Prostatic acid phosphatase in carcinoid tumors. Immunohistochemical and immunoblot studies.

The immunohistochemical demonstration of prostatic acid phosphatase (PAcP) and/or prostate-specific antigen (PSA) has been accepted as being reliable in identifying metastatic adenocarcinoma of prostate origin. However, islet cell tumors, especially hindgut-derived carcinoid tumors, have occasionally been reported to be positive for PAcP. We therefore studied a series of carcinoid tumors of the lung and gastrointestinal tract immunohistochemically for PAcP expression by using two polyclonal antibodies and one monoclonal antibody. Thirty-three carcinoid tumors were examined. All five rectal carcinoids in the series showed convincing PAcP positivity with at least two of the three anti-PAcP antibodies. No significant PAcP positivity was observed in the remaining 28 foregut- and midgut-derived carcinoid tumors, except for weak focal positivity in one lung carcinoid. PSA antibody reacted negatively in all cases. Western blots of an aqueous cell lysate from one rectal carcinoid revealed protein bands in the region of 45-55 kd that immunoreacted with anti-PAcP antibodies, confirming the validity of the immunostains. These results suggest that PAcP positivity is common in rectal carcinoid tumors and that it most likely represents true PAcP expression. This seemingly aberrant protein expression may be explained by the shared cloacal derivation of the rectum and prostate, giving rise to cells with both endocrine and partial prostatic epithelial differentiation.

Extramedullary myeloid cell tumors. An immunohistochemical and morphologic study of 28 cases.

In an attempt to correlate the morphologic and immunophenotypic findings in extramedullary myeloid cell tumors (EMT), we studied 28 cases with a large panel of antibodies using paraffin section immunohistochemistry. A previous or concurrent diagnosis of acute myelogenous leukemia or chronic myelogenous leukemia was made in 25 cases. Six EMT were morphologically classified as well differentiated (WD-EMT), 17 as poorly differentiated (PD-EMT), and five as blastic EMT. The WD-EMT were easily recognized morphologically and displayed a relatively mature myeloid phenotype, with elastase, CD15, and CD68 positivity in all cases. On the other hand, the five blastic-EMT displayed no morphologic evidence of myeloid derivation, were completely negative for CD15, and were weakly positive for elastase in only one case. The PD-EMT, with a morphologic appearance that resembles large cell non-Hodgkin's lymphoma, variably expressed CD15 and elastase. CD68 and lysozyme were present in the majority of PD-EMT, with some variability, but were negative in most blastic-EMT. CD45 (LCA) was detected in 75% of all EMT and CD34 was positive in 36%; neither antigen was significantly associated with a specific morphology. CD30 reactivity was not evident in any case, but slight positive staining was seen with CD20 (L26) in one WD-EMT. CD43 (Leu 22) was the only antibody that was positive in 100% of cases; staining was always intense and widespread. Antimyeloperoxidase (MPO) was positive in all cases but two, both with a blastic morphology. We conclude that (a) an immunohistochemical panel including CD20, CD43, CD68, and MPO can successfully identify the vast majority (96%) of EMT in paraffin sections, and (b) there is an association between morphology and phenotype in these lesions.

The in-vitro response of CD2-positive acute myelogenous leukemia to proliferation and differentiation inducing agents.

