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IgA was obtained from HlV-infected haemophilic patients and the intracellular signals triggered by its reaction with isolated rat intestinal strips were studied. HIV+IgA stained intestinal microvilli with a granular immunofluorescence pattern and bound to the muscarinic acetylcholine receptor (mAChR), displacing the specific muscarinic cholinergic antagonist QNB in a non-competitive manner. It triggered the signals that are the consequence of mAChR stimulation in the intestine. Thus, it decreased cAMP synthesis and increased guanosine 3':5'-cyclic monophosphate (cGMP) formation and phosphoinositide (PI) turnover of the intestine. In addition, it stimulated prostaglandin E2(PGE2) synthesis by intestinal strips. Through its effect on PGE2 synthesis. HIV+ IgA could have a dual action. On the one hand, it could enhance immunosuppression at a local level, favouring pathogen growth and subsequent intestinal dysfunction. On the other hand, PGE2 could directly increase intestinal motility and electrolyte/fluid loss. Both effects could be involved in intestinal damage in AIDS. [ABSTRACT FROM AUTHOR]

Nodal T- and NK-cell lymphomas are among the most frequent T-cell malignancies and most subtypes have aggressive clinical behavior. Evolving understanding of the biology and molecular characteristics of these lymphomas, as well as the development of new precision therapy approaches, underscores the importance of ongoing updates to the classification and diagnostic evaluation of this group of malignancies. Here, we discuss the classification of nodal T- and NK-cell lymphomas based on the 2022 International Consensus Classification of Mature Lymphoid Neoplasms (2022 ICC). Lymphomas of T-follicular helper cell origin are now grouped into a single entity, follicular helper T-cell lymphoma (TFH lymphoma), with three subtypes (angioimmunoblastic-type, follicular-type, and not otherwise specified), reflecting their common cellular origin and shared molecular and clinical characteristics. Classification of anaplastic large cell lymphoma (ALCL) remains essentially unchanged; DUSP22-rearranged cases are now considered a genetic subtype of ALK-negative ALCL. Primary nodal EBV-positive T-/NK-cell lymphoma is introduced as a new provisional entity; these cases were previously considered a variant of peripheral T-cell lymphoma, not otherwise specified (PTCL, NOS). PTCL, NOS remains a diagnosis of exclusion, with evolving molecular data indicating the presence of distinct subgroups, including PTCL-TBX21, PTCL-GATA3, and EBV-negative cytotoxic PTCLs. We also discuss diagnostic strategies to facilitate the 2022 ICC classification among nodal T- and NK-cell lymphomas and the distinction from nodal involvement by extranodal neoplasms., (© 2022. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Since the publication of the Revised European-American Classification of Lymphoid Neoplasms in 1994, subsequent updates of the classification of lymphoid neoplasms have been generated through iterative international efforts to achieve broad consensus among hematopathologists, geneticists, molecular scientists, and clinicians. Significant progress has recently been made in the characterization of malignancies of the immune system, with many new insights provided by genomic studies. They have led to this proposal. We have followed the same process that was successfully used for the third and fourth editions of the World Health Organization Classification of Hematologic Neoplasms. The definition, recommended studies, and criteria for the diagnosis of many entities have been extensively refined. Some categories considered provisional have now been upgraded to definite entities. Terminology for some diseases has been revised to adapt nomenclature to the current knowledge of their biology, but these modifications have been restricted to well-justified situations. Major findings from recent genomic studies have impacted the conceptual framework and diagnostic criteria for many disease entities. These changes will have an impact on optimal clinical management. The conclusions of this work are summarized in this report as the proposed International Consensus Classification of mature lymphoid, histiocytic, and dendritic cell tumors.

Conventionally, mantle cell lymphoma (MCL) is an aggressive CD5-positive B-cell malignancy with poor prognosis and limited survival. However, a small subset of patients presents with indolent disease and can be managed on a 'watch and wait' approach. CD5-negative MCL has recently been recognized as a more favorable variant of MCL, but its clinical and biological implications remain ill-defined. We performed the most extensive review to-date of all reported cases of CD5-negative MCL and included unpublished cases diagnosed at our institutions to further characterize this disease subset. Based on our analysis of 356 cases of CD5-negative MCL, we conclude that median overall survival exceeds 14 years and is independent of favorable prognostic markers such as leukemic non-nodal disease, absence of SOX11, and low Ki-67.

