Nasal T-cell lymphoma associated with hemophagocytic syndrome

Lymphoma-associated hemophagocytic lymphohistiocytosis (LA-HLH): a scoping review unveils clinical and diagnostic patterns of a lymphoma subgroup with poor prognosis

Hemophagocytic lymphohistiocytosis (HLH) is a severe hyperinflammatory syndrome driven by pathologic activation of cytotoxic T-lymphocytes and macrophages. Despite advances in diagnostics and management, adult patients with lymphoma-associated HLH (LA-HLH) harbor particularly poor prognosis and optimal treatment remains challenging. As systematic data on LA-HLH are scarce, we aimed to synthesize research evidence by thorough analysis of the published literature in PubMed (MEDLINE-database) within the context of a scoping review. Of 595 search results, 132 articles providing information on 542 patients were reviewed and analyzed. Median patient age was 60 years (range, 18-98) with male predominance (62.7%). B- and T-NHL were equally represented (45.6% and 45.2%), Hodgkin's lymphoma was reported in 8.9% of the cases. The majority of patients (91.6%) presented in Ann-Arbor-Stages III and IV, and bone marrow infiltration was observed in a significant proportion of patients (61.5%). Soluble CD25 levels were markedly elevated (median 10,000 U/ml), with levels beyond 10,000 U/ml indicating unfavorable prognosis for 30-day and overall survival. 66.8% of the patients died after median 5.1 months. LA-HLH remains a clinical challenge requiring specialized management. Timely diagnosis and appropriate lymphoma-specific treatment are of utmost importance to enhance patient outcomes.

Epstein - Barr virus positive T and NK-cell lymphoproliferations: Morphological features and differential diagnosis

The spectrum of Epstein-Barr virus (EBV)-positive T and NK-cell lymphoproliferations is broad and ranges from reactive self-limited disorders to neoplastic processes with a fulminant clinical course. EBV plays an important role promoting lymphomagenesis, although the precise mechanisms remain elusive. EBV-positive lymphoproliferative disorders (LPD) are more common in East Asia (China, Japan, Korea and Taiwan), and Latin America suggesting a strong genetic predisposition. The revised 2016 World Health Organization (WHO) lymphoma classification recognizes the following malignant NK- and T-cell lymphomas; extranodal NK/T-cell lymphoma, nasal type (ENKTCL), aggressive NK-cell leukemia (ANKL), and the provisional entity within the group of peripheral T-cell lymphoma, not otherwise specified (PTCL, NOS) "primary EBV-positive nodal T or NK cell lymphoma". Disorders presenting mainly in children and young adults include chronic active EBV infection (CAEBV) - systemic and cutaneous forms - which are not considered malignant disorders but were included in the WHO classification for the first time because of the differential diagnosis with other T- or NK-cell lymphomas. CAEBV, cutaneous form, includes hydroa vacciniforme-like LPD (HV-LPD) and severe mosquito bite allergy (SMBA). Finally, systemic EBV-positive T-cell lymphoma of childhood was recognized as lymphoma because of its fulminant clinical course. Given the shared pathogenesis of these disorders, overlapping features are common demanding a close clinical, morphological and molecular correlation for an accurate diagnosis. This review summarizes the clinical, histopathological and molecular features of EBV-associated T and NK-cell LPD, highlighting the main features that might aid in the differential diagnosis.

Frequent concomitant epigenetic silencing of the stress-responsive tumor suppressor gene CADM1, and its interacting partner DAL-1 in nasal NK/T-cell lymphoma

Nasal NK/T-cell lymphoma (NL) is a rare but clinically important entity of lymphoma. Its preferential incidence in Orientals but not Caucasians suggests possible genetic predisposition. 11q deletion is common in NL, indicating certain tumor suppressor genes (TSGs) at this locus involved in its pathogenesis. We investigated the expression and methylation of an 11q23.2 TSG, CADM1 (or TSLC1), and its partner DAL-1 (or EPB41L3) in NL. Methylation and silencing of CADM1 were detected in 2 NL and 4 of 8 (50%) of non-Hodgkin lymphoma (NHL) cell lines, but not in normal NK cells and normal PBMC. Absence of CADM1 protein was also detected in NL cell lines. 5-aza-2'-deoxycytidine (Aza) demethylation or genetic knockout of both DNMT1 and 3B genes restored CADM1 and DAL-1 expression. CADM1 methylation was further detected in 36 of 45 (80%) of NL tumors. Concomitantly, DAL-1 was epigenetically inactivated in NL cell lines and virtually all the tumors with methylated CADM1. A significant correlation between the methylation of both genes was found (p < 0.0001). Homozygous deletion of CADM1 was detected in only 3 of 18 (17%) of tumors. The stress-response of CADM1 was abolished when its promoter becomes methylated. Our results demonstrate a frequent, predominant epigenetic silencing of CADM1 and DAL-1 in NL, which likely play a synergic role in NL pathogenesis.

Primary ocular natural killer/T-cell lymphomas: clinicopathologic features and diagnosis

PURPOSE

Primary ocular natural killer/T-cell lymphoma (NKTL) is rare. This study aims to characterize the clinical manifestations, diagnosis and treatment methods of primary ocular NKTL.

METHODS

Clinical data of seven patients with ocular NKTL from 1982 to 2004 were collected. A morphologic, immunohistochemical and molecular analysis was undertaken.

RESULTS

Clinical manifestations and computed tomography of the patients were typical. LCA CD56 CD3epsilon Ki-67 granzyme B (GrB) and T-cell intracellular antigen-1(TIA-1) were mostly positive. Clonal T-cell-receptor gene rearrangements of five patients showed negative findings, and the detection of Epstein-Barr virus showed positive. All patients died 5 months to 28 months after presentation.

CONCLUSION

Ocular NKTL is a highly aggressive clinical course with poor prognosis. The diagnosis relies on clinicopathologic findings.

Periphere NK/T-Zell-Lymphome

Peripheral T-cell lymphomas comprise 8% of the malignant lymphomas in Germany. About 25% of these cases present primarily in extranodal localizations. Such localizations are typical for the respective disease and form the basis for the classification of extranodal peripheral T-cell lymphoma. The morphology, immunophenotype and lineage specificity of the tumor cells (originating from T- or NK-cells) is only secondary for the classification. Extranodal NK/T-cell lymphomas of the nasal type are characterized by an angiocentric growth pattern and large confluent areas of necrosis. In addition, there is a clonal infection by Epstein-Barr virus in the T-lymphocytes. In the differential diagnosis, B-cell lymphomas are more frequent at all localizations than T- or NK-cell lymphomas.