Acute mixed lineage leukemias (MLL) are a heterogeneous group of acute leukemias that express morphologic and/or immunophenotypic features of more than one hematopoietic cell line. The ontogenetic significance of this mixed lineage expression is unclear. We therefore studied the conviction of the lineage commitment in a group of MLL by examining the in-vitro response of five CD2+ (E-rosette receptor) acute myelogenous leukemia (AML) to a panel of proliferation and differentiation-inducing agents. Three of the five CD2+ AML were TdT-positive. Antigen receptor gene studies revealed no rearrangements at either the T beta or immunoglobulin heavy chain gene loci in any case. When blast-enriched cell populations were placed in short term suspension cultures with PHA, IL-2, PHA + IL-2, GM-CSF or TPA, three of the leukemias responded in a similar fashion while the remaining two cases showed no response. In the three MLL that responded to the in-vitro culture manipulations, features indicative of differentiation along the monocytic lineage pathway were observed. This differentiation was not pronounced in the presence of the phorbol ester TPA, and was manifested by loss of CD2 and CD7 expression, continued expression of myeloid antigens, and the development by the blasts of morphologic and cytochemical characteristics of monocytic cells. None of the five MLL showed any evidence of induced maturation along the T-lymphocyte line of differentiation with any of the agents used. rGM-CSF was the only exogenously added agent to induce proliferation; the proliferative response was slight and was seen in only one of the five leukemias. Therefore, the phenotypic expression of CD2 and CD7 in blasts from MLL is not indicative of irreversible commitment to T-lymphocyte development. The in-vitro loss of T-cell antigens in concert with the development of monocytic features in three of the five CD2+ AML in this study suggests the leukemic cells were preferentially committed to a non-lymphoid lineage differentiation pathway.

Benign oncocytic endocrine tumor of the pancreas in a patient with polyarteritis nodosa.

An 8-cm mass in the tail of the pancreas was resected from a 40-year-old man with polyarteritis nodosa. The tumor cells contained abundant, finely granular, eosinophilic cytoplasm arranged in a gyriform pattern that suggested the tumor was an oncocytoma of the endocrine pancreas. Electron microscopy confirmed that the tumor was an oncocytoma by demonstrating tumor cell cytoplasm packed with mitochondria. Ultrastructural and immunocytochemical studies confirmed the neuroendocrine nature of the tumor by demonstrating dense-core, membrane-bound structures consistent with neurosecretory granules and neuron-specific enolase immunoreactivity. No immunoreactivity for insulin, glucagon, gastrin, somatostatin, or pancreatic polypeptide was found. No human chorionic gonadotropin alpha-chain immunoreactivity was detected. The patient is well without evidence of tumor five years after operation. The apparently benign behavior of the pancreatic endocrine oncocytoma reported here is in contrast to the malignant nature of another case reported recently.

Relationship between eosinophil density and T-cell activation markers in lymph nodes of patients with Hodgkin's disease.

Hodgkin's disease (HD) is characterized morphologically by a variable infiltration of tissues by eosinophilic granulocytes. The lesions also contain numerous T cells, predominantly of the CD4+ immunophenotype. To investigate whether the presence or absence of tissue eosinophilia is related to the immunophenotype of the T cells, we studied 43 cases of HD (28 nodular sclerosing, ten mixed cellularity, and five unclassifiable) for the relative numbers of lymphocytes positive for CD2, CD3, CD4, CD5, CD8, CD25, CD38, T9, TQ1, HLA-DR, and beta F1, and for the number of eosinophils in tissue sections. By univariate and multivariate analysis, we determined that there was an inverse relationship between the number of eosinophils and the presence of TQ1+ (P less than .0005) and CD25+ (P less than .0005) lymphocytes. In addition, we observed that TQ1 stained the Reed-Sternberg cells in these lesions. We also determined that the T cells expressed HLA-DR more frequently in the nodular sclerosis subtype than in other subtypes of HD (P less than or equal to .0001). We therefore conclude that the degree of tissue eosinophilia in the lymph nodes of patients with HD may be explained, at least in part, by the immunophenotype of the T cells present in the affected lymph nodes.

Cytokeratin expression in adrenocortical neoplasia: an immunohistochemical and biochemical study with implications for the differential diagnosis of adrenocortical, hepatocellular, and renal cell carcinoma.

