Primary extranodal soft tissue lymphoma of the extremities

Since true primary lymphomas of soft tissues are extremely rare and there are few well-documented cases in the literature, we report eight cases to help define the clinical and pathologic features of this type of extranodal lymphoma. Among 7,000 malignant lymphomas seen at Mayo Clinic over a 10-year period, we found eight cases of Stage IAE extranodal malignant lymphoma that presented as a soft tissue mass in the upper or lower extremities. The tumors occurred in the following sites: thigh (n = 4), upper arm (n = 2), ankle (n = 1), and calf (n = 1). Two cases had low-grade histology: small lymphocytic lymphoma and follicular mixed small-cleaved and large-cell lymphoma. An intermediate-grade histology was present in two cases: diffuse mixed small- and large-cell lymphoma and diffuse large-cell (cleaved) lymphoma. Half of the patients had a high-grade lymphoma: diffuse large-cell (n = 3) and large-cell, immunoblastic (n = 1). The results of immunohistochemistry and electron microscopy in selected cases are discussed in the context of the differential diagnosis with other small, round-cell cancers. Four patients died of recurrent lymphoma, one at 7 months, two at 15 months, and one at 4 years. Three patients are alive without evidence of disease at 3, 8, and 13 years. One patient is alive and is receiving chemotherapy for locally recurrent lymphoma 6 months after diagnosis.     

Primary lymphoma of bone. A B-cell neoplasm with a high frequency of multilobated cells

Primary lymphoma of bone is an uncommon neoplasm that can be difficult to diagnose and subclassify. Only in a few cases has the immunophenotype been determined with monoclonal antibodies. We evaluated the histological features and immunophenotype of 12 cases of primary lymphoma of bone. The patients ranged in age from 16 to 80 years (mean, 41 years) with a male:female ratio of 1:1. The sites involved included femur (three cases), humerus (two cases), tibia (three cases), pelvis (two cases), ulna (one case), and scapula (one case). All cases were diffuse large-cell lymphomas: nine large-cleaved (eight with multilobated cells), two large-cell not otherwise specified, and one immunoblastic. Sclerosis was noted in six cases. Immunohistochemical studies on frozen-tissue sections demonstrated staining with the following antibodies: 11 of 11 with CD45, 12 of 12 with CD20, eight of 12 with monotypic immunoglobulin (six IgG, two IgM, seven kappa, one lambda). Tumor cells were negative for T-cell markers in each case. Ten patients are alive and well 0.5-4.5 years (median, 1.5 years) following treatment with radiation or chemotherapy. Two patients had recurrence at another site 0.75 years and 4 years after the initial diagnosis, respectively. Primary bone lymphoma is a B-lineage large-cell lymphoma with an unusually high incidence of large-cleaved and multilobated cells. The frequency of IgG heavy chain expression suggests a post-germinal center stage of differentiation. Frozen section immunohistologic studies are useful in the diagnosis of this tumor. Aggressive therapy has resulted in a favorable outcome in most cases.     

Sinonasal lymphoma: a clinicopathologic analysis of 58 cases from the Massachusetts General Hospital.