Aggressive Lennert's lymphoma: report of three cases in comparison to non-aggressive Lennert's lymphoma

The present article describes three cases of Lennert's lymphoma exhibiting aggressive clinical courses. These cases were accompanied by disseminated intravascular coagulation (DIC) or hemophagocytic syndrome (HPS). These cases were compared to non-aggressive type of Lennert's lymphoma. Of the three cases, two demonstrated involvement of the liver and the other possessed bone marrow involvement. In one patient, while a lymph node biopsy revealed Lennert's lymphoma histologically, a liver biopsy obtained 2 months later revealed a high-grade large cell cytotoxic T-cell lymphoma. Two of these cases showed HPS and the other exhibited DIC. All patients died within 1 year of diagnosis, with the shortest survival period being 1.5 months. Immunohistochemically, lymphoma cells were CD8+, CD4-, granzyme B+, and T-cell intracellular antigen-1 (TIA-1)+, showing a cytotoxic T-cell phenotype. Two cases demonstrated positive reactivity for Epstein-Barr virus in lymphoma cells by in situ hybridization. These cases were compared with eight cases of non-aggressive Lennert's lymphoma. In comparison to non-aggressive disease, these three cases displayed a higher percentage of Ki-67-positive cells. In conclusion it was found that a subset of Lennert's lymphoma cases share common features with high-grade cytotoxic T-cell lymphoma, indicating that Lennert's lymphoma may be part of the spectrum of cytotoxic T-cell lymphoma.

The pathology of NK-cell lymphomas and leukemias

Natural killer (NK) cell lymphomas and leukemias are a rare but clinically important group of neoplasms. Most of these tumors are aggressive, with a high rate of mortality. They include extranodal NK/T-cell lymphomas of nasal type and aggressive NK-cell leukemias. Both are Epstein-Barr virus (EBV) associated and show similar epidemiologic features. A closely related entity seen mainly in children is hydroa vacciniforme-like lymphoma, which also is EBV positive. EBV influences the pathophysiology of these tumors, through the induction of cytokines and chemokines. The differential diagnosis of NK-cell malignancies includes fulminant EBV-associated T-cell lymphoproliferative disorder, a condition referred to in the past as fatal infectious mononucleosis. Benign proliferations of NK cells can be seen in association with viral infection. The disease formerly referred to as blastic NK-cell lymphoma is now considered to be a malignancy derived from a dendritic cell precursor.

Sickle cell crisis associated with hemophagocytic lymphohistiocytosis

Sickle-beta(+) (beta(+)) thalassemia is a double heterozygous genetic disorder characterized by both a qualitative and quantitative abnormality. We present a case of an African American male who was first diagnosed with sickle cell disease (SCD) at the age 23 years when he presented with generalized bone pain, fever, and hepatosplenomegaly. Laboratory findings included thrombocytopenia, microcytic anemia, and markedly elevated ferritin. He was subsequently diagnosed with a sickle-beta thalassemia hemoglobinopathy. Findings in the bone marrow aspirate and biopsy were consistent with hemophagocytic lymphohistiocytosis (HLH). HLH resolved with the resolution of sickle cell bone pain crisis without use of immunosuppressive therapy. To the best of our knowledge this is the first documented case of HLH associated with sickle cell bone pain crisis.

Natural killer cell neoplasms: a distinctive group of highly aggressive lymphomas/leukemias

Natural killer (NK) cell neoplasms, which include extranodal NK/T-cell lymphoma (nasal and extranasal) and aggressive NK cell leukemia, are generally rare, but they are more common in people of Oriental, Mexican and South American descent. These neoplasms are highly aggressive, and show a strong association with Epstein-Barr virus. Extranodal NK/T-cell lymphoma most commonly affects the nasal cavity and other mucosal sites of the upper aerodigestive tract. Patients present with nasal obstruction or midfacial destruction. Despite the early stage of disease at presentation, overall survival is poor. Patients with the extranasal form of the lymphoma often present with high-stage disease, commonly involving the skin, gastrointestinal tract, testis, and soft tissue, and the prognosis is even worse. Histologically, the lymphoma can show a broad cytologic spectrum, but apoptosis, necrosis, and angioinvasion are common. The most common immunophenotype is CD2(+), surface CD3(-), cytoplasmic CD3(+), CD56(+). Based on currently available data, treatment of nasal NK/T-cell lymphoma should consist of radiotherapy, with or without multiagent chemotherapy. More research is required to ascertain the role of high-dose chemotherapy with stem cell rescue and that of non-multidrug resistance-related chemotherapeutic agents. Aggressive NK cell leukemia affects younger patients, who present with poor general condition, fever, and disseminated disease; they often die within a short time from systemic disease or complications such as multi-organ failure. The peripheral blood and bone marrow show atypical large granular lymphocytes, which exhibit an immunophenotype similar to that of extranodal NK/T-cell lymphoma. Aggressive NK cell leukemia must be distinguished from T-cell large granular lymphocyte leukemia and indolent NK cell lymphoproliferative disorder, both of which are indolent.

A case of NK/T-cell lymphoma complicated by a squamous cell carcinoma of hard palate during combination chemotherapy and radiation therapy

NK/T-cell lymphoma, which often shows an angiocentric growth pattern, is a distinct clinicopathologic entity highly associated with Epstein-Barr virus. The disease is characterized by a destruction of the upper respiratory tract, particularly the nasal cavity, palate and paranasal sinuses. Interestingly, NK/T-cell lymphoma is closely linked to a variety of complications, such as hemophagocytic syndrome, second primary cancer, sepsis and bleeding. Here we report a case of a 50-year-old man diagnosed initially as NK/T-cell lymphoma of the oropharynx and who developed a second primary carcinoma of the hard palate during combination chemotherapy and radiation therapy.

A clinicopathological study of 20 patients with T/natural killer (NK)-cell lymphoma-associated hemophagocytic syndrome with special reference to nasal and nasal-type NK/T-cell lymphoma

We describe the clinicopathological features of 20 patients with T/natural killer (NK)-cell lymphoma-associated hemophagocytic syndrome (T/NK-LAHS). These patients were categorized into 2 groups according to the onset of hemophagocytic syndrome (HPS). Group 1 developed HPS during the clinical course, typically at the terminal phase of the disease. This group consisted of 7 patients with extranodal lymphoma arising in the nasal cavity, paranasal cavity, tonsils, or skin at presentation. In 5 of these patients, the preferred diagnosis was nasal and nasal-type NK/T-cell lymphoma, whereas the disease diagnoses in the remaining 2 patients were peripheral T-cell lymphoma of unspecified type and angioimmunoblastic T-cell lymphoma, respectively. Group 2 consisted of 13 patients whose disease corresponded to so-called malignant histiocytosis-like lymphoma, which is characterized by HPS at the initial presentation and the infiltration of the liver, spleen, and/or bone marrow without tumor formation. Nine of these 13 cases were found to have common histopathological features: CD56+, Epstein-Barr virus positivity, cytotoxic molecules, and nasal-type NK/T-cell lymphoma. The very poor prognosis of T/NK-LAHS may be partly explained by the finding that nasal and nasal-type NK/T-cell lymphoma, which is resistant to standard chemotherapy, made up the highest percentage (70%) of the cases.

