Dissection of DLBCL microenvironment provides a gene expression-based predictor of survival applicable to formalin-fixed paraffin-embedded tissue.

Background: Gene expression profiling (GEP) studies recognized a prognostic role for tumor microenvironment (TME) in diffuse large B-cell lymphoma (DLBCL), but the routinely adoption of prognostic stromal signatures remains limited. Patients and methods: Here, we applied the computational method CIBERSORT to generate a 1028-gene matrix incorporating signatures of 17 immune and stromal cytotypes. Then, we carried out a deconvolution on publicly available GEP data of 482 untreated DLBCLs to reveal associations between clinical outcomes and proportions of putative tumor-infiltrating cell types. Forty-five genes related to peculiar prognostic cytotypes were selected and their expression digitally quantified by NanoString technology on a validation set of 175 formalin-fixed, paraffin-embedded DLBCLs from two randomized trials. Data from an unsupervised clustering analysis were used to build a model of clustering assignment, whose prognostic value was also assessed on an independent cohort of 40 cases. All tissue samples consisted of pretreatment biopsies of advanced-stage DLBCLs treated by comparable R-CHOP/R-CHOP-like regimens. Results: In silico analysis demonstrated that higher proportion of myofibroblasts (MFs), dendritic cells, and CD4+ T cells correlated with better outcomes and the expression of genes in our panel is associated with a risk of overall and progression-free survival. In a multivariate Cox model, the microenvironment genes retained high prognostic performance independently of the cell-of-origin (COO), and integration of the two prognosticators (COO + TME) improved survival prediction in both validation set and independent cohort. Moreover, the major contribution of MF-related genes to the panel and Gene Set Enrichment Analysis suggested a strong influence of extracellular matrix determinants in DLBCL biology. Conclusions: Our study identified new prognostic categories of DLBCL, providing an easy-to-apply gene panel that powerfully predicts patients' survival. Moreover, owing to its relationship with specific stromal and immune components, the panel may acquire a predictive relevance in clinical trials exploring new drugs with known impact on TME.

Pelvic myeloid sarcoma: a multidisciplinary approach.

Myeloid sarcoma (MS) is a rare tumor mass derived from the extramedullary proliferation of blasts of one or more of myeloid lineages. It usually occurs at an anatomical site other than the bone marrow (BM). Among the anatomical site which may be involved, female genital tract is a rare localization. When MS follows a previous history of myeloid pathology it is usually associated to a poor prognosis. To date this disease was managed with exploratory laparotomy or with surgical debulking. The authors report a case of laparosc6pic diagnosis of a pelvic myeloid sarcoma in a patient previously affected by acute mycloid leukemia, evidencing the importance of minimally invasive diagnosis and subsequent multidisciplinary management.

Unilesional folliculotropic mycosis fungoides: a true rarity in the clinico-pathologic spectrum?

AIM: Unilesional mycosis fungoides (UMF) was firstly described in 1981 as solitary lesion with clinical and histological features of MF. Although over 100 cases have been reported in the literature, there is a lack of clear-cut criteria characterising UMF. Only 10 cases featured by follicolotropism of the neoplastic T-cells have been reported: the so-called unilesional folliculotropic MF (UFMF). This paper questions whether or not UFMF should be considered as a true rarity in MF clinico-pathological spectrum. METHODS: We retrieved 28 folliculotropic MF cases in the database of the Dermatological Divisions of Bologna (12 patients) and Florence University (16 patients). Four of them were UFMF patients (2 males and 2 females, mean age 45 years; median age: 39 years). RESULTS: All patients achieved after therapy disease complete remission. Notably, only one patient was treated with radiotherapy, that seems the most recommended strategy in UMF. For the remaining patients, we choose different managements in order to achieve both clinical efficacy and the best aesthetical outcome. CONCLUSION: No definitive conclusions can be drawn whether or not UFMF has the same indolent clinical course of UMF. Recently, Kempf et al. reported 2 UFMF patients with progression to tumour stage and large-cell transformation, respectively. UFMF in our database is 14.3% of the 28 FMF cases. Our data suggest that UFMF can be regarded as a true rarity in MF clinico-pathological spectrum.

