Jean-Louis Dargent

Primary low-grade B-cell lymphoma of MALT-type occurring in the liver: a study of two cases

BACKGROUND/METHODS Primary non-Hodgkins lymphomas of the liver are rare. One specific clinico-pathological entity has been identified as hepatosplenic gamma/delta T-cell lymphoma. Recently, another distinct primary lymphoma of the liver has been recognised as primary low-grade hepatic B-cell lymphoma of mucosa-associated lymphoid tissue (MALT), based on a study comprising four cases. We analysed two additional cases of this particular non-Hodgkins lymphoma, not only by morphology and phenotyping, but also by genotyping and cytogenetic analysis. RESULTS This type of non-Hodgkins lymphoma is characterised by a dense lymphoid infiltrate, localised in the portal tracts, and is associated with lympho-epithelial lesions of the bile ducts, thereby mimicking hepatitis or an inflammatory bile duct disorder. In one of our cases, translocation t(3;14)(q27;q32) was identified as the sole cytogenetic abnormality. A high incidence of trisomy 3 has been associated with marginal zone B-cell lymphomas, and fluorescence in situ hybridisation as well as comparative genomic hybridisation studies have shown frequent involvement of the long arm of chromosome 3. Nevertheless, t(3;14)(q27;q32) involving BCL6 gene, located at 3q27, has not yet been found. CONCLUSION Our findings suggest a role for the BCL6 gene in the histogenesis of this particular lymphoma.

Leukaemia and lymphoma of the appendix presenting as acute appendicitis or acute abdomen: Four case reports with a review of the literature

Abstract Leukaemic and lymphomatous infiltration of the appendix is rare and even rarer is acute appendicitis as the initial manifestation. From our routine biopsy material we collected four cases of haematological malignancies presenting as acute appendicitis or acute abdomen, caused or accompanied by tumoral infiltration of the appendix. Appendicitis was the initial manifestation that allowed diagnosis of the underlying disease. The clinical histories and histological examinations of the appendices and of one autopsy are described. We report the first detailed description of acute myeloid leukaemia involving the appendix, and three cases of lymphomatous infiltration of the appendix presenting with appendicitis, and give an overview of the literature. In these days of budgetary cuts in national health services, where one may be tempted not to have seemingly commonplace cases of appendicitis histologically verified, our cases emphasize that careful histopathological examination of all appendectomy specimens should be mandatory. Despite the fact that leukaemia and lymphoma of the appendix are rare, our cases illustrate that these must be included in the differential diagnosis of acute appendicitis and that physicians and surgeons have to be aware of these conditions.

Subcutaneous panniculitis-like T-cell lymphoma: further evidence for a distinct neoplasm originating from large granular lymphocytes of T/NK phenotype

We report the case of a 20 year‐old caucasian woman who presented a primary subcutaneous panniculitis‐like T‐cell lymphoma (SPTCL) as an invasive tumor of the chest wall. Herein, the neoplastic cells were found to express a CD3+CD8+ phenotype but also displayed variably the natural killer (NK)‐associated antigens CD56 and CD57 as well as granzyme B. On cytological examination, these cells showed a large granular lymphocyte (LGL)‐like morphology with presence of azurophilic granules in their cytoplasm. Electron dense and membrane bound granules like those found in cytotoxic T lymphocytes (CTL) were also demonstrated by electron microscopy. Neither rearrangement of the T‐cell receptor subunits nor Epstein‐Barr virus (EBV) genome was observed at the molecular level. The LGL‐like features of the neoplastic cells found in this case and the presence of NK‐associated antigens provide additional support to the cytotoxic derivation of most SPTCL.

Cellular angiofibroma of the vulva: a clinicopathological study of two cases with documentation of some unusual features and review of the literature.

Background:  Cellular angiofibroma (CA) of the vulva is a recently described condition, whose clinical and pathological features are poorly known.

Development of a calcifying fibrous pseudotumour within a lesion of Castleman disease, hyaline-vascular subtype

A nine year old boy with localised Castleman disease of the hyaline-vascular subtype developed a calcifying fibrous pseudotumour. This pathological association does not appear to have been described before. In this case, the development of this very unusual soft tissue tumour-like process was thought to be related to a previous fine needle aspiration biopsy, which was performed because of lymphadenopathy localised to the right inguinal area. This case provides further evidence of the reactive nature of calcifying fibrous pseudotumour and also broadens the pathological spectrum of the stromal cell proliferation that occasionally supervenes within lesions of Castleman disease, hyaline-vascular type.

