Pathologic and clinical features of primary pulmonary extranodal marginal zone B-cell lymphoma of MALT type

We reviewed pathologic, phenotypic, and clinical features of extranodal marginal zone lymphoma of mucosa-associated lymphoid tissue (MALT) type primarily involving lung to address unresolved questions regarding behavior and pathologic features of unambiguously diagnosed pulmonary MALT lymphoma. Lung specimens from 50 patients were reviewed. Forty-one had low-grade MALT lymphoma. Nine had low-grade MALT lymphoma and diffuse large B-cell lymphoma. The patients included 32 women and 18 men with a median age of 68 years (range 34-88 years). Half of the patients were asymptomatic at the time lymphoma was diagnosed. Radiographic abnormalities were more commonly unilateral (37 patients) than bilateral (12 patients). Localized masses or nodules occurred in 39 patients. Associated autoimmune disorders (29%) and monoclonal gammopathies (43%) were common. Low-grade lymphomas formed intraparenchymal masses composed of centrocyte-like cells, plasmacytoid lymphocytes, and plasma cells that formed lymphoepithelial lesions and exhibited a lymphangitic growth pattern. Mediastinal lymph nodes were involved histologically in 44% of cases. Lymphoma-specific survival was 71.7% at 10 years, and overall survival was significantly worse than age-and gender-matched control patients. None of the following features predicted those patients who had an adverse outcome: systemic symptoms, presence of autoimmune disorders or paraproteinemia, anatomic distribution and number of pulmonary lesions, lymph node involvement, or presence of anthracycline-treated large B-cell lymphoma.

Common germinal-center B-cell origin of the malignant cells in two composite lymphomas, involving classical Hodgkin's disease and either follicular lymphoma or B-CLL

BACKGROUND

Classical Hodgkin's disease (HD) and B-cell non-Hodgkin lymphoma (NHL) occasionally occur in the same patient. Such composite lymphomas represent interesting models to study the pathogenesis of B-cell lymphomas and the relationship between HD and B-cell NHL.

MATERIALS AND METHODS

We analyzed two composite lymphomas (a combination of classical HD with follicular lymphoma [FL] and a combination of classical HD with B-cell chronic lymphocytic leukemia [B-CLL]) by micromanipulation of single cells from tissue sections and amplification of immunoglobulin V region genes for the clonal relationship of the tumor cells.

RESULTS

In both cases, clonally related variable (V) genes with both shared as well as distinct somatic mutations were obtained from the two lymphomas, showing that in each of the cases the distinct tumor cells were members of a common germinal center (GC) B-cell clone. FL cells from two different lymph nodes of patient 1 showed a similar mutation pattern, suggesting that infiltration of these lymph nodes by tumor cells was not restricted to a particular FL cell or subclone. In the FL, a single cell was identified with a mutation signature indicating that premalignant cells can persist in the tissue.

CONCLUSIONS

The cases presented here further underline the close relationship between HD and B-cell NHL and the role of the GC in lymphomagenesis. Whereas the latter was already suggested for FL and HD, the present study indicates that also in the B-CLL subset characterized by mutated Ig genes, important steps in malignant transformation happen in the GC, and that HRS cells can derive from CD5-positive B cells.

Immunoglobulin heavy-chain gene rearrangement studies by Southern blot using DNA extracted from formalin-fixed, paraffin-embedded tissue

BACKGROUND

In most clinical molecular diagnostics laboratories, Southern blots for gene rearrangement studies are not routinely performed on formalin-fixed, paraffin-embedded (FFPE) tissue samples. In this study, immunoglobulin heavy-chain gene rearrangements by Southern blot using DNA extracted from FFPE tissue samples were studied.

METHODS AND RESULTS

Eleven paired freshly frozen and FFPE tissue samples were evaluated for immunoglobulin gene rearrangements by PCR and Southern blot analyses. An additional 14 selected samples sent to our laboratory to rule out lymphoma, for which only FFPE tissue (no frozen tissue) was available and for which PCR was interpreted as negative, were evaluated by the same techniques. Southern blots generated from DNA extracted from FFPE tissues were qualitatively identical to those generated from DNA extracted from fresh or freshly frozen tissue and correlated well with the final diagnoses. Ten interpretable Southern blots were generated in the 14 cases in which no frozen tissue was available. Four of these ten blots were interpreted as positive for an immunoglobulin gene rearrangement. Although the number of samples analyzed is small, success with Southern blotting correlated with increased sample size and sample width (1.17 vs 0.49 cm(2); P <.024; 0.71 vs 0.43 cm; P <. 049, respectively).

CONCLUSION

DNA extracted from FFPE tissue samples using the simple, efficient, and nontoxic techniques described in this report can be used in many cases for Southern blotting for the detection of clonality by gene rearrangement studies.

Detection of t(2;5) in anaplastic large cell lymphoma: comparison of immunohistochemical studies, FISH, and RT-PCR in paraffin-embedded tissue

Anaplastic large cell lymphoma (ALCL) is associated with the t(2;5)(p23;q35) translocation involving the anaplastic lymphoma kinase gene (ALK) and the nucleophosmin gene (NPM), which result in expression of a novel fusion protein, NPM-ALK (p80). Clinicopathologic studies have shown that ALK expression in ALCL is associated with improved 5-year survival rates when compared with ALCL lacking ALK expression. This study used paraffin-embedded tissue to compare interphase fluorescence in situ hybridization (FISH) and reverse transcriptase-polymerase chain reaction (RT-PCR) for the detection of t(2;5) with immunohistochemical analysis for the detection of ALK protein expression in 27 patients with CD30-positive ALCLs. ALK protein expression was detected with ALK1 antibody in 14 of the 27 patients. The neoplastic cells in 13 of these 14 lymphomas reacted with the p80NPM/ALK antibody. FISH, using a two-color ALK DNA probe, correlated 100% with the immunohistochemical results: a translocation involving the ALK gene was detected in all 14 lymphomas that reacted with anti-ALK1. RT-PCR, performed on 21 lymphomas, detected NPM-ALK mRNA in five of the lymphomas, all of which reacted with anti-ALK1 and showed ALK gene rearrangement by FISH. Lymphomas showing ALK1 reactivity occurred in a younger patient population (median age, 19.5 years) and were associated with improved 5-year survival rates (84%), as compared with lymphomas lacking ALK1 reactivity (median age, 68.0 years; 5-year survival rate, 35%; p = 0.008). We conclude that immunohistochemical studies, using antibody ALK1. and FISH for ALK gene rearrangement are equally effective for identifying patients with ALCL who have a favorable clinical outcome.

Identification of common germinal-center B-cell precursors in two patients with both Hodgkin's disease and non-Hodgkin's lymphoma

BACKGROUND

Hodgkin's disease and non-Hodgkin's B-cell lymphoma occasionally occur in the same patient. The identification of a common precursor of the two types of lymphoma would show definitively that Reed-Sternberg cells originate from B cells.

METHODS

We studied lymphomas from two patients, one with a composite lymphoma (classic Hodgkin's disease and a follicular lymphoma in the same lymph node) and the other with a T-cell-rich B-cell lymphoma that was followed by classic Hodgkin's disease. Single Reed-Sternberg cells and non-Hodgkin's lymphoma cells from frozen sections were micromanipulated. The rearranged immunoglobulin variable-region genes (V genes) of the heavy and light chains were amplified by the polymerase chain reaction from genomic DNA and sequenced.

RESULTS

In both patients, the Reed-Sternberg cells were related clonally to the non-Hodgkin's lymphoma B cells. The V genes carried somatic mutations (a hallmark of germinal-center B cells and their descendants). In both patients, some somatic mutations were shared by the Reed-Sternberg and non-Hodgkin's lymphoma cells, whereas other somatic mutations were found exclusively in one or the other cell type.

CONCLUSIONS

In two patients with classic Hodgkin's disease and non-Hodgkin's B-cell lymphoma, we identified a common B-cell precursor, probably a germinal-center B-cell, for both lymphomas. This finding suggests that the two types of lymphoma underwent both shared and distinct transforming events and provides proof of the B-cell derivation of Reed-Sternberg cells in classic Hodgkin's disease.