The immunostaining patterns of adrenocortical tumors are not clearly defined, primarily due to their inconsistent expression of cytokeratins (CK). To address this issue and to investigate whether adrenocortical tumors can be immunohistochemically differentiated from histologically similar tumors arising from the kidney and liver, we studied four normal adrenal glands, two adrenocortical adenomas (ACAs), 31 adrenocortical carcinomas (ACCs), 37 renal cell carcinomas (RCCs), and 33 hepatocellular carcinomas (HCCs) with anti-CK antibodies AE1, CAM 5.2, UCD/PR10.11, 35BH11, PKK1, and Ks19.1, as well as antibodies to vimentin (VIM), epithelial membrane antigen (EMA), and HMFG-2. Normal adrenal cortical cells showed variable staining with all anti-CK antibodies on fixed and frozen sections. In contrast, only one of two fixed ACAs stained with a single anti-CK, although both neoplasms reacted with multiple anti-CK antibodies on frozen sections. Similarly, 20 of 31 fixed ACCs contained VIM, but only one tumor stained for CK; frozen sections of this and another, previously negative tumor, however, stained with most of the anti-CK antibodies tested. One-dimensional Western immunoblot analysis confirmed the presence of CKs 18 and 19 in two examples of normal adrenal cortex, one ACA, and the ACC immunohistochemically positive on fixed and frozen sections, with CK 19 identified in the ACC that was positive on frozen section alone. All fixed HCCs and most RCCs stained with multiple anti-CK antibodies (33 and 34 cases, respectively), with a proportion of tumors positive for VIM (six and 22 cases, respectively), EMA (seven and 30 cases, respectively), and HMFG-2 (15 and 28 cases, respectively). The results suggest that CK expression is diminished in most adrenocortical tumors to levels too low to be recognized following the deleterious effects of fixation. While the immunohistochemical absence of CK, EMA, and HMFG-2 in fixed sections in the majority of ACCs is distinctive, sufficient phenotypic overlap exists such that differentiation between RCC and HCC may not be possible in an individual case.

Monocytoid B-cell lymphoma. The biologic and clinical implications of peripheral blood involvement.

Monocytoid B-cell lymphoma (MBCL) is a newly recognized malignant lymphoma that shares clinical and pathologic features with other low-grade B-cell neoplasms, especially small lymphocytic lymphoma and hairy cell leukemia. However, although circulating malignant cells and bone marrow involvement are relatively common in small lymphocytic lymphoma and are characteristic features of hairy cell leukemia, MBCL in the peripheral blood and bone marrow rarely have been described. From 124 patients entered in the MBCL registry, three cases with peripheral blood involvement are described and the clinical and pathologic features in these patients are compared with those of other low-grade B-cell neoplasms. Monocytoid B-cell lymphoma was confirmed by lymph node biopsy in each case. Two patients had lymphocytosis at the time of presentation; the remaining patient presented with pancytopenia. For each patient, phenotypic studies of lymph node and peripheral blood revealed identical monoclonal surface immunoglobulin expression. The morphologic appearance of the circulating MBCL cells was different in each case, varying from a relatively homogeneous population of small lymphocytes to a heterogeneous collection of large and small lymphoid cells. The two patients with lymphocytosis also had extensive replacement of the bone marrow by MBCL; the third patient had diffuse infiltration by MBCL in a normocellular marrow. All three patients had advanced-stage (Stages III or IV) disease, and all required systemic chemotherapy for disease control. The two patients with lymphocytosis had relentless, progressive infirmity despite relatively aggressive treatment regimens. These patients ultimately died of lymphoma 13 and 18 months after initial diagnosis. The third patient is alive and well with stable disease 30 months after coming to the authors' institution. The clinical and pathologic features of the patients reported here reaffirms the placement of MBCL in the spectrum of low-grade B-cell neoplasms. However, unlike small lymphocytic lymphoma and hairy cell leukemia, MBCL only rarely undergoes leukemic conversion. Furthermore, it appears that peripheralization of MBCL occurs primarily in patients with advanced-stage disease and may be indicative of a relentless course and progressive disease despite aggressive chemotherapeutic intervention.

The human hematopoietic progenitor cell antigen (CD34) in vascular neoplasia.