Blastic plasmacytoid dendritic cell neoplasm (BPDCN): the cutaneous sanctuary.

AIM: Blastic plasmacytoid dendritic cell neoplasm (BPDNC) is a rare tumour, which stems from plasmacytoid dendritic cells. Although the aetiology is still unclear, in the last few years various reports suggested a potential role of chromosomal aberrations in the oncogenesis. The disease is currently enclosed among "acute myeloid leukemia (AML) and related precursor neoplasms" in the last WHO classification. BPDCN has an aggressive course, however, it has been suggested that an exclusive cutaneous involvement at presentation is related to a better clinical outcome. METHODS: We review the literature about BPDCN, and we present a series of 11 cases, all characterised by disease limited to the skin at presentation. Furthermore, we examined all cases of the last 10 years stored in the database of the multidisciplinary study group on cutaneous lymphomas of the University of Florence. RESULTS: Basing on the clinical features, patient were classified into two groups: with a single-lesion or multiple eruptive-lesions presentation. The former were treated with radiotherapy (limited field, electron beam therapy). The latter were treated with different therapeutic options, depending on age and co-morbidities. All patients with a single lesion achieved complete response. Five of 6 patients with eruptive lesions achieved a clinical response (2 complete and 3 partial response). Notably, the progression free survival was higher in the single-lesion than in the eruptive-lesion group (23 vs. 9 months). However all patients relapsed and 8 of 11 died. CONCLUSION: Although the small number of selected patients, we could speculate that the concept of "cutaneous sanctuary" is particularly true in patients with a single lesion-presentation. In these patients, especially if >70 year-old aged, radiotherapy should be encouraged as the treatment of choice.

A20 deletion is associated with copy number gain at the TNFA/B/C locus and occurs preferentially in translocation-negative MALT lymphoma of the ocular adnexa and salivary glands.

The genetic basis of MALT lymphoma is largely unknown. Characteristic chromosomal translocations are frequently associated with gastric and pulmonary cases, but are rare at other sites. We compared the genetic profiles of 33 ocular adnexal and 25 pulmonary MALT lymphomas by 1 Mb array-comparative genomic hybridization (CGH) and revealed recurrent 6q23 losses and 6p21.2-6p22.1 gains exclusive to ocular cases. High-resolution chromosome 6 tile-path array-CGH identified NF-kappaB inhibitor A20 as the target of 6q23.3 deletion and TNFA/B/C locus as a putative target of 6p21.2-22.1 gain. Interphase fluorescence in situ hybridization showed that A20 deletion occurred in MALT lymphoma of the ocular adnexa (8/42=19%), salivary gland (2/24=8%), thyroid (1/9=11%) and liver (1/2), but not in the lung (26), stomach (45) and skin (13). Homozygous deletion was observed in three cases. A20 deletion and TNFA/B/C gain were significantly associated (p<0.001) and exclusively found in cases without characteristic translocation. In ocular cases, A20 deletion was associated with concurrent involvement of different adnexal tissues or extraocular sites at diagnosis (p=0.007), a higher proportion of relapse (67% versus 37%) and a shorter relapse-free survival (p=0.033). A20 deletion and gain at TNFA/B/C locus may thus play an important role in the development of translocation-negative MALT lymphoma.

Myeloid sarcoma: clinico-pathologic, phenotypic and cytogenetic analysis of 92 adult patients.