Extranodal NK/T-cell lymphoma (ENKTL) is an Epstein-Barr virus (EBV) associated lymphoma, prevalent in Asia and Latin America. Studies in Asian cohorts have identified some recurrent gene mutations in ENKTL; however, the mutational landscape of ENKTL in Latin America is unknown. In this study, we investigated the mutational profile and EBV strains of 71 ENKTL cases from Latin America (42 from Mexico, 17 from Peru, and 12 from Argentina) and compared it with Asian cohorts. The mutational analysis was performed by next generation sequencing (NGS) using an Ion AmpliSeq™ custom panel covering for the most frequently mutated genes identified in ENKTL. STAT3 was the most frequent mutated gene (16 cases: 23%), followed by MSN (10 cases; 14%), BCOR (9 cases; 13%), DDX3X (6 cases; 8%), TP53 (6 cases; 8%), MGA (3 cases; 4%), JAK3 (2 cases; 3%), and STAT5B (1 case; 1%). Mutations in STAT3, BCOR, and DDX3X were nearly mutually exclusive, suggesting different molecular pathways involved in the pathogenesis of ENKTL; whereas mutations in MGA, MSN, and TP53 were concomitant with other mutations. Most cases (75%) carried Type A EBV without the 30-bp LMP1 gene deletion. The overall survival was significantly associated with serum LDH level, Eastern Cooperative Oncology Group (ECOG) performance status, International Prognostic Index (IPI) score, and therapy (p < 0.05), but not associated with any mutation, EBV strain or deletion in EBV LMP1 gene. In conclusion, mutational analysis of ENKTL from Latin America reveals frequent gene mutations leading to activation of the JAK-STAT pathway (25%), mostly STAT3. Compared to Asian cohorts, BCOR, DDX3X  and TP53 mutations were also identified but with different frequencies. None of these mutations were associated with prognosis.

Background: The aim of this study was to determine the relative frequency of primary cutaneous lymphoma (PCL) in Argentina according to the new World Health Organization (WHO)-European Organization for the Research and Treatment of Cancer (EORTC) classification system., Methods: A total of 416 patients from 21 dermatology services were included during a 5-year period (2010-2015); these patients were classified using WHO-EORTC criteria., Results: There were 231 (55.2%) males and 185 (44.8%) females; the male-to-female ratio was 1.35. The median age of the patients was 57 years (range, 0-90 years). Most patients were Caucasian (79%), and only 16% of patients were registered as Amerindian. Most patients (387/416, 93%) had cutaneous T-cell lymphoma (CTCL); 28 patients (6.7%) were diagnosed with cutaneous B-cell lymphoma (CBCL). The most frequent CTCL subtypes, in decreasing order of prevalence, were mycosis fungoides (MF), including its variants (75.7%); CD30+ primary cutaneous lymphoproliferative disorders (7.2%); and Sézary syndrome (SS) (3.1%). Cutaneous follicle center lymphoma was the most common CBCL subtype (2.9%). In the subset of patients ≤20 years of age, the most common condition was MF (57%), followed by extranodal NK-T nasal-type lymphoma (14%)., Conclusions: This study revealed relatively higher rates of MF and lower rates of CBCL in Argentinean patients that have been reported in American and European countries., (© 2018 The International Society of Dermatology.)

Breast implant-associated anaplastic large cell lymphoma (BI-ALCL) is a rare T-cell lymphoma that arises around breast implants. Most patients manifest with periprosthetic effusion, whereas a subset of patients develops a tumor mass or lymph node involvement (LNI). The aim of this study is to describe the pathologic features of lymph nodes from patients with BI-ALCL and assess the prognostic impact of LNI. Clinical findings and histopathologic features of lymph nodes were assessed in 70 patients with BI-ALCL. LNI was defined by the histologic demonstration of ALCL in lymph nodes. Fourteen (20%) patients with BI-ALCL had LNI, all lymph nodes involved were regional, the most frequent were axillary (93%). The pattern of involvement was sinusoidal in 13 (92.9%) cases, often associated with perifollicular, interfollicular, and diffuse patterns. Two cases had Hodgkin-like patterns. The 5-year overall survival was 75% for patients with LNI and 97.9% for patients without LNI at presentation (P=0.003). Six of 49 (12.2%) of patients with tumor confined by the capsule had LNI, compared with LNI in 8/21 (38%) patients with tumor beyond the capsule. Most patients with LNI achieved complete remission after various therapeutic approaches. Two of 14 (14.3%) patients with LNI died of disease compared with 0/56 (0%) patients without LNI. Twenty percent of patients with BI-ALCL had LNI by lymphoma, most often in a sinusoidal pattern. We conclude that BI-ALCL beyond capsule is associated with a higher risk of LNI. Involvement of lymph nodes was associated with decreased overall survival. Misdiagnosis as Hodgkin lymphoma is a pitfall.