The human hematopoietic progenitor cell antigen CD34 is synthesized and expressed by early normal hematopoietic progenitor cells and by many acute leukemias. Anti-CD34 antibodies also have been reported to stain blood vessels in tissue sections, and, more recently, CD34 mRNA has been detected in vascular endothelial cells. Therefore, the authors studied the diagnostic utility of immunohistochemical CD34 antigen detection in tumors of endothelial cell derivation and compared the results with stains for von Willebrand (vW) factor. A wide variety of epithelial and mesenchymal neoplasms also were examined to assess the specificity of CD34 for vascular neoplasia. Seven cases of angiosarcoma (seven of seven), five cases of Kaposi's sarcoma (five of five), and eight cases of epithelioid hemangioendothelioma (eight of eight) were moderately to strongly positive for CD34. This reactivity was equally intense in frozen sections, alcohol-fixed tissue, and formalin-fixed specimens. In many cases, the malignant endothelial cells stained more strongly than adjacent benign endothelium. Moreover, in most cases CD34 positivity was quantitatively and qualitatively stronger than staining for vW factor. Two cases of hemangiopericytoma (two of two) were CD34 positive but stained less intensely than the angiosarcomas, Kaposi's sarcomas, or hemangioendotheliomas. Five of six cases of hemangioma also stained positively for CD34; the nonreactive tumor in this group was the only one among 28 vascular neoplasms studied that was not reactive for CD34. In comparison, 9 of the 28 vascular tumors did not stain for vW factor. Three hundred fifty-seven tumors of nonvascular derivation also were examined for CD34 antigen expression. Focal light staining was seen in one pulmonary squamous cell carcinoma; moderate to intense staining was observed in half of the epithelioid sarcomas studied (8 of 16) and in a minority of leiomyosarcomas (3 of 22). These findings indicate that CD34 is a sensitive and relatively specific marker for neoplasms of vascular origin.

High-grade transformation of chronic lymphocytic leukemia and low-grade non-Hodgkin's lymphoma. Genotypic confirmation of clonal identity.

The abrupt appearance of a high-grade tumor in patients with low-grade malignant lymphoma usually is associated with an accelerated clinical disease course. The high-grade lymphoma may take a variety of histologic forms and often, but not always, represents evolution of the original low-grade disease, as shown by immunophenotypic or immunogenotypic studies. The authors describe the transformation of a variety of low-grade B-cell neoplasms to high-grade tumors in four patients. The initial diagnoses included chronic lymphocytic leukemia and mantle cell lymphoma in one patient each and low-grade follicular lymphoma in two patients. The high-grade tumors were classified as lymphoblastic lymphoma in one patient and small noncleaved cell lymphoma in two patients. The high-grade component manifests primarily in the peripheral blood as circulating blast-like cells consistent with large-cell lymphoma in the remaining patient. In each case, immunophenotypic studies showed identical monoclonal surface immunoglobulin expression on the low- and high-grade tumors. Immunoglobulin heavy chain gene and kappa light chain gene studies showed identical clonally rearranged bands in paired samples from three of the four patients, a finding indicative of clonal identity. Unexpectedly, dissimilar immunoglobulin light and heavy chain gene rearrangements were detected in the paired samples from one patient with previously diagnosed follicular lymphoma, making the relationship of the two tumors from this patient uncertain; however, additional Southern blot analysis of the bcl-2 gene showed identical rearrangements in both lesions. Furthermore, polymerase chain reaction across the t(14;18) major breakpoint region in both tumors amplified nucleotide fragments of identical size, confirming the clonal identity of the low- and high-grade lymphomas despite the divergent immunoglobulin gene studies. These studies show that low-grade malignant lymphomas of small lymphocytic, mantle cell, or follicular small cleaved cell types may assume high-grade morphologic characteristics, that this change is the result of transformation of the preexisting low-grade malignant neoplasm, and that this progression, like typical Richter's syndrome, is associated with a dramatically accelerated clinical course. In addition, these studies confirm previous reports that disparate immunoglobulin light and heavy chain gene rearrangements are not necessarily an indicator of different cellular origins, and additional genotypic studies occasionally may be required to show the clonal identity of the cell population involved in these morphologic transformations.(ABSTRACT TRUNCATED AT 400 WORDS)

Neural cell adhesion molecule (CD56)-positive acute myelogenous leukemia and myelodysplastic and myeloproliferative syndromes.