Molecular analysis of single B cells from T-cell-rich B-cell lymphoma shows the derivation of the tumor cells from mutating germinal center B cells and exemplifies means by which immunoglobulin genes are modified in germinal center B cells

T-cell-rich B-cell lymphoma (TCRBCL) belongs to the group of diffuse large cell lymphomas (DLL). It is characterized by a small number of tumor B cells among a major population of nonmalignant polyclonal T cells. To identify the developmental stage of the tumor progenitor cells, we micromanipulated the putative neoplastic large CD20(+) cells from TCRBCLs and amplified and sequenced immunoglobulin (Ig) V gene rearrangements from individual cells. In six cases, clonal Ig heavy, as well as light chain, gene rearrangements were amplified from the isolated B cells. All six cases harbored somatically mutated V gene rearrangements with an average mutation frequency of 15.5% for heavy (VH) and 5.9% for light (VL) chains and intraclonal diversity based on somatic mutation. These findings identify germinal center (GC) B cells as the precursors of the transformed B cells in TCRBCL. The study also exemplifies various means how Ig gene rearrangements can be modified by GC B cells or their malignant counterparts in TCRBCL: In one case, the tumor precursor may have switched from kappa to lambda light chain expression after acquiring a crippling mutation within the initially functional kappa light chain gene. In another case, the tumor cells harbor two in-frame VH gene rearrangements, one of which was rendered nonfunctional by somatic mutation. Either the tumor cell precursor entered the GC with two potentially functional in-frame rearrangements or the second VHDHJH rearrangement occurred in the GC after the initial in-frame rearrangement was inactivated by somatic mutation. Finally, in each of the six cases, at least one cell contained two (or more) copies of a clonal Ig gene rearrangement with sequence variations between these copies. The presence of sequence variants for V region genes within single B cells has so far not been observed in any other normal or transformed B lymphocyte. Fluorescence in situ hybridization (FISH) points to a generalized polyploidy of the tumor cells.

Osseous Hodgkin disease

BACKGROUND

Hodgkin disease rarely presents as an osseous lesion, and the majority of patients are found at staging to have concurrent disease in lymph nodes. Many cases of osseous Hodgkin disease have been misdiagnosed on initial biopsy.

METHODS

All cases of Hodgkin disease diagnosed by open bone biopsy at the Mayo Clinic were identified. These included patients with primary osseous tumors, those presenting with multiple sites of involvement (with osseous lesions), and those with recurrence in bone. Recut sections were subjected to immunohistochemical stains to confirm the diagnosis. Clinical data and follow-up information were obtained from patients' charts.

RESULTS

Twenty-five patients (15 males and 10 females with an average age of 37 years) with osseous Hodgkin disease were identified during the years 1927-1996. Three patients had solitary, osseous tumors and two had primary, multifocal, osseous Hodgkin disease without involvement of nonosseous sites. Twelve patients who presented with lesions in osseous sites also had nonosseous tumors detected at staging, and 8 patients had recurrent Hodgkin disease that presented in bone. The majority of patients with primary and recurrent tumors presented only with bone pain; >50% of patients with concurrent osseous and nonosseous disease also had B-type symptoms. Nearly all lesions were in the axial and proximal appendicular skeleton. Radiographic features included osteosclerotic, osteolytic, and mixed lytic/sclerotic patterns. Cortical destruction, periosteal new bone formation, and soft tissue masses were present in 50% of cases. The histologic diagnosis of osseous Hodgkin disease occasionally was problematic; osteomyelitis was the most frequent misdiagnosis. Immunohistochemical stains revealed expression of CD15 and CD30 in neoplastic cells (which were negative for CD45 and B-cell and T-cell antigens) in all but two cases. Involved lymph nodes typically exhibited nodular sclerosis Hodgkin disease. Three patients with primary solitary osseous Hodgkin disease received radiation treatment only; at last follow-up 2 patients were alive at 22 months and 10 years, respectively. Patients with concurrent osseous and nonosseous tumors exhibited a 60% overall survival rate, but at last follow-up all 4 patients diagnosed after 1986 still were alive; those with Hodgkin disease that recurred as osseous lesions had a 60% survival rate at 8 years, but only 1 of the 5 patients diagnosed since 1984 had died of disease.

CONCLUSIONS

Osseous Hodgkin disease typically presents with bone pain, and the majority of patients have concurrent nonosseous lesions detected at staging. Radiographic features of osseous Hodgkin disease vary but indicate an aggressive malignant process. The histologic diagnosis may be problematic; immunohistochemical stains aid in establishing the diagnosis of Hodgkin disease in bone. Survival of patients with osseous Hodgkin disease has been found to be good for the last 10 years.

Osseous Hodgkin disease

BACKGROUND

Hodgkin disease rarely presents as an osseous lesion, and the majority of patients are found at staging to have concurrent disease in lymph nodes. Many cases of osseous Hodgkin disease have been misdiagnosed on initial biopsy.

METHODS

All cases of Hodgkin disease diagnosed by open bone biopsy at the Mayo Clinic were identified. These included patients with primary osseous tumors, those presenting with multiple sites of involvement (with osseous lesions), and those with recurrence in bone. Recut sections were subjected to immunohistochemical stains to confirm the diagnosis. Clinical data and follow-up information were obtained from patients' charts.

RESULTS

Twenty-five patients (15 males and 10 females with an average age of 37 years) with osseous Hodgkin disease were identified during the years 1927-1996. Three patients had solitary, osseous tumors and two had primary, multifocal, osseous Hodgkin disease without involvement of nonosseous sites. Twelve patients who presented with lesions in osseous sites also had nonosseous tumors detected at staging, and 8 patients had recurrent Hodgkin disease that presented in bone. The majority of patients with primary and recurrent tumors presented only with bone pain; >50% of patients with concurrent osseous and nonosseous disease also had B-type symptoms. Nearly all lesions were in the axial and proximal appendicular skeleton. Radiographic features included osteosclerotic, osteolytic, and mixed lytic/sclerotic patterns. Cortical destruction, periosteal new bone formation, and soft tissue masses were present in 50% of cases. The histologic diagnosis of osseous Hodgkin disease occasionally was problematic; osteomyelitis was the most frequent misdiagnosis. Immunohistochemical stains revealed expression of CD15 and CD30 in neoplastic cells (which were negative for CD45 and B-cell and T-cell antigens) in all but two cases. Involved lymph nodes typically exhibited nodular sclerosis Hodgkin disease. Three patients with primary solitary osseous Hodgkin disease received radiation treatment only; at last follow-up 2 patients were alive at 22 months and 10 years, respectively. Patients with concurrent osseous and nonosseous tumors exhibited a 60% overall survival rate, but at last follow-up all 4 patients diagnosed after 1986 still were alive; those with Hodgkin disease that recurred as osseous lesions had a 60% survival rate at 8 years, but only 1 of the 5 patients diagnosed since 1984 had died of disease.

CONCLUSIONS

Osseous Hodgkin disease typically presents with bone pain, and the majority of patients have concurrent nonosseous lesions detected at staging. Radiographic features of osseous Hodgkin disease vary but indicate an aggressive malignant process. The histologic diagnosis may be problematic; immunohistochemical stains aid in establishing the diagnosis of Hodgkin disease in bone. Survival of patients with osseous Hodgkin disease has been found to be good for the last 10 years.