Epstein-Barr virus (EBV)-mediated B cell transformation is achieved predominantly through the action of latent proteins, but recent evidence suggests that lytic EBV replication has also a certain pathogenic role in lymphomagenesis, at least in the early phases of cell transformation. Particularly, in diffuse large B cell lymphoma (DLBCL), the EBV lytic cycle is by and large unexplored, so to disclose lytic cell contribution to lymphomagenesis, our aim was to evaluate viral early and late lytic gene expression in relation to several immune response markers in a series of EBV+ DLBCL from Argentina. An unexpected number of cells expressed lytic transcripts, being transcribed at the BZLF1, BHRF1, and BLLF1 locus, by real-time quantitative polymerase chain reaction. This lytic antigen expression was confirmed by immunohistochemical staining for BMRF1 early lytic protein, and a positive correlation between lytic and latent genes was confirmed, revealing a close link between their expressions in EBV+ DLBCL pathogenesis. Remarkably, BZLF1 displayed a negative correlation with CD4 cell counts, and this could be in part justified by the restriction of antigen presentation previously reported. The direct correlation for the late lytic gene BLLF1 and IFNγ in this series could represent a specific response directed towards this antigen. Interleukin 10 transcripts also displayed a positive correlation with lytic expression, indicating that regulatory mechanisms could be also involved on EBV-associated DLBCL pathogenesis in our series. Complete lytic reactivation in EBV-positive tumours could potentially kill EBV-positive malignant cells, providing a tool to promote tumour cell killing mediated by EBV as a complementary treatment strategy., (Copyright © 2017 John Wiley & Sons, Ltd.)

Epstein-Barr Virus (EBV) is present in neoplastic cells of 15% of Asian and Latin-American diffuse large B-cell lymphoma (DLBCL) patients. Even though a tolerogenic microenvironment was recently described in DLBCL, little is known concerning immunomodulatory features induced by EBV. As suggested in Hodgkin lymphoma, EBV-specific cytotoxic T-cells are increased but showing immune exhaustion features. Hence, host immunity suppression may play a critical role in tumor progression. This study aimed to investigate, whether an association between tumor microenvironment features and EBV presence is taking place, and its clinical correlate. The incidence of EBV+DLBCL NOS was 12.6% in this cohort. Cytokine and chemokine transcripts expression and immunophenotype analysis showed that EBV infection was associated with increased gene expression of immunosuppressive cytokine (IL-10) together with increased CD8+ T-cells and granzyme B+ cytotoxic effector cells. However, this specific response coexists with a tolerogenic milieu, by PD-1 expression, in EBV+ and EBV-DLBCL cases. High PD-1+ cell counts, EBV presence and low CCL22 expression were associated with worse survival, supporting our hypothesis that EBV-specific response is mounted locally and its inhibition by, for example PD-1+ cells, may negatively affect outcome. The better understanding of the interplay between lymphoma cells and microenvironment in a viral framework could thereby facilitate the discovery of new targets for innovative anti-lymphoma treatment strategies.

Intestinal intussusception rarely occurs in the adult population and accounts only for 1% to 5% of all the causes of intestinal obstruction. This complication is more frequent in the small bowel and can be due to different aetiologies, including inflammatory, infectious or neoplastic diseases. Malignancies account for 50% to 60% of all cases of colon invagination. The gastrointestinal (GI) tract is the most common site for extra-nodal non-Hodgkin lymphomas (NHL), representing 5% to 20% of all the cases. However, primary NHL of the GI tract is a very infrequent clinic-pathological entity and accounts only for 1% to 4% of all the neoplasms of the GI tract. Primary NHL of the colon is a rare disease and it comprises only 0.2% to 1.2% of all colonic malignancies. Here we describe a case of an AIDS adult patient who developed an intussusception secondary to a primary large B cell lymphoma of the transverse colon. English and Spanish literature was reviewed.

