Thalassemia Major Terminating in a Non-hodgkin B-cell Lymphoma: Report of a Case

A large noncleaved diffuse follicular center cell lymphoma occurring in an 11-year-old child with homozygous beta thalassemia is described. The possible relationship between numerous blood transfusions during a 10-year period and the occurrence of a B-cell lymphoma is discussed.

Effects of a Single Dose of Rabbit Anti-mouse Lymphocyte Serum on Tumors Induced in Mice by 7,12-Dimethylbenz (a) anthracene Given at Birth

The effects of ALS (anti-lymphocyte serum) and NRS (normal rabbit serum) treatments on the development of malignant lymphoma, lung, subcutaneous and skin tumors induced in mice by 7,12-dimethylbenz (a) anthracene (DMBA) are described. Groups of Charles-River mice, injected at birth with a dose of 100 μg of DMBA, received a single injection of ALS or NRS at the same time as DMBA administration or 10, 20, 30, 40 and 50 days after birth. Incidence, latency, histology and spread of the tumors were studied in all groups. It was found that both ALS and NRS increased tumor incidence and shortened their latency period. Malignant lymphomas were the main tumors whose latency was shortened either by ALS or NRS treatment. In addition ALS treatment apparently increased dissemination of DMBA induced lymphoma in bone marrow.

Secondary Immune Response anti Sheep Bed Blood Cells in Swiss Mice Injected at Birth with a Single Dose of 7,12-dimethylbenz (a) anthracene

It was previously reported that a neonatal injection of 7,12-dimethylbenz (a) anthracene (DMBA) in mice induces a reduction both of the primary immune response to sheep red blood cells (SRBC) and, later in life, of delayed hypersensitivity. In this study we investigated the secondary immune response to SRBC in Swiss mice injected at birth with 100 μg of DMBA. Groups of DMBA treated and control animals were sacrificed respectively 30, 50, 75, 100, 150 and 200 days after treatment with the carcinogen. They were given a priming i.p. injection of 4 × 108 SRBC in saline 20 days before sacrifice and a booster of SRBC 48 h before killing. The numbers of indirect spleen plaque forming cells and the hemagglutinin titers after reduction with 2-mercaptoethanol were determined at the time of sacrifice. It has been constantly found that animals given carcinogen at birth show a depressed secondary response, regardless of the presence of tumors. The present results fit well with our previously reported observations showing a constantly depressed immune response after neonatal DMBA treatment, and further suggest the existence of a relationship between immunodepression and the high rate of tumors that DMBA induces. The results are also discussed in relation to others studies indicating a direct action of leukemia viruses on undifferentiated B-lymphocytes of marrow origin, in view of the suggested activation of a latent lymphoma virus by DMBA.

Fibrosarcoma of the Thymic Region. A Case Report

Fibrosarcoma of the mediastinum is an unusual tumor and only few cases have been reported. We describe the clinical and pathologic findings of a case of mediastinal mass in a 34 year old woman. The histologic, histochemical, immunocytochemical and ultrastructural features of the tumor were consistent with a diagnosis of fibrosarcoma. Furthermore, the tumor displayed evidence of close relations with the thymus capsule; the possibility that it may arise from the thymic stroma is considered. The differential diagnosis of spindle cell tumors of the mediastinum is also discussed.

Involvement of the Bone Marrow by Non-Hodgkin's Lymphomas: Incidence, Histology and Pathologic Correlations

The Lukes and Collins system of classification was applied to 151 cases of non-Hodgkin's lymphoma who had bone marrow biopsies taken immediately after histologic diagnosis. Incidence and histologic pattern of bone marrow involvement at the time of initial diagnosis were determined for each subtype of lymphoma. Thirty-three patients (21.8 %) had bone marrow involvement. The frequency of bone marrow involvement was high for undefined and convoluted lymphocyte lymphomas (66.6 %) and low to intermediate for follicular centre cell (20.3 %) and small lymphocyte lymphomas (20.0 %). Within the FCC lymphomas the non-cleaved cell type had a higher incidence of marrow involvement than the cleaved cell type (41.6 % vs 8.9 %). The follicular and diffuse histologic patterns in the diagnostic node did influence the incidence of marrow invasion in the non-cleaved cell type (75 % vs 25 %). A low incidence of marrow involvement was observed for the immunoblastic lymphomas (14.2 %); evidence of marrow infiltration was never observed in patients with true histiocytic lymphoma.

Peripheral T Cell Lymphoma in Adults: Morphological and Phenotypical Study of Four Cases

In the present study we investigated the lymph node morphology and distribution of cell surface phenotypes in four cases of adult peripheral T cell lymphoma. Histologically, the tumors were classified as T zone lymphoma, T cell lymphoma with large multilobated nuclei and T cell immunoblastic sarcoma. In the T zone lymphoma the neoplastic lymphocytes were E+ (90 %) and exhibited intensive focal staining for acid phosphatase (93 %) and acid esterase (92 %); the phenotype distribution revealed low expression of the T-3 antigen (49 %), selective expression of the T-4 antigen (72 %) and poor expression of T-6 (10 %) and T-10 antigens (22 %). Some of these features are present in normal and in neoplastic immature T cells. In the remaining three cases the majority of lymph node cells were E+ (59–75 %), T-3+ (67–80 %) and T-8+ (43–55 %). A distinctive feature of the T cell immunoblastic sarcoma was the presence of high percentages of DR+ cells (62 %; 63 %). Thus our results indicate that the morphological heterogeneity of peripheral T cell lymphoma is also paralleled by a variety of surface phenotypes and that phenotype studies may provide a useful contribution to identification and accurate classification of peripheral T cell neoplasms.

Primary Malignant Tumors of the Thyroid Gland. Histology, Age and Sex Distribution and Pathologic Correlations in 139 Cases

The classification proposed by Woolner et al. (1961, 1971) has been applied to 139 cases of primary malignant tumors of the thyroid gland diagnosed in one of the largest hospitals of Rome, Italy, over a period of 5 years, from 1977 to 1981. These cases come from 1418 patients with enlargement of the thyroid surgically treated at the 5th Surgical Clinic of the University of Rome. All the histologic slides were re-examined, and the pathology records were re-evaluated. Of these tumors, 56.8% were papillary, 30.9% follicular, 9.3% anaplastic or undifferentiated, and 2.1% medullary. There was a female predominance in all age groups and for all types of tumors, reflecting a total female to male ratio of 1.9:1. Papillary carcinoma occurred most commonly in young and young-adult patients, follicular in the middle-age group, and anaplastic in the elderly. The extent of the primary tumor, the presence of regional metastases, and the association with other thyroid nonneoplastic diseases such as lymphocytic and Hashimoto's thyroiditis, and nontoxic and toxic goiter were also recorded. Multicentric rumors were found in 38.9% of cases principally represented by papillary carcinomas. Regional lymph node metastases were observed mainly in young patients, and no correlation was found between thyroid cancer incidence and other nonneoplastic thyroid diseases.

Effects of Repeated Injections of Rabbit Anti-mouse Lymphocyte Serum on Tumors Induced in Mice by 7,12-dimethylbenz (a) anthracene Given at Birth

The present paper describes the effects of repeated administration of rabbit anti-mouse lymphocyte serum (ALS) or normal rabbit serum (NRS) on tumors induced in Charles–River mice by 7,12-dimethylbenz (a) anthracene (DMBA) given at birth. ALS or NRS were given at the same time of DMBA administration and subsequently at weekly intervals for the first 10 weeks of life or at daily intervals for 7 days during the first, second, third or fourth week of life. Incidence, latency, diffusion and histology of the tumors were studied. It was found that either chronic administration of ALS or treatment of very young mice with the serum, greatly reduced the mean survival time of mice, markedly increased the number of tumor bearing mice and the incidence of all histological types of tumors, and decreased their latency period. Administration of ALS in the other experimental groups gave results essentially similar to those observed in DMBA control and NRS treated mice.

