption of nodules on the right bottom and arm. An excisional biopsy revealed cutaneous infiltration composed of two components. The first one consisted of large B‐cells with CD20+/MUM1+/BCL2+ phenotype whereas the second one involved the subcutaneous fat in a panniculitic manner, and was CD3+/CD8+/granzyme B+/TCRβF1+. The final diagnosis was CL of primary cutaneous large B‐cell lymphoma‐leg type (PCLBCL‐leg type) and subcutaneous panniculitis‐like T‐cell lymphoma (SPTCL). We report and characterize for the first time coexistent PCLBCL‐leg type and SPTCL in a patient.     

The new World Health Organization-European Organization for Research and Treatment of Cancer classification for cutaneous lymphomas: a practical marriage of two giants

Following consensus meetings of the two parent organizations, a new World Health Organization-European Organization for Research and Treatment of Cancer (WHO-EORTC) classification for primary cutaneous lymphomas has recently been published. This important development will now end the ongoing debate as to which of these was the preferred classification. The new classification will facilitate more uniformity in diagnosis, management and treatment of cutaneous lymphomas. In particular, it provides a useful distinction between indolent and more aggressive types of primary cutaneous lymphoma and provides practical advice on preferred management and treatment regimens. This will thereby prevent patients receiving high-grade treatment for low-grade biological disease. This review focuses on those diseases which have found new consensus agreement compared with the original WHO and EORTC classifications. In cutaneous T-cell lymphomas, these include folliculotropic mycosis fungoides, defining features of Sézary syndrome, primary cutaneous CD30+ lymphoproliferative disorders (primary cutaneous anaplastic large cell lymphoma, lymphomatoid papulosis and borderline lesions) and subcutaneous panniculitis-like T-cell lymphoma. Primary cutaneous CD4+ small/medium-sized pleomorphic T-cell lymphoma, primary cutaneous aggressive epidermotropic CD8+ T-cell lymphoma and cutaneous gamma/delta T-cell lymphoma are allocated provisional entry status and thereby afford better definitions for some cases of currently unspecified primary cutaneous peripheral T-cell lymphoma. In cutaneous B-cell lymphomas, diseases which have found new consensus agreement include primary cutaneous marginal zone B-cell lymphoma, primary cutaneous follicular centre lymphoma, primary cutaneous diffuse large B-cell lymphoma, leg type and primary cutaneous diffuse large B-cell lymphoma, other. CD4+/CD56+ haematodermic neoplasm (early plasmacytoid dendritic cell leukaemia/lymphoma) now appears as a precursor haematological neoplasm and replaces the previous terminology of blastic NK-cell lymphoma. Other haematopoietic and lymphoid tumours involving the skin, as part of systemic disease, will appear in the forthcoming WHO publication Tumours of the Skin. The new classification raises interesting new problems and questions about primary cutaneous lymphoma and some of these are discussed in this article. It is, however, a splendid signpost indicating the direction in which research in cutaneous lymphoma needs to go. In the interim, we have an international consensus classification which is clinically meaningful.     

Primary cutaneous diffuse large B-cell lymphoma, leg type: clinicopathologic features and prognostic analysis in 60 cases

OBJECTIVES: To describe clinicopathologic features and to identify prognostic factors in a large series of primary cutaneous diffuse large B-cell lymphoma, leg type (PCLBCL LT), as defined in the recent World Health Organization-European Organization for Research and Treatment of Cancer classification of cutaneous lymphomas. DESIGN: Retrospective multicenter study from the French Study Group on Cutaneous Lymphomas. SETTING: Nineteen departments of dermatology in 10 regions of France. PATIENTS: Sixty patients with a PCLBCL LT included in the registry of the French Study Group on Cutaneous Lymphomas. MAIN OUTCOME MEASURES: Age, sex, outcome, therapy, B symptoms, cutaneous extent, number of lesions, location (leg vs nonleg), serum lactate dehydrogenase level, and MUM-1 and Bcl-2 expression were recorded. Disease-specific survival was used as the main end point. Prognostic factors were identified using a Cox proportional hazards model. RESULTS: Primary cutaneous diffuse large B-cell lymphoma, leg type is characterized by a predilection for the leg (72%), a high proportion of Bcl-2 expression (85%), an advanced age at onset (mean age, 76 years), and frequent relapses and extracutaneous dissemination. The overall 5-year disease-specific survival rate was 41%. Location on the leg and multiple skin lesions were predictive of death in multivariate analysis. Although no variable related to therapy was significantly associated with survival, patients recently treated with combinations of anthracycline-containing chemotherapies and rituximab had a more favorable short-term outcome. CONCLUSIONS: Primary cutaneous diffuse large B-cell lymphoma, leg type is a distinct entity with a poor prognosis, particularly in patients with multiple tumors on the legs. Despite the advanced age of many patients, the prognosis could be improved with combinations of anthracycline-containing chemotherapies and rituximab.     