Mycosis fungoides is the most common type of primary cutaneous T cell lymphoma. We have evaluated CDKN2A losses and MYC gains/amplifications by FISH analysis, as well as expression of miR-155 and members of the oncogenic cluster miR-17-92 (miR17, miR18a, miR19b, and miR92a) in MF patients with advanced disease. Formalin-fixed paraffin-embedded skin biopsies from 36 patients at diagnosis, 16 with tumoral MF (T-MF), 13 in histological transformation to a large T cell lymphoma (TR-MF), and 7 cases with folliculotropic variant (F-MF), were studied. Twenty cases showed genomic alterations (GAs): 8 (40 %) had CDKN2A deletion, 7 (35 %) showed MYC gain, and 5 (25 %) exhibited both alterations. GAs were more frequently observed in F-MF (p = 0.004) and TR-MF (p = 0.0001) than T-MF. GAs were significantly higher in cases presenting lesions in head, neck, and lower extremities compared to those observed in trunk and upper extremities (p = 0.03), when ≥25 % neoplastic cells were CD30 positive (p = 0.016) as well as in cases with higher Ki-67 proliferation index (p = 0.003). Patients with GAs showed bad response to treatment (p = 0.02) and short survival (p = 0.04). Furthermore, MF patients showed higher miRNA expression compared to controls (p ≤ 0.0223). T-MF showed higher miR17 and miR-18a expression compared to F-MF and TR-MF (p ≤ 0.0387) while miR19b, miR92a, and miR-155 showed increased levels in F-MF and TR-MF with respect to T-MF (p ≤ 0.0360). Increased expression of miR17 and miR19b in GA group compared to cases without alterations (p ≥ 0.0307) was also detected. Our results add new information about genomic imbalances in MF patients, particularly in F-MF, and extend the present view of miRNA deregulation in this disease.

Mantle cell lymphoma (MCL) is a heterogeneous B-cell lymphoid malignancy where most patients follow an aggressive clinical course whereas others are associated with an indolent performance. SOX4, SOX11, and SOX12 belong to SOXC family of transcription factors involved in embryonic neurogenesis and tissue remodeling. Among them, SOX11 has been found aberrantly expressed in most aggressive MCL patients, being considered a reliable biomarker in the pathology. Several studies have revealed that microRNAs (miRs) from the miR-17-92 cluster are among the most deregulated miRNAs in human cancers, still little is known about this cluster in MCL. In this study we screened the transcriptional profiles of 70 MCL patients for SOXC cluster and miR17, miR18a, miR19b and miR92a, from the miR-17-92 cluster. Gene expression analysis showed higher SOX11 and SOX12 levels compared to SOX4 (P ≤ 0.0026). Moreover we found a negative correlation between the expression of SOX11 and SOX4 (P < 0.0001). miR17-92 cluster analysis showed that miR19b and miR92a exhibited higher levels than miR17 and miR18a (P < 0.0001). Unsupervised hierarchical clustering revealed two subgroups with significant differences in relation to aggressive MCL features, such as blastoid morphological variant (P = 0.0412), nodal presentation (P = 0.0492), CD5(+) (P = 0.0004) and shorter overall survival (P < 0.0001). Together, our findings show for the first time an association between the differential expression profiles of SOXC and miR17-92 clusters in MCL and also relate them to different clinical subtypes of the disease adding new biological information that may contribute to a better understanding of this pathology. © 2016 Wiley Periodicals, Inc., (© 2016 Wiley Periodicals, Inc.)

Objective: To study the main clinical and histopathological features of 12 patients with Hodgkin's lymphoma (HL) diagnosed primarily from bone marrow (BM) involvement., Methods: We included 12 acquired immunodeficiency syndrome (AIDS) patients with HL assisted in the F. J. Muñiz Infectious Diseases Hospital since January 2002 to December 2013. The diagnosis of HL with primary BM involvement in patients was confirmed by clinical, histopathological, and immunohistochemical findings., Results: All patients presented "B" symptoms and pancytopenia. All of them had stage IV neoplasm disease because of BM infiltration. The median of CD4(+) T-cell counts was 114 cells/μL, and mixed cellularity (MC) was the most frequent histopathological subtype of 92% cases., Conclusion: When other causes are excluded, BM biopsy should be performed in AIDS patients with "B" symptoms and pancytopenia to evaluate BM infiltration by atypical lymphocytes.