Expression of TCL1 and CD27 in primary cutaneous B-cell lymphomas

AIMS

To investigate by immunohistochemical analysis the expression of the TCL1 oncogene product and of CD27 in 25 cases of primary cutaneous B-cell lymphomas (PCBCL) classified according to the World Health Organization-European Organization for Research and Treatment of Cancer classification of cutaneous lymphomas. In B-cell ontogenesis TCL1 is mainly expressed by 'naive' B lymphocytes and by a subset of germinal centre B cells, whereas CD27 is expressed by a subset of germinal centre B cells, 'memory' B lymphocytes and plasma cells, suggesting that their expression in physiological conditions is mutually exclusive.

METHODS AND RESULTS

Overall, TCL1 was expressed in 5/25 cases (20%) and CD27 in 15/25 cases (60%). Furthermore, 7/25 cases (28%) were TCL1- and CD27- and 2/25 cases (8%) were TCL1+ and CD27+. In particular, primary cutaneous follicle-centre lymphomas (10 cases) showed a variable expression of both TCL1 and CD27, whereas primary cutaneous marginal-zone B-cell lymphomas (eight cases) showed, with the exception of a single case, a definite CD27+/TCL1- profile.

CONCLUSIONS

These findings indicate: (i) the TCL1 oncogene product is uncommonly expressed in PCBCL (20% of cases, mainly of the follicle-centre subtype); (ii) in contrast, CD27 is often expressed in PCBCL (60% of cases), mainly of the marginal-zone subtype; (iii) the coexpression of TCL1 and CD27 may be seldom observed in PCBCL (8% of cases); (iv) PCBCL does not seem to show, in terms of either TCL1 or CD27 expression, significant differences compared with its systemic counterparts.

[The Haemolymphopathology Italian Group (H.I.G.): an essential resource for the new technical and organization problems troubling modern haemolymphopathology diagnostics]

Recently, many progresses have been recorded in the molecular and histogenetic characterization of the haematopoietic and lymphoid tumours, resulting in important classifying changes. As a consequence, the exact definition of lymphoma subtype requires an integration between traditional morphologic "expertise" and several bio-functional data obtained from advanced and complex ancillary techniques (immunohistochemistry, molecular biology and cytogenetics). At the same time, the data provided by gene expression profiling studies are going to deeply modify the therapies in haematological cancers. These studies are expected to allow the achievement of single-patient-tailored genic therapy; for this reason it is necessary to get biological samples of good quality. Indeed, while these progresses contribute to highlight the pathologist's diagnostic role, they should make us reflect on the state of the art of the Italian haemolymphopathology diagnostics and on its ability to cope up with the new challanges. The aim of this article is to outline a realistic picture of the present condition, and to explain the reasons for setting up, inside SIAPEC-IAP, the Haemolymphopathology Italian Group (H.I.G.). The purpose of H.I.G. will be twofold: first of all, scheduling of a series of projects so as to the haemolymphopathological diagnostic standardization; secondly, building a national network among all the pathologists involved in this exciting and complex field of the anatomic pathology.

p53 over-expression identifies a subset of nodal peripheral T-cell lymphomas with a distinctive biological profile and poor clinical outcome

Peripheral T-cell lymphomas (PTCL) are usually characterized by aggressive clinical behaviour and poor clinical outcome, but their biological background has not been extensively investigated to date, due to their low incidence, about 10% of all non-Hodgkin's lymphoma cases in Western countries, and also to the paucity of specific molecular-genetic abnormalities. Neverthless, there is increasing biological and clinical evidence that primary nodal PTCL should be considered separately from extra-nodal cases, but little is known about biological factors of possible clinical and prognostic impact. This immunohistochemical study has analysed the expression of p53, Mdm2, p21(WAF1), BCL-2 and p-glycoprotein (MDR-1 gene product) in a series of 45 cases of nodal peripheral T-cell lymphomas (PTCL) with 'high-grade' histology. The immunohistochemical findings were then correlated with proliferative activity and clinical outcome. p53 was over-expressed in 13 cases (28.9%). p53 positive cases showed significantly higher proliferative activity (p<0.01), more frequent expression of Bcl-2 (p<0.01) and less frequent expression of p21(WAF1) than p53 negative cases. Mdm2 and p-glycoprotein were expressed in 4/13 (30.8%) and 8/13 (61.5%) p53 positive cases respectively, and in none (0%) of the p53 negative cases (p<0.01). Analysis of the survival curves showed that p53 positive cases were associated with a significantly poorer clinical outcome than p53 negative cases, in terms of both overall survival (p=0.0032) and event-free survival (p=0.0004). Furthermore, multivariate analysis showed that p53 expression was the most important independent prognostic variable. These findings indicate that p53 over-expression identifies a subset of nodal PTCL cases with a distinctive biological profile (higher proliferative activity, less frequent expression of p21(WAF1) and more frequent expression of Bcl-2, Mdm2 and p-glycoprotein than p53 negative cases) and poor clinical outcome. The immunohistochemical analysis of p53 expression is a simple, rapid and low-cost method which may provide information of potential clinical and prognostic value in nodal peripheral T-cell lymphomas.

Laminin alpha2 chain (merosin M chain) distribution and VEGF, FGF(2), and TGFbeta1 gene expression in angiogenesis of supraglottic, lung, and breast carcinomas

The prognostic significance of vessel quantification in human solid tumours is still debated, due to the presence of multiple factors modulating neoangiogenesis and the invasiveness of neoplastic cells. This study examined ten supraglottic squamous carcinomas, ten non-small cell lung carcinomas (three squamous, five bronchioloalveolar, two adenocarcinomas), and nine classic (NOS) invasive ductal breast carcinomas. The properties studied in these tumours were vascularity; the immunohistochemical distribution of adhesion molecules such as alpha2beta1, alpha3beta1, alpha4beta1, alpha5beta1, alpha6beta4, and ICAM-1 in endothelial cells; extracellular matrix proteins (ECMPs) and laminin alpha2 chain (merosin M chain) in basal membranes of vessels; and gene expression of vascular endothelial growth factor (VEGF), basic fibroblast growth factor (FGF2), and transforming growth factor beta1 (TGFbeta1), by in situ hybridization. Independently of tumour type and vascularity, laminin alpha2 chain expression was observed in the basal membranes of a limited proportion of vessels. In vitro experiments demonstrated laminin alpha2 chain expression mainly in early endothelial cell cultures, suggesting that laminin alpha2 chain expression in vivo can be considered a marker of early angiogenesis. Stromal and parenchymal vascularity was associated with laminin alpha2 chain expression in supraglottic carcinomas, whereas in the other tumours, laminin alpha2 chain-positive vessels were observed only in the stroma. In supraglottic carcinomas, VEGF-positive cells were mainly represented by neoplastic cells, whereas in the other tumours, the great majority of VEGF-positive cells were macrophages and fibroblasts. FGF2- and TGFbeta1-positive cells were macrophages and fibroblasts in all tumours. These observations suggest that in addition to the quantification and distribution of vessels, evaluation of their maturation may contribute to a better understanding of the role of angiogenesis in the growth and spread potential of solid tumours. In this regard, in supraglottic carcinomas, parenchymal angiogenesis seems to be regulated mainly by neoplastic cells, which may help to explain their high metastatic potential; in solid tumours of different histogenesis, different cells might be responsible for modulating tumour angiogenesis.