Liver involvement by lymphoma: Identification of a distinctive pattern of infiltration related to T-cell/histiocyte-rich B-cell lymphoma

Liver biopsy specimens from 62 patients with hepatic infiltration by miscellaneous lymphomas were retrospectively studied. The most relevant histologic features of liver infiltration in the various subtypes of lymphomas were then compared. In this study, diffuse large B-cell lymphomas were the most common neoplasm to involve the liver as primary or secondary tumors (64.5% of cases). The next most common lymphoma to involve the liver was Hodgkins disease, found in 19.4% of cases, followed by peripheral T-cell lymphomas (9.7%), follicle center cell lymphomas (4.8%), and primary hepatic marginal zone B-cell lymphoma of the mucosa-associated lymphoid tissue type (1.6%). Within the group of large B-cell lymphomas, a particular subset of cases was found, which was identified as T-cell/histiocyte-rich B-cell lymphoma. This rare variant of diffuse large B-cell lymphomas involves the liver in a very distinctive way that may mimic, on both clinical and histologic grounds, inflammatory liver disease or hepatic infiltration by Hodgkins disease. Although these diagnostic ambiguities can be easily solved by current immunohistochemistry, awareness of these potentially misleading features is mandatory to avoid misdiagnosis.

Plasmablastic microlymphoma occurring in human herpesvirus 8 (HHV-8)-positive multicentric Castleman's disease and featuring a follicular growth pattern†

Plasmablastic microlymphoma (PML) is defined as the accumulation of monotypic but polyclonal plasmablasts in lymphoid tissues involved in human herpes virus 8 (HHV‐8)‐positive multicentric Castlemans disease (MCD). So far, the nature of this very rare condition remains poorly determined. In this study, we describe a human immunodeficiency virus (HIV)‐seropositive patient who developed a PML in the setting of HHV‐8‐positive MCD. In contrast to the cases previously reported, most of the plasmablasts in our patient were localized within the germinal center (GC) of lymphoid follicles. These plasmablasts expressed the multiple myeloma‐1/interferon regulatory factor‐4 (MUM1/IRF4) protein as well as IgMλ in a monotypic fashion. They did not show any immunoreactivity with antibodies directed against Pax‐5, CD20, CD79a, CD10, CD30, CD23, CD138, epithelial membrane antigen (EMA) or BCL‐6. These cells exhibited a high proliferation rate, expressed the HHV‐8 latent nuclear antigen‐1, and secreted the HHV‐8 viral homologue of human interleukin‐6. Polymerase chain reaction analysis did not demonstrate any clonal rearrangement of the genes coding for the heavy chain of the immunoglobulin. Moreover, no Epstein‐Barr virus (EBV) RNA transcript could be found, using in situ hybridization. The present case illustrates that PML may arise within the GC of lymphoid follicles in the absence of EBV coinfection. In our opinion, PML occurring in MCD likely represents a variant of HHV‐8‐positive MCD in which lytic HHV‐8 replication is particularly prominent, due to a local or systemic immune imbalance.

Unusual T Cell Pseudolymphoma with Features of So-Called Pseudolymphomatous Folliculitis

Unusual T Cell Pseudolymphoma with Features of So-Called Pseudolymphomatous Folliculitis J.L. Dargent a, J. Deboisb, U. Sass c, A. Theunis c, J. André c, T. Simonartd aDepartment of Pathology, CHU Saint-Pierre/ULB-Institut Jules-Bordet, Brussels, b Huidziekten, Mechelen, cDermatopathology Unit, Department of Dermatology, CHU Saint-Pierre, and dDepartment of Dermatology, Hôpital Erasme, Brussels, Belgium

Disseminated angiosarcoma presenting as a hemophagocytic syndrome in a renal allograft recipient

Abstract A case of angiosarcoma arising in the setting of transplantation is reported. This rare and malignant tumor of the endothelial system is seldom observed in allograft recipients, with only seven cases having been previously reported. What is interesting about the present observation is that the tumor is thought to have developed in the vicinity of a Dacron graft and that it showed prominent erythrophago‐cyte‐like activity. This activity was associated with a particular clinical syndrome that shared some attributes with infection‐associated hemophagocytic syndrome.

Cutaneous accumulation of plasmacytoid dendritic cells associated with acute myeloid leukemia: a rare condition distinct from blastic plasmacytoid dendritic cell neoplasm.

A cutaneous infiltrate composed of plasmacytoid dendritic cells may occasionally occur in a patient suffering from a myeloid neoplasm. To date, the clinical and pathological features associated with this event remains poorly characterized. Herein, we report a patient with acute myeloid leukemia who developed pruritic papules or erythematous plaques scattered on the skin. Microscopic examination showed a dermal infiltrate rich in plasmacytoid dendritic cells expressing CD4, CD43, CD68, granzyme B, CD123, CD303 [blood dendritic cell antigen 2 (BDCA‐2)], CD2‐associated protein (CD2AP) and T‐cell leukemia/lymphoma oncogene 1 (TCL1). Our observation illustrates further that cutaneous lesions associated with some myeloid neoplasms, especially those featuring a monocytic component, may be composed of plasmacytoid dendritic cells. Because of differences in clinical, pathological and genetic features, this rare condition should be distinguished from blastic plasmacytoid dendritic cell neoplasm.