New aspects in the biology of cutaneous B-cell lymphomas

Immunologic and molecular genetic studies greatly contributed to a better understanding and interpretation of the distinct clinico-pathologic features of primary cutaneous B-cell lymphomas (CBCL), which are the basis for the consensus WHO-EORTC classification. There is increasingly accumulating evidence that these well defined clinico-pathologic entities of CBCL have specific immunologic and molecular features, which further support their nosologic categorization as well as either interesting similarities with other extranodal B-cell lymphomas or definite peculiarities as compared to nodal B-cell lymphomas of similar histotype (specifically, follicle center lymphoma and diffuse large B-cell lymphoma).     

Primary cutaneous B-cell lymphomas

Cutaneous B-cell lymphomas (CBCL) are the second most common form of primary cutaneous lymphomas. The cutaneous follicle center lymphoma and the cutaneous marginal zone lymphoma (extranodal MALT type lymphoma) account for the vast majority of CBCL and manifest with nodules. These two lymphoma entities have an indolent, slowly progressive course and an excellent prognosis despite a high rate of recurrences. In contrast, cutaneous diffuse large B-cell lymphoma, leg type, and other rare forms of CBCL display an impaired prognosis and therefore require to be treated with multiagent chemotherapy and anti-CD20 monoclonal antibodies in most cases. Clinico-pathologic correlation, histology with immunohistochemical profile and genotyping as well as staging examinations are crucial diagnostic elements in the work-up of CBCL.     

Expression of the bcl-6 and MUM1/IRF4 proteins correlate with overall and disease-specific survival in patients with primary cutaneous large B-cell lymphoma: a tissue microarray study

BACKGROUND: Systemic B-cell lymphomas have been studied using microarrays, which has led to a better understanding of their molecular characteristics. Initial microarray studies of these lymphomas have implicated several genes as important predictors of outcome. In this study, we used a tissue microarray (TMA) to characterize primary cutaneous large B-cell lymphomas (PCLBCL). METHODS: We studied 14 patients for whom clinical follow up was available, including four patients whose lesions were limited to the leg on presentation. Immunohistochemical staining with CD20, CD44, CD21, CD5, CD10, bcl-2, bcl-6, Ki67, p53, and multiple myeloma 1 (MUM1) was examined. RESULTS: Our results identify two subgroups of lymphomas. The first group showed staining with bcl-6 and had an overall survival of 176 months (p = 0.003). The majority of this group was negative for MUM1. The second group lacked staining with bcl-6 and had an overall survival of 26 months, with a majority of these cases staining with MUM1. Three of four patients with PCLBCL of the leg showed no staining with bcl-6. CONCLUSIONS: Our study demonstrates the utility of TMAs in the analysis of PCLBCL and that expression of bcl-6 and MUM1 correlates with survival.     

Borrelia burgdorferi-associated lymphocytoma cutis simulating a primary cutaneous large B-cell lymphoma

The distinction between primary cutaneous B-cell lymphoma and B-cell pseudolymphoma on a histologic basis may be difficult, particularly in some cases of Borrelia burgdorferi-associated lymphoid proliferations. We report two cases of B. burgdorferi-associated pseudolymphoma that showed a dense infiltrate with a predominance of large atypical B cells. Because of this misleading histologic feature, a diagnosis of primary cutaneous large B-cell lymphoma was first suspected in both cases. In one case, successive recurrences led to aggressive therapies before the B. burgdorferi infection was recognized. However, a detailed review of histologic and immunohistochemical features was finally suggestive of a B. burgdorferi-associated pseudolymphoma in both cases. The etiologic role of B. burgdorferi was confirmed by serology, polymerase chain reaction analysis of B. burgdorferi DNA within the lesional skin, and response to antibiotic therapy. Because the distinction between B. burgdorferi-associated pseudolymphoma and primary cutaneous B-cell lymphomas may be difficult and true B. burgdorferi-associated B-cell lymphomas have been described, we suggest that antibiotic therapy should be considered as a first-line treatment in suspected or confirmed cases of primary cutaneous B-cell lymphoma in regions with endemic B. burgdorferi infection.     