Introduction Extranodal non-Hodgkin lymphomas (NHLs) are commonly described in patients with acquired immunodeficiency syndrome (AIDS) and are related with an atypical morphology and aggressive clinical course. AIDS-associated lymphomas are characterized by their rapid progression, frequent extranodal manifestations, and poor outcome. Objective The aim of this article is to remake the clinical features of head and neck (HN) NHL in patients with AIDS to facilitate early diagnosis and treatment. Methods We evaluated the epidemiologic, clinical, immunologic, virologic, and histopathologic characteristics of 24 patients with human immunodeficiency virus (HIV)/AIDS with primary HN NHL treated at a single institution between 2002 and 2012. Histopathologic diagnosis was made according to the criteria of the World Health Organization Classification of Tumors of Hematopoietic and Lymphoid Tissues. Additional immunohistochemical stains were applied in all cases. Results Eighteen patients (75%) were men and the median of age was 39 years. The gingiva and the hard palate were the most common sites of the lesions (15 patients, 62.5%). Lactate dehydrogenase levels were elevated in 16 cases (84%). Bone marrow infiltration was detected only in 4 cases (16.6%). The median CD4 T-cell count was 100 cells/µL. According to the histopathologic evaluation, the most common subtype was diffuse large B-cell lymphoma (12 cases, 50%), followed by plasmablastic lymphoma (9 cases, 37.5%) and Burkitt lymphoma (3 cases, 12.5%). Conclusion HN NHL is a severe complication of advanced HIV/AIDS disease. Early diagnosis followed by chemotherapy plus highly active antiretroviral treatment is necessary to improve the prognosis and the survival of these patients.

Primary soft tissue Non-Hodgkin lymphomas are very rare and account only for 0.1 % of the cases. Generally, Non-Hodgkin lymphomas of the soft tissue present as large subcutaneous masses without evidence of nodal or skin involvement. We describe four cases of primary Non-Hodgkin lymphomas of the soft tissue in patients infected with the human immunodeficiency virus. The most common site of involvement was the chest wall in all the patients; histopathological and immunophenotypic examination of the biopsy smears revealed two cases of plasmablastic lymphomas, one Burkitt and one diffuse large B-cell lymphoma. Non-Hodgkin lymphomas should be included in the differential diagnosis of soft tissue masses in human immunodeficiency virus - seropositive patients.

Non-Hodgkin's lymphoma represents 6-10% of pediatric malignancies, and diffuse large B-cell lymphoma (DLBCL) is one of the three major subtypes. The 2008 WHO classification included a new entity, Epstein-Barr virus (EBV)-positive DLBCL of the elderly, affecting patients >50 years. It has been demonstrated that EBV may play a role in tumor microenvironment composition, disturbing antitumor immune response and disease progression. As most studies were performed in adults, our aim was to assess EBV presence and latency pattern, as well as T-cell microenvironment in a pediatric DLBCL series of Argentina. The study was conducted on formalin-fixed paraffin-embedded biopsies from 25 DLBCL patients. EBV-encoded small nuclear early regions (EBERs) expression was performed by in situ hybridization, whereas EBV gene expression was analyzed using real-time PCR. Epstein-Barr virus latent membrane proteins (LMP)1, LMP2A, CD3, CD4, CD8 and Foxp3 expression were assessed by immunohistochemistry (IHC). Forty percent of cases showed EBV expression, with a significantly higher incidence among patients <10 years (p = 0.018), and with immunosuppressed (p = 0.023). T-cell subsets were not altered by EBV presence. Full EBV latency antigen expression (latency type III) was the most frequently pattern observed, together with BZLF1 lytic gene expression. One patient showed II-like pattern (LMP1 without LMP2A expression). Based exclusively on IHC, some patients showed latency II/III (EBERs and LMP1 expression) or I (EBERs only). These findings suggest that EBV association in our series was higher than the previously demonstrated for elderly DLBCL and that EBV latency pattern could be more complex from those previously observed. Therefore, EBV could be an important cofactor in pediatric DLBCL lymphomagenesis., (Copyright © 2012 UICC.)