Interleukin-12 related cytokine gene expression at a tissue level in carcinomas of the larynx

Head and neck squamous cell carcinomas are highly immunogenic tumors in which tumor-infiltrating lymphocytes (TIL) consist largely of CD4, Th1, and Th2 lymphocytes and a minor proportion of other immune effector cells, such as macrophages and B cells. Interleukin (IL)-12 release and antigen presentation from macrophages induce Thl and Th2 differentiation. Gene expression for IL-12, interferon (IFN)gamma, IL-4, and other cytokines was studied by reverse transcriptase-polymerase chain reaction in tissue sections from laryngeal carcinomas to evaluate the mechanisms of Th1 and Th2 lymphocyte differentiation. Local effects of cytokines were probed evaluating immunohistochemically the presence of inducible nitric oxide synthase positive tumor-infiltrating macrophages in 13 cases of laryngeal carcinomas. IL-12 gene expression was observed in five cases and that for IFNgamma in nine cases. These cytokines were coexpressed in four specimens. IL-4 and transforming growth factor-beta1 were detected in 5 and 11 cases, respectively. These findings show that IL-12, IFNgamma, IL-4, and IL-6 in laryngeal carcinomas have different patterns of gene expression, suggesting distinct pathways of Th1 and Th2 lymphocyte differentiation to indicate that their exogenous modulation might be utilized in adoptive immunotherapy.

Interleukin-12-related cytokine gene expression in carcinomas of the breast, lung, and larynx: a study at tissue level

Tumor-infiltrating lymphocytes (TIL) consist of T helper 1 (Th1) and T helper 2 (Th2) cells producing interferon-gamma (IFN-gamma) and interleukin4 (IL-4), respectively. Interleukin-12 (IL-12) induces Th1 and Th2 differentiation. Therefore, IL-12, IFN-gamma, and IL-4 gene expression were evaluated by reverse transcriptase-polymerase chain reaction in carcinomas of the breast (n = 10), lung (n = 17), and larynx (n = 13) to investigate whether TIL activation is IL-12-related. IL-12 and IFN-gamma were codistributed in breast carcinomas, and IL-4 was demonstrated in three instances. IL-12 and IFN-gamma were detected in 15 and 13 lung carcinomas, respectively, and were codistributed in 11 cases; IL-4 was observed in 9 cases and was codistributed with IL-12 and IFN-gamma in 7 instances. IL-12 and IFN-gamma expression was observed in five and nine larynx carcinomas, respectively, and were codistributed in four cases; IL-4 was detected in five instances. These data indicate that breast, lung, and larynx carcinomas are characterized by different patterns of IL-12, IFN-gamma, and IL4 gene expression and suggest that Th1 activation may be induced, at least in part, by the neoplastic microenvironment.

Hodgkin/Reed-Sternberg cells and Hodgkin's disease in patients with B-cell chronic lymphocytic leukaemia: an immunohistological, molecular and clinical study of four cases suggesting a heterogeneous pathogenetic background

We report the immunohistological, molecular and clinical findings in four patients affected by B-cell chronic lymphocytic leukaemia (CLL) who developed "Richter's syndrome with Hodgkin's disease (HD) features" or "CLL with Hodgkin's transformation", all characterised by the presence of typical Hodgkin/Reed-Sternberg (H/RS) cells in lymph node biopsies. In three cases the nodal involvement by CLL was demonstrated both by the presence of a predominant background of CD5/CD19/CD23+ small lymphocytes and an IgH monoclonal rearrangement revealed by PCR analysis. Conversely, in the remaining case there was neither immunohistological nor molecular evidence of lymph node involvement by CLL. In all four cases H/RS cells were Epstein-Barr virus (EBV) latent membrane protein (LMP-1) positive. These findings suggest that the presence of H/RS cells in the first three patients, who had CLL/HD nodal involvement, might be related to transformation or clonal evolution of CLL cells in H/RS cells, which is in keeping with use of the term "CLL with Hodgkin's transformation". In the fourth case a de novo HD may be postulated, representing a second malignancy presumably not clonally related to CLL. In all cases a key pathogenetic role of EBV is suggested by the expression of LMP-1 in H/RS cells. Our findings indicate that the presence of typical H/RS cells in lymph node biopsies in CLL patients may reflect a heterogeneous pathogenetic background. The different clinico-pathologic settings should be taken into consideration because of their possible implications for patients' treatment and prognosis.

Regulation of TCL1 expression in B- and T-cell lymphomas and reactive lymphoid tissues

Chromosomal rearrangements observed in T-cell prolymphocytic leukemia involve the translocation of one T-cell receptor gene to either chromosome 14q32 or Xq28, deregulating the expression of cellular protooncogenes of unknown function, such as TCL1 or its homologue, MTCP1. In the human hematopoietic system, TCL1 expression is predominantly observed in developing B lymphocytes, whereas its overexpression in T cells causes mature T-cell proliferation in transgenic mice. In this study, using a newly generated monoclonal antibody against recombinant TCL1 protein, we extended our analysis mainly by immunohistochemistry and also by fluorescence-activated cell sorting and Western blot to a large tumor lymphoma data bank including 194 cases of lymphoproliferative disorders of B- and T-cell origin as well as reactive lymphoid tissues. The results obtained show that in reactive lymphoid tissues, TCL1 is strongly expressed by a subset of mantle zone B lymphocytes and is expressed to a lesser extent by follicle center cells and by scattered interfollicular small lymphocytes. In B-cell neoplasia, TCL1 was expressed in the majority of the cases, including lymphoblastic lymphoma, chronic lymphocytic leukemia, mantle cell lymphoma, follicular lymphoma, Burkitt lymphoma, diffuse large B-cell lymphoma (60%), and primary cutaneous B cell lymphoma (55%). TCL1 expression was observed in both the cytoplasmic and nuclear compartments, as confirmed by Western blot analysis. Conversely, TCL1 was not expressed in Hodgkin/Reed-Sternberg cells, multiple myelomas, marginal zone B-cell lymphomas, CD30+ anaplastic large cell lymphoma, lymphoblastic T-cell lymphoma, peripheral T-cell lymphoma, and mycosis fungoides. These data indicate that TCL1 is expressed in more differentiated B cells, under both reactive and neoplastic conditions, from antigen committed B cells and in germinal center B cells and is down-regulated in the latest stage of B-cell differentiation.

Cystic lymphoepithelial lesions of the parotid gland in HIV-1 infection

The benign cystic lymphoepithelial lesion (BLL) of the parotid gland is a rare disorder affecting HIV-1-infected patients. Here we describe the clinical and histopathological features of 10 cases of BLL, who presented to our observation between November 1992 and December 1996, before the combination antiretroviral therapy was introduced.

alpha5 integrin distribution and TGFbeta1 gene expression in supraglottic carcinoma: their role in neoplastic local invasion and metastasis

BACKGROUND

Head and neck carcinomas are characterized by tumor-infiltrating lymphocytes (TIL) producing cytokines. Adhesion molecules, extracellular matrix proteins (ECMPs), and cytokines regulate cell-cell and cell-ECMPs interactions. We investigated the distribution of these proteins to contribute to better understanding of their role in local tumor invasion and metastasis.

METHODS

Distribution of integrins, laminin, type IV collagen, tenascin, and fibronectin was immunohistochemically evaluated in 13 supraglottis carcinomas. Cytokines gene expression was assessed by reverse-transcriptase-polymerase chain reaction (RT-PCR).

RESULTS

Neoplastic cells were alpha2beta1, alpha3beta1, alpha4beta1, alpha5beta1 and alpha6beta1 positive. Normal and metaplastic epithelium was alpha5beta1 negative; the stroma of primary and metastatic tumors was tenascin and fibronectin positive. TGFbeta1 and IFNgamma gene expression was observed in the majority of tumors.

CONCLUSIONS

Because TGFbeta1 is known to down-modulate immune processes and to increase alpha2beta1, alpha5beta1, and tenascin distribution, we propose that their expression in neoplastic cells of supraglottis carcinoma might represent an immune-related process able to help tumor growth and progression.