Laparoscopic biopsy for suspected abdominal lymphoma

This study retrospectively reviewed the findings in laparoscopic biopsy specimens from 51 consecutive patients with suspected abdominal lymphoproliferative disorders. Histologic evaluation was supplemented (as necessary) by paraffin-section or frozen-section immunohistochemical analysis or by Southern blot hybridization. The laparoscopic procedure was diagnostic of a lymphoproliferative disorder in 24 patients (47%), of other neoplasms in 5 patients (10%), and of reactive tissue in 11 patients (22%); no tissue could be obtained for technical reasons (adhesions and inaccessible lesions) in 11 patients (22%). The 24 patients with lymphoproliferative disorders diagnosed by laparoscopic techniques included 14 patients with a new diagnosis of lymphoma and 10 patients with recurrent disease; pathologic findings were diagnostic of diffuse large cell lymphoma (11 patients), follicular lymphoma (11 patients), chronic lymphocytic leukemia (1 patient), and lymphocyte-predominant Hodgkin's disease (1 patient). Previous abdominal cytologic or core-needle biopsy specimens from 11 lymphoma patients did not yield an unequivocal diagnosis or subtype of lymphoma. The 11 patients (22%) in whom laparoscopic techniques did not produce a tissue sample needed laparotomy (10 patients) or femoral lymph node biopsy (1 patient) to document the diagnosis of large cell lymphoma (2 patients), follicular lymphoma (5 patients), composite lymphoma (1 patient), myeloma (1 patient), neurofibroma (1 patient), and reactive lymph nodes (1 patient). In the majority of patients with suspected abdominal lymphoma, laparoscopic techniques provide sufficient tissue for the diagnosis and classification of lymphoma and for the diagnosis of other causes of abdominal lymphadenopathy.

Epstein-Barr virus-induced T cell lymphoma in solid organ transplant recipients

Epstein-Barr virus (EBV) infection in transplant recipients can lead to lymphomas termed posttransplantation lymphoproliferative disorders (PTLDs). Most PTLDs are malignancies of B lymphocytes and are linked to EBV infection, but the rare T lymphocyte PTLDs have been inconsistently linked to EBV infection. Although the B lymphocyte is the main host cell of EBV, it has been suggested that T lymphocytes may also become infected by EBV. A review of EBV-induced PTLDs at our institution identified one of 61 cases that was restricted to T lymphocytes. Of 36 cases of T cell PTLD identified through a literature review, 21 were investigated for the presence of EBV, and eight (38%) were documented to be EBV-induced. We compared the features of EBV-positive and EBV-negative T cell PTLDs and concluded that cases of EBV-positive T cell PTLD have some distinctive clinical features.

Primary laryngeal lymphoma

Primary laryngeal lymphoma is a very rare entity, with fewer than 50 cases reported in the English literature in the past 60 years. Close scrutiny of some of these case reports reveals that the larynx was not always the only site of involvement, thereby diminishing the total number of patients with primary laryngeal lymphoma to fewer than 35. The authors report a series of six patients, who were seen and evaluated at the Mayo Clinic between 1952 and 1995, with stage IAE non-Hodgkin's lymphoma of the larynx. Three patients had large-cell lymphomas according to the REAL (Revised European-American Lymphoid) classification. The other three had a small lymphocytic lymphoma, follicular small cleaved lymphoma, and follicular mixed lymphoma. All patients received radiation therapy alone as initial therapy for their disease and all patients had a complete remission to initial therapy. Four patients subsequently relapsed and the histology at relapse was the same as the initial histology in all four patients. Five patients have died, three of lymphoma, with a median survival of 67 months (range, 40 to 228 months). In view of the heterogeneity of histologies in this group of lymphomas, the variability in duration of response, and the significant number of patients who died of their disease, it is more likely that primary laryngeal lymphoma is an unusual presentation of non-Hodgkin's lymphoma than a separate disease entity. Despite the small number of patients in this study, the data would suggest that patients are best treated according to the histology of the lymphoma, rather than the limited stage and location of the disease.

Follicular dendritic cell sarcoma mimicking diffuse large cell lymphoma: a case report

Follicular dendritic cell sarcomas (FDCSs) are rare tumors arising from follicular dendritic cells in lymphoid tissue. Fewer than 20 cases have been described in the English-language literature. We describe the second case of an FDCS with primary liver involvement. The initial diagnosis was lymphoma, and appropriate treatment was prescribed. After the initial treatment failed, additional biopsy samples were obtained. Standard pathologic analysis and immunophenotyping for a panel of monoclonal antibodies were performed on formalin-fixed paraffin-embedded tissue and frozen sections. The pathologic findings were consistent with FDCS, and the specimens showed some of the characteristic pathologic features suggestive of this tumor, including multinucleation and a spindle pleomorphic morphology. The tumor cells were positive for S-100 protein, CD45, CD14, and vimentin. Because of its morphological characteristics, FDCS can be confused with other neoplastic entities, such as lymphomas and other solid tumors.

Adrenal insufficiency as a manifestation of disseminated non-Hodgkin's lymphoma

OBJECTIVE

To analyze the clinical characteristics, laboratory features, and outcome in five patients who had biochemically proven adrenal insufficiency attributable to pathologically confirmed non-Hodgkin's lymphoma (NHL).

MATERIAL AND METHODS

We retrospectively reviewed the medical records of all patients at Mayo Clinic Rochester during the period from 1976 to 1994 to identify those with both NHL, as listed in the surgical pathology tissue registry, and adrenal insufficiency. Histologically, the patients were classified on the basis of the working formulation and the revised European-American lymphoma classification.

RESULTS

Three patients had diffuse large cell NHL, one patient had small noncleaved NHL, and one patient had cutaneous T-cell NHL. All five patients had stage IV disease. Adrenal insufficiency was confirmed by morning and evening determinations of serum cortisol levels and cosyntropin stimulation tests. All patients demonstrated loss of circadian rhythm. The median age of the patients was 77 years (range, 60 to 89). Three of the five patients died without treatment from 5 to 22 days after assessment. One patient died of a cerebrovascular accident. Despite initiation of chemotherapy, two patients died of progressive NHL at 7 weeks and 7 months.

CONCLUSION

In our experience, biochemically proven adrenal insufficiency in patients with NHL is a manifestation of clinically advanced disease in elderly patients. A stepwise diagnostic approach is critical for the appropriate management of such patients.

Hodgkin and Reed-Sternberg cells in lymphocyte predominant Hodgkin disease represent clonal populations of germinal center-derived tumor B cells

Among the four subtypes of Hodgkin disease (HD), lymphocyte-predominant (LP) HD is now generally considered as a separate entity. The B cell nature of the typical Hodgkin and Reed-Sternberg (HRS) cells and their variants (L and H, lymphocytic and histiocytic cells) in LP HD has long been suspected, but the question of whether these cells represent a true tumor clone is unclear. We previously demonstrated clonal Ig gene rearrangements in one case of LP HD. In the present study, five cases of LP HD were analyzed by micromanipulation of single HRS cells from frozen tissue sections and DNA amplification of rearranged Ig heavy chain genes from those cells. Clonal V gene rearrangements harboring somatic mutations were detected in each case. In three cases ongoing somatic mutation was evident. This shows that HRS cells in LP HD are a clonal tumor population derived from germinal center B cells. The pattern of somatic mutation indicates that HRS cells in LP HD are selected for antibody expression. This, and the presence of ongoing mutation discriminates LP from classical HD.

Follicular dendritic cell sarcoma mimicking diffuse large cell lymphoma: a case report

Follicular dendritic cell sarcomas (FDCSs) are rare tumors arising from follicular dendritic cells in lymphoid tissue. Fewer than 20 cases have been described in the English-language literature. We describe the second case of an FDCS with primary liver involvement. The initial diagnosis was lymphoma, and appropriate treatment was prescribed. After the initial treatment failed, additional biopsy samples were obtained. Standard pathologic analysis and immunophenotyping for a panel of monoclonal antibodies were performed on formalin-fixed paraffin-embedded tissue and frozen sections. The pathologic findings were consistent with FDCS, and the specimens showed some of the characteristic pathologic features suggestive of this tumor, including multinucleation and a spindle pleomorphic morphology. The tumor cells were positive for S-100 protein, CD45, CD14, and vimentin. Because of its morphological characteristics, FDCS can be confused with other neoplastic entities, such as lymphomas and other solid tumors.