Bone marrow involvement in lymphomas with hemophagocytic syndrome at presentation: a clinicopathologic study of 11 patients in a Western institution

Hemophagocytic syndrome (HPS) is a clinicopathologic syndrome that can reveal a non-Hodgkin's lymphoma. The pathologic features of lymphoma associated with HPS remain ill defined. We studied 11 lymphomas associated with HPS on initial bone marrow biopsies, consecutively diagnosed during a 6-year period in a Western institution. There were seven diffuse large B-cell lymphomas (DLBCLs), three T-cell lymphomas (one peripheral T-cell lymphoma unspecified, two hepatosplenic gammadelta T-cell lymphomas [HS gammadeltaTLs]), and one aggressive NK-cell lymphoma/leukemia (NKL). These lymphomas shared common clinicopathologic features with a systemic presentation, a poor outcome (nine patients died within 2 years), and a mild interstitial lymphoid infiltrate of the bone marrow at presentation in nine patients. This equivocal lymphoma infiltrate was blending with normal hematopoietic cells, and CD20 and CD3 immunolabelings were essential for its detection. A high number of reactive T (CD3+) cells, most often with a predominant cytotoxic (CD8+ TiA1+) phenotype, was present in all DLBCLs. By in situ hybridization, Epstein-Barr virus was detected in neoplastic cells of three cases (one DLBCL, one HS gammadeltaTL, and one NKL), which also showed serum viral DNA. Polymerase chain reaction studies disclosed HHV6 DNA sequences in tumor tissues of two DLBCLs, whereas HHV8 DNA was not detected. Because tumor mass indicative of lymphoma was not striking in most patients, bone marrow biopsy appears to be of great value for the diagnosis of an HPS-associated lymphoma, which may be, in Western patients, of B- as well as T- or NK-cell type. Immunostaining for CD3 and CD20 is essential to identify the common subtle lymphoma involvement. Together with a better understanding of the pathogenic processes, an early diagnosis may improve the prognosis of HPS-associated lymphoma.

Angiocentric lymphoma of the head and neck: patterns of systemic failure after radiation treatment

PURPOSE

To investigate the patterns of systemic failure and the clinical outcome in patients with angiocentric lymphoma of the head and neck who were treated with radiation alone, and to discuss the optimal mode of treatment for these patients.

PATIENTS AND METHODS

We reviewed the records of 92 patients with stage I or II angiocentric lymphoma who were treated at Yonsei Cancer Center between 1976 and 1994. All patients were treated with involved-field irradiation. Radiation doses ranged from 40 to 60 Gy (median dose, 50.4 Gy). Treatment response, patterns of treatment failure including systemic failure, and clinical outcome after radiation treatment were analyzed.

RESULTS

The most frequently involved site was the nasal cavity, either alone or in conjunction with other sites. In 16 patients (17.4%), angiocentric lymphoma was accompanied by cervical lymphadenopathy. Disease was classified as stage I in 62 patients (67.4%) and stage II in 30 patients (32.6%). After completion of radiation treatment, 61 patients (66.3%) achieved a complete response and 16 (17.4%) a partial response. Half of the patients (50.0%) ultimately experienced local recurrence with or without other components of failure, whereas regional failure was relatively uncommon (10.9%). Systemic failure occurred in 25.0% of patients during follow-up. Six patients had histologic findings identical to those at the time of the original disease (group I), whereas four patients exhibited morphologic features of frank lymphomas (group II). The majority of patients with systemic relapse had the predilection sites for widespread extranodal involvement, such as the skin, brain, lung, gastrointestinal tract, or testes. In addition, seven patients died from various medical illnesses or immunologic disorders, including hemophagocytic syndrome and second primary cancers (group III). After a median follow-up of 56 months, the overall survival and disease-free survival rates for all patients were 40.1% and 37.8%, respectively. All patients except one with systemic failure died within 1 year.

CONCLUSION

Treatment with radiation alone had suboptimal results, partly because of the occurrence of a variety of systemic failure with diverse clinicopathologic features. Given the frequent occurrence of systemic failure after radiation treatment, we believe that the multimodality treatment approach containing more effective chemotherapeutic agents should be incorporated in the treatment of angiocentric lymphoma confined to the head and neck.

[Etiological aspects of reactive hemophagocytoses: retrospective study in 99 patients]

We describe the causes of reactive hemophagocytic process in a retrospective study including 99 patients. The main diagnosis were: lymphomas (18 cases), pyogenic bacteria infections (15 cases), herpes virus infections (12 cases), other infections (multiple, parasitic, fungal, mycobacterial, unidentified) (11 cases), acute hepatitis (five cases), systemic lupus erythematosus (three cases). We also found numerous other diseases involving the reticuloendothelial system. The cause remained undetermined in 16 cases. Lymphoma accounted for 64% of the cases in previously healthy patients who had been febrile for more than 10 days at the time of the diagnosis of reactive hemophagocytic process, and for 31% in HIV-positive patients. Lymphomas were rare (5%) in non HIV-positive, immunosuppressed patients. In this setting and in previously healthy patients who had been febrile for less than 10 days, infectious diseases were widely dominant (respectively 60% and 86% of the cases). Those were mainly due to pyogenic bacteria and to herpes virus. A rapidly fatal evolution occurred in some cases of lymphomas-related hemophagocytic process. These data support the choice of aggressive investigations in order to diagnose lymphoma in previously healthy patients presenting with reactive hemophagocytic process who have been febrile for more than 10 days, and in selected HIV-patients. Such a procedure is not recommended in the other cases.