The benign cystic lymphoepithelial lesion of the parotid gland is a viral reservoir in HIV type 1-infected patients

The presence of HIV-1 in cystic fluid aspirates from six cases of benign cystic lymphoepithelial lesion (BLL) of the parotid gland, a rare disorder affecting HIV-1-infected patients, has been investigated. HIV-1 p24 protein was present at a concentration ranging from 3 to 15 ng/ml, while it was undetectable in the peripheral blood of the same patients. The number of RNA copies of HIV-1 in the cystic fluids was high, ranging from 0.5 x 10(7) to 7.2 x 10(7) RNA copies/ml. BLL cystic fluid aspirates, despite the high level of HIV-1 RNA, were found to contain only a few infectious virions. The low infectivity correlated with the infrequent detection by electron microscopy of complete HIV-1 particles. The pathogenic mechanism leading to virus accumulation in the cystic fluid was studied by immunohistochemistry of tissue sections. p24 protein was associated with DRC-1+/S-100+ follicular dendritic reticulum cells, which were also present within the cystic cavities. Our findings are consistent with the possibility that the large amounts of virus present in the fluid derive from continuous shedding of HIV-1-infected cells from the surrounding lymphoid tissue.

"Composite" lymphoma, lymphoplasmacytoid and diffuse large B-cell lymphoma of the spleen: molecular-genetic evidence of a common clonal origin

We describe here the first well-characterized case of "composite" lymphoma of the spleen in which the two components were a low-grade and a high-grade B-cell non-Hodgkin's lymphomas. The patient was an elderly man with prominent splenomegaly and multiple hypoechogenic lesions of the spleen. A splenectomy was performed, and the macroscopic and histological findings showed the simultaneous presence of a "low-grade" B-cell lymphoma, lymphoplasmacytoid (immunocytoma) and a "high-grade" B-cell lymphoma (immunoblastic), which were spatially separated. The two lesions expressed the same immunoglobulin light chain (lambda), but the Southern blot analysis showed different patterns of immunoglobulin heavy chain (IgH) clonal rearrangement. PCR analysis followed by direct sequencing of the IgH-amplified rearrangement products provided molecular-genetic evidence that the two components of the composite lymphoma had the same clonal origin. Since both EBV LMP-1 and p53 were negative by immunohistochemistry, it is unlikely that EBV and p53 were involved in the neoplastic progression in this case. PCR analysis and direct sequencing of IgH-amplified rearrangement products are useful tools to investigate clonality in cases in which Southern blot analysis cannot be performed or does not provide conclusive findings.

Expression of p53 and retinoblastoma gene in high-grade nodal peripheral T-cell lymphomas: immunohistochemical and molecular findings suggesting different pathogenetic pathways and possible clinical implications

The expression of p53 and the retinoblastoma gene has been investigated by immunohistochemical and molecular analysis in 45 cases of nodal peripheral T-cell lymphoma with high-grade histology. Most cases (73.3 per cent) were primary nodal lymphomas without any extra-nodal site involvement. Most of them (75.6 per cent) were histologically classified as pleomorphic, small, medium, and large cell type. Immunohistochemistry detected p53 in nine cases (20 per cent). In each of these cases, the polymerase chain reaction (PCR)/heteroduplex analysis did not show the presence of mutations, this finding being consistent with an alteration of the p53 functional pathway, in the presence of a wild-type protein. The retinoblastoma gene product was detected by immunohistochemistry in 35 cases (77.8 per cent) and not detected in ten cases (22.2 per cent). In the latter cases, the reverse transcription (RT)-PCR analysis showed the presence of a specific retinoblastoma gene transcript in six cases and was negative in the remaining four cases. The immunohistochemical and molecular findings seem to be consistent with abnormalities of retinoblastoma gene expression at either the transcriptional or the post-transcriptional level. Since all nine p53-positive cases by immunohistochemical analysis were also retinoblastoma gene product-positive, and all ten retinoblastoma gene product-negative cases were also p53-negative, two different and mutually exclusive pathways of possible pathogenetic significance may be suggested, the former involving abnormalities of the functional pathway of p53 in the absence of mutations and the latter abnormalities of retinoblastoma gene expression at the transcriptional and/or post-transcriptional level. Finally, the clinico-pathological correlations showed that p53 immunohistochemical expression is significantly associated with a poorer response to intensive chemotherapy.

Testicular germ cells of HIV-seropositive asymptomatic men are infected by the virus

In situ PCR hybridization studies in the testis of infected asymptomatic subjects detected the presence of HIV-1 proviral DNA in the nuclei of germ cells at all stages of differentiation suggesting that HIV-seropositive men produce infected spermatozoa that are released in the genital tract. In all subjects studied spermatogenesis was normal, the presence of provirus was not associated with germ cell damage and a very mild local immune response was observed. The HIV hybridization pattern observed in germ cells supports the hypothesis of a clonal infection. It is suggested the possibility of a direct infection of the germ cells by cell-free virus and that the testis might represent a site of early viral localization, well tolerated because of the immune privilege of this organ.

Expression of Met protein and urokinase-type plasminogen activator receptor (uPA-R) in papillary carcinoma of the thyroid

Met protein encoded by MET oncogene is the high affinity receptor for hepatocyte growth factor (HGF)/scatter factor (SF). HGF/SF has to be cleaved in its heterodimeric form by the urokinase-type plasminogen activator (uPA) to become active as a ligand for Met receptor. The expression of Met protein and of the high affinity receptor for uPA (uPA-R) was investigated in 39 samples of papillary carcinoma using immunohistochemistry. Reactivity for Met protein was present in 33 of 34 tumours, mostly with a diffuse pattern of staining. Reactivity for uPA-R was present in 78 per cent of papillary tumours and exhibited a pattern of staining similar to that of Met protein. Staining for uPA-R was present in 23 of 25 cases (92 per cent) of papillary carcinoma with prominent sclerosis, and in only 1 of 7 cases (14 per cent) without sclerosis. Peritumoural normal thyroid, follicular adenomas, and follicular carcinomas were negative for Met protein and for uPA-R. Hyperfunctioning tall thyroid cells showed weak membrane reactivity for uPA-R and for Met protein. The findings of immunohistochemistry were confirmed at the mRNA level using in situ hybridization, since the signal for uPA-R and Met RNAs was detected in most tumour cells of five cases of papillary carcinoma.

The risk of acute leukemia in patients treated for Hodgkin's disease is significantly higher aft [see bined modality programs than after chemotherapy alone and is correlated with the extent of radiotherapy and type and duration of chemotherapy: a case-control study

BACKGROUND AND OBJECTIVE

Patients treated for Hodgkin's disease have an increased risk of developing subsequent acute leukemia. This co-operative study was conducted to assess the relative risk associated with several candidate factors including age, splenectomy, combined modality therapy and cumulative drug dose including alkylating agents and nitrosurea derivatives.

DESIGN AND METHODS

This study evaluated the risk of acute leukemia according to pretreatment variables and therapy modalities among 1659 patients treated for Hodgkin's disease and followed for a median time of 10 years. Both case-control and actuarial risk studies were performed. Median age was 34 years (range: 12-83); 53% of patients were splenectomized. As to the overall therapy, 348 patients (21%) were given radiotherapy (RT) alone, 375 (23%) chemotherapy (CT) alone (including MOPP, MOPP + ABVD or MOPP + ABVD + lomustine); 936 (56%) received both CT and RT, either as primary or salvage treatment.