Primary cutaneous B-cell lymphoma leg type: good response with the RADHAP 21 protocol

Primary cutaneous lymphomas are defined as the ones that exclusively affect the skin for up to 6 months after the diagnosis. B-cell lymphomas represent 20-25% of primary cutaneous lymphomas and have, among its subtypes, the leg type, which represents 10 to 20% of cutaneous B-cell lymphomas, generally affecting elderly people and with an intermediate prognosis. This is the report of a rare case of a leg-type B-cell lymphoma with an exuberant clinical presentation affecting a young male patient.     

Characteristics of cutaneous lymphomas in Osaka, Japan (1988-1999) based on the European Organization for Research and Treatment of Cancer classification

Based on accumulating information, European investigators proposed a new classification for primary cutaneous lymphomas known as the European Organization for Research and Treatment of Cancer (EORTC) classification. The clinical utility of this classification in Japanese cases has not been evaluated. Material from 65 patients with cutaneous lymphomas (48 with primary disease and 17 with secondary disease) who were admitted to Osaka University Hospital during the period 1988 through 1999 was reviewed. Immunohistochemical analysis was performed in all cases. Cutaneous T-cell lymphoma (CTCL) comprised mycosis fungoides (15 cases), Sézary syndrome (1 case), lymphomatoid papulosis (5 cases), large cell CTCL (13 cases), pleomorphic small- or medium-sized CTCL (2 cases), and cutaneous natural killer /T-cell lymphoma (4 cases). B-cell lymphomas comprised 7 cases of follicle center cell lymphoma and 1 case of diffuse large B-cell lymphoma of the leg. Each category of disease in the EORTC scheme showed its characteristic features in our series. Five of 13 large cell CTCL cases were positive for CD30, and 5 were negative. The 5-year survival rate of patients with large cell CTCL CD30+ disease was 100% and that of patients with CD30- disease was 0%. (p > 0.1). Only 1 of 7 CTCL cases expressing CD30 was ALK-1+, and all 7 cases showed a favorable clinical course. The EORTC classification is effective in dealing with Japanese cases of cutaneous lymphomas.     

Simultaneous aberrations of single CDKN2A network components and a high Rb phosphorylation status can differentiate subgroups of primary cutaneous B-cell lymphomas

The cyclin-dependent kinase inhibitor 2A (CDKN2A) gene on chromosome 9p21 encodes p16 (INK4A), the inhibitor of the CDK4/retinoblastoma (Rb) cell proliferation pathway, as well as p14 (ARF), which controls p53-dependent pathways. Inactivation of p16 has previously been associated with the prognostically unfavourable primary cutaneous diffuse large B-cell lymphoma, leg type (PCLBCL, LT). In this work, we analysed 22 tumors [nine primary cutaneous follicle centre lymphomas (PCFCL), seven primary cutaneous marginal zone lymphomas (PCMZL) and six PCLBCL, LT] not only for alterations of the p16 gene but also for p14, p53 and Rb by fluorescence in situ hybridization (FISH) and immunohistochemistry. In most PCLBCL, LT (4/6) alterations of CDKN2A (two biallelic deletions, one monoallelic deletion and one trisomy 9) and in addition the highest frequency of deletions of p53 (3/6) and Rb (3/6) were detected. p16 was not expressed but very high levels of phosphorylated Rb, indicating a functional effect of genomic CDKN2A alterations on the protein level in PCLBCL, LT. Regarding the p14/p53 axis, PCLBCL, LT showed a variable expression. Neither PCFCL nor PCMZL showed alterations of CDKN2A and also deletions of p53 or Rb were extremely rare in these subtypes. Exclusively in PCMZL, p53 protein was consistently lacking. In conclusion, only PCLBCL, LT is characterized by a high frequency of aberrations of the CDKN2A network components in both important tumor suppressor pathways regulated by the CDKN2A gene. Moreover, PCLBCL, LT appears to be distinguishable from PCMZL not only by its level of p53 expression but also by its stage of Rb phosphorylation. The latter may also apply to a subgroup of PCFCL.     