Upregulation of tumor necrosis factor-alpha gene by Epstein-Barr virus and activation of macrophages in Epstein-Barr virus-infected T cells in the pathogenesis of hemophagocytic syndrome

A potentially fatal hemophagocytic syndrome has been noted in patients with malignant lymphomas, particularly in EBV-infected T cell lymphoma. Cytokines, such as interferon-gamma (IFN-gamma), TNF-alpha, and IL-1alpha, are elevated in patients' sera. To verify whether infection of T cells by EBV will upregulate specific cytokine genes and subsequently activate macrophages leading to hemophagocytic syndrome, we studied the transcripts of TNF-alpha, IFN-gamma, and IL-1alpha in EBV-infected and EBV-negative lymphoma tissues. By reverse transcription PCR analysis, transcripts of TNF-alpha were detected in 8 (57%) of 14 EBV-infected T cell lymphomas, higher than that detected in EBV-negative T cell lymphoma (one of six, 17%), EBV-positive B cell lymphoma (two of five, 40%) and EBV-negative B cell lymphomas (one of seven, 14%). Transcripts of IFN-gamma were consistently detected in T cell lymphoma and occasionally in B cell lymphoma, but were independent of EBV status. IL-1alpha expression was not detectable in any category. Consistent with these in vivo observations, in vitro EBV infection of T cell lymphoma lines caused upregulation of TNF-alpha gene, and increased secretion of TNF-alpha, but not IFN-gamma or IL-1alpha. Expression of TNF-alpha, IFN-gamma, and IL-1alpha was not changed by EBV infection of B cell lymphoma lines. To identify the specific cytokine(s) responsible for macrophage activation, culture supernatants from EBV-infected T cells were cocultured with a monocytic cell line U937 for 24 h. Enhanced phagocytosis and secretion of TNF-alpha, IFN-gamma, and IL-1alpha by U937 cells were observed, and could be inhibited to a large extent by anti-TNF-alpha (70%), less effectively by anti-IFN-gamma (31%), but almost completely by the combination of anti-TNF-alpha and anti-IFN-gamma (85%). Taken together, the in vivo and in vitro observations suggest that infection of T cells by EBV selectively upregulates the TNF-alpha expression which, in combination with IFN-gamma and probably other cytokines, can activate macrophages. This study not only highlights a probable pathogenesis for virus-associated hemophagocytic syndrome, but also suggests that anti-TNF-alpha will have therapeutic potential in the context of their fatal syndrome.

Bone marrow cytological findings in 4 dogs and a cat with hemophagocytic syndrome

Hemophagocytic syndrome or hemophagic histiocytosis was diagnosed in 4 dogs and 1 cat by evaluation of bone marrow aspirate smears. One of the dogs had a suspected infection with canine parvovirus and a confirmed infection with Salmonella spp, 2 dogs had presumptive diagnoses of myeloproliferative and lymphoproliferative disease, respectively, and 1 dog died without a diagnosis. The cat had hepatic lipidosis and lesions compatible with feline calicivirus infection. All animals had cytopenias involving 2 or more cell lines, and fragmented erythrocytes in the blood, along with mild to moderate increases in the number of macrophages in the bone marrow. Numerous marrow macrophages contained phagocytized hematopoietic cells. Other cytological features of the bone marrow were variable in each patient, but the degree of response in the blood was inadequate, even in those with bone marrow hyperplasia. The phagocytosis of hematopoietic elements did not appear to be caused by a primary immune disorder, but rather by the inappropriate activation of normal macrophages secondary to infectious, neoplastic, or metabolic diseases. These findings suggest that hemophagocytic syndrome may be an important factor in the development of cytopenias; the data also support the cytological evaluation of bone marrow aspirates as an aid in the diagnosis of hemophagocytic syndrome.

Hemophagocytic syndrome in Epstein-Barr virus-associated T-lymphoproliferative disorders: disease spectrum, pathogenesis, and management

The Epstein-Barr virus (EBV) has been shown to infect T lymphocytes and is associated with two recently recognized human T-lymphoproliferative disorders: childhood EBV-associated hemophagocytic syndrome (VAHS) representing a primary or active EBV infection of T cells in young children, and the EBV-containing T cell lymphoma in adults predominantly affecting the nose, skin and gastrointestinal tract. In both diseases, hemophagocytic syndrome (HS) accounts for the major cause of mortality. The patients developing HS share common clinicopathologic features such as fever, skin lesions, lung infiltrates, hepatosplenomegaly with jaundice, cytopenias, and coagulopathy. The liver, spleen, lymph nodes, and bone marrow usually show florid histiocytic proliferation with hemophagocytosis in addition to the proliferation of atypical T lymphocytes or immunoblasts. The HS in T cell lymphoma may develop simultaneously with initial lymphoma presentation, at tumor relapse, or even during remission. The cytokines, in particular tumor necrosis factor-alpha, released from the EBV-infected T lymphocytes are presumed to cause the histiocytic activation and the subsequent hemophagocytic process. Chemotherapy or antiviral agents fail to arrest the hemophagocytic process in both diseases. Immunomodulatory treatment incorporating etoposide and intravenous immunoglobulin, however, has been effective in the control of the progression of the hemophagocytic process in a substantial number of VAHS patients. Preliminary data suggest that bone marrow transplantation may be a promising way for eliminating both the virus and the proliferating T cells. Further investigations are mandatory for combating this aggressive hemophagocytic process in EBV-associated T lymphoproliferative disorders.

Non-Hodgkin's lymphoma of the sinonasal tract. A clinicopathologic and immunophenotypic study of 120 cases

BACKGROUND

Non-Hodgkin's lymphomas (NHLs) of the sinonasal tract are uncommon neoplasms that can be morphologically difficult to distinguish from destructive nonneoplastic processes or other malignant neoplasms in this site.

METHODS

From the files of the Otolaryngic Tumor Registry-Armed Forces Institute of Pathology from 1965 to 1992, 120 cases of NHL involving the sinonasal tract were selected for which clinical records and paraffin-embedded tissue blocks were available. The histologic features and immunophenotypic findings of each patient were examined, and follow-up data were obtained for 66 (55%).

RESULTS

The ratio of males to females was 1.35:1, and the ages ranged from 3 to 94 years (median, 59 years). Sixty percent of the cases of NHL occurred in the patients' sixth to eighth decades of life. Clinical presentations varied according to histologic type. The low grade lymphomas presented with a nasal cavity or paranasal sinus mass associated with obstructive symptoms. The high grade lymphomas were more likely to present with aggressive signs and symptoms including nonhealing ulcer, cranial nerve manifestations, facial swelling, epistaxis, or pain. Of note, the high grade B-cell lymphomas tended to present with soft tissue or osseous destruction, particularly of the orbit with associated proptosis, whereas the T-cell lymphomas were associated with nasal septal perforation and/or destruction. Sites of disease included the nasal cavity, one or more paranasal sinuses, or multiple regions within the sinonasal tract. Of patients who received adequate follow-up, nodal and extranodal dissemination were identified in a limited number (n = 11). Nodal dissemination occurred in cervical and axillary lymph nodes. Extranodal sites of involvement included the larynx, skin, liver, uvula, kidney, breast, lacrimal gland, testis, and prostate gland. There was a wide spectrum of morphologic types of lymphoma, classified according to the Working Formulation. Immunophenotypic analysis on paraffin embedded tissue sections of all patients demonstrated a B-cell to T-cell ratio of 1.18:1. Treatment primarily included radiotherapy and chemotherapy. Follow-up information was available for 66 (55%) patients ranging from 1 to 16 years (median, 3 years). Of these 66 patients, 24 (36.4%) died of disease, 17 (25.7%) are alive without disease, 13 (19.7%) are alive with disease, and 12 (18.2%) are dead of unrelated or unknown causes.