RESULTS

The overall 15-year actuarial risk of leukemia was 4.2%; the hazard function curve showed two peaks of risk at the 3th and the 8th year from the initiation of therapy and no leukemia beyond the 12th year of follow-up. Risk of leukemia was 0.3% after RT alone, 2.8% after CT alone (2.2% after MOPP; 4.4% after MOPP + ABVD + lomustine), and 5.4% in patients given combined modality therapy (10.2% for RT + MOPP; 15.6% for RT + MOPP + lomustine). No leukemia occurred after ABVD alone and the risk was low (0.6%) when neither mechlorethamine nor lomustine were utilized. Patients who had received extended radiotherapy including abdomen and pelvis in addition to MOPP showed a significantly higher risk of leukemia compared to those given limited RT + MOPP (P = 0.01). Case-control analysis indicated advanced stage, type and duration (> 8 months) of CT and extension of RT as significant risk factors for leukemia. Compared to RT alone, the odds ratio was 5.9 after MOPP + extended RT, and 8 when a lomustine-containing regimen was used, as well. Neither age nor splenectomy were independent risk factors for leukemia; splenectomy was influential only when patients had been given MOPP chemotherapy, as well.

INTERPRETATIONS AND CONCLUSIONS

Both case-control and actuarial analyses indicated that: a) combined modality therapy with MOPP and extensive RT (including abdomen and pelvis), and the use of lomustine added to the leukemogenic risk of MOPP alone; b) programs without mechlorethamine, procarbazine and lomustine were almost devoid of leukemogenic risk.

Detection of infectious simian immunodeficiency virus in B- and T-cell lymphomas of experimentally infected macaques

An increasing frequency of malignant lymphomas occurs among patients infected by human immunodeficiency virus. Because of the close similarities to human malignancies, we used a nonhuman primate model to study the pathogenesis of simian immunodeficiency virus (SIV)-associated malignancies. Specifically, we investigated (1) the presence of the SIV genome in tumor cells, (2) the presence of coinfecting viruses, and (3) the presence of a rearrangement of the immunoglobulin and c-myc genes. We observed 5 cases of non-Hodgkin's lymphomas (4 of B- and 1 of T-cell origin) among 14 SIV-infected cynomolgus monkeys. No c-myc translocation was observed in the tumors, whereas B-cell lymphomas were characterized either by a monoclonal (in 2 of 4) or by an oligoclonal (in 2 of 4) VDJ rearrangements of the immunoglobulin heavy chain gene. Molecular, biological, and immunological analyses did show the presence of infectious SIV in the tumor cells of 1 T-cell and 2 oligoclonal B-cell lymphomas. Neither Simian T-lymphotropic nor Epstein-Barr viruses were detectable, whereas Simian herpes virus Macaca fascicularis-1 was detectable at a very low copy number in 3 of 4 B-cell lymphomas; however, only 1 of these also harbored the SIV genome. These results support the possibility that SIV may be directly involved in the process of B or T lymphomagenesis occurring in simian acquired immunodeficiency syndrome.

Presence and cellular distribution of HIV in the testes of seropositive subjects: an evaluation by in situ PCR hybridization

Cellular distribution of HIV-1 proviral DNA has been studied, by in situ PCR hybridization, in the testes of infected men who died at various stages of the disease. In seropositive asymptomatic subjects, HIV-1 proviral DNA was present in the nuclei of germ cells at all stages of their differentiation. The presence of provirus did not induce germ cell damage, was associated with normal spermatogenesis, and was not accompanied by morphologic signs of immune response. The observed HIV hybridization pattern of germ cells suggests clonal infection. Mechanisms responsible for HIV penetration in testicular germ cells remain to be clarified; however, the possibility of a direct infection of the germ cells by cell-free virus is suggested. In the testes of AIDS-deceased men, histologic features of hypoplasia with arrested spermatogenesis were evident, and few infected spermatogonia and spermatocytes were observed. The whole of these data demonstrates that the testis is a site of early viral localization that fails to elicit an immunological response, and that HIV-seropositive men produce infected spermatozoa that are released in the genital tract.

Pathogenetic and clinical implications of Bcl-6 and Bcl-2 gene configuration in nodal diffuse large B-cell lymphomas

Bcl-6 (LAZ-3) and Bcl-2 gene rearrangements have been respectively reported in 20-35 per cent and 10-25 per cent of diffuse large B-cell lymphomas (DLBCLs). Although these genetic lesions have been associated with different clinical outcomes (i.e., more favourable in Bcl-6 rearranged cases and poorer in Bcl-2 rearranged cases), their prognostic significance is still controversial. In the present study, we have investigated by Southern blot analysis the Bcl-6 and Bcl-2 gene configuration in a series of 80 lymph nodes involved by well-characterized DLBCLs, histologically defined according to the REAL and the updated Kiel classifications. The molecular findings have been correlated with the clinical features at presentation and with response to therapy. The majority of cases (57/80 = 71.2 per cent) had a centroblastic morphology. Bcl-6 rearrangements were detected in 23/80 cases (28.8 per cent), and were similarly associated with centroblastic (18/57 = 31.6 per cent) or immunoblastic (3/11 = 27.3 per cent) histotypes. In contrast, Bcl-2 was found to be rearranged in only three cases of centroblastic lymphoma (3.8 per cent). No significant differences were found between Bcl-6 rearranged and germline cases, as far as the clinical features at presentation are concerned. Forty-one patients, in whom the lymph node biopsy was performed at diagnosis, could be evaluated for response to treatment and clinical outcome. Most of these cases (30/41 = 73.2 per cent) were nodal DLBCL, without extranodal site involvement. Analysis of the clinical outcome showed no statistically significant differences between Bcl-6 rearranged and Bcl-6 germline cases (actuarial overall survival 50 per cent vs. 48 per cent, event-free survival 45 per cent vs. 46 per cent, at 4 years). These findings confirm that Bcl-6 rearrangements are the most frequent genetic lesion in DLBCL. The incidence of Bcl-2 involvement in our series is significantly lower than the figures reported in other studies, mainly from North American countries, probably reflecting heterogeneous patient selection and/or epidemiological variability. Finally, our results suggest that no relevant clinical differences are observed between Bcl-6 rearranged and Bcl-6 germline cases, when nodal DLBCLs are considered.

The patterns of IL2, IFN-gamma, IL4 and IL5 gene expression in Hodgkin's disease and reactive lymph nodes are similar

BACKGROUND AND OBJECTIVE

The lymph nodes involved in classic Hodgkin's disease (HD), i.e. mixed cellularity (MC) and nodular sclerosis (NS) subtypes, usually contain few (1-2%) Reed-Sternberg (RS) cells scattered in a background of lymphocytes, eosinophils, plasma cells and neutrophils. CD4+ T-lymphocytes are increased in number, express activation markers and cluster around RS cells. The presence of eosinophilia in most HD patients and the presence of hyper-IgE in a subset of them may suggest that activated lymph node T cells release large amounts of IL5 and IL4, respectively.

METHODS

The expression of four T-cell-associated cytokine genes, i.e. interleukin (IL)2, IL4, IL5 and interferon (IFN)-gamma, in frozen sections of 14 HD (7 MC, 7 NS) and 10 reactive lymph nodes was investigated by qualitative and quantitative reverse transcriptase-polymerase chain reaction (RT-PCR). T-cell clones were also raised from purified CD4+ lymphocytes of one HD lymph node and one reactive lymph node and tested for IL2, IL4, IL5 and IFN-gamma secretion in culture supernatants by immunoassays.

RESULTS

The transcripts of all the cytokine genes were detected in every lymph node irrespective of the HD or reactive nature. HD or reactive lymph node-derived CD4+ T-cell clones released the four cytokines according to a predominant T-helper (Th)0-type pattern. In more than half of the lymph nodes of either HD or reactive nature, there was a predominance of IL4 over IFN-gamma mRNA production (Th2-type pattern). In the remaining HD or reactive lymphadenopathies, either a balanced IL4/IFN-gamma mRNA ratio (Th0-type pattern) or a predominance of IFN-gamma over IL4 mRNA expression (Th1-type pattern) was observed.