Myeloid sarcoma (MS) is a rare neoplasm whose knowledge is largely based on case reports and/or technically dated contributions. Ninety-two MSs in adulthood with clinical data available were evaluated both morphologically and immunohistochemically. Seventy-four cases were also studied by fluorescent in situ hybridization on tissue sections and/or conventional karyotyping on bone marrow or peripheral blood. Histologically, 50% of the tumors were of the blastic type, 43.5% either monoblastic or myelomonocytic and 6.5% corresponded to different histotypes. CD68/KP1 was the most commonly expressed marker (100%), followed by myeloperoxidase (83.6%), CD117 (80.4%), CD99 (54.3%), CD68/PG-M1 (51%), CD34 (43.4%), terminal-deoxy-nucleotidyl-transferase (31.5%), CD56 (13%), CD61/linker for activation of T cells (2.2%), CD30 (2.2%) and CD4 (1.1%). Foci of plasmacytoid monocyte differentiation were observed in intestinal cases carrying inv16. Chromosomal aberrations were detected in about 54% of cases: monosomy 7(10.8%), trisomy 8(10.4%) and mixed lineage leukemia-splitting (8.5%) were the commonest abnormalities, whereas t(8;21) was rare (2.2%). The behavior was dramatic irrespective of presentation, age, sex, phenotype and cytogenetics. Most if not all, long survivors received bone-marrow transplantation. The present report expands the spectrum of our knowledge showing that MS has frequent monoblastic/myelomonocytic differentiation, displays distinctive phenotypic profile, carries chromosomal aberrations other than t(8;21), and requires supra-maximal therapy.

Hodgkin-like lymphoma, simulating anaplastic large cell lymphoma in the patient after renal transplantation--unusual case report and literature review.

UNLABELLED: We report the atypical case of posttransplant lymphoproliferative disorder (PTLD) diagnosed in 55-year men 9 years after renal transplantation. It was evaluated only by bone marrow biopsy, which showed its total involvement with malignant lymphoma. It was composed of two populations of lymphoid cells: large RS-like cells and small to medium ones, with slightly angular nuclei without visible nucleoli. Both cellpopulations did not show positive reaction for typical B cell markers (CD20, CD79a). Large RS-like cells were positive with CD30 and EBV-LMP. However, negative reaction with CD15 and positive reactions with UCHL1 and EMA were not consistent with classical type of Hodgkin lymphoma. Morphological picture and immunophenotype had suggested anaplastic T cell lymphoma. Because of negative reaction with ALK1, initial diagnosis was ALCL ALK-negative. Then, additional stains with BOB1 and Oct2 were performed, which were positive. Taking it into account the diagnosis was changed; finally Hodgkin-like B lymphoma was diagnosed. The patient was treated with CHOP regimen with good response. 5 years after primary diagnose of PTLD he is steel free of disease. CONCLUSIONS: 1. Apart from typical forms of PTLD, one may expect cases with nonspecific morphological picture and phenotype. 2. Negative reactions with typical immunohistochemical markers for lymphocytes of B cell line do not exclude the possibility of B-cell proliferation.

Extrahepatic manifestations of Hepatitis C Virus infection: a general overview and guidelines for a clinical approach.

Hepatitis C Virus is associated with a wide series of extrahepatic manifestations. Based on available data the link between the virus and some of these extrahepatic diseases is only suggested and needs further confirmation. Hepatitis C Virus-related lymphoproliferative disorders, whose prototype is mixed cryoglobulinaemia, represent the most closely related extrahepatic manifestations of Hepatitis C Virus. Other Hepatitis C Virus-associated disorders include nephropathies, thyreopathies, sicca syndrome, idiopathic pulmonary fibrosis, porphyria cutanea tarda, lichen planus, diabetes, chronic polyarthritis, cardiopathy and atherosclerosis. A pathogenetic link between Hepatitis C Virus and some extrahepatic manifestations was confirmed by their responsiveness to antiviral therapy, which is now deemed the first therapeutic option to consider. By contrast, there are diseases where treatment with interferon was ineffective or dangerous. The aim of the present paper is to outline the most recent evidence concerning extrahepatic disorders that are possibly associated with Hepatitis C Virus infection. Special emphasis will be given to discussion of the most appropriate clinical approaches to be adopted in order to diagnose, treat (possibly prevent) and follow-up extrahepathic diseases in patients with Hepatitis C Virus infection.

Understanding CD30 biology and therapeutic targeting: a historical perspective providing insight into future directions.