CONCLUSIONS

Non-Hodgkin's lymphomas of the sinonasal tract are heterogeneous diseases that can be clinically aggressive. The frequency of these lymphomas in the United States cannot be estimated accurately because all of our cases were of histologic slides submitted for consultations. There appears, however, to be a slight B-cell predominance in this population that previously has been observed, unlike in South America and Asia where the majority of cases have a T-cell phenotype.

Epstein-Barr virus infection in sinonasal non-Hodgkin's lymphomas

Sinonasal non-Hodgkin's lymphomas (SNHLs) of B- or T-cell immunophenotype have been associated with Epstein-Barr virus (EBV) infection of neoplastic lymphoid tissue. Nine SNHLs were investigated using immunohistochemistry, the polymerase chain reaction (PCR) for EBV genome and in situ hybridization (ISH) for EBV encoded RNAs (EBER), immunoglobulin (CI-gHR) and clonal T-cell receptor (CTC beta R) gene rearrangements. Eight cases were diagnosed as peripheral pleomorphic T-cell lymphomas (pPTCL). PCR showed the presence of EBV genome in eight cases; ISH for EBER led to the detection of positive cells in five cases. Late membrane protein (LMP) immunostaining was observed in three cases. No EBV positivity has been detected in control cases. The frequent association with EBV infection in the cases illustrated confirms the previous suggestions that EBV may have a role in the genesis of lymphomas of the sinonasal region.

Familial hemophagocytic lymphohistiocytosis associated with disseminated T-cell lymphoma: a report of two siblings

Two siblings with evidence of disseminated T-cell lymphoma at the time of diagnosis of familial hemophagocytic lymphohistiocytosis (FHL) are reported, an association which has not been described previously. The first child with typical clinical and laboratory features of FHL died shortly after admission, before diagnosis could be established. Retrospective analysis of autoptic tissue revealed marked hemophagocytosis as well as morphological and immunohistochemical features suggestive of disseminated T-cell lymphoma. In the second child, FHL was diagnosed in time. Subsequent histologic investigation of bone marrow biopsies displayed a focal infiltration by T-cell lymphoma. DNA hybridization studies provided evidence of a monoclonal T-cell receptor beta chain gene rearrangement. Following conventional chemotherapeutic induction for FHL, the patient received an allogeneic bone marrow transplant (BMT) from a related healthy donor. Currently, 17 months after BMT, the boy is in unmaintained remission from FHL and T-cell lymphoma. The current pathogenetic concepts for FHL and a possible relationship between T-cell lymphoma and FHL are discussed.

Clinicopathological spectrum of haemophagocytic syndrome in Epstein-Barr virus-associated peripheral T-cell lymphoma

Haemophagocytic syndrome (HS) is frequently observed in Epstein-Barr virus-associated peripheral T-cell lymphoma (EBV-PTCL) and represents a major cause of death. In this communication we have further analysed the spectrum of HS in 12 patients with EBV-PTCL. The patients could be divided into three groups according to the time of onset of HS during the clinical course of PTCL. Group I patients (four cases) had HS as the initial clinical manifestation. All four patients were initially suspected to have malignant histiocytosis (MH) but a MH-like PTCL was later diagnosed. Group II patients (six cases) developed HS at the time of lymphoma relapse. Four of them belonged to the angioinvasive type PTCL. Group III patients (two cases) developed HS at clinical remission; both were angioinvasive type PTCL. Nine patients had serological evidence suggesting active EBV infection. The clinical course after the onset of HS was generally fulminant in each group with a median survival of only 44d despite combination chemotherapy and/or empirical therapy with high-dose immunoglobulin and corticosteroids in six patients. In conclusion, HS represents a severe complication of EBV-PTCL. Although most patients develop HS at a time of active lymphoma, the syndrome may occur when the lymphoma is in remission. Because of the poor outcome, early diagnosis and a new modality of treatment for HS associated with EBV-PTCL should be pursued in future.

CD56 (NCAM)-positive malignant lymphoma

CD56, a natural killer cell marker reactive with the neuronal-cell adhesion molecule (NCAM), identifies a group of lymphomas with distinctive clinicopathologic features. The disease affects mostly middle-aged adults who often present with fever, skin rash and hepatosplenomegaly in the absence of peripheral lymphadenopathy. Extranodal involvement is common, particularly the skin, aerodigestive tract and central nervous system. Histologically, an angiocentric and angiodestructive pattern of infiltrate is often seen, but the cytological spectrum of the lymphoma cells is very broad. Cytoplasmic granules, however, are frequently found when Giemsa-stained cytologic preparations are examined. Immunologically, CD56-positive lymphomas can be sub-classified into CD3-positive (T-cell) and CD3-negative (probably true natural killer cell) subtypes. T-cell receptor gene rearrangement can be demonstrated in the former cases, but not in the latter. Clinically, CD56-positive lymphomas are aggressive neoplasms.

Bone marrow findings in malignant histiocytosis and/or malignant lymphoma with concurrent hemophagocytic syndrome

We examined bone marrow specimens from 19 patients with malignant histiocytosis (MH) and/or malignant lymphoma (ML) with concurrent hemophagocytic syndrome (HS) who suffered from high fever, hepatosplenomegaly, liver dysfunction, profound cytopenia, and erythrophagocytosis. There was little lymph-node enlargement or no tumor formation. The neoplastic cells in 3 patients exhibited histiocytes/macrophages phenotype with positive reactions for fluoride-sensitive nonspecific esterase, lysozyme and CD68 (KP1). Twelve other patients showed a T-cell (CD3) phenotype, in which 5 patients expressed CD30 (BerH2) as well. B-cell characteristics with CD20 (L26), CIg. nu lambda and gamma kappa were manifest in 2 patients, but indeterminate markers were found in the 2 remaining patients. Eighteen patients showed an infiltration of large neoplastic cells mainly with noncohesive interstitial growth pattern, ranging from 1.7% to 74.2% of the nucleated cells in the bone marrow. A large number of histiocytes/macrophages and dendritic cells was diffusely observed in 15 patients. Severely decreased hematopoiesis in all three series of hematopoietic cells was found in 16 patients. Bone marrow infiltration by the neoplastic cells and numerous reactive cells with erythrophagocytosis appears to be an important factor of profound cytopenia in patients of MH and/or ML with HS. The infiltrating pattern of the neoplastic and reactive cells in the bone marrow of MH and/or ML with HS was different from that of other types of peripheral T-cell ML, B-cell ML in high grade malignancy, and Hodgkin's disease. Cell characteristics and lineage of the neoplastic cells in MH and/or ML with HS are also discussed in this study.