The CD56 antigen is normally expressed on natural-killer cells but has additionally been shown to be present on a variety of hematologic malignancies, including a subset of acute myelogenous leukemia (AML). There is disagreement, however, about its prognostic significance and its association with specific cytogenetic abnormalities. All clinical samples from June 1994, through September 1995, with increased myeloblasts were analyzed by multiparameter flow cytometry for anomalous expression of CD56. Patients with CD56+ blast cells were selected, and morphologic review was performed. Clinical information was obtained, and cytogenetic data were reviewed. Southern blot analysis to detect rearrangement of the mixed lineage leukemia (MLL) gene was performed when possible. The samples from 23 of 114 patients studied demonstrated anomalous expression of CD56 on myeloblasts, including patients with AML, myelodysplastic syndromes (MDS), and chronic myelogenous leukemia in blast crisis. The samples from 10 of 15 patients with CD56+ AML demonstrated at least partial monocytic differentiation. Dysplastic features were displayed in the samples of 12 patients. Correlation with specific cytogenetic abnormalities was not found. The MLL gene was rearranged in five of 18 patients. Seventeen patients have died, with a median survival of 4.6 months for patients with AML. Three have sustained a complete remission. One has findings of high-grade myelodysplastic syndrome. Two were unavailable for follow-up. Expression of CD56 was found in 20% of patients with increased myeloblasts, including patients with high-grade MDS, chronic myelogenous leukemia in blast crisis, and AML. This phenotype was associated with dysplasia, monocytic differentiation, and rearrangement of the MLL gene.

Myelodysplastic syndrome occurring after autologous bone marrow transplantation for lymphoma. Morphologic features.

Clonal karyotypic abnormalities characteristic of myelodysplastic syndrome (MDS) occur in up to 18% of patients who undergo autologous bone marrow transplantation (auto-BMT) for the treatment of lymphoma. Morphologic changes are often subtle and may not meet the French-American-British Cooperative Group criteria for MDS. We retrospectively assessed dysplastic changes in peripheral blood and bone marrow specimens obtained before and after transplantation from nine patients and correlated them with karyotype and survival. All patients had normal cytogenetic study results before transplantation and had clonal karyotypic abnormalities develop after auto-BMT. Four patients (with aggressive MDS) survived a short time and died of acute myelogenous leukemia or MDS-related complications, four (with indolent MDS) had a prolonged survival period, and one patient died of recurrent lymphoma. The group with aggressive MDS had significantly more bone marrow trilineage dysplasia before auto-BMT than did the group with indolent MDS or cytogenetically normal auto-BMT controls, suggesting that stem cell damage occurred before transplantation and was not detected by pretransplantation cytogenetic analysis. Comparatively greater dyserythropoiesis and dysmegakaryopoiesis were present after transplantation; these changes were similar to those seen in de novo MDS. Posttransplantation dysplasia in the group with indolent MDS was analogous to the atypia related to the transplantation process.

Rearrangement of the BCL-2 gene in follicular lymphoma. Detection by PCR in both fresh and fixed tissue samples.

Rearrangement of the BCL-2 gene is the molecular consequence of the t(14;18) chromosomal translocation, which is found in approximately 60-90% of follicular lymphomas. To investigate the ability of the polymerase chain reaction (PCR) to detect this rearrangement in fixed-tissue samples, we studied 48 cases of follicular lymphoma using DNA extracted from paired samples of fresh-frozen tissue and formalin-fixed, paraffin-embedded tissue. A standard phenol-chloroform DNA extraction method was used for both types of tissue. Rearrangements of the major breakpoint region (MBR) and minor cluster sequence (MCS) were examined. Three segments of the human beta-globin gene were also amplified to estimate the degree of DNA degradation in the fixed-tissue samples. PCR of fresh-tissue (intact) DNA revealed amplifiable products in 29 of the 48 follicular lymphomas (60%), whereas the fixed-tissue (degraded) DNA studies were positive in 24 (50%). MBR products were detected in 24 fresh-tissue samples, and varied from 80 bp to > 1.5 kb. Twenty of these cases yielded MBR products in the corresponding fixed-tissue DNA, ranging from 80 to 276 bp. Five fresh-tissue and four fixed-tissue samples produced MCS segments that ranged from 340 bp to 1.2 kb. Four of the five samples with no detectable MBR or MCS translocations using degraded DNA had products greater than 1.0 kb in the fresh-tissue studies. A 175-bp segment of the beta-globin gene was amplified in all 29 fixed-tissue samples; a 324 bp fragment was produced in 20 samples (69%), and a 676 bp segment was detected in 13 (45%).(ABSTRACT TRUNCATED AT 250 WORDS)