CD30 is a member of the tumor necrosis factor receptor superfamily. It is characteristically expressed in certain hematopoietic malignancies, including anaplastic large cell lymphoma and Hodgkin lymphoma, among others. The variable expression of CD30 on both normal and malignant lymphoid cells has focused research efforts on understanding the pathogenesis of CD30 upregulation, its contribution to lymphomagenesis through anti-apoptotic mechanisms, and its effect on cell survival. Given the restriction of CD30 to certain tumor types, the logical extension of this has been to attempt to exploit it as a therapeutic target. The efficacy of naked anti-CD30 antibodies in practice was, however, modest. Moreover, combinations with bacterial toxins and radioimmunoconjugates have also had limited success. The development of the antibody-drug compound brentuximab vedotin (BV), however, has rejuvenated interest in CD30 as a tumor target. Phase I and II clinical trials in Hodgkin lymphoma, peripheral T-cell lymphoma, cutaneous T cell lymphoma, and even CD30-expressing B-cell lymphomas, have shown the compound is well tolerated, but more importantly, able to deliver meaningful disease control even in patients with multiply relapsed or refractory disease. FDA approval has been granted for its use in relapsed Hodgkin lymphoma and systemic anaplastic large cell lymphoma. A recent phase III trial of BV in cutaneous T-cell lymphoma has confirmed its superiority to standard of care therapies. In this manuscript, we explore the history of CD30 as a tumor marker and as a therapeutic target, both in the laboratory and in the clinic, with a view to understanding future avenues for further study.

Expression pattern of intracellular leukocyte-associated proteins in primary mediastinal B cell lymphoma.

Two microarray studies of mediastinal B cell lymphoma have shown that this disease has a distinct gene expression profile, and also that this is closest to the pattern seen in classical Hodgkin's disease. We reported previously an immunohistologic study in which the loss of intracellular B cell-associated signaling molecules in Reed-Sternberg cells was demonstrated, and in this study we have investigated the expression of the same components in more than 60 mediastinal B cell lymphomas. We report that these signaling molecules are frequently present, and in particular that Syk, BLNK and PLC-gamma2 (absent from Reed-Sternberg cells) are present in the majority of mediastinal B cell lymphomas. The overall pattern of B cell signaling molecules in this disease is therefore closer to that of diffuse large B cell lymphoma than to Hodgkin's disease, and is consistent with a common cell of origin as an explanation of the similar gene expression profiles.

Posttransplant lymphoproliferative disorder: morphological picture and diagnostic difficulties.

Posttransplant lymphoproliferative disorder (PTLD) is a well-known complication of both solid organ and bone marrow transplantation. It includes a wide spectrum of proliferative changes ranging from reactive hyperplasia, borderline lesions to malignant lymphomas. PTLD develops in 1% to 10% of transplant recipients. We present 10 cases of PTLD. Five developed after renal, four after liver, and one after heart transplantation. Among the early lesions, we diagnosed two reactive plasmacytic hyperplasias; one infectious mononucleosis-like PTLD; one polymorphic lesion; and one "mixed" case of plasmacytic hyperplasia in one tonsil with a polymorphic PTLD in the second one. Among the lymphomas, we observed three diffuse large B-cell lymphoma (DLBCL); one mantle lymphoma; and one Hodgkin lymphoma-like PTLD. The morphological pictures of six PTLD cases were typical and posed no diagnostic problems. In the one case of plasmacytic hyperplasia, the lymph node morphology was atypical with atrophy of lymphoid components accompanying plasma cell proliferation. Contrary to a good prognosis of early, reactive PTLD, this patient experienced a rapid course and succumbed to sepsis. The most difficult case was a rare Hodgkin lymphoma-like PTLD, which was diagnosed only by a bone marrow biopsy. Because of its noncharacteristic immunophenotype, it was primarily diagnosed as an anaplastic lymphoma of the T-cell type. After additional immunohistochemical studies (BOB and OCT2), we established the final diagnosis of Hodgkin lymphoma-like PTLD. Due to the increasing number of organ transplantations, doctors of various specialties may encounter PTLD.

