Necrotizing sialometaplasia of the palate associated with angiocentric T-cell lymphoma.

In this article we present 2 cases of necrotizing sialometaplasia (NS) associated with angiocentric lymphoma of the midline. Immunohistochemical analysis confirmed a T-cell origin, and in situ hybridization in one case revealed its relationship to Epstein-Barr virus. These findings suggest that vascular occlusion by the neoplastic cells produces ischemia, which leads to local infarction contributing to the salivary gland lesion. To our knowledge, the association between angiocentric lymphoma and NS has been previously reported in only one instance, and we suggest that this particular type of lymphoma should be added to the list of related conditions for NS.

Primary natural killer/T-cell lymphomas of the oral cavity are aggressive neoplasms.

Thirty-four cases of primary non-Hodgkin's lymphoma of the oral cavity were investigated for their clinical findings, histopathological features, immunophenotypes and association with Epstein-Barr virus (EBV). Four cases (12%) were natural killer/T-cell lymphomas, 3 (9%) were T-cell lymphomas and 27 (79%) were B-cell lymphomas. Compared with T- and B-cell lymphomas, NK/T-cell lymphomas had a male predominance (M:F 4:0), and most presented as ulceration of the palate and/or maxillary gingiva. Histologically, the lesions showed diffuse infiltration of medium-sized or large lymphoid tumour cells. Angiocentricity and/or angioinvasion were found in all 4 cases. The immunophenotypes of the NK/T-cell lymphomas were CD3+, CD43+, CD45RO+, CD56+ and TIA-1+. EBV was detected in 2 NK/T-cell lymphomas by in situ hybridization (ISH) and polymerase chain reaction (PCR) methods, and was not detected in T- and B-cell lymphomas. The survival rate of patients with NK/T-cell lymphoma was zero, but the survival rates for patients with T-cell and B-cell lymphomas were 67% and 38%, respectively. It appears that NK/T-cell lymphomas of the oral cavity have a predilection for originating in the palate and maxillary gingiva and are aggressive neoplasms. EBV positivity might be associated with more aggressive behaviour.

Extranodal NK/T-cell lymphoma mimicking cellulitis.

NK/T-cell lymphoma is difficult to diagnose because there is no characteristic cytology to help the diagnosis in tissue sections, particularly when there is polymorphic cellular infiltration in the early stage of the disease. However, the nasal type of extranodal NK/T-cell lymphoma has a characteristic histologic pattern, which is angiocentric, angioinvasive and angiodestructive. Therefore, many cases of this tumor may show extensive necrosis that mimics infectious process. Furthermore, because the immunosuppressive status of these patients, they may, in fact, have superimposed infections. We are reporting a case that presented as cellulitis and only after careful examination with immunohistochemistry that a correct diagnosis of extranodal NK/T-cell lymphoma, nasal type, was established. Since this lymphoma is incurable and immunophenotyping is instrumental for the diagnosis and prediction of the prognosis, a high index of suspicion for this tumor is needed when an angiocentric lesion is found in the midline of the head and neck region, and a thorough immunohistological study should always be conducted in these cases.

Synergistic antiviral effect of PEG-asparaginase (ONCASPAR), with protease inhibitor alone and in combination with RT inhibitors against HIV-1 infected T-cells: a model of HIV-1-induced T-cell lymphoma.

We evaluated the anti-HIV-1 activity of the T-cell-specific protein inhibitor PEG-asparaginase (PEG-ASNase) in human HIV-1-infected T-cells. We further examined the drug synergism between PEG-ASNase and the protease inhibitor Saquinavir (SAQ), both alone and in combination with nucleoside analog reverse transcriptase inhibitors (NRTI). Our drug synergism studies served as a model for an HIV-induced T-cell lymphoma. Phytohemagglutinin [PHA(+)] stimulated T-cells were infected with HIV-1 and then treated with one or more drugs 90 minutes from the viral exposure. To measure inhibition of viral replication, we examined HIV-1 RT and HIV-1 RNA in the supernatant and intracellularly on day 7 post-infection and drug treatment. Last, we examined the effect of administering drugs immediately after HIV-1 infection of T-cells to simulate treatment after an accidental exposure to the virus. PEG-ASNase, even when used alone, has anti-HIV-1 activity in PHA(+)-stimulated T-cells due to inhibition of protein synthesis. When the drug was used with SAQ, the combination was synergistic in inhibiting HIV-1 RT and RNA in the supernatant and intracellularly by 2.5 log10 in comparison with controls. PEG-ASNase and SAQ were even more effective in inhibiting HIV-1 replication when combined with the NRTI inhibitors azidothymidine (AZT) and (-)-beta-2',3'-dideoxy-3'-thiacytidine (3TC, lamivudine). The addition of ribonucleotide reductase inhibitor, 2-methyl-1H-isoindole-1,3-dione (MISID), further potentiated the antiviral effect of the regimen. HIV-1 RT and RNA analyses showed that the administration of the PEG-ASNase + SAQ drug combination immediately following exposure to HIV-1 completely inhibited the infection of T-cells in our in vitro T-cell model. From these results we conclude that PEG-ASNase is a valuable T-cell-specific protein inhibitor against HIV-1 infection, when used singly or in combination with a protease inhibitor, an RT inhibitor and an RR inhibitor. Since PEG-ASNase is a drug of choice for the treatment of T-cell lymphomas, a combination regimen containing PEG-ASNase could be very effective in the treatment of HIV-1-induced T-cell lymphoma and possibly AIDS. Future studies are needed in HIV-infected and/or HIV-induced T-cell lymphoma patients to investigate these findings.