Splenic vascular tumors: a histologic, immunophenotypic, and virologic study

Vascular tumors of the spleen include several different entities, some of which are unique to that organ. Twenty-two such proliferations were studied, including 10 hemangiomas, six littoral cell angiomas, four angiosarcomas, and two hamartomas. The hemangiomas included seven with localized tumors and three with diffuse angiomatosis of the spleen. All cases were studied by paraffin section immunohistochemistry with a large panel of antibodies. In addition, all cases were studied for the presence of the Kaposi's sarcoma-associated herpesvirus (KSHV) using the polymerase chain reaction. The morphologic findings were similar to those previously reported. All proliferations were vimentin positive, and one angiosarcoma was focally keratin positive. All cases reacted for CD31, whereas 20 of 22 were positive for von Willebrand's factor and 19 of 22 were positive for Ulex europeaus. CD34 expression in lining cells was identified in 10 of 10 hemangiomas, two of four angiosarcomas, and one of two hamartomas, whereas all six cases of littoral cell angioma were negative. CD68 was expressed in all cases of littoral cell angioma but was also positive in all three diffuse hemangiomas, two of seven localized hemangiomas, and two of four angiosarcomas. CD21 expression was restricted to the lining cells of littoral cell angioma, and CD8 expression was only identified in two of two hamartomas and two of four angiosarcomas. KSHV was not detected in any of the cases. These findings suggest that there are distinct immunophenotypic as well as morphologic features of splenic vascular tumors. Littoral cell angiomas have a characteristic CD34-/CD68+/CD21+/CD8- immunophenotype and hamartomas have a characteristic CD68-/CD21-/CD8+ phenotype. The frequent CD68 expression in diffuse hemangioma suggests an immunophenotypic difference from localized hemangioma of the spleen.

Splenic mesothelial cysts mimicking lymphagiomas

Lymphangiomas of the spleen may occur as part of lymphangiomatosis or may represent solitary lesions. Solitary splenic lymphangiomas are described traditionally as subcapsular, multicystic proliferations that are often incidental findings. Six cases of splenic tumors with morphologic features similar to those described for solitary lymphangioma were studied using an immunohistochemical panel that included epithelial and vascular markers. None of the patients had evidence of lymphangiomatosis, and all tumors were incidental findings in splenectomy specimens. All cases demonstrated lining cells that were positive for keratin and the mesothelial cell-associated antibody HBME-1 but were negative for the vascular markers Factor VIII-related antigens, CD31, and CD34. The immunohistochemical findings are suggestive of a mesothelial derivation of these multicystic proliferations rather than representing true lymphangiomas.

Development of monoclonal gammopathy precedes the development of Epstein-Barr virus-induced posttransplant lymphoproliferative disorder

Epstein-Barr virus (EBV)-induced posttransplant lymphoproliferative disorder (PTLD) develops in 3% to 10% of solid organ transplant recipients with a resultant mortality of up to 70%. Unfortunately, there is no current marker which identifies patients who will develop this disease. We therefore conducted a risk factor analysis of variables that might predict the development of PTLD. Specifically, since EBV may cause both PTLD and the development of monoclonal proteins (M protein), we sought to determine if the development of an M protein preceded and therefore might serve as a predictive marker of subsequent PTLD. Before and after liver transplantation, 201 patients were evaluated for the presence of urine and serum M proteins. Patients were followed to monitor the development of PTLD for a mean of 1,733 days. PTLD developed in seven patients (3.5%), three (43%) of whom died from disseminated PTLD. PTLD was classified as polymorphous in six patients and monomorphous in one patient. Fifty-seven patients (28%) developed an M protein after transplantation: five of seven patients (71%) with PTLD and 52/194 (27%) of patients without PTLD. Multivariate risk factor analysis for the development of an M protein after transplantation identified cytomegalovirus (CMV) donor seropositivity (P = 0.0002) and postoperative symptomatic CMV infection (P = 0.019) as risk factors. Whereas EBV serostatus of either the donor or recipient was not found to be a risk factor for the occurrence of either an M protein or PTLD, the development of a serum immunoglobulin M (IgM) M protein (P = 0.04) and of any urine M protein (P = 0.01) was identified by univariate analysis as being associated with the development of PTLD. Further studies are needed to determine the predictive value of M proteins as a marker for PTLD. Until such time, the development of serum or urine M protein should heighten the suspicion of developing PTLD.

Lymphoma in soft tissue: a clinicopathologic study of 19 cases

The authors retrospectively reviewed 19 patients who presented with lymphoma as soft tissue masses, without evidence of lymph node or skin involvement. Sites of involvement included lower extremity (seven), upper extremity (six), chest wall (three), gluteal region (two), and frontal subgaleal region (one). Histological and immunophenotypic studies revealed 12 large cell lymphomas (11 B cell and one T cell), two small noncleaved cell lymphomas (B-cell phenotype), and five low grade B-cell lymphomas (two small lymphocytic and three follicular mixed lymphomas). Patients with large cell lymphoma, including seven patients with stages I and II and five patients with stage IV, were treated with anthracycline-based chemotherapy, with or without radiation therapy. One half of these patients are dead of disease, including four of seven with low stage disease. The two patients with small noncleaved cell lymphoma had stage IE disease and were treated with chemotherapy; one died at 11 months, and the other is alive and disease free at 65 months. Patients with low grade B-cell lymphoma included four stage IE patients who were treated with radiation and one stage IV patient treated with chemotherapy. Two patients are alive and disease free, and three are dead of unrelated causes. The authors conclude that malignant lymphomas initially diagnosed in soft tissues are most commonly large cell lymphomas with a B-cell phenotype.

Nasal and nasopharyngeal angiocentric T-cell lymphomas

Thirty patients (24 mean and 6 women) with a median age of 44.5 years who had angiocentric T-cell lymphoma were studied. The neoplastic cells in each had a T-cell phenotype. Epstein-Barr virus RNA was detected in the neoplastic cells in 29 of 30 patients. The most common presenting symptom was nasal obstruction followed by purulent rhinorrhea. Patients with early presentation had only a friable nasal or nasopharyngeal mucosa; late clinical signs included septal perforation in 40%. Twenty-one of 30 patients received radiation therapy as initial treatment; 22 of 30 patients achieved a complete remission. Fifteen patients relapsed: 10 with local recurrence and 5 with systemic disease. In long-term follow-up, 10 patients were alive and disease free, 6 patients died of unrelated causes, and 12 patients died of disease.

Lymphomatoid granulomatosis. Evidence of immunophenotypic diversity and relationship to Epstein-Barr virus infection

We studied open-lung biopsies from 17 patients with pulmonary lymphomatoid granulomatosis (LYG) using paraffin-section immunostains and Epstein-Barr virus (EBV) RNA in situ hybridization to assess the phenotype of these unique tumors and to clarify the role of EBV infection. Histologically, all cases demonstrated the characteristic mixed mononuclear cell infiltrate of lymphomatoid granulomatosis with variable numbers of cytologically atypical large lymphoid cells in a background of small lymphocytes. Paraffin-section immunostains in all cases showed a predominance of T lymphocytes. A minor population of CD20-positive large B lymphocytes was identified in 11 cases; immunoglobulin light-chain restriction was demonstrated in four of these and immunoglobulin gene rearrangements in another case. Nuclear labelling for EBV RNA was detected in 10 of these 11 cases and was confined to the population of large B lymphocytes. Staining for CD20 was absent in the remaining six cases, as was nuclear labeling for EBV RNA. However, the large atypical lymphoid cells stained for T-cell-lineage-specific antibodies in three of these cases. We conclude that some cases of lymphomatoid granulomatosis are B-cell lymphoma associated with EBV infection, whereas others are of T-cell origin and are probably unrelated to EBV infection.