Introduction: Extranodal non-Hodgkin lymphoma (NHL) were commonly described in AIDS patients and are related with an atypical morphology and aggressive clinical course., Materials and Methods: In this single institutional study we evaluated the epidemiological, clinical, immunological, virological, histopathological and the outcome of eleven HIV/AIDS patients with oral cavity lymphomas (OCL)., Results: Nine were males and seven intravenous drug abusers. The median of age was 33 years and the median of CD4 T cell counts at the time of diagnosis was 97 cell/µL. The majority of tumors presented as large and ulcerated masses involving the gingiva, the palate and the jaw. Six of these tumors were diffuse large B-cell lymphomas (DLBCL); three were Burkitt's lymphomas and the final case was a plasmablastic lymphoma. An association with Epstein-Barr virus (EBV) was found in three of the ten tested cases by in situ hybridization (EBER 1 and 2 probes) and immunohistochemistry (LMP-1). Human herpes virus-8 (HHV-8) was detected by polymerase chain reaction (PCR) in only one neoplasm. Six patients died without specific treatment; four received chemotherapy and highly active antiretroviral therapy (HAART) and three of them presented a prolonged survival., Discussion: Combination of HAART and chemotherapy should modify the poor prognosis of AIDS patients with OCL.

Cutaneous B cell lymphoma (CBCL) is a lymphoproliferative disorder of neoplastic B cell of the skin with a wide range of clinical manifestations. Commonly, the clinical features of CBCL are plaques, nodules, or ulcerative lesions. Skin is one of the common sites for extra-nodal lymphomas in patients with AIDS and B cell type is less common than T cell type. Only recently, the existence of B cell lymphomas presenting clinically in the skin without evidence of extra-cutaneous involvement has been accepted as primary CBCL. Here, we are presenting 5 patients with cutaneous involvement in the setting of HIV/AIDS disease. Two of them were primary cutaneous non-Hodgkin lymphomas. All were CBCL; 3 were immunoblastic, 1 was plasmablastic, and the other was a Burkitt lymphoma. We analyzed the epidemiological, clinical, virological, and immunological characteristics of this group of patients.

Non-Hodgkin lymphomas (NHL) of the B-cell type are the second most common neoplasm among patients with human immunodeficiency virus (HIV) infection and AIDS. Here, we evaluated 48 cases of AIDS-related lymphomas (ARL) diagnosed at the Histopathological Division of the Instituto de Investigaciones Hematológicas of the National Academy of Medicine. Five were females and 43 were males with a median of age of 37 years at the time of the diagnosis. Micrometer sections were prepared and stained with hematoxilin-eosin; immunohistochemical examination for the presence of Epstein-Barr virus (EBV) was carried out in 48/48 cases. Additionally, biotinilated oligonucleotides were used to determine the presence of DNA of the Human Herpes virus type-8 (HHV-8) in 14/14 biopsy smears corresponding to plasmablastic lymphomas (PL). All were fenotype B cell lymphomas with an aggressive course and advanced neoplasm disease at the time of diagnosis. Virological findings showed the strong association between EBV and AIDS-related NHL. According to the histopathological subtype, the EBV genome was detected in 16/21 (76%) diffuse large B cell lymphomas, 1/3 Burkitt lymphoma and 3/4 (75%) of primary central nervous system lymphomas. Globally, EBV genome was detected in 20/28 NHL of this series. Detection of HHV-8 was negative in all cases of PL. Hodgkin lymphoma were more frequent in males 18/20 (90%), with an aggressive clinical course and a significant predominance of the subtypes associated with worse prognosis (90% of cases). We detected a significant association between EBV and HL (90% of cases). We consider that all cases of AIDS related lymphomas should be assessed for the presence of EBV because its presence may play a role in the prognosis.

