Fibrin-Associated EBV-Positive Large B-Cell Lymphoma Incidentally Found Within a Multinodular Goiter.

Fibrin-associated diffuse large B-cell lymphoma (fibrin-associated DLBCL) is a very rare subtype of Epstein-Barr virus (EBV)-associated DLBCL that usually develops within fibrin-rich lesions such as cardiac myxoma, chronic hematoma, thrombus, pseudocysts or cysts, prosthetic devices or breast implants. The pathogenesis as well as the clinicopathologic features of this usually indolent lymphoproliferative disorder, which are based on the analysis of a relatively limited number of cases, are still poorly known. Herein, we report a case of fibrin-associated DLBCL that was incidentally found within a multinodular goiter, a location not yet reported to our knowledge. Our findings not only illustrate further the specific nature of this peculiar lymphoproliferative disorder but also allow some interesting comments on its pathogenesis.

Sessile Serrated Lesion of the Appendix in a Teenage Girl.

According to the literature, serrated lesions and polyps of the appendix are extremely rare in children or teenagers. Herein, we present the pathologic and molecular features of a sessile serrated lesion (SSL) that was incidentally found in the appendix of a teenage girl. Our findings not only illustrate that appendiceal SSL may occur in young patients such as teenagers but also confirm further that BRAF V600E mutation may be found in a subset of these neoplastic lesions.

Lymph node involvement by enteropathy-like indolent NK-cell proliferation.

Natural killer (NK)-cell enteropathy (NKCE) and lymphomatoid gastropathy (LG) are closely related lymphoproliferative disorders (LPDs) composed of mature and Epstein-Barr virus (EBV)-negative NK-cells. Although these uncommon and indolent lymphoid proliferations mostly arise within the gastrointestinal (GI) tract as their designations implies, a few cases have been reported outside the GI tract. We hereby describe a unique case of lymph node infiltration by such EBV-negative NK-cell proliferation fortuitously found during routine examination of a gallbladder resected for biliary lithiasis. The histologic, phenotypic, and molecular features of this NK-cell proliferation, which were very similar if not identical to those previously reported in NKCE or LG, suggest that similar indolent EBV-negative NK-cell LPDs may also occasionally involve lymph nodes.

Genomic profiling of myeloma: the best approach, a comparison of cytogenetics, FISH and array-CGH of 112 myeloma cases.

BACKGROUND: Chromosome abnormalities are important prognostic factors in myeloma allowing risk stratification of patients. Different techniques are available for their detection including cytogenetics, Fluorescent In Situ Hybridisation (FISH) and array Competitive Genomic Hybridisation (CGH). This study aimed to assess the validity and usefulness of each technique in a diagnostic setting. METHODS: 112 myeloma cases were analysed by whole bone marrow cytogenetics and by FISH and array CGH performed on purified plasma cell populations. RESULTS: Clonal abnormalities were identified in 30% of cases by cytogenetics and 97% by FISH and array CGH. By combining array and FISH results abnormalities were detected in 99% of cases and, if cytogenetic analysis was also considered, abnormalities were detected in 100% of cases. CONCLUSIONS: Cytogenetic analysis is of limited value in myeloma. Array CGH and FISH are highly specific tests allowing the identification of aberrations in virtually all cases. The two techniques are complementary and need to be combined in order to provide a comprehensive analysis of all clinically relevant aberrations in myeloma.

Tumor-forming plasmacytoid dendritic cells associated with myeloid neoplasms. Report of a peculiar case with histopathologic features masquerading as lupus erythematosus.

Plasmacytoid dendritic cells (PDC) belong to a subtype of dendritic cells that are normally absent in healthy skin. In some inflammatory diseases of the skin, especially lupus erythematosus (LE), these cells are occasionally recruited in great amounts, which can be used as a helpful clue for diagnosis. Rarely, PDC may also accumulate in the skin of patients with myeloid leukemia, a yet poorly known condition currently called 'tumor-forming PDC associated with myeloid neoplasms'. In this study, we describe a patient with unsuspected chronic myelomonocytic leukemia who developed cutaneous lesions characterized by a dermal infiltrate rich in PDC. Similarly to LE, such neoplastic PDC were accompanied by interface dermatitis-like changes, but displayed an aberrant phenotype and shared the same chromosomal abnormality with the leukemic cells identified in the bone marrow, thus revealing the neoplastic nature of the process. This observation illustrates that tumor-forming PDC associated with myeloid neoplasms may microscopically mimic LE in some patients. Accordingly, a hematologic workup is recommended in any skin lesion featuring excessive numbers of PDC, even if morphological alterations suggestive of interface dermatitis are found.

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.

Chronic lymphocytic leukemia mimicking recurrent carcinoma of the breast: case report and review of the literature.