INTERPRETATION AND CONCLUSIONS

The overall pattern of cytokine gene expression in classic HD is similar to that detected in reactive lymph nodes. Further studies are needed to determine whether differences in the absolute concentrations of cytokines released in HD versus reactive lymph nodes and the long-standing course of HD versus the self-limiting nature of reactive adenopathies may explain certain peculiar features of HD, such as eosinophilia, for example.

The pathobiography and death of Wolfgang Amadeus Mozart: from legend to reality

Mozart, perhaps one of the greatest geniuses of modern age, died mysteriously at the age of 35 in Vienna in 1791. The causes of his death are still somewhat obscure and debated since we do not have any documentation acceptable by current scientific standards. Inevitably, the conclusions reached are highly debatable. In the present article the various interpretations of Mozart's death are taken into consideration-from his possible poisoning to causes of death more acceptable by the present diagnostic criteria. We suggest that the terminal cause of death was brain hemorrhaging or stroke, complicated by broncopneumonia and associated with renal failure induced by proliferative glomerulonephritis and glomerulosclerosis.

Kaposi's sarcoma cells express the macrophage-associated antigen mannose receptor and develop in peripheral blood cultures of Kaposi's sarcoma patients

The mannose receptor (MR) is a surface 175-kd C-type lectin expressed by macrophages and dendritic cells. MR is involved in removal of effete cells, phagocytosis of mannose-coated particles, pinocytosis, and antigen presentation. Expression of MR was investigated in 17 biopsies of Kaposi's sarcoma (3 AIDS KS, 13 classical KS, and 1 transplant-associated KS) using three anti-MR monoclonal antibodies (3.29, D547, and PAM1). Immunostaining for MR was detected in 94 +/- 7% KS cells with spindle morphology. In normal tissues, MR was expressed by sinus-lining cells of spleen and lymph nodes, but it was not detected in endothelial cells lining normal hematic and lymphatic vessels, hemangioma, hemangioendothelioma, and lymphangioma. Expression of MR in KS cells prompted us to investigate the possibility that they derive from a circulating precursor cell. Peripheral blood mononuclear cells from 16 patients with KS (10 classical, 1 transplanted, and 5 AIDS) were cultured in PHA-conditioned medium for 10 to 14 days. Confluent monolayers of adherent spindle cells were detected in 8 of 11 classical KS, in 5 of 5 AIDS KS patients, and in 0 of 34 control patients. Peripheral-blood-derived KS-like cells were characterized by co-expression of macrophage and endothelial antigens being positive for CD45 (60%), CD68 (98%), MR (70%), CD14 (25%), VE-cadherin (70%), and von Willebrand factor (10%). When the immunophenotype of peripheral-blood-derived adherent cells was compared with that of KS spindle cells of tissue biopsies, it was found that both cell types are VE-cadherin+/MR+/CD68+, that peripheral-blood-derived spindle cells are CD34- and are less frequently stained for CD31 and von Willebrand factor, and that lesional KS cells do not express the leukocyte markers CD45 and CD18. Our findings are consistent with the possibility that KS lesions derive from tissue accumulation and local proliferation of a special subset of macrophages with endothelial features the normal counterpart of which are the sinus-lining cells of spleen and lymph nodes.

Meningeal localization in a patient with Hodgkin's disease. Description of a case and review of the literature

We report the case of a 21-year-old man in whom intracranial localization was discovered during initial staging at the onset of Hodgkin's disease (HD). The patient was treated by surgical excision, irradiation and chemotherapy and 50 months after completion of therapy is in remission with no evidence of HD. A brief review of the literature regarding 48 patients with intracranial Hodgkin's disease is presented.

Expression of Met protein in thyroid tumours

Met protein is a transmembrane 190 kD heterodimer with tyrosine kinase activity, encoded by c-MET oncogene. It serves as a high affinity receptor for hepatocyte growth factor (HGF)/scatter factor (SF), a cytokine which stimulates cell proliferation, motility, and invasion. Expression of Met protein was investigated in 116 thyroid tumours using an anti-Met mouse monoclonal antibody (DQ-13) active on paraffin-embedded material. Reactivity for DQ-13 was observed in 77 per cent of papillary carcinomas, in 70 per cent of Hürthle cell tumours, and rarely in other tumours. The staining was either uniformly present throughout the tumour or limited to nests of infiltrating tumour cells. In some Hürthle cell tumours, prominent accumulation of the protein was observed in the Golgi area. Reactivity for Met protein was decreased or absent in poorly differentiated tumours and was not influenced by tumour size, presence of lymph node metastases, or age of the patient. Immunostaining for Ki-67 revealed that cytoplasmic accumulation of Met protein was not associated with enhanced proliferation of tumour cells. Overexpression of Met protein in thyroid papillary carcinoma may result in increased motility of tumour cells, which in turn may account for intraglandular multifocal dissemination and early lymph node metastasis.

Expression of adhesion molecules and extracellular matrix proteins in glioblastomas: relation to angiogenesis and spread

We studied the immunohistochemical expression of inducible adhesion molecules, integrins and extracellular matrix proteins in 10 cases of glioblastoma multiforme in order to investigate their angiogenesis, local invasiveness, poor metastasizing properties and their lack of tumour infiltrating leukocytes. In glioblastomas endothelial proliferations represent the majority of vascular structures; they were positive for endothelial markers (vWF, CD31, VE-cadherin) and negative for macrophage markers (CD68, PAM-1). Immunohistologically, they were subtyped into: 1 solid-glomeruloid ICAM-1, alpha 2 beta 1, alpha 3 beta 1, alpha 5 beta 1 negative; 2 channelled-branching ICAM-1 negative and alpha 2 beta 1, alpha 3 beta 1, alpha 5 beta 1 positive; 3 channelled-telangiectatic ICAM-1, alpha 2 beta 1, alpha 3 beta 1, alpha 5 beta 1 positive. In channelled proliferations, the expression and distribution of tenascin and merosin in the basal membrane was similar to that of normal brain vessels. The expression of all these molecules might indicate different steps of maturation of endothelial proliferations. The majority of endothelial proliferations may be immunohistologically considered as incomplete vascular structures; this might account for the low metastasizing tendency and low recruitment of leukocytes by these tumours. Neoplastic astrocytes were GFAP-1, ICAM-1, VCAM-1, alpha 2 beta 1, alpha 3 beta 1 and alpha 5 beta 1 immunoreactive and alpha 6 beta 4 negative: this allows them to interact with extracellular matrix proteins and might, in part, explain the tendency of glioblastomas to infiltrate locally.