Gemcitabine treatment in pretreated cutaneous T-cell lymphoma: experience in 44 patients.

PURPOSE: To evaluate the efficacy and toxicity of gemcitabine, a novel pyrimidine antimetabolite with a low-toxicity profile and activity in several solid tumors, in patients with relapsed or refractory cutaneous T-cell lymphomas. PATIENTS AND METHODS: Between May 1997 and February 1999, 44 previously treated patients with mycosis fungoides (MF; n = 30) and peripheral T-cell lymphoma unspecified (PTCLU) with exclusive skin involvement (n = 14) were enrolled onto a two-institution, phase II trial and treated with gemcitabine. This drug was given on days 1, 8, and 15 of a 28-day schedule at a dose of 1,200 mg/m(2) intravenously over 30 minutes for a total of three courses. RESULTS: Of the 44 patients, five (11. 5%) achieved complete responses (CRs), 26 (59%) partial responses (PRs), and the remaining 13 showed no benefit from the treatment. Two of the CRs were histologically confirmed. The CR and PR rates were the same for patients with MF and those with PTCLU, respectively. No difference in terms of overall response rate was observed between relapsed and refractory patients. The median durations of CR and PR were 15 months (range, 6 to 22 months) and 10 months (range, 2 to 15 months), respectively. Treatment was well tolerated; hematologic toxicity was mild, and no nausea/vomiting or organ toxicity was recorded. CONCLUSION: The results of the present phase II study show activity of gemcitabine as a single agent in patients with pretreated cutaneous T-cell lymphoma. Further studies that use gemcitabine alone or in combination with other drugs in earlier stages of the disease are needed.

Anaplastic large-cell lymphoma: clinical and prognostic evaluation of 90 adult patients.

PURPOSE: During the last few years, the application of CD30 monoclonal antibodies has led to the identification of a new lymphoma entity, termed anaplastic large cell lymphoma (ALCL). This tumor includes four distinct histologic subtypes, among which the Hodgkin's-like/Hodgkin's-related one (ALCL-HL) shares morphologic and phenotypic features with Hodgkin's disease (HD). PATIENTS AND METHODS: From September 1988 to October 1993, 90 ALCL patients were treated with third-generation chemotherapy regimens (either vincristine, cyclophosphamide, fluorouracil, cytarabine, doxorubicin, methotrexate with leucovorin, and prednisone [F-MACHOP] or methotrexate with leucovorin, doxorubicin, cyclophosphamide, vincristine, prednisone, and bleomycin [MACOP-B]) during the course of an Italian multicentric randomized trial on high-grade non-Hodgkin's lymphomas (HG-NHL). In particular, 47 patients had ALCL of the common type (ALCL-CT) and 43 ALCL-HL. Null phenotype was the most common (39.8%), while T-cell, B-cell, and hybrid forms accounted for 35.5%, 22.2%, and 2.5%, respectively. RESULTS: Complete remission (CR) was achieved in 66 of 90 (73.5%) patients (33 of 47 [70%] with ALCL-CT and 33 of 43 [77%] with ALCL-HL). The majority of the patients in CR (56.5%) were alive and well at a median follow-up time of 38 months; no significant differences were observed between the two histologic groups, with the rate of complete responders being 49% and 65% in ALCL-CT and ALCL-HL, respectively. The probability of relapse-free survival (RFS), projected at 63 months, was 67% for ALCL-CT and 82% for ALCL-HL. The risk of lower CR and RFS rates was associated with the presence of bulky disease, advanced stage, and B symptoms. CONCLUSION: The data of the present study confirm that ALCL responds to third-generation chemotherapy regimens similarly to other aggressive malignant lymphomas in terms of both CR and RFS rates.

Early autologous stem-cell transplantation versus conventional chemotherapy as front-line therapy in high-risk, aggressive non-Hodgkin's lymphoma: an Italian multicenter randomized trial.