Mantle cell lymphoma (MCL) is a well defined lymphoid neoplasm genetically characterized by the t(11;14)(q13;q32). Telomeres play an essential role in preserving chromosomal integrity and genomic stability; their shortening can lead to telomere dysfunction and chromosomal instability, a critical factor in cancer development. In this study, telomere length (TL) measured by terminal restriction fragments (TRF) assay in DNA samples of tumor cells from 20 patients with MCL was evaluated. Results were correlated with clinical, morphologic and cytogenetic characteristics. In all cases, the presence of the CCND1/IGH@ rearrangement was confirmed by fluorescence in situ hybridization and/or PCR analysis. TL in total MCL patients revealed a mean TRF value (4.51 +/- 0.79 kb) significantly shorter than those observed in controls (7.49 +/- 1.94 kb) (P < 0.001); 30% of patients had TL shorter than 4.0 kb. TRF length was not associated with patients age (P = 0.07; r = 0.17) nor with sex (females: 4.33 +/- 0.51 kb and males: 4.57 +/- 0.85 kb; P = 0.63). No significant differences were found between patients studied at diagnosis (13) (4.44 +/- 0.81 kb) respect to those analyzed at relapse (7) (4.63 +/- 0.82 kb) (P = 0.53). In addition, we compared patients with (4.84 +/- 1.09 kb) and without (4.40 +/- 0.68 kb) complex karyotypes (P = 0.45) and cases with typical morphology (4.48 +/- 0.79 kb) vs. blastoid variant (4.63 +/- 1.04 kb) (P = 0.83), and no significant differences between them were found. Although the number of cases of our series is not large, our results showed that TL reduction in MCL is independent of the clinical characteristics, morphology and karyotype.

Plasmablastic lymphoma is a rare and a relatively new entity that was first described in the jaws and the oral cavity of HIV-AIDS patients. We report a case of plasmablastic lymphoma involving the liver in an AIDS patient. Plasmablastic lymphoma is considered a diffuse large B-cell lymphoma with a unique phenotype and predilection for the oral cavity. The case presented had a unique hepatic lesion, localized in the left lobe of the liver. Diagnosis was confirmed by hepatic biopsy guided by Computerized Tomography scan and histopathology. The smears showed a dense infiltrate composed by atypical lymphocytes with numerous plasmocytes expressing the plasma cell markers MUM-1 and CD138 and negative for the B-cell markers CD3, CD20 and CD45. Immunohistochemical and in situ hybridization revealed the Epstein-Barr virus genome in the atypical cells. Polymerase chain reaction was negative for HHV-8 RNA.

Smooth muscle neoplasms are more frequent in human immunodeficiency infected children than in HIV seropositive adults. Endobronchial leiomyoma is a rare benign tumor in HIV infected adult patients. Epstein-Barr virus (EBV) has been implicated in the pathogenesis of these tumors. Here we describe an adult patient with HIV infection with atelectasis of the left upper pulmonary lobe as the first clinical expression of an intrabronchial leiomyoma. In this case, we can not show the association with EBV. Our report suggests that smooth muscle tumors as leiomyoma should be included in the differential diagnosis of endobronchial masses in AIDS patients.

Adult intussusception is rare. Here, we describe a case of an AIDS adult patient who developed an ileocolic intussusception secondary to a large B cell lymphoma of the cecum. Surgical findings included the ileon free of the tumor and invaginated within the cecum with infiltrating neoplasm. Surgical treatment included the resection of the right hemicolon because of the tumor, located in the cecum, causing intussusception. The English and Spanish literature is reviewed.

A retrospective study was conducted of extranodal oral Non-Hodgkin's Lymphomas diagnosed at the Surgical Pathology Laboratory of the School of Dentistry at Buenos Aires University, Argentina, between 1985 and 2004. The 40 cases found represent 0.2% of the oral biopsies diagnosed during that time and 4.6% of malignant neoplasias. Overall mean age of patients was 49.4 years, and frequency was greater in males. 80% affected soft tissues. Prevalent location was gingival, followed by palate. Intraosseous cases were more frequent in mandible (75%) than in upper maxilla. 100% of the cases were phenotype B, with a higher frequency of high-grade aggressiveness. The most common histological type was Diffuse Large Cell Lymphoma. 60% of the Plasmablastic Lymphomas in the series came from HIV+ patients. Evolution time prior to consultation was 1 to 3 months in 57.7% of the cases.

Non-Hodgkin's lymphoma of B-cell type is the second most common neoplasm after Kaposi's sarcoma, among patients with human immunodeficiency virus infection. Most non-Hodgkin's lymphoma cases that are associated with acquired immunodeficiency syndrome involve extranodal sites, especially the digestive tract and the central nervous system. We report a case of primary lymphoma of the duodenum in a patient with AIDS. Upper gastrointestinal endoscopy revealed pseudopolypoid masses found in the second portion of the duodenum. A complete diagnostic study including histological, immunohistochemical and virological analyses showed high-grade B-cell Burkitt's lymphoma. The Epstein-Barr virus genome was detected in biopsies by immunohistochemical and in situ hybridization.