Somatic mitochondrial mutation in gastric cancer

Likely hot spots for mutations are mitochondrial sequences as there is less repair and more damage by carcinogens compared with nuclear sequences. A somatic 50-bp mitochondrial D-loop deletion was detected in four gastric adenocarcinomas. The deletion included the CSB2 region and was flanked by 9-bp direct repeats. The deletion was more frequent in adenocarcinomas arising from the gastroesophageal junction (4/32, 12.5%) compared with more distal tumors (0/45). Topographical analysis revealed the absence of the deletion from normal tissues except in focal portions of smooth muscle in one case. In two cases, apparent mutant homoplasmy was present throughout two tumors, including their metastases. In the two other cases, the mutation was present in only minor focal portions ( < 5%) of their primary tumors. These findings document the presence of somatic mitochondrial alterations in gastric cancer, which may reflect the environmental and genetic influences operative during tumor progression.

Pretransplantation assessment of the risk of lymphoproliferative disorder

Posttransplantation lymphoproliferative disorder (PTLD) is an uncommon but often fatal complication of solid organ transplantation that occurs in approximately 3% of patients. To determine the relative importance and relationship of potential risk factors for PTLD before transplantation (i.e., Epstein-Barr virus [EBV] serostatus of the recipient and the cytomegalovirus [CMV] sero-status of the recipient and the potential donor) and the principal risk factor after transplantation (immunosuppression with antilymphocyte antibody), we analyzed the findings for the first 381 consecutive adult nonrenal transplant recipients seen at Mayo Clinic. In the absence of the other risk factors, the incidence rate of PTLD for EBV-seronegative recipients was 24 times higher (95% confidence interval [CI]: 6.2, 89) than that for EBV-seropositive recipients. The additional risk factors of therapy with OKT3 for rejection and CMV seromismatch (i.e., a negative recipient and a positive donor) each further amplified this risk four- to sixfold. Together, all three risk factors acted synergistically to increase the incidence rate of fatal and/or CNS PTLD by a factor of 654 (CI: 368, 1,162) compared with the low incidence rate (.458 cases per 100 person years) when none of these risk factors were present. Pretransplantation determination of recipient EBV and CMV serostatus can identify a subgroup of patients whose risk for severe PTLD may preclude transplantation.

Pretransplantation seronegative Epstein-Barr virus status is the primary risk factor for posttransplantation lymphoproliferative disorder in adult heart, lung, and other solid organ transplantations

BACKGROUND

The relative importance and interrelationship of risk factors for posttransplantation lymphoproliferative disorder are poorly understood.

METHODS

The prospective pretransplantation serologic testing for Epstein-Barr virus of all nonrenal solid organ transplant recipients at our institution made it possible to assess the relative risk for posttransplantation lymphoproliferative disorder in seropositive and seronegative recipients.

RESULTS

Fourteen cases of lymphoproliferative disorder were identified in the first 389 consecutive transplant recipients (288 liver, 44 heart, 20 lung, 37 kidney-pancreas) undergoing transplantation from 1985 to 1992 (mean follow-up 33 months). The incidence rates of lymphoproliferative disorder (per 100 person-years) during the first 2 years after transplantation (a period in which all cases occurred) were 1.4 for liver, 2.0 for heart, 6.2 for lung, and 5.2 for kidney-pancreas transplant recipients and were significantly different between liver and lung (p = 0.005) and liver and kidney-pancreas (p = 0.002) groups. Of 367 seropositive patients, lymphoproliferative disorder developed in only three. The incidence rate ratios between seronegative and seropositive recipients were as follows: 76 ([95% confidence interval; 46, 144], p = 0.0000) for any form of lymphoproliferative disorder and 145 ([60, 347], p = 0.0000) for fatal or brain forms. The incidence rate of lymphoproliferative disorder was significantly higher for seronegative recipients who required antilymphocyte antibody therapy for rejection than for those who received none.

CONCLUSIONS

The high intrinsic risk for lymphoproliferative disorder in the Epstein-Barr virus seronegative patient, which is amplified by higher levels of immunosuppression, may, in some instances, preclude transplantation.

Management of stage IE primary gastric lymphoma

From 1975 to 1991, stage IE gastric lymphoma was diagnosed or treated in 40 patients at our institution. Thirty-five evaluable patients were the subject of this analysis (median age, 63 years). All histologic specimens were reviewed and classified according to the working formulation. Immunohistochemical stains were performed in 33 of 35 cases. The following histologic subtypes were identified: 26 patients had diffuse large cell, 2 had diffuse mixed cell, and 7 had mucosa-associated lymphocytic lymphoma (small lymphocytic lymphoma with features of MALT lymphoma). Of the 35 patients, 30 (86%) underwent laparotomy, with subtotal or total gastrectomy performed in 29. After gastrectomy, 17 patients had radiation therapy, 3 had chemotherapy, 2 had radiation plus chemotherapy, and 7 had no further treatment. Five patients were diagnosed with endoscopic biopsy and had radiation therapy, chemotherapy, or both without further surgical treatment. The median follow-up period was 69.2 months. The commonest presenting symptom was pain. The 5-year disease-free survival was 90% for the entire group and 88% for the 28 patients with working formulation intermediate histology. For patients with MALT lymphoma, the 5-year disease-free survival was 100%. The prognosis for patients with stage IE working formulation intermediate-histology gastric lymphoma is good and for those with stage IE MALT lymphoma, excellent.

p53 mutations and microsatellite instability in sporadic gastric cancer: when guardians fail

Genetic instability may underlie the etiology of multistep gastric carcinogenesis. The altered microsatellites observed in tumors with the ubiquitous somatic mutation (USM) phenotype may represent the expression of such instability. Similarly, p53 mutations may allow the accumulation of genetic alterations caused by multiple mechanisms. In 40 sporadic gastric adenocarcinomas, nine tumors (22.5%) with p53 mutations in exons 5-8, and six tumors (15%) with the USM+ phenotype, were detected. None of the tumors had both alterations. The tumors with p53 mutations were predominantly in the proximal stomach whereas the USM+ tumors were predominantly in the distal stomach. The mutant p53 alleles were homogeneously distributed throughout the primary tumors, but usually absent from adjacent normal or dysplastic epithelium, indicating that p53 mutations are typically acquired before the bulk of clonal expansion. The loss of mutant p53 alleles during progression was also rarely observed in metastatic foci. Altered microsatellites were homogeneously present in the USM+ primary and metastatic tumors and one synchronous tubular adenoma, but were not detected in adjacent normal and metaplastic epithelium. These findings also demonstrate that the USM+ phenotype is expressed before the bulk of clonal expansion. In most (5 of 6) USM+ tumors, the sizes of the altered microsatellites differed between regions, indicating that the instability usually persists during clonal expansion. These findings indicate that both p53 mutations and the USM+ phenotype are present prior to the bulk of tumor growth and therefore may contribute to, rather than be a late consequence of, malignant transformation.

Pancreatic lymphoma: is it a surgical disease?

Primary pancreatic lymphoma is a rare neoplasm that reportedly regresses promptly with aggressive chemotherapy. Recently, the role of surgical management has been relegated to biopsy alone. The aim of this study was to review our experience with primary pancreatic lymphoma and to determine the outcome of patients managed by radiation therapy and/or chemotherapy. From 1952 to 1991, 107 patients with non-Hodgkin's lymphoma involving the pancreas were identified. Twelve patients (11%) had primary pancreatic lymphoma. The presenting symptoms and signs were nonspecific: abdominal pain (83%), weight loss (50%), and a palpable mass (58%). Six of the 12 patients (50%) undergoing celiotomy had a preoperative diagnosis of pancreatic carcinoma. These lymphomas were large (x = 8 +/- 2 cm) and deemed unresectable because of size, alleged mesenteric vessel encroachment, regional lymph node metastasis, or because of an intraoperative diagnosis of lymphoma. Biopsy alone was performed in 50% of patients and biliary bypass and/or gastroenterostomy was performed in 25% of patients. A single resection (pancreatoduodenectomy) was performed 1 year after a full course of chemotherapy had failed. Ten patients, all of whom died of progressive lymphoma, received primary postoperative radiation therapy and/or chemotherapy, and no patient was disease-free at follow-up. Mean survival was 13 months for patients who received chemotherapy alone (n = 2), 22 months for those treated with radiation therapy only (n = 5), and 26 months for those receiving combined radiation therapy and chemotherapy (n = 3).(ABSTRACT TRUNCATED AT 250 WORDS)

Pancreatic lymphoma: is it a surgical disease?