PURPOSE: To evaluate the role of early intensification with high-dose therapy (HDT) and autologous stem-cell transplantation (ASCT) as front-line chemotherapy for patients with high-risk, histologically aggressive non-Hodgkin's lymphoma (NHL). PATIENTS AND METHODS: We planned a multicenter, randomized trial to compare a conventional chemotherapy regimen of methotrexate with leucovorin rescue, doxorubicin, cyclophosphamide, vincristine, prednisone, and bleomycin (MACOP-B; arm A) with an abbreviated regimen of MACOP-B (8 weeks) followed by HDT and ASCT (arm B) for intermediate-high-risk/high-risk patients (according to the age-adjusted International Prognostic Index). From September 1994 to April 1998, 150 patients with aggressive lymphoma were enrolled onto the trial. Seventy-five patients were randomly assigned to arm A and 75 patients were randomly assigned to arm B. In both arms, involved-field radiation therapy (36 Gy) was delivered to the site of bulky disease. RESULTS: The rate of complete response was 68% in arm A and 76% in arm B (P = not significant [NS]). Three toxic deaths (4%) occurred in arm B and one (1%) occurred in arm A (P = NS). In arm B, 30 patients (40%) did not undergo HDT and ASCT. According to the intention-to-treat analysis at a median follow-up of 24 months, 5-year overall survival probability in arms A and B was 65% and 64% (P =.95), 5-year progression-free survival was 49% and 61% (P =.21), and 5-year relapse-free survival was 65% and 77% (P =.22), respectively. CONCLUSION: Abbreviated chemotherapy followed by intensification with HDT-ASCT is not superior to conventional chemotherapy in patients with high-risk, aggressive NHL. Additional randomized trials will clarify whether HDT-ASCT as front-line therapy after a complete course of conventional chemotherapy improves survival in this group of patients.

Clinical efficacy and antiangiogenic activity of thalidomide in myelofibrosis with myeloid metaplasia. A pilot study.

Increased neoangiogenesis has been reported in myelofibrosis with myeloid metaplasia (MMM). Thus we studied the effects of thalidomide, an antiangiogenic drug, in 12 MMM patients. Before treatment, all the cases showed a significantly increased micro-vessel density (MVD); in all eight tested cases bFGF and VEGF plasma levels were higher than controls. All patients presented disease progression in the last 3 months with standard therapy, regarding splenomegaly, anemia and/or thrombocytopenia and/or hyperleukocytosis. Thalidomide was administered at daily doses increasing from 100 to 600 mg. Eleven out of 12 patients were evaluable. No progression of disease was seen during the treatment in any case. In particular, spleen size decreased in 7/11 patients, anemia improved in 3/4 (two are now transfusion independent), thrombocytopenia in 2/2 and hyperleukocytosis in 2/5 patients. Side-effects were frequent, although not severe. After treatment, VEGF and bFGF plasma levels varied widely and in selected cases decreased. In particular, VEGF and/or bFGF decreased in 4/5 responders and in 1/3 non-responders. Moreover, MVD significantly decreased in all the responders evaluated after treatment. We conclude that thalidomide is a feasible therapy in MMM patients and looks promising at least to control the growth progression of disease.

Beta-HCG aberrant expression in primary mediastinal large B-cell lymphoma.

We report on a primary mediastinal large B-cell lymphoma with aberrant expression of beta-human chorionic gonadotropin (beta-hCG). The patient, a 33-year-old man, had cough, dyspnea, fever, superior vena cava syndrome, and a mediastinal bulky tumor. A biopsy showed that the latter was characterized by large cells, sclerosis, and compartmentalization. The neoplastic elements expressed CD45, CD20, CD79a and, partially, CD30, whereas they were negative for CD3, epithelial membrane antigen and cytokeratins. Surprisingly, they displayed a clear-cut positivity for beta-hCG. The remaining oncofetal markers applied (PLAP and alpha1-fetoprotein) were negative. Electron microscopy demonstrated the presence of numerous nuclear pockets and the lack of intercellular junctions. DNA analysis by polymerase chain reaction showed clonal rearrangement of Ig heavy-chain genes. The patient responded promptly to the administration of MACOP-B. To the best of our knowledge, this is the first example of B-cell lymphoma showing positivity for beta-hCG; a similar aberrant expression was previously observed only in three Japanese patients with human T-cell lymphotropic virus type I+ adult T-cell lymphoma/leukemia. Because primary mediastinal large B-cell lymphoma has in the past been frequently confused with germ cell tumors, pathologists should be aware of possible beta-hCG expression by lymphomatous cells to avoid the risk of misdiagnosis.