Secondary localization of chronic lymphocytic leukemia (CLL) in breast is rare, while concurrent invasive ductal carcinoma and CLL manifesting as a collision tumor in breast is extremely rare. The observation of a CLL infiltration closely associated with a distinct breast neoplasm with the absence of any other localization for the leukemia is an indisputable argument for a relationship between the two diseases. The presence of both tumors is not simply due to chance. This association (CLL and carcinoma) has also been described in other organs. Hereafter, we report a second case of an 80 year-old woman in whom a leukemic infiltrate was confined to the region immediately surrounding poorly differentiated primary breast carcinoma, and we will discuss the association between CLL and carcinoma.

An unusual presentation of a cystic duplication of the sigmoid colon entirely lined with squamous epithelium.

Alimentary tract duplications are rare congenital malformations that occur most commonly in the jejunoileal part of the gastrointestinal tract. Management of this pathologic condition is usually drawn up. We report a case of descending colonic communicating duplication in which clinical presentation and anatomopathologic results were unexpected. A slightly echogenic abdominal mass reaching 72 x 36 mm in the left flank was diagnosed in a female fetus during the third trimester ultrasound examination. At birth, volume of the mass rapidly evolved, and despite no intestinal obstruction was observed by compression of the adjacent gastrointestinal tract, abdomen was distended. Abdominal plain film showed a large air collection, and the barium enema demonstrated a slight leak of contrast in the aerated mass, suggesting a communication with the sigmoid colon. No other abnormalities were seen. The patient underwent surgery in emergency. The mass was then totally excised through an antimesenteric resection of the tubular tract joining cystic mass and sigmoid colon. A lateral suture of the colon was subsequently performed. The wall of the duplication is usually composed of a smooth muscle layer covered by an epithelium, mostly of intestinal type. Herein, we describe a descending colonic duplication completely lined with nonkeratinizing squamous epithelium. Therefore, the association of a colonic mucosa (of endodermic origin) and a squamous epithelium (derived from the ectoderm) in our case is an interesting finding and is not explained by the various theories. Furthermore, the clinical characteristics, diagnosis, and treatment of intestinal duplications are discussed with regard to literature.

Lymphoscintigraphy in angiomyomatous hamartomas and primary lower limb lymphedema.

PURPOSE: Angiomyomatous hamartoma (AH) of the lymph node is a rare vascular benign disease of unknown etiology with a predisposition for the lymph nodes of the inguinal area. Only 18 cases have been described up to now in the literature and the disorder was reported to be associated with lymphedema or swelling of the ipsilateral limb in 4 patients. However, scintigraphic investigation of the lymphatic system in these patients was reported in only 2 cases. MATERIAL AND METHODS: Five patients where the biopsy of inguinal nodes for suspected lymphadenitis led to the diagnosis of angiomyomatous hamartoma were investigated using lymphoscintigraphic techniques (1 girl aged 15; 1 boy aged 9 at the time of first biopsy and 11 at the time of the second one; and 3 men aged 30, 50, and 57). The operated limb was lymphedematous in 3 and 1 developed lymphedema after biopsy. The fifth patient developed a contralateral lymphedema after his second nodal biopsy. RESULTS: In all cases, lymphoscintigraphic investigation of the limbs showed extensive lymph node abnormalities on the operated side and in 4 cases on the opposite side. CONCLUSIONS: These observations support not only the hypothesis that lymphatic disturbance was involved in the pathogenesis of these tumors but also the proposition that lymphoscintigraphy should be performed in cases of inguinal lymphadenitis of unknown origin to diagnose the underlying situation of latent lymphedema.

Atypical hyperplasia of the marginal zone of B follicles in a polymorphic Epstein-Barr virus-associated lymphoproliferative disorder occurring in an adolescent with human immunodeficiency virus infection.

Epstein-Barr virus (EBV)-associated lymphoid proliferations that are similar to post-transplantation lymphoproliferative disorders may occasionally occur in the setting of human immunodeficiency virus (HIV) infection. Herein, we describe such a lesion involving the adenoids in a HIV-seropositive adolescent who acquired immunity against EBV during childhood. On microscopic examination, the marginal zone of B follicles and the interfollicular area were enlarged due to the accumulation of small or intermediate-sized lymphocytes, immunoblasts, epithelioid histiocytes, and plasma cells. A few atypical immunoblasts resembling Reed-Sternberg cells were also present. Most of the cells seen in these expanded regions belonged to the B-cell lineage and displayed a phenotype consistent with that of postgerminal center B cells. No clonal rearrangement of the genes coding for the heavy chain of the immunoglobulin could be demonstrated by polymerase chain reaction analysis. In-situ hybridization studies revealed the presence of EBV early RNA in a significant number of these cells, which suggests the participation of this virus in the pathogenesis of such a B-cell proliferation. The clinical course was benign; no progression or recurrence could be seen more than 24 months after the diagnosis. This atypical lymphoproliferative disorder is probably related to polyclonal reactivation of a latent EBV infection due to a local or systemic immune imbalance induced by HIV replication. Recognition of this reactive condition is important to prevent overtreatment.

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 Castleman's 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 IgMlambda 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.