Detection of myeloperoxidase gene expression in minimally differentiated acute myelogenous leukemia (AML-M0) using in situ hybridization.

Acute leukemias containing > 3% myeloperoxidase (MPO)-positive blast cells, as detected cytochemically, are considered to be myelogenous in origin, regardless of the immunophenotypic markers expressed. Conversely, acute leukemias that express only myeloid antigens are also considered to be acute myelogenous leukemia (AML), even in the absence of MPO. These MPO-negative AMLs, designated AML-M0 in the FAB classification, currently require either immunophenotypic or electron microscopic studies for identification. To examine the association of MPO and myeloid antigen expression in AML, particularly at the early stages of myeloid cell differentiation, we have used in situ hybridization (ISH) to evaluate MPO gene expression in myeloid leukemia cell lines and a variety of well-characterized acute leukemias, including six cases of AML-M0. Strong positivity for MPO mRNA was detected in the myeloid leukemia cell line HL-60 and in 22 of 27 AMLs (three AML-M0, four AML-M1, eight AML-M2, five AML-M4, two AML-M5a). No MPO gene expression was detected in three AML-M0, one AML-M5a, one AML-M7, 5 acute lymphoblastic leukemia, the lymphoid cell lines Molt-4 and Namalwa, or in the early myeloid cell lines KG-1 and KG-1a. Ultrastructural studies for MPO activity were performed on four AML-M0; one leukemia showed both gene expression and cytochemical activity, whereas two others contained neither MPO transcripts nor enzyme. Weak MPO gene expression was evident in one AML-M0 that was negative for enzymatic activity by electron microscopy. These studies show MPO gene expression can be detected by ISH in about half of AML-M0, supporting their presumed myelocytic derivation.(ABSTRACT TRUNCATED AT 250 WORDS)

Acute monoblastic leukemia (FAB-M5b) with t(8;14)(p11;q11.1).

A case of acute monocytic leukemia (FAB-M5b) expressing natural killer cell-associated antigens containing a t(8;14)(p11;q11.1) is presented. We interpret this translocation to represent a variant of the t(8;16) previously reported in FAB-M5b. These findings support the contention that the 8p11 breakpoint site is the critical junction in the oncogenesis of acute monoblastic leukemia with differentiation.

Post transplant CD8+ gammadelta T-cell lymphoma associated with human herpes virus-6 infection.

Gammadelta T-cell lymphoma is a rare T-cell lymphoproliferative disorder that has been reported in both immunocompetent and immunocompromised persons. This report describes a forty eight year old patient who developed gammadelta T-cell lymphoma four years after undergoing living-related kidney transplantation. The lymphoma expressed CD2, CD3, CD7, CD8 and CD56, and the gammadelta T-cell receptor and did not express CD5, CD4 and the alphabeta T-cell receptor. In addition, HHV-6 was cultured from the patient's bone marrow, marking the first time that this virus has been associated with gammadelta T-cell lymphoma. Since all patients with gammadelta T-cell lymphoma described to date have responded poorly to standard combination chemotherapies, the patient was treated with the purine analogue 2-chlorodeoxyadenosine. While he responded transiently to treatment, long term remission was not achieved indicating that additional therapeutic approches still need to be developed, for the management of this disorder.

Myelodysplasia and acute myeloid leukemia occurring after autologous bone marrow transplantation for lymphoma.