Malignant lymphoma involving the mandible. Clinical, morphologic, and immunohistochemical study of 17 cases.

We present 17 cases of non-Hodgkin's lymphoma of the mandible, collected over a span of 10 years. Clinically, the patients showed a male:female ratio of 1:2.4 and a mean age of 60.6 years. Swelling was the most common symptom. In 11 of 17 patients, the disease presented in stage I. Radiotherapy alone was employed in 11 patients, in conjunction with chemotherapy in 5 patients, and was preceded by surgery in the remaining case. At this writing ten of the subjects are still alive, five died following progression of the disease, and two were lost during follow-up while in complete remission. Histopathology revealed 15 B-cell lymphomas (1 centroblastic/centrocytic, nine centroblastic, one Burkitt's, two immunoblastic, and two lymphoblastic) and two peripheral T-cell lymphomas (pleomorphic). The above diagnoses were confirmed by immunohistochemical analysis with a wide panel of reagents against fixative-resistant molecules. Our data suggest that (a) lymphomas of the mandible are principally represented by high-grade B-cell varieties (88%); (b) primitive T-cell lymphomas (here documented for the first time) have the same incidence in the mandible as they have in lymph nodes; and (c) immunohistochemistry, besides confirming histogenetic interpretations based on morphologic findings, provides the key to the differential diagnosis from malignant large-cell nonlymphoid tumors.

Cryoglobulins.

Serum cryoglobulins are found in a wide spectrum of disorders but are often transient and without clinical implications. Monoclonal cryoglobulins are usually associated with haematological disorders, whereas mixed cryoglobulins are found in many infectious and systemic disorders. So called essential mixed cryoglobulinaemia shows a striking association with hepatitis C virus (HCV) infection (> 90%). It is a systemic vasculitis (leucocytoclastic vasculitis) with cutaneous and multiple visceral organ involvement. Chronic HCV infection can lead to a constellation of autoimmune and neoplastic disorders. In this review, the aetiology, diagnosis, disease heterogeneity, and treatment of cryoglobulinaemia are discussed.

Retinoblastoma (RB1) gene product expression in breast carcinoma. Correlation with Ki-67 growth fraction and biopathological profile.

AIMS: To investigate the expression of retinoblastoma protein (pRb) in invasive breast tumours and compare its expression with the major biopathological prognostic indicators to identify more aggressive subgroups. MATERIAL: Archival paraffin embedded tissues from 153 consecutive primary breast carcinomas. METHODS: pRb, Ki-67, and oestrogen receptor/progesterone receptor proteins were identified by immunohistochemistry and score values were recorded by image cytometric analysis; p53 and EGFr expression was also evaluated. RESULTS: pRb scores correlated strongly with proliferation activity as determined by Ki-67 staining. Positive relations were also observed between pRb scores, tumour size, nuclear and histological grade, and oestrogen receptor/progesterone receptor content, while abnormal p53 accumulation was not associated with pRb expression. Among the high proliferating carcinomas it was possible to identify 13 cases with loss of pRb expression. CONCLUSIONS: pRb expression paralleled proliferative activity in the majority of breast carcinomas examined, suggesting that in these cases the protein behaves normally in regulating the cell cycle. Conversely in cases with loss of pRb immunostaining, the combined expression of specific highly aggressive factors (EGFr and p53 expression, oestrogen receptor/progesterone receptor negative status, and high K67) seems to characterise a more aggressive phenotype showing growth advantage and cellular "progression" rather than significant nodal involvement.