A familial T-cell lymphoma with gamma delta phenotype and an original location. Possible role of chronic Epstein-Barr virus infection.

BACKGROUND: We describe a familial lymphoproliferative syndrome associated with Epstein-Barr Virus (EBV) infection and the gamma delta phenotype. METHODS: We reviewed clinical, pathologic, immunologic, and virologic findings in a nonconsanguineous French family, collected over a 13-year period. Specimens from the father (autopsy), son (liver, lymph nodes, and pericardial effusion), and daughter (skin, liver, and digestive tract) were studied with conventional histologic and immunohistochemical techniques. Anti-EBV latent membrane protein (LMP) antibody and T-cell receptor (TCR) gene rearrangements were also studied in the daughter. RESULTS: The father and daughter had similar clinical and histologic features with maxilofacial, nasal, laryngeal, skin, lung, gastrointestinal, and liver involvement by a high grade large cell angiocentric T-cell lymphoma. The gamma delta phenotype and clonal rearrangement were identified in the daughter's tumor. At the time of his death from pericarditis, the son had a 5-year history of a recurrent hemophagocytic syndrome and lymphadenopathy. Chronic EBV infection was found in each case. EBV infection of the son was diagnosed by means of serologic tests and detection of the EBV genome in circulating lymphocytes, and in the father and daughter by use of an anti-LMP antibody. Its pathologic role is discussed. CONCLUSION: This familial T-cell lymphoma syndrome associated with the gamma delta phenotype and an unusual location is an original clinical entity. Chronic EBV infection was present in each case, but its precise role remains to be determined.

Real-time PCR for quantification of human herpesvirus 6 DNA from lymph nodes and saliva.

A real-time quantitative PCR assay has been developed to measure human herpesvirus 6 (HHV-6) DNA in biological specimens. The assay sensitivity was 10 copies of DNA per well, with a linear dynamic range of 10 to 10(7) copies of HHV-6 DNA. Intra- and interassay variations were, respectively, 0.88 and 0.8% for samples containing 10(2) DNA copies, 0.99 and 0.96% for samples containing 10(4) copies, and 0.76 and 0.9% for samples containing 10(6) copies. Among 34 saliva samples from healthy subjects, 26 were found to contain HHV-6 DNA (76.5%; median, 23,870 copies/ml), and following a single freeze-thaw cycle, 25 of the same samples were found to be positive for HHV-6 DNA, although at a statistically significantly lower concentration (median, 3,497 copies/ml). The assay enabled detection of HHV-6 DNA in lymph node biopsies from patients with Hodgkin's disease (HD) (13 of 37 patients [35.1%]), B-cell neoplasms (8 of 36 patients [22.2%]), and T- or NK-cell neoplasms (3 of 13 patients [23.1%]), with concentrations ranging from 100 to 864,640 HHV-6 copies per microg of DNA (HHV-6B being found in every case except two). All HD patients infected with HHV-6 presented clinically with the nodular sclerosis subtype of HD. The real-time quantitative PCR assay developed here was simple to perform and was sensitive over a wide range of HHV-6 concentrations. It therefore appears to be of potential value in clinical investigation or diagnosis of HHV-6 infection.

Viral lesions of the mouth in HIV-infected patients.

Viral lesions of the mouth in patients with HIV infection are common and these diseases any be a marker for HIV and disease progression. We review the spectrum of oral viral manifestations and discuss treatment modalities. The most common Epstein-Barr virus (EBV)-induced disorder in HIV-infected patients is oral hairy leukoplakia. EBV-related oral B-cell and T-cell lymphoma in AIDS patients has been described repeatedly. Herpes virus type 1 and rarely type 2 may lead to painful and resistant oral ulcers, and systemic treatment with acyclovir, valaciclovir or famciclovir is indicated. In acyclovir-resistant cases foscarnet is the treatment of choice. In recent years it has been documented that Kaposi's sarcoma, which often affects oral mucosa, is probably induced by herpesvirus type 8. Cytomegalovirus was found in 53% of cases with herpesviridae-induced mucosal ulcers as the only ulcerogenic viral agent in AIDS patients. In severe cytomegalovirus infection treatment with ganciclovir is helpful. Viral warts induced by different HPV may occur in the mouth. Several physical treatment modalities are possible in the oral mucosa. In AIDS patients mollusca contagiosa may occur as large and atypical lesions in the face and lips and rarely in the oral cavity. Cryotherapy is a bloodless treatment in such patients.