Monoclonal antibodies PG-B6a and PG-B6p recognize, respectively, a highly conserved and a formol-resistant epitope on the human BCL-6 protein amino-terminal region

The human BCL-6 gene, which is rearranged in approximately 30% of diffuse large B cell lymphomas, encodes a 706-amino-acid nuclear protein of the Kruppel-type zinc finger transcription factors mainly expressed in normal germinal center B cells and related lymphomas. Four monoclonal antibodies (PG-B6, PG-B6a, PG-B6p, and PG-B6m), specifically directed against the human BCL-6 protein, were generated by immunizing BALB/c mice with a recombinant protein corresponding to the BCL-6 amino-terminal region (amino acids 3 to 484). The PG-B6 monoclonal antibody reacted with a BCL-6 epitope sensitive to fixatives and preserved in all mammalian species. PG-B6a (a is for avian) recognized the most evolutionarily conserved BCL-6 epitope (expressed in all animal species including avian). PG-B6p (p is for paraffin) recognized a fixative-resistant epitope of BCL-6 that was detectable on paraffin sections after microwave heating in 1 mmol/L EDTA buffer. PG-B6m (m is for mantle) was the least specific monoclonal antibody as, in addition to BCL-6, it reacted with a yet undefined antigen selectively located in the cytoplasm of mantle and marginal zone B cells. All monoclonal antibodies detected strong nuclear expression of BCL-6 in follicular lymphomas, diffuse large B cell lymphomas, Burkitt's lymphomas, and nodular, lymphocyte-predominance Hodgkin's disease. In diffuse large B cell lymphomas, BCL-6 expression was independent of BCL-6 gene rearrangements and did not correlate with expression of other markers or the proliferation index. BCL-6 was not expressed in B-CLL, hairy cell leukemia, mantle-cell- and marginal-zone-derived lymphomas. Labeling of paraffin sections with PG-B6p proved useful for differentiating proliferation centers in B-CLL (BCl-2+/BCL-6-) from trapped germinal centers in mantle cell lymphomas (BCL-2-/BCL-6+) and for identifying neoplastic cells in cases of nodular, lymphocyte-predominance Hodgkin's disease. Because of their high specificity, wide reactivity in humans and animal species including avians (PG-B6a), and suitability for labeling routine paraffin sections (PG-B6p), the reagents described in this paper should prove valuable in both research and diagnostics.

Recurrent thymoma: evidence for histological progression

The clinicopathological features of nine cases of recurrent thymomas have been studied. At presentation, all cases were histologically classified as thymomas with cortical differentiation, including predominantly cortical thymoma, cortical thymoma and well-differentiated thymic carcinoma. In five cases the morphological features of the recurrence(s) were suggestive of a histological progression of the tumour from predominantly cortical thymoma to cortical thymoma and/or well-differentiated thymic carcinoma, usually associated with a more advanced clinical stage, the latter indicating a clinical progression. These findings suggest that all types of thymoma with cortical differentiation are histologically and histogenetically related neoplasms, associated with a more aggressive clinical behaviour and a significant risk of recurrence. The overall outcome of patients with recurrent thymoma in this series was poor, since six patients (66.6%) died due to the disease, 2-14 years after the first diagnosis. The clinical implication of our findings is that thymomas with cortical differentiation always need careful follow-up, even in those cases which are not obviously invasive at onset.

Analysis of the BCL-6 gene configuration in diffuse B-cell non-Hodgkin's lymphomas and Hodgkin's disease

BCL-6 is a novel proto-oncogene that codes for a zinc-finger protein sharing homologies with many transcription factors. It has recently been shown that BCL-6 is involved in chromosome band 3q27 aberrations in non-Hodgkin's lymphomas (NHLs) and BCL-6 rearrangements have been detected in 34-45 per cent of diffuse large cell lymphomas with B immunophenotype. We have studied the BCL-6 gene configuration by Southern blot analysis in 60 cases of B-cell NHL and in 17 cases of Hodgkin's disease (HD). BCL-6 was rearranged in 15/46 (32.6 per cent) diffuse B-large cell lymphomas, mainly with centroblastic morphology, and in 2/11 (18.2 per cent) follicular (centroblastic-centrocytic) lymphomas. Conversely, all cases of HD, including four cases of lymphocyte predominant, nodular type (nodular paragranuloma), had a germline configuration. These findings confirm that BCL-6 is rearranged in a significant percentage of diffuse B-large cell lymphomas, suggesting that this proto-oncogene might have a pathogenetic role in this subset of NHLs, but our preliminary analysis suggests that BCL-6 lesions are not involved in the pathogenesis of HD. However, further investigations using more sensitive techniques are required to confirm these findings.

The lymphoepithelial organization of the tonsil: an immunohistochemical study in chronic recurrent tonsillitis

Interactions between leukocytes and crypt epithelium were extensively investigated in 12 cases of chronic recurrent tonsillitis, using immunohistochemistry and cytofluorimetric analysis of cell suspensions. Intraepithelial leukocytes are a mixed cell population composed of 50 per cent CD20-positive B lymphocytes, 40 per cent T lymphocytes with a 2.7 CD4/CD8 ratio, and 10 per cent CD68-positive macrophages. About 4 per cent of intraepithelial leukocytes are proliferating cells, as indicated by Ki-67 staining. Leukocyte infiltration is associated with expression on epithelial cells of the adhesion molecules ICAM-1 and VCAM-1. Crypt epithelium is supported by a basement membrane showing frequent interruptions and connected with the reticular stroma of the lymphoid tissue, which was stained for fibronectin, tenascin, collagen, and laminin. Extracellular matrix (ECM) distribution was correlated with integrin expression on B and T lymphocytes. It was found that the ECM was arranged differently in the follicles and in the extrafollicular area and that B and T lymphocytes exhibited different patterns of integrin expression.

Recombinant interferon-alpha and ursodeoxycholic acid versus interferon-alpha alone in the treatment of chronic hepatitis C: a randomized clinical trial with long-term follow-up

OBJECTIVES

The purpose of this study was to compare, within a randomized controlled trial, the efficacy of recombinant interferon-alpha in combination with ursodeoxycholic acid versus interferon-alpha alone in the treatment of chronic HCV hepatitis.

METHODS

Forty anti-HCV positive chronic hepatitis patients with ALT levels persistently greater than 3 times the upper normal level were randomized to receive either interferon-alpha (6 million units three times/wk for 6 months) plus ursodeoxycholic acid (10 mg/kg/day for 9 months) (n = 20) or interferon-alpha (6 million units three times/wk for 6 months) alone (n = 20). Disease activity was monitored monthly by ALT measurement until 18 months after interferon-alpha cessation. Serum HCV-RNA was measured at baseline and after 6, 9, and 24 months. Liver biopsies (basal and at the 9th month) were evaluated blindly and scored by Knodell's criteria.

RESULTS

The probability of full or partial response during interferon-alpha treatment was similar in the two groups. The probability of biochemical relapse (i.e, any persistent return of ALT above normal) after 18-month of posttreatment follow-up was 75% in both the combination and the monotherapy group. Relapse, however, occurred significantly later in the combination than in the monotherapy group (6.6 +/- 5.4 [SD] months and 1.8 +/- 1.6 months after IFN-alpha cessation, respectively, p < 0.02). Severe biochemical relapse (i.e., a persistent ALT elevation greater than 3 times normal) occurred more frequently and earlier (p = 0.05) in patients treated with interferon-alpha (58.3%) than in those receiving the combination therapy (27.3%). The cumulative duration of normalized ALT periods during and after treatment was significantly greater (p = 0.005, chi 2) in patients treated with IFN-alpha + UDCA than with monotherapy (189/354 months vs 136/323 months. Lobular necrosis improved in both groups (p = 0.056 and p = 0.001, respectively), whereas portal inflammation improved (p = 0.009) only in the combination therapy group. Among the 30 patients who were viremic at entry, plasma HCV-RNA was no longer detectable after 6 months in four from the combination group and in five from the monotherapy group, yet all patients but one returned HCV-RNA positive 3 months after interferon-alpha cessation and were still viremic after 18 months. Cox's multiple regression identified the histological degree of posttreatment portal inflammation as the sole positive indicator of relapse.

CONCLUSIONS

The combination of interferon-alpha and ursodeoxycholic acid prolongs the efficacy of interferon-alpha alone in chronic hepatitic C by delaying the probability of biochemical relapse and/or by reducing its severity, without affecting HCV viremia.