Primary pancreatic lymphoma is a rare neoplasm that reportedly regresses promptly with aggressive chemotherapy. Recently, the role of surgical management has been relegated to biopsy alone. The aim of this study was to review our experience with primary pancreatic lymphoma and to determine the outcome of patients managed by radiation therapy and/or chemotherapy. From 1952 to 1991, 107 patients with non-Hodgkin's lymphoma involving the pancreas were identified. Twelve patients (11%) had primary pancreatic lymphoma. The presenting symptoms and signs were nonspecific: abdominal pain (83%), weight loss (50%), and a palpable mass (58%). Six of the 12 patients (50%) undergoing celiotomy had a preoperative diagnosis of pancreatic carcinoma. These lymphomas were large (x = 8 +/- 2 cm) and deemed unresectable because of size, alleged mesenteric vessel encroachment, regional lymph node metastasis, or because of an intraoperative diagnosis of lymphoma. Biopsy alone was performed in 50% of patients and biliary bypass and/or gastroenterostomy was performed in 25% of patients. A single resection (pancreatoduodenectomy) was performed 1 year after a full course of chemotherapy had failed. Ten patients, all of whom died of progressive lymphoma, received primary postoperative radiation therapy and/or chemotherapy, and no patient was disease-free at follow-up. Mean survival was 13 months for patients who received chemotherapy alone (n = 2), 22 months for those treated with radiation therapy only (n = 5), and 26 months for those receiving combined radiation therapy and chemotherapy (n = 3).(ABSTRACT TRUNCATED AT 250 WORDS)

Polymorphic reticulosis: a reappraisal

We studied 18 patients (15 men and three women) evaluated for a destructive sinonasal lesion that had been diagnosed as "polymorphic reticulosis." The histologic features of each lesion were those of angiocentric immunoproliferative lesions," characterized by atypical lymphoid infiltrates with polymorphous, angiocentric, and necrotic features; 13 were grade 2 and five were grade 3. The neoplastic cells in each patient had a T-cell phenotype. Epstein-Barr virus RNA was detected in the neoplastic cells of 17 of the 18 T-cell lesions. Initial treatment consisted of local radiation therapy in each patient, chemotherapy in two patients, and prednisone in another patient. Two patients were lost to follow-up and the other 16 had a median follow-up of 14 years, 2 months (range, 4 months to 32 years, 5 months). Four patients are alive and disease free, four patients died not of disease or complication of therapy, and eight patients died of disease. The Kaplan-Meier estimate of survival was 63% at 5 years and 50% at 15 years. Histologic progression of angiocentric immunoproliferative lesions from grade 2 to grade 3 was observed in two patients, and a correlation between angiocentric immunoproliferative grade and survival could not be detected. These data suggest that polymorphic reticulosis is an Epstein-Barr virus-related angiocentric T-cell lymphoma.

Granuloma annulare in patients with malignant lymphoma: clinicopathologic study of thirteen new cases

BACKGROUND

Reports of necrobiotic granulomas or granuloma annulare in patients with malignant lymphoma are rare.

OBJECTIVE

Our intent was to determine any unique clinical or histopathologic features in patients with granuloma annulare and lymphoma.

METHODS

We reviewed the medical records and biopsy material from 13 patients with granuloma annulare and lymphoma.

RESULTS

Three patients had Hodgkin's disease and 10 had non-Hodgkin's lymphoma. The granuloma annulare lesions showed typical histopathologic features. However, the clinical pattern was frequently atypical, with painful lesions in unusual locations including the palms and soles. Three patients displayed granulomatous inflammation in noncutaneous sites, either within the malignant lymphoma or in uninvolved tissues, and all three had atypical clinical presentations of granuloma annulare.

CONCLUSION

Granuloma annulare with atypical clinical presentations may be associated with an underlying hematopoietic malignancy and may be part of a generalized granulomatous reaction to malignant lymphoma.

Herpes simplex infection causing acute necrotizing tonsillitis

OBJECTIVE

To describe the clinical and pathologic features of acute herpetic tonsillitis and to compare the histologic findings with those of herpetic lymphadenitis.

DESIGN

We present a case report of a 22-year-old woman with bilateral cervical adenopathy, acute tonsillitis, and suspected peritonsillar abscess.

MATERIAL AND METHODS

Histologic examination of the excised tonsils demonstrated discrete necrotic areas that contained cells with intranuclear viral inclusions.

RESULTS

The diagnosis of herpetic tonsillitis was confirmed by demonstrating herpes simplex virus (HSV)-infected cells on paraffin section immunostains and by positive HSV cultures of the tonsillar tissue.

CONCLUSION

HSV infection is an uncommon cause of acute tonsillitis; the histologic findings are similar to those seen in herpes simplex lymphadenitis.

Activation of c-erbB-2 and prognosis in ovarian carcinoma. Comparison with histologic type, grade, and stage

BACKGROUND

Prior reports suggested that measuring c-erbB-2 activation in ovarian carcinomas might be valuable in predicting prognosis. The authors attempted to confirm these studies while specifically excluding tumors of low malignant potential.

METHODS

The clinical and pathologic significance of c-erbB-2 oncogene activation was assessed in 56 ovarian carcinomas, none of which met histologic criteria for tumor of low malignant potential.

RESULTS

By using an immunohistochemical technique previously validated in molecular studies, c-erbB-2 oncogene overexpression was identified in 10 of the 56 carcinomas but did not correlate with histologic type, histologic grade, International Federation of Gynecology and Obstetrics (FIGO) stage, or prognosis. Adverse prognostic factors included histologic type (serous carcinoma), high grade, and high stage (FIGO Stages III and IV). Grade and stage were highly correlated with each other and were more important prognostic indicators than histologic type.

CONCLUSION

Measuring c-erbB-2 activation in ovarian carcinomas may not be of practical value in predicting prognosis when tumors of low malignant potential are excluded.

Treatment of stage IE primary lymphoma of bone

PURPOSE

A retrospective analysis was performed to assess the efficacy of various treatments of Stage IE primary non-Hodgkins lymphoma of bone.

METHODS AND MATERIALS

Sixty-three patients with Stage IE primary non-Hodgkins lymphoma of bone (single osseous focus) were seen at our institution between the years 1970 and 1989. Information was obtained regarding each patients' presentation and clinical course. The histology was reviewed in all patients. Modern immunohistochemical stains were performed on each case with available paraffin-embedded tissue.

RESULTS

The histologic classification of the tumors was as follows: 43 diffuse large cell, 13 diffuse mixed cell, 3 small noncleaved, and 4 unclassified. The most common presenting symptom was pain (97%) and the following bony sites were involved: 36 long bone, 9 flat bone, 13 spine, and 5 pelvis. Of the 63 cases, 50 were treated with radiation alone, 10 with chemotherapy and radiation, 2 with chemotherapy alone, and 1 with surgery alone. Univariate analysis revealed a suggestion of an improved 5-year disease-free survival for patients treated with chemotherapy and radiation vs. radiation alone (90% vs. 57% respectively, p = .08). Multivariate analysis (controlling for extent of initial evaluation, extent of pathological evaluation and other potential prognostic factors) showed that neither treatment resulted in superior outcome with respect to disease-free survival, disease specific survival, or overall survival, however, doses of radiation greater than 4000 cGy resulted in improved overall survival compared to lower doses (p = 0.01).

CONCLUSION

This study supports the use of primary RT (> 4000 cGy) for Stage IE PLB, however, the addition of chemotherapy to the radiotherapeutic management may decrease the initial relapse rate of some patients. Future studies should address this question.