The relationship of Epstein-Barr virus to infection-related (sporadic) and familial hemophagocytic syndrome and secondary (lymphoma-related) hemophagocytosis: an in situ hybridization study

Many cases of hemophagocytic syndrome have been associated with viral infections, particularly Epstein-Barr virus (EBV), but the pathogenesis of the syndrome remains unclear. We have examined lymph node, spleen, liver, and bone marrow sections from 12 cases, including four cases of proven or probable infection-related hemophagocytic syndrome (IHPS), three cases of familial hemophagocytic syndrome (FHPS), and five cases of secondary hemophagocytosis associated with T-cell malignant lymphoma (SHPC), for EBV RNA using a sensitive and specific in situ hybridization technique. Epstein-Barr virus RNA was detected in seven of 12 cases (58%), including three cases of IHPS, one case of FHPS, and three cases of SHPC. Numerous EBV-positive cells were detected in two cases of IHPS (in multiple anatomic sites) and in one case of FHPS (in the spleen). Diffuse EBV positivity also was noted within the neoplastic cells of one case of SHPC. Rare to occasional EBV-positive cells were found in multiple sites in another case of IHPS and within admixed, reactive lymphoid cells in two cases of SHPC. The results indicate that numerous EBV-positive cells can be identified in some cases of IHPS, FHPS, and SHPC, suggesting a pathogenetic role for the virus. However, the absence of EBV from a proportion of cases of IHPS and FHPS in this study suggests that other infectious agents also play a role in the pathogenesis of this syndrome.

Liver changes in reactive haemophagocytic syndrome

Hepatomegaly and deranged liver functions are common findings in reactive haemophagocytic syndrome (RHS). We report the findings of 12 fatal cases of RHS in which histological materials of the liver are available for study. The underlying diseases of these patients included lymphoma/leukaemia (6 cases), disseminated undifferentiated carcinoma of the ovary (1 case), disseminated nasopharyngeal carcinoma complicated by tuberculosis (1 case), adenovirus pneumonia (1 case), pneumococcal pneumonia (1 case), typhoid fever (1 case), and possible drug intoxication (1 case). Ten patients had involvement of the liver by the underlying disease process which contributed to the marked hepatic derangement. Non-specific reactive hepatitis, sinusoidal dilatation and steatosis resulting from systemic or local effects of the associated diseases and the haemophagocytosis also added to the high incidence of liver abnormalities. A diffuse Kupffer cell hyperplasia with haemophagocytosis is characteristic of the syndrome, as all the cases showed increased numbers of bland-looking histiocytes within the hepatic sinusoids and haemophagocytosis which was moderate to marked in 8 cases and mild in 4. Thus the finding of Kupffer cell hyperplasia with prominent haemophagocytosis in liver biopsy is indicative of an element of RHS and warrants clinical monitoring. Differential diagnoses of haemophagocytosis in liver are also discussed.

Histiocytic cytophagic panniculitis: molecular evidence for a clonal T-cell disorder

Histiocytic cytophagic panniculitis is a systemic disease of unknown etiopathogenesis that invariably involves the subcutaneous fat and is histologically characterized by phagocytosis of blood elements by histiocytes that appear to be benign. Immunophenotypic and genotypic studies of biopsy specimens of the lesions of a 58-year-old woman showed that the lymphocytic infiltrates accompanying the histiocytes in the subcutis were composed of clonal T-cells with rearrangement of the surface receptor gene. Our findings suggest that the primary abnormality in histiocytic cytophagic panniculitis may be a clonal T-cell proliferation.

Malignant lymphomas of the nasal cavity and paranasal sinuses. A clinicopathologic and immunohistochemical study

The clinicopathologic and immunohistological features of 20 Japanese patients with non-Hodgkin's lymphomas (NHLs) limited to the sinonasal area were studied using a broad panel of T- and B-cell markers on paraffin-embedded and fresh frozen tissue. All cases showed a diffuse growth pattern. Nine cases were B-cell lymphomas (immunoblastic n = 4, centroblastic n = 3, immunocytoma n = 1, centrocytic n = 1), and nine were T-cell lymphomas (pleomorphic medium and large cell n = 8, angioimmunoblastic n = 1). In two cases, the cell lineage could not be determined. No morphologic features of angiocentric/angiodestructive lymphoproliferative lesions or lymphoepithelial lesions in ductal or glandular epithelium were seen in our series. Eight (89%) of the nine T-cell tumors and four (44%) of the nine B-cell neoplasms involved both the nasal cavity and paranasal sinuses. Six of the nine T-cell neoplasms showed a clinical presentation of rhinitis, whereas all of the B-cell neoplasms showed tumor masses in the nasal cavity and/or paranasal sinuses. The two-year survival rate for T-cell lymphomas was poorer than that for B-cell lymphomas. The five-year survival of patients with NHLs involving both the nasal cavity and paranasal sinuses was also poorer than that of patients in whom NHLs were limited to the nasal cavity.

Hemophagocytic syndrome: a cause of pancytopenia in human ehrlichiosis

A 67-year-old white man with human ehrlichiosis infection complicated by pancytopenia, hemophagocytic syndrome, disseminated intravascular coagulopathy and septic shock is presented. The patient had been on a three-week camping trip to California, Colorado, Utah, and New Mexico. The diagnosis of human ehrlichiosis was confirmed by sixteen-fold rise in antibody titer to Ehrlichia canis, and supported by the characteristic cytoplasmic inclusions. Human ehrlichiosis should be considered in the differential diagnosis in patients with fever and cytopenia associated with hemophagocytosis. Pancytopenia associated with ehrlichiosis is transient; however, it may be severe, and appears to be associated with destruction of normal blood elements.

Anaplastic large cell Ki-1 lymphoma involving bone marrow: marrow findings and association with reactive hemophagocytosis

This report describes the bone marrow findings in four patients whose marrow was involved by anaplastic large-cell Ki-1 lymphoma, an uncommon event in this type of lymphoma. In the marrow aspirate smears, the involvement was subtle, and was in the form of isolated large cells with irregular nuclear configuration, coarse chromatin, prominent nucleoli, and basophilic cytoplasm which might be vacuolated. One case showed paradoxically massive involvement in the trephine biopsy taken from the same site as the marrow aspirate. Reactive histiocytic proliferation with hemophagocytosis was also present. Since marrow aspirate or biopsy may be the first pathologic specimen examined in patients having anaplastic large-cell Ki-1 lymphoma, it is important to be able to recognize the small population of neoplastic cells, which should lead to prompt treatment or further investigations as deemed necessary.