Die Therapie der primären kutanen B-Zell-Lymphome

BACKGROUND AND OBJECTIVE: Primary cutaneous B-cell lymphomas (PCBCL) represent a unique type of extranodal B-cell lymphomas. Recently, the "European Organization for Research and Treatment of Cancer (EORTC)-Cutaneous Lymphoma Study Group" classified PCBCL into two major groups: one with low-grade malignancy and excellent prognosis (follicle center cell lymphoma, immunocytoma/marginal zone B-cell lymphoma) and the other with intermediate malignancy and worse prognosis (large B-cell lymphoma of the leg). The clinical course and the prognosis of both groups clearly distinguish them from nodal lymphomas with similar morphological aspects, thus underlying the need for different treatment modalities. PATIENTS/METHODS: We investigated retrospectively the therapeutic data from 51 patients with PCBCL (40 low grade lymphomas, 11 large B-cell lymphomas). Several treatment modalities were used: total excision, radiotherapy, polychemotherapy, systemic corticosteroids, systemic antibiotics, as well as a variety of combination treatments. RESULTS: Recurrence, dissemination and/or death of the patients were not significantly related to any single treatment modality. CONCLUSIONS: In our opinion, the choice of treatment for PCBCL depends on the histologic classification, the number, spread and localization of the infiltrates, and on the general condition of the patient.     

Bone involvement in two cases of thoracic primary cutaneous diffuse large B-cell lymphoma, leg type

Primary cutaneous diffuse large B-cell lymphoma, leg type (PCLBCL-LT), is defined by a predominance of confluent sheets of centroblasts and immunoblasts, which strongly express Bcl-2 protein. This cutaneous lymphoma is mainly characterized by the development of skin lesions on the lower leg. Other localizations are possible (namely non-leg PCLBCL-LT) and usually affect younger patients. PCLBCL-LT is distinguished from the two other subtypes of primary cutaneous B-cell lymphomas by its immunohistopathological features, its aggressive clinical behaviour with a worse prognosis linked to skin recurrences, but also secondary extracutaneous spread. Bone involvement underlying skin lesions has been reported in few series and cases reports during PCLBCL-LT. We describe here two aggressive cases of PCLBCL-LT with high burden and infiltrative thoracic tumours, with localized bone involvement.     

The skin-associated lymphoid tissue-related B-cell lymphomas

Primary cutaneous B-cell lymphomas (CBCLs) should be clearly separated from non-Hodgkin's B-cell lymphomas with secondary cutaneous involvement and from cutaneous B-cell pseudolymphomas. The majority of CBCLs are characterized by a homogeneous clinical presentation and behavior, with good response to local radiotherapy, low tendency to extracutaneous spread, and excellent prognosis. According to the European Organization for Research on the Treatment of Cancer classification of primary cutaneous lymphomas, CBCLs with an indolent behavior are divided into 2 subgroups: follicular center cell lymphoma and immunocytoma/marginal zone lymphoma, due to putative histologic similarities with their purported nodal counterparts. In addition, a third subgroup with intermediate prognosis (large B-cell lymphoma of the leg) is identified. Conversely, the identification of distinct subgroups is disputable from a strictly histologic, immunophenotypic, and genotypic point of view, and has neither correlation with the clinical course nor the prognosis of the disease. Moreover, the majority of CBCLs show a uniform immunophenotype (CD5-, CD10-) and genotype (lack of bcl-1/bcl-2 and c-myc gene rearrangement) of neoplastic cells. Therefore, we favor the use of the term Skin-Associated Lymphoid Tissue (SALT)-related B-cell lymphomas, due to the close similarities between CBCLs and mucosa-associated lymphoid tissue (MALT) lymphomas, and the evidence for an acquired B-cell arm of SALT.     

Cutaneous Lymphomas: from Morphology to Chip Technology

Cutaneous lymphomas represent a heterogenous group of malignant lymphoid diseases with particular tropism for the skin. Prognosis and treatment depend on the type of lymphoma, thus precise diagnosis and classification are of paramount importance. Classification of cutaneous lymphomas relies on a synthesis of all available information, including clinical history and presentation, histopathology, immunophenotype, and molecular data. Thanks to the efforts of the lymphoma groups of both the World Health Organization (WHO) and the European Organization for Research and Treatment of Cancer (EORTC), a joint WHO-EORTC classification for primary cutaneous lymphomas has been proposed in 2005. The WHO-EORTC classification has been adsorbed with minor changes in the 2008 WHO classification of tumours of haematopoietic and lymphoid tissues, thus including for the first time primary cutaneous lymphomas as distinct subtypes of extranodal lymphomas in a general classification of lymphomas.