Secondary hematopoietic disease manifesting as acute myeloid leukemia, myelodysplastic syndrome or clonal karyotypic abnormalities, has been recently recognized as a relatively frequent and potentially serious complication of autologous bone marrow transplantation for both Hodgkin's disease and non-Hodgkin's lymphoma. The available evidence suggests the disease results primarily from repeated exposure of the host stem cells to therapeutic agents before the time of transplant, but a conspiratory role for the transplantation procedure itself cannot be entirely excluded. Strategies to decrease the incidence of secondary hematopoietic disease include earlier stem cell harvest and/or transplantation, and the performance of screening karyotypic studies on the bone marrow prior to autologous grafting.

Craniocerebral plasmacytoma: MR features.

We report the MR imaging findings in two patients with solitary craniocerebral plasmacytoma, a benign plasma cell tumor that can arise from the skull, the dura, or, rarely, the brain. In both patients, the lesion was extraaxial and nearly isointense with gray matter on T2-weighted MR images, and diffusely enhanced after administration of contrast material, bearing some similarities to meningioma. A diagnosis of solitary craniocerebral plasmacytoma should be considered when a mass with these imaging features is seen, because total excision may not be necessary for this radiosensitive tumor.

Expression of interleukin-1 receptor antagonist protein in malignant lymphomas. An immunohistochemical study.

OBJECTIVE: Interleukin-1 (IL-1) receptor antagonist (IL-1ra) is a naturally occurring modulator of IL-1 that functions by competitively binding to IL-1 receptors without producing biologic effects. Interleukin-1 is believed to be a mediator involved in production of constitutional symptoms in patients with malignant lymphoma. Because we know of no study regarding IL-1ra expression in lymphomas, we tried to demonstrate the presence of IL-1ra in lymphomas using immunohistochemistry. DESIGN: Anti-IL-1ra monoclonal antibody was applied to paraffin sections of Hodgkin's disease and non-Hodgkin's lymphoma (NHL) with avidin-biotin complex method. RESULTS: Interleukin-1 receptor antagonist was found to be present primarily in benign reactive histiocytes in neoplastic tissue. Positivity for IL-1ra was found in 12 (67%) of 18 cases of Hodgkin's disease and 53 (29%) of 184 cases of NHL. The positivity rate varied in different subtypes of NHL. Three percent (1 in 30) of follicular small cleaved-cell lymphomas contained IL-1ra-expressing histiocytes, whereas 52% (17 of 33) of diffuse mixed-cell and 27% (12 of 44) of diffuse large-cell lymphomas contained IL-1ra-positive histiocytes. Nine of 13 (69%) cases of high-grade NHLs contained IL-1ra-expressing histiocytes. Among cases of NHL, the higher-grade NHL cases showed higher percentages of positivity. CONCLUSIONS: The findings further support the hypothesis that IL-1 may play a role in producing constitutional symptoms.

Detection of trisomy 8 by fluorescence in situ hybridization on bone marrow smears from patients with subtle myelodysplastic changes.

Trisomy 8 is the most common hyperdiploid numerical chromosomal abnormality that is found in myelodysplastic syndromes (MDSs). We explored the utility of combining fluorescence in situ hybridization interphase cytogenetics with routine morphologic analysis to characterize cases for which signs and symptoms were suggestive of MDS in which dysplastic changes were insufficient for a definitive diagnosis. Hybridization with a chromosome 8-specific centromeric probe was performed on bone marrow smears that were obtained from four patients with cytogenetically documented trisomy 8 and hematopoietic cell atypia that was suggestive but not diagnostic of MDS. Signals that corresponded to trisomy 8 were detected in 14.6% to 32.2% of the cells (detection threshold of trisomic clone, 5.0%). The conditions of two patients have remained hematologically stable with no disease progression, and these two patients are now considered to have refractory anemia. The conditions of the other two patients rapidly progressed to morphologically recognizable MDSs. This study demonstrates that the detection of trisomy 8 by fluorescence in situ hybridization can provide useful supplemental information in bone marrow specimens with morphologic changes that are suggestive of but not sufficient for a diagnosis of MDS. It should prove to be useful when standard cytogenetic analysis has not been performed or when it is not readily available.