A clinicopathologic study of malignant lymphomas of the nose, paranasal sinuses, and hard palate, including cases of lethal midline granuloma

Malignant lymphomas of the nose, paranasal sinuses, and hard palate show marked clinicopathologic, immunologic, and prognostic diversity. The clinical features and pathologic spectrum of these lesions were studied in 20 cases (11 female and 9 male cases) with a mean age of 51 years at initial presentation. Malignant lymphomas of the large cell type were most frequently encountered (11/20). The next largest category was malignant lymphoma, diffuse, mixed small and large cell type (six of 20). Two thirds, 13 of 20 cases, had morphologic features suggestive of peripheral T-cell lymphomas. Necrosis, an angiocentric growth pattern, and epitheliotropism were found in nine, eight, and three cases, respectively. Of ten cases immunophenotyped on fresh-frozen or fixed, paraffin-embedded tissue sections, eight had a T-cell phenotype and two had a B-cell phenotype. Of 17 patients with sufficient follow-up data, ten are alive (median follow-up 33 months) and seven are dead (median survival 12 months). Patients with clinical Stages IE and IIE did not have a superior 5-year survival to those with more advanced disease. Histologic type also did not correlate with survival but this may be due to the aggressive histologic grade of the majority of cases and the retrospective nature of this study. The authors conclude that, despite the overall high-grade histologic type, the pathologic spectrum of malignant lymphomas involving this anatomic region is broad. Furthermore, some cases do not fit well into the National Cancer Institute (NCI) Working Formulation but more closely resemble the histologic features of peripheral T-cell lymphomas described in Japan.

Cutaneous relapse of nasal T-cell lymphoma clinically mimicking erythema multiforme

Lymphomatous involvement of skin usually manifests as plaques, maculopapules, papulonodules, tumorous masses or ulcerated eruptions. We report an unusual case in which the cutaneous relapse of nasal T-cell lymphoma clinically mimicked erythema multiforme by the abrupt onset of lesions and the presence of targetoid and vesicular lesions. Histologically, the lymphomatous involvement was predominantly periadnexal, with destructive infiltration of blood vessels, nerves and sweat glands. Early biopsy of all unexplained cutaneous eruptions in patients with malignant lymphoma is therefore recommended.

Peripheral T-cell lymphoma presenting as hemophagocytic syndrome

Three patients with peripheral T-cell lymphoma presenting with pyrexia, wasting, hepatosplenomegaly and pancytopenia in the absence of myelophthisic lymphomatous involvement are reported. Early in the course of the disease when there was no significant lymphadenopathy, these cases created enormous diagnostic confusion. Although the clinical features were suggestive of malignant histiocytosis (MH), marrow findings showed phagocytic histiocytes which did not appear atypical, and the criteria for diagnosis of MH could not be satisfied. Lymph node enlargement was detected only after 14, 5, and 8 weeks from the onset of symptoms, and the diagnosis of T-lymphoma was then made on lymph node biopsies. Treatment with multiple agent chemotherapy was attempted. Two patients died 3 days and 11 weeks after treatment was started and the third was lost to follow-up. In contrast with most of the cases reported in the literature, our cases show that a reactive hemophagocytic syndrome can be an early and prominent manifestation of an underlying T-cell lymphoma. Differentiation from other causes of hemophagocytic syndrome can be difficult and lack of histological proof of malignancy in the initial stage often delays definitive diagnosis and treatment.

Immunophenotypic analysis of sinonasal non-Hodgkin's lymphomas

A panel of paraffin effective antibodies recognizing B cells and T cells (LN-2, MB1, L26, MT1, UCHL1, kappa, lambda) was used to characterize the immunophenotypes of 26 sinonasal non-Hodgkin's lymphomas. Seventeen tumors were stage I, five were stage II, one was stage III, and three were stage IV. Nine lymphomas were classified morphologically as large cell, six were large cell immunoblastic, six were small cleaved cell, two were mixed small and large cell, two were small noncleaved cell, and one was lymphoblastic. None were follicular. Twenty-two lymphomas had a B cell immunophenotype, three were T cell neoplasms, and one was immunoreactive only for MT1. This predominance of sinonasal lymphomas with a B cell immunophenotype in patients residing in the United States contrasts with the almost exclusive occurrence of T cell sinonasal lymphomas in Chinese patients living in Hong Kong and Japanese patients residing in regions of Japan that are nonendemic for human T cell leukemia virus-1.

Immune deficiency with polymorphic reticulosis

A case of fatal polymorphic reticulosis, currently considered to be a peripheral T cell lymphoma, that was initially seen as a nasolabial swelling with a left lower lobe pulmonary nodule in a 40-year-old woman is reported. At autopsy, it was found to be associated with disseminated cryptococcosis and Pneumocystis carinii pneumonia associated with secondary severe immunodeficiency of unknown origin.

Histiocytic cytophagic panniculitis

Nineteen cases of histiocytic cytophagic panniculitis from our institution and from the literature were reviewed for their clinical and histopathologic features. All patients had cutaneous involvement consisting of cutaneous nodules and plaques that occasionally were ecchymotic and ulcerated and were characterized by infiltration of the subcutaneous tissue by large, benign histiocytes with cytophagic features. Thirteen of the patients had died (nine with hemorrhagic complications), four patients had a benign course with remission of the disease, and two patients responded to aggressive polychemotherapy. Immunohistochemical studies of paraffin-embedded tissue, performed in five cases, revealed a large number of infiltrating T cells in the subcutaneous inflammatory lesions.

Malignant lymphomas of the nasal cavity and paranasal sinuses

The incidence of malignant lymphomas in the nasal cavity and paranasal sinuses was found to be 0.17% of all malignant lymphomas and 0.44% of all extranodal malignant lymphomas registered in the Kiel Lymph Node Registry from 1972 to 1987. Fifty-nine cases of malignant lymphoma presenting in the nasal cavity and paranasal sinuses were investigated with morphological and immunological methods. The median age of the patients was 64.5 years, with a female predominance (m:f = 0.87:1). In the 59 cases a marked preponderance of B-cell lymphomas was found (centroblastic n = 15, immunoblastic n = 8, Burkitt's lymphoma n = 6, Immunocytoma n = 3, centrocytic n = 1, centroblastic/centrocytic n = 1, plasmacytic n = 11); only a small number (n = 5) was of T-cell lineage (pleomorphic types). Nine further cases could not be assigned with certainty to either the T or B cell system. Angiocentricity with infiltration and destruction of vessel walls by tumour cells was demonstrated only in the T-cell lymphomas; the B-cell lymphomas, in contrast, often surrounded and compressed blood vessels with intact endothelium. No similarity to malignant lymphomas of mucosa associated lymphoid tissue, such as those in the gastrointestinal tract, was detected.