Adhesion molecules and lymphocyte recruitment in lymphocytic thyroiditis, thyroid papillary carcinoma and parotid adenolymphoma

Lymphocytic infiltrates are usually present in chronic lymphocytic thyroiditis, thyroid papillary carcinoma and parotid adenolymphoma. We selected these conditions to investigate the mechanisms of recruitment and organization of lymphocytic infiltrates in extranodal tissues. MoAbs in immunoperoxidase were used to identify the expression of ICAM-1 and VCAM-1 on endothelial cells (EC), and of their ligands LFA-1 and VLA-4 on lymphocytes and accessory cells. VCAM-1 positive EC were rarely observed in thyroids devoid of lymphocyte infiltration. Conversely, EC in chronic lymphocytic thyroiditis and in papillary carcinoma showed positive immunostaining for VCAM-1 and ICAM-1. These findings were associated with the presence of lymphocytes positive for the ligands VLA-4 and LFA-1. The upregulated expression of VCAM-1 on perifollicular capillaries was co-distributed with an accumulation of VLA-4 positive lymphocytes. In adenolymphoma, all EC were ICAM-1 positive, whereas the majority of vessels were VCAM-1 negative. Consequently the majority of lymphoid cells were LFA-1 positive and VLA-4 negative. We suggest that ICAM-1 and VCAM-1 expression on EC play a role in the recruitment of lymphocyte infiltration in chronic lymphocytic thyroiditis and papillary carcinoma. Furthermore, the upregulation of VCAM-1 and VLA-4 in thyroid reactive and neoplastic conditions may be linked to an immune response possibly related to thyroid tissue antigens.

[Gastrointestinal lymphomas]

Non-Hodgkin lymphomas affecting extranodal tissues can be primitive or secondary. The area most frequently involved is the gastrointestinal tract. MALT-type lymphomas are B-cell lymphomas characterized by small cells originating from the lymphoid tissue of the mucosa. The criteria for a correct diagnosis of extranodal lymphomas are morphological, but include immunophenotypic and immunogenotypic analysis. Gastrointestinal lymphomas consist of B-cell and T-cell lymphomas. B cell-lymphomas include: small cell B-lymphomas, large cell B-lymphomas, immunoproliferative small intestinal disease; multiple lymphomatous polyposis, follicular lymphomas, B-cell lymphomas centrocytic type. T-cell lymphomas include enteropathy-associated and non enteropathy-associated lymphomas.

Expression of intercellular adhesion molecule-1 and vascular cell adhesion molecule-1 in undifferentiated nasopharyngeal carcinoma (lymphoepithelioma) and in malignant epithelial tumors

Immunoreactivity for intercellular adhesion molecule-1 (ICAM-1) and for vascular cell adhesion molecule-1 (VCAM-1), two adhesion molecules of the immunoglobulin (Ig) superfamily, was tested and measured on tissue sections from 16 undifferentiated nasopharyngeal carcinomas (U-NPC), 12 keratinizing squamous cell carcinomas (SCCs) of the head and neck region, and 54 malignant epithelial tumors of various origin. Neoplastic cells of all cases of U-NPC were diffusely and intensely stained for ICAM-1 and VCAM-1. Moreover, ICAM-1 messenger RNA (mRNA) and VCAM-1 mRNA were detected by Northern blot analysis of RNA extracts from two tumors. In the other epithelial tumors focal or diffuse staining for ICAM-1 was observed in 40 cases (66%), whereas reactivity for VCAM-1 was detected in a single case of metastatic undifferentiated carcinoma of unknown origin. The biopsy specimens of U-NPC showed variable infiltration by leukocytes, which were positive for the integrins lymphocyte function antigen-1 (LFA-1) and alpha-4/beta-1, the corresponding ligands for ICAM-1 and VCAM-1. The possibility that ICAM-1 and VCAM-1 on neoplastic cells may favor the intratumoral recruitment of leukocytes in a way similar to that occurring in crypt epithelium of the palatine tonsil is discussed.

Cytokine production and expression of adhesion molecules and integrins in tumor infiltrating lymphomononuclear cells of non-small cell carcinomas of the lung

Localization of intercellular adhesion molecule-1 and vascular cell adhesion molecule-1, and of their ligands, lymphocyte function-associated antigen-1 and very late activation antigen-4, was determined in non-small cell lung carcinomas and tumor-free lung. Messenger RNA expression for interleukins (IL) IL-1 beta, IL-2, IL-4, IL-5, IL-6, IL-10, tumor necrosis factor-alpha, transforming growth factor-beta, interferon-gamma, granulocyte-macrophages colony stimulating factor, and human perforin-1 was assessed by in situ hybridization on the same tissues. Intercellular adhesion molecule-1 was expressed in all blood vessels, whereas only a low number of vessels displayed vascular cell adhesion molecule-1 immunoreactivity. Tumor infiltrating lymphomononuclear cells consisted of lymphocyte function-associated antigen-1-positive cells and of a lower number of very late activation antigen-4-positive cells. All squamous cell carcinomas consisted of intercellular adhesion molecule-1-positive neoplastic cells infiltrated by lymphocyte function-associated antigen-1-positive tumor infiltrating lymphomononuclear and CD-la-positive Langerhans cells, whereas only a minor number of adenocarcinomas displayed a consistent number of intercellular adhesion molecule-1-positive neoplastic cells. Tumor infiltrating lymphomononuclear cells showed a wider production of cytokines when compared to bronchus-associated lymphoid tissue of tumor-free lung. Moreover, cells producing interferon-gamma, IL-4, and IL-5 were more numerous in squamous cell carcinomas than in adenocarcinomas. These findings indicate that the lung squamous cell carcinoma might represent a neoplastic microenvironment able to induce activation of tumor infiltrating lymphomononuclear cells more efficiently than the adenocarcinoma.

Prognostic value of bone marrow histology in chronic lymphocytic leukemia. A study of 335 untreated cases from a single institution

BACKGROUND AND METHODS

A significant correlation between bone marrow (BM) histology, survival and disease progression (DP) probability has been observed by several authors in chronic lymphocytic leukemia (CLL). The prognostic value of BM histologic patterns on survival and disease progression probability was investigated in 335 B-CLL patients.

RESULTS

Actuarial survival probability estimated by univariate analysis proved to be significantly influenced by stage (p < 0.0001), BM histology (p = 0.01), and by the following parameters: anemia (p = 0.0005), splenomegaly (p < 0.001), CLL-related symptoms (p < 0.01), thrombocytopenia (p < 0.01), number of involved nodal areas (p = 0.01) and peripheral lymphocyte count over 30 x 10(9)/L (p < 0.05). In this series we did not detect a discriminating prognostic effect for BM histology within the individual stages. Cox multivariate regression analysis failed to demonstrate a significant value for BM histology, while stage and anemia emerged as the best prognostic variables. Actuarial DP free probability in 294 untreated patients with A and B stages was significantly related to stage (p < 0.00001) and to BM pattern (p = 0.01).

CONCLUSIONS

Despite the clear correlation between the D pattern of BM involvement and advanced and early progressive disease, we were unable to demonstrate an independent prognostic value for BM histology. These findings suggest that stage emerged as the best predictive factor of survival probability in our B-CLL patients.

Co-expression of endothelial cell and macrophage antigens in Kaposi's sarcoma cells

The histopathogenesis of Kaposi's sarcoma (KS) was investigated using immunocytochemistry in 12 skin biopsies obtained from two AIDS patients, nine patients with the classic form, and one organ-transplant patient. KS cells revealed a peculiar antigenic profile, being characterized by co-expression of endothelial and macrophage markers. KS cells were stained for von Willebrand factor (vWF); for vascular endothelial (VE) cadherin, an endothelial specific adhesion molecule; and for PECAM/CD31. In addition, they expressed the macrophage antigens PAM-1, CD68, and CD14, and were positive for vitronectin receptor and alpha-1,5,6/beta-1 integrins. KS cells were weakly stained for ICAM-1 in 6 of 12 cases and were negative for VCAM-1 and E-selectin.