Mucosa-associated lymhpoid tissue (MALT) lymphoma of the jejunum and Helicobacter pylori--chance association?

Helicobacter pylori have been causally linked to primary gastric B-cell lymphoma of the mucosa-associated lymphoid tissue (MALT) type. Antibiotic therapy to eradicate H. pylori has been shown to induce remission of such lymphoma. We report a case of primary B-cell MALT lymphoma of the jejunum associated with H. pylori. The literature of intestinal MALT lymphoma is reviewed.

Epstein-Barr virus-associated smooth muscle tumors in ataxia-telangiectasia: a case report and review.

Chromosomal breakage syndromes, including ataxia-telangiectasia (AT), are autosomal recessive disorders in which DNA repair mechanisms are defective resulting in chromosomal instability. Affected individuals are at high risk for developing malignancy because of the widespread resulting cellular effects. One such effect, severe immunosuppression, can permit virally mediated neoplasms to manifest, similar to those seen in acquired immunodeficiency syndrome (AIDS), congenital immune deficiency syndromes, and posttransplant populations. Epstein-Barr virus (EBV) is a common viral agent known to be associated with lymphoid, epithelial, and smooth muscle malignancies in such patients. Although smooth muscle tumors have been reported in patients with AT, their association with EBV has not been evaluated. We present a case of EBV-associated laryngeal leiomyosarcoma and jejunal cellular leiomyoma in a child with AT. This case suggests that the development of neoplasia in patients with chromosomal breakage syndromes may be related to the immunosuppressive consequences of these diseases, and searching for infectious causes (such as EBV) is important.

[Primary digestive tract Kaposi sarcoma with idiopathic CD4+ lymphocytopenia, HIV negative, HHV8 positive]. / Sarcome de Kaposi digestif primitif avec lymphocytopénie CD4 idiopathique, VIH négatif, HHV8 positif.

A 52-year-old Tunisian patient had fever, impaired health and several opportunistic infections (Campylobacter jejuni, Mycobacterium hominis, Herpes virus, Giardia intestinalis, Vibrio metschnikovii). Lymphocytopenia was noted (348/mm3; CD4+: 2.2%; CD4+/CD8+: 0.1). Polymerase chain rection search for HIV was negative in serum and in tumor tissue. Diagnosis of primary digestive Kaposi sarcoma was established at autopsy due to the deep location of the lesions. There was an ulcerofungating tumor spreading over 1.3 m of the duodenojejunum. This is the fourth reported case of CD4+ lymphocytopenia, a new and very rare immunodeficiency syndrome recently defined by the Centers for Disease Control. We detected human herpes virus 8 by immunohistochemistry of tumor tissue. Human herpes virus 8 is implicated in the pathogenesis of Kaposi sarcoma.

Primary anaplastic large cell lymphoma of the small intestine.

We describe the clinicopathologic, immunophenotypic, and molecular findings in 4 cases of anaplastic large cell lymphoma (ALCL) arising in the small intestine. All patients were men with acute symptoms of gastrointestinal tract obstruction. The clinical preoperative diagnosis was gastrointestinal carcinoma in 3 cases, and pancreatic carcinoma in 1 case. Histologic examination revealed cohesive aggregates of neoplastic cells, with multiple vesicular nuclei, prominent nucleoli, and abundant amphophilic cytoplasm. There was no clinical or histopathologic evidence of enteropathy. All cases were CD30+, and all showed evidence of T-cell lineage with cytotoxic potential by expression of CD3, CD43, or CD45RO; T-cell intracellular antigen-1; or perforin. One tumor showed p80 and anaplastic lymphoma kinase (ALK) overexpression corroborated by the presence of the t(2:5). One tumor expressed Epstein-Barr virus latent membrane protein. In all cases, the tumor cells were negative for CD20, CD15, CD56, and cytokeratin. Polymerase chain reaction revealed clonal rearrangements of the T-cell receptor gamma-chain gene, without evidence of immunoglobulin heavy-chain gene rearrangement. The diagnosis of primary bowel ALCL is facilitated by immunophenotypic and molecular studies. With 24 months of clinical follow-up, only the patient with the t(2:5)-positive tumor is alive and free of disease, suggesting that p80/ALK overexpression may be a good prognostic indicator.

Gastric lymphoepithelioma-like carcinoma and jejunal B-cell MALT lymphoma with large cell transformation. Demonstration of EBV with identical LMP gene deletions in the carcinoma and large cell lymphoma.

The authors describe a patient with gastric lymphoepithelioma-like carcinoma (LELC) and jejunal low grade B-cell lymphoma of mucosa-associated lymphoid tissue (MALT) with histologic transformation to large cell lymphoma. In situ hybridization studies for Epstein-Barr virus (EBV) demonstrated abundant EBV RNA (EBER) within the neoplastic cells of the gastric LELC and the jejunal large cell lymphoma. The low grade MALT lymphoma was EBER negative. Polymerase chain reaction (PCR) studies confirmed the in situ hybridization results, and demonstrated a 30 base pair deletion in the 3' end of the latent membrane protein gene in both the gastric LELC and the jejunal large cell lymphoma. These results suggest that the same viral strain infected both the stomach and jejunal tumors. In addition, the finding of EBV in the large cell lymphoma, but not the low grade component suggests that EBV may have played a role in large cell transformation.