Heterogeneous malignant non Hodgkin's lymphomas as a causative disorder in lethal midline granuloma

The present report describes the results of a combined morphological, enzyme- and immunohistochemical analysis of nine cases of malignant non Hodgkin's lymphomas (NHL) clinically presenting as lethal midline granuloma. In a previous report written before antibodies directed against B and T lymphocytes were available, a histiocytic origin of such neoplasms had been suggested. A panel of antibodies reactive with most B cells (L26, MB1, KiB3) and a majority of T cells (MT1, UCHL1) was applied on paraffin sections of formalin fixed tissues as well as antibodies directed against leukocyte common antigen (LCA), myeloid/histiocyte antigen (MAC 387), lysozyme, alpha-1-antitrypsin, alpha-1-antichymotrypsin, S-100 protein, prekeratin and immunoglobulin light chains. Enzyme histochemistry included tests for non-specific acid esterase, acid phosphatase, beta-glucuronidase and chloroacetate esterase. As a result, five T, two B and two unclassified (malignant histiocytosis probable) NHL were identified, indicating distinct heterogeneity of NHL as causative disorders in lethal midline granuloma.

Peripheral T cell lymphoma presenting primarily as lethal midline granuloma

This clinicopathologic study reports seven patients who primarily presented with ulcerative and destructive lesions of the upper aerodigestive tract and face, clinically consistent with so-called lethal midline granuloma (LMG). Histologically, the infiltrates were composed of atypical lymphoid cells that displayed angiocentricity and angiodestruction. In five patients, involvement of distant sites such as skin, lungs, lymph nodes, and bone marrow occurred, and in two cases, the disease remained localized. Immunomorphologic analysis, using monoclonal antibodies to frozen and paraffin sections, provided evidence for the diagnosis of peripheral T cell lymphoma (PTL) in all cases. The midline tumors were classified as diffuse mixed or diffuse large cell lymphoma occurred at distant sites. According to modern PTL classification systems, the lesions could be classified as pleomorphic T cell lymphomas. Those five patients who presented with or progressed to large cell lymphoma died within 18 months (mean, 7 months), whereas the two patients with localized disease are alive after 10 and 36 months, respectively. The size of the atypical lymphoid cells may be of prognostic significance since the large cell compartment seems to represent the major growth fraction in these PTLs.

Reactive histiocytic hyperplasia with hemophagocytosis in hematopoietic organs: a reevaluation of the benign hemophagocytic proliferations

Histiocytic hyperplasia with hemophagocytosis (HHH) is a relatively rare condition that has often been mistaken for a neoplastic disorder, but which most frequently represents a secondary reactive phenomenon whose associated risk factors have not yet been clearly defined. Histologic sections of hematopoietic organs (bone marrow, lymph nodes, and spleen) from 230 consecutive adults autopsies were reviewed to identify cases of HHH and to correlate them with clinical and autopsy findings. Moderate to severe HHH was present in the bone marrow in 102 and 230 cases, in the lymph nodes in 79 of 191 cases, and in the spleens of 16 of 209 cases. Recent blood transfusions, bacterial sepsis, major surgery, underlying disseminated malignancy, Candida sepsis, and viral infection were studied as potential risk factors. Both crude and adjusted analyses indicated a strong association between recent blood transfusions and the development of HHH in the bone marrow (P less than .0001). There was a marked dose-response relationship between number of units and the risk of HHH, with an adjusted risk ratio of 59.9 for five or more units compared with no transfusions. Bacterial sepsis was also associated with a significantly increased risk of HHH in the bone marrow in both the crude and adjusted analyses (adjusted risk ratio, 4.10; P = .0002). Major surgery and viral infection were only marginally associated with an increased risk for HHH (P = .03 and P = 0.06, respectively), and underlying disseminated malignancy and Candida sepsis did not appear to contribute any risk. Analyses for HHH in lymph nodes and spleen were similar to analysis for the bone marrow, but were somewhat less marked. The results of this study suggest that reactive HHH in hematopoietic organs may be far more common than has previously been acknowledged, and is most often multifactorial rather than related to a single underlying condition, with transfusions and bacterial sepsis constituting the most significant risk factors. Therefore, reactive HHH may represent a frequent secondary phenomenon in critically ill patients undergoing transfusions and should not be mistaken for an ominous sign or for the development of a superimposed malignancy.

Monoclonal antibodies reactive with normal and neoplastic T cells in paraffin sections

Without fresh or frozen tissue, it previously has been impossible to confirm the T-cell nature of reactive or neoplastic lymphoid cells. The availability of antibodies reactive with T cells in paraffin sections now allows retrospective analysis of a large number of cases. Two commercially available monoclonal antibodies, MT1 and MT2, were tested for their reactivities with T cells in a wide range of formalin-fixed, paraffin-embedded tissues, including 130 cases of immunologically characterized lymphoma. In reactive lymph nodes, MT1 stained the T-cell areas, whereas MT2 stained both the T-cell areas and mantle-zone B lymphocytes. MT1 stained 38 of 55 T-cell lymphomas (69.1%; 94.7% of cases from one hospital that used a shorter fixation time, and 55.6% of cases from another hospital that used a longer fixation time). MT2 stained only 6 (10.9%) of the T-cell lymphomas. Among the 74 cases of B-cell lymphoma, 3 (4.0%) were stained by MT1 and 30 (40.5%) by MT2.MT1 was also reactive with 3 of 4 cases of granulocytic sarcoma, as expected from its reactivity with normal granulocytes. Neither MT1 nor MT2 stained Reed-Sternberg cells or their variants in HodgKin's disease. We conclude that MT1 is a valuable marker for T cells, particularly when used with a panel of antibodies reactive with B cells in paraffin sections. MT2 is of limited value because of its cross-reactivity with many B-cell lymphomas.

Reactive hemophagocytic syndrome: a study of 7 fatal cases

Reactive hemophagocytic syndrome is a clinico-pathologic entity characterized by systemic proliferation of non-neoplastic histiocytes showing phagocytosis of hemopoietic cells, resulting in blood cytopenia. It is best known to be associated with virus infection, but other associated diseases have also been implicated. The clinical and pathological findings of 7 fatal cases are described. The syndrome affected both sexes of a wide age range, and all patients had fever. Significant laboratory findings were blood cytopenia, abrupt drop in the blood cell counts, deranged liver function tests and abnormal coagulation profile. The associated diseases were diverse: two patients had bacterial infection; two had peripheral T-cell lymphoma; one had disseminated undifferentiated carcinoma of the ovary; one had both tuberculosis and disseminated nasopharyngeal carcinoma, and one had no obvious underlying disease. It is postulated that lymphokines secreted by lymphoid cells or tumor cells may be responsible for the systemic activation of histiocytes. The differential diagnosis from malignant histiocytosis is discussed.