Nasal T-cell lymphoma

Nasal T-cell lymphomas represent a controversial subset of malignant lymphomas and include lesions previously termed midline malignant reticulosis, lymphomatoid granulomatosis, and polymorphic reticulosis. Nasal T-cell lymphomas are rare in Western populations and much more prevalent in Asian countries. Clinically, adult males are most often affected. Histologically, an angiocentric infiltrate composed of a spectrum of atypical cells is usually present. Phenotypically, the neoplastic cells lack expression of B-lineage markers, and usually express the T-lineage-associated markers CD2, CD45RO, and CD43; however, they often lack other pan-T-lineage markers. They often express the natural killer marker CD56, but usually lack the natural killer markers CD16 and CD57. Gene rearrangement studies have shown a germline configuration for the antigen receptor genes in the majority of cases. To date, evidence of Epstein-Barr virus has been consistently demonstrated, regardless of the geographic region studied. In situ hybridization studies have localized the Epstein-Barr virus to the atypical cells.

Infectious mononucleosis in lymphoid tissue. Histopathology, in situ hybridization, and differential diagnosis

The histopathologic features of tissue specimens from 16 patients with acute Epstein-Barr virus-induced infectious mononucleosis, which was confirmed by clinical and serologic methods, are described. The clinical course was usually self-limited (14 patients), but it resulted in the death of two patients, one of whom (patient with renal transplantation) was immunosuppressed. Each lymphoid tissue specimen, including those obtained from the lymph nodes (n = 9), tonsils (n = 5), spleen (n = 1), and appendix (n = 1), showed a nonuniform expansion of nonfollicular areas by a polymorphous population of lymphocytes, including transformed lymphocytes and immunoblasts. In situ hybridization demonstrated Epstein-Barr virus-infected lymphocytes in four of eight tissue specimens that were studied. Other histologic features included Reed-Sternberg-like cells, plasma cells, histiocytes, frequent mitoses, abundance of postcapillary venules, and necrosis. These histologic features should suggest a diagnosis of infectious mononucleosis rather than other processes, either benign or malignant, that can mimic it.

Detection of Epstein-Barr virus by in situ hybridization with a commercially available biotinylated oligonucleotide probe

Epstein-Barr virus (EBV) nucleotide sequences can be detected in routinely processed tissues by in situ hybridization (ISH) with either radiolabeled or nonisotopic EBV probes. In this paper, we describe our nonisotopic ISH protocol for EBV detection with use of a triple-biotinylated oligonucleotide NotI/PstI EBV probe. We compared this technique with our radioisotopic ISH technique that uses a 35S-labeled EBV probe and found that the nonisotopic technique was as sensitive as the radioisotopic technique for detecting EBV-infected cells in tissues from patients with posttransplantation lymphoproliferative disorders. Furthermore, use of the biotinylated probe has several advantages over the 35S-labeled probe, including commercial availability of labeled probe, increased probe stability, decreased technical and development time, and ease of interpretation. We conclude that the nonisotopic ISH procedure is practical for use in diagnostic surgical pathology.

Combined histochemical stains in the differential diagnosis of Cryptococcus neoformans

Three combinations of histochemical stains were used to study 69 routinely processed tissues containing various "yeast-like" fungal organisms (Cryptococcus neoformans, Blastomyces dermatitidis, Coccidioides immitis, Histoplasma capsulatum, Paracoccidioides brasiliensis, and Candida albicans). Fontana-Masson stain combined either with mucicarmine or Alcian blue produced distinctive staining of C. neoformans (Fontana-Masson-positive wall and mucin-positive capsule) that was not identified in other fungi. The Alcian blue stain combined with periodic acid-Schiff reaction also was useful for fungal classification, because the Alcian blue component reacted with only C. neoformans (capsule) and B. dermatitidis (wall) and the periodic acid-Schiff reaction reacted with the cell wall and body of each fungus. We concluded that the combined histochemical stains used in conjunction with morphologic study of hematoxylin and eosin- and Gomori methenamine silver-stained sections are helpful in the differential diagnosis of yeast-like fungal organisms.

Tryptophan-induced lung disease: an immunophenotypic, immunofluorescent, and electron microscopic study

L-tryptophan (LT) has been implicated as a causal agent in the recently recognized eosinophilia-myalgia syndrome (EMS). Pulmonary complications occur in up to 60% of patients. Lung biopsies have shown chronic interstitial pneumonia, mild eosinophilia, vasculitis and perivasculitis, and hypertensive pulmonary arteriopathy. Open lung biopsies from two women who developed respiratory symptoms associated with LT EMS were studied with a panel of antibodies to lymphoid cells, by transmission electron microscopy and by direct immunofluorescence for immunoglobulin and complement. The majority of the cells infiltrating the interstitium and around vessels were T-cells, with a predominance of CD8+ cells. Numerous alveolar macrophages were also identified. Rare polyclonal B-cells were also present. Ultrastructural studies confirmed the presence of interstitial and perivascular lymphocytes as well as occasional eosinophils. The inflammatory cells were also present in vessel cells. Fibrointimal thickening was not observed in the sections studied ultrastructurally. Immunofluorescent staining for IgG, IgA, C3, C4, albumin, kappa, and lambda was negative. There was scattered staining for fibrinogen in alveolar spaces. The etiology of LT EMS is still under investigation, although a contaminant acting in conjunction with host factors is the favored hypothesis. The results of this study indicate that T cytotoxic/suppressor cells may be intimately involved in the pathogenesis of the lung injury.

Overexpression of the c-erbB-2 oncogene in sarcomas and small round-cell tumors of childhood. An immunohistochemical investigation

Amplification and overexpression of the c-erbB-2 oncogene have been associated with a poor prognosis in breast cancer. The present study evaluates c-erbB-2 protein over-production in sarcomas and in small round-cell tumors of childhood by applying an immunohistochemical technique to formalin-fixed, paraffin-embedded tissues. This technique had previously demonstrated high sensitivity for the detection of c-erbB-2 activation. One peripheral neuroepithelioma demonstrated equivocal immunoreactivity for c-erbB-2 protein. There was no evidence of c-erbB-2 protein overproduction in 11 angiosarcomas, 21 chondrosarcomas, 10 epithelioid sarcomas, 14 Ewing's sarcomas, 20 hepatoblastomas, nine leiomyosarcomas, 12 liposarcomas, 13 malignant fibrous histiocytomas, nine malignant lymphomas, 15 neuroblastomas/ganglioneuroblastomas, 16 neurofibrosarcomas, 10 osteosarcomas, seven peripheral neuroepitheliomas, 10 rhabdomyosarcomas, six synovial sarcomas, and 20 Wilm's tumors. We conclude that overproduction of the c-erbB-2 protein is rare or absent in these neoplasms and that its detection is therefore not likely to be of practical utility in their pathologic evaluation and prognostication.

Detection of c-erbB-2 activation in paraffin-embedded tissue by immunohistochemistry

Commercially available monoclonal antibodies were tested for their ability to detect increased levels of c-erbB-2 protein in formalin-fixed, paraffin-embedded breast carcinomas. Of five antibodies studied, four (TAB-250, CB11, 3B5, and N3/D10) showed strong cytoplasmic membrane reactivity in 23% (11 of 47) of routinely processed tumors, although interpretation of the immunoreactivity with 3B5 and N3/D10 occasionally was difficult due to cytoplasmic granular staining. Since the c-erbB-2 oncogene is activated by DNA amplification and overexpression of mRNA and protein, the same tumors were analyzed for c-erbB-2 activation by other techniques. c-erbB-2 activation in these 11 tumors was confirmed by immunohistochemistry of frozen tissue (nine of nine tumors), in situ hybridization (nine of 11 tumors), and Southern blot analysis (five of eight tumors). In some of these tumors the failure to demonstrate c-erbB-2 DNA amplification may be due to the small percentage of malignant cells. One additional tumor showed probable c-erbB-2 protein overproduction based on strong immunoreactivity with two antibodies (TAB-250 and CB11), although no definite activation could be demonstrated by additional techniques. Three other tumors (6%) showed equivocal c-erbB-2 protein overproduction based on weak immunoreactivity only with TAB-250, although unequivocal activation could not be demonstrated by additional techniques. The 32 carcinomas (68%) that showed no significant immunoreactivity with any antibodies in routinely processed tissue also showed no detectable c-erbB-2 activation by additional techniques. We conclude that TAB-250 and CB11 are reliable antibodies for detecting c-erbB-2 protein overproduction in routinely processed tissue. TAB-250 also weakly stains a few tumors showing no definite c-erbB-2 activation by other techniques. Two additional antibodies (3B5 and N3/D10) detect c-erbB-2 protein overproduction in paraffin-embedded tissue, but are more difficult to interpret. A fifth antibody, TA-1, is an excellent reagent for use on frozen tissue, but prolonged formalin fixation may impair recognition of its antigenic epitope.

Small B-cell lymphoid neoplasms with coexisting T-cell lymphomas

The simultaneous occurrence of a small B-cell lymphocytic neoplasm and a T-cell lymphoma in the same lymph node biopsy specimen is documented in two patients. The biopsy from the first patient, who had a 5-year history of chronic lymphocytic leukemia, showed evidence of a small B-cell lymphocytic neoplasm coexisting with a large-cell lymphoma of T-cell phenotype. The lymph node biopsy specimen from the second patient showed features of small lymphocytic lymphoma of B-cell phenotype, coexisting with a small-cell pleomorphic lymphoma of T-cell phenotype. The lymph node specimens from both patients met strict criteria for composite lymphomas. The clinical and morphologic findings in the first patient are those of "Richter's transformation" of chronic lymphocytic leukemia. The lymph node biopsy specimens from these two patients demonstrate that small B-cell lymphocytic neoplasms may coexist with T-cell lymphomas.

Detection of metastatic neuroblastoma in bone marrow biopsy specimens with an antibody to neuron-specific enolase

To verify the practical utility of immunohistochemical analysis of bone marrow biopsy specimens in patients with neuroblastoma, we compared the results of routine histologic examination of 68 specimens with the results of immunohistochemical detection of tumor cells using an antibody to neuron-specific enolase (NSE). A commercially available polyclonal antibody to this enolase isoform consistently reacted with the neoplastic cells in biopsy specimens with histologic features diagnostic of (24 specimens) or suspicious for (one specimen) metastatic neuroblastoma. Immunohistochemical double-staining techniques documented that the NSE-positive neoplastic cells also reacted with antibodies to chromogranin and synaptophysin. Notably, anti-NSE detected small foci of metastatic neuroblastoma in two of 43 biopsy specimens that showed no evidence of metastatic tumor in the initial histologic sections. Rare NSE-reactive hematopoietic cells were present in approximately a third of the specimens with and those without neuroblastoma and were easily distinguished from metastatic tumor by morphologic examination. We conclude that this antibody to NSE consistently detects neuroblastoma cells in routinely processed bone marrow specimens, including small foci of tumor cells not evident in initial histologic sections.

Adenovirus in the gastrointestinal tracts of immunosuppressed patients

Adenovirus was cultured from various gastrointestinal sites and one lung specimen from seven immunosuppressed patients, four of whom were bone marrow transplant recipients. Histologic examination and in situ hybridization studies of the lung demonstrated adenovirus in the bronchial epithelium and alveolar lining cells. In contrast, none of the 34 gastrointestinal biopsies performed within 30 days of the positive adenovirus culture showed histologic or molecular evidence of invasive adenovirus in the gastrointestinal mucosa. These results suggest that isolation of adenovirus from gastrointestinal biopsy specimens taken from immunosuppressed patients probably does not indicate an invasive adenoviral infection.

B-cell lymphoproliferative disorders in solid-organ transplant patients: detection of Epstein-Barr virus by in situ hybridization

B-cell lymphoproliferative disorders (BLPDs) occur in approximately 2% of transplant recipients and are frequently fatal. Indirect serologic evidence has implicated Epstein-Barr virus (EBV) as an etiologic factor in these lesions. Direct evidence of the presence of EBV in these lesions has been obtained in relatively few cases. We used in situ hybridization (ISH) with a probe for the BamHI-W region of the EBV genome to study 52 tissue specimens from 28 solid-organ transplant patients who had BLPD. Epstein-Barr virus-infected lymphoid cells were identified in 26 of these 28 patients. The two patients without ISH evidence of EBV infection showed no distinctive clinical, morphologic, or serologic features. Previous filter-hybridization studies of these two patients had demonstrated evidence of EBV infection. Seven additional transplant patients without evidence of BLPD were studied as controls and showed no evidence of EBV in their lymphoid cells by ISH. These data provide further support for the etiologic role of EBV in the pathogenesis of posttransplantation lymphoproliferative disorders.

Infrequent detection of Toxoplasma gondii genome in toxoplasmic lymphadenitis: a polymerase chain reaction study

The diagnosis of toxoplasmic lymphadenitis is currently established by histologic evaluation with confirmation by serologic studies. We used a sensitive and specific polymerase chain reaction methodology for the identification of toxoplasmic genomes previously reported by others to investigate whether this technology could contribute to the diagnosis. We were able to reliably detect toxoplasmic genomes in paraffin-embedded tissues of toxoplasmic encephalitis and myocarditis, and serial dilution studies indicated a high degree of sensitivity. Nonetheless, we identified toxoplasmic genomes in frozen tissue from only one of nine cases of toxoplasmic lymphadenitis. In the one positive case, only one of three frozen samples from the lymph node biopsy was positive, indicating a focal infection within the lymph node. It is concluded that polymerase chain reaction studies, at their current level of sensitivity, are not of great use in contributing to the evaluation of cases of suspected toxoplasmic lymphadenitis, which continues to be best diagnosed by accurate histopathologic examination.

Clinical and pathologic significance of the c-erbB-2 (HER-2/neu) oncogene

Activation of the c-erbB-2 oncogene can occur by amplification of c-erbB-2 DNA and by overproduction of c-erbB-2 mRNA and c-erbB-2 protein. Approximately 20 percent of breast carcinomas show evidence of c-erbB-2 activation, which correlates with a poor prognosis primarily in patients with metastasis to axillary lymph nodes. Studies that have attempted to correlate c-erbB-2 activation with other prognostic factors in breast carcinoma have reported conflicting conclusions. The pathologic and clinical significance of c-erbB-2 activation in other neoplasms is unclear and should be assessed by additional studies.

B-cell lymphoproliferative disorders after bone marrow transplant. An analysis of ten cases with emphasis on Epstein-Barr virus detection by in situ hybridization

Ten patients with B-cell lymphoproliferative disorders (BLPD) after bone marrow transplant were studied in a retrospective analysis of 81 specimens available from biopsy and autopsy material. Histologic review, immunophenotyping, and in situ hybridization (ISH) for Epstein-Barr virus (EBV) sequences were done. Sixty-four specimens showed morphologic evidence of BLPD, demonstrating a heterogeneous spectrum with various degrees of plasmacytoid differentiation. Immunophenotypic evidence of clonality was found in six patients. The ISH detected EBV sequences in all ten patients, including 60 of the 64 specimens with morphologic evidence of BLPD. In addition, ISH identified EBV-infected lymphoid cells in two of 17 sites without morphologic evidence of BLPD. These data demonstrate the utility of ISH for detecting EBV genome in this setting and provide further evidence for the etiologic role of EBV in the pathogenesis of BLPD.

Lack of evidence for involvement of Epstein-Barr virus in the development of the "Quilty" lesion of transplanted hearts: an in situ hybridization study

We investigated the possible relationship of Epstein-Barr virus to the development of subendocardial lymphocytic infiltrates. In situ hybridization for Epstein-Barr virus genomic sequences was performed in 22 heart biopsy specimens with subendocardial infiltrates for 19 heart transplant patients. Epstein-Barr virus genomic sequences were not detected in the lymphocytes or myocytes in any of the heart biopsy specimens. We conclude that Epstein-Barr virus is not related to the development of subendocardial lymphocytic infiltrates.