Few large series compare lymphomas of the nasal cavity with those of the paranasal sinuses. We studied the cases of 58 patients, 34 males and 24 females, aged 7 to 92 years (mean, 57 years), who had lymphoma involving the nasal cavity or paranasal sinuses. Thirty-three patients had diffuse large B-cell lymphoma (DLBCL). Twenty-three were male and 10 were female, with an age range of 7 to 91 years (mean, 63 years); two were HIV-positive. Only 2 of 11 cases tested (one in an HIV-positive patient and one of lymphomatoid granulomatosis type) were Epstein-Barr virus (EBV)-positive. Thirty (91%) involved paranasal sinuses, 10 with nasal involvement, whereas three cases had nasal, but not sinus, involvement. At last follow-up, 16 (67%) were free of disease 7 to 169 months later (mean, 65 months), and 8 (33%) had died of disease 2 to 166 months later (mean, 45 months). Seventeen patients had nasal-type natural killer (NK)/T-cell lymphoma. There were 10 women and 7 men, aged 27 to 78 years (mean, 48 years). Thirteen of 14 were EBV-positive. Sixteen patients had nasal involvement, eight with sinus involvement. Eleven (73%) of 15 were alive and well 6 to 321 months later (mean, 139 months), three (20%) died of lymphoma 1, 11, and 12 months later, and one (7%) is alive with disease. There was one case each of marginal zone B-cell lymphoma, Burkitt's lymphoma, Burkitt-like lymphoma, peripheral T-cell lymphoma of unspecified type, and adult T-cell lymphoma/leukemia. In an additional three cases, the lymphomas were composed predominantly of large cells, but no immunophenotyping could be performed for subclassification. In 19 cases (17 DLBCLs, 1 Burkitt-like lymphoma, and 1 lymphoma of uncertain lineage), presenting symptoms included complaints related to the eyes. In 16 cases (13 DLBCLs, 1 Burkitt-like lymphoma, 1 nasal NK/T-cell lymphoma, and 1 lymphoma of uncertain lineage), the orbit was invaded by lymphoma. In our series, the most common lymphoma to arise in the sinonasal area is DLBCL, followed by nasal NK/T-cell lymphoma. Comparison of these two types of lymphoma showed that lymphomas involving sinuses without nasal involvement were predominantly DLBCLs (20 of 21), whereas nasal cavity lymphomas without sinus involvement were usually NK/T-cell type (8 of 11) (p = 0.000125). Compared with patients with DLBCL, patients with nasal NK/T-cell lymphoma were overall younger, with a lower male-to-female ratio. Lymphomas of B-cell lineage were more likely to be associated with symptoms related to the eyes (p < 0.0005) and to have extension to the orbit (p < 0.01) than were lymphomas of T- or NK-cell lineage. In contrast to results of Asian studies in which nasal NK/T-cell lymphoma has a very poor prognosis, our nasal NK/T-cell lymphomas had an outcome similar to that of DLBCL.     

Non-Hodgkin's lymphomas of the lung. A study of 19 cases emphasizing the utility of frozen section immunologic studies in differential diagnosis

Nineteen cases of possible non-Hodgkin's lymphoma of the lung were studied by conventional morphologic methods and by immunohistochemical methods employing monoclonal antibodies applied to frozen tissue sections. In five of the 19 cases, the original histologic diagnoses were revised after review of the immunologic findings. Problem areas clarified by immunodiagnosis included the differential diagnoses of pseudolymphoma versus small lymphocytic lymphoma (two cases), Hodgkin's disease versus non-Hodgkin's lymphoma (two cases) and non-Hodgkin's lymphoma versus lymphomatoid granulomatosis (one case). Of the seven lymphomas presenting exclusively in the lung without a prior history of lymphoma, three were small lymphocytic, one was diffuse mixed small cleaved and large cell, and three were diffuse large-cell lymphomas. Four of these lymphomas typed as B-cell, two typed as T-cell, and one was of undefined phenotype.     

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

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

The value of immunophenotyping on paraffin sections in the identification of T-cell rich B-cell large-cell lymphomas: lineage confirmed by JH rearrangement

Immunophenotyping of lymphomas using paraffin-embedded lymphoid tissue, not previously distorted by frozen section, is useful in identifying the large neoplastic B cells that may be in the minority in T-cell rich B-cell lymphoma (TCRBCL). Even in cases in which frozen tissue sections are available, the improved morphology in unfrozen sections allows the proper classification of these lymphomas as large cell and identifies their B-cell lineage, which is important for clinical therapeutic studies. Seven cases initially believed to be diffuse mixed cell lymphoma of possible peripheral T-cell lineage showed the large cells to be immunoreactive with L-26 (pan B-cell marker) with the majority of smaller lymphocytes immunoreactive for UCHL-1 and Leu-22 (pan T-cell markers). K/lambda immunostaining on frozen sections was equivocal. In these cases, the diagnosis of large-cell lymphoma of B-cell lineage was confirmed by detection of immunoglobulin heavy- (all seven cases) and light- (six of seven cases) chain gene rearrangements, with germ-line configuration of the T-cell receptor beta-chain gene (all cases). Some cases of TCRBCL may not show detectable rearrangement of the immunoglobulin genes because of the low concentration of neoplastic cells in the samples submitted. The presence of rearrangements in these seven cases, however, supports the diagnosis of TCRBCL based on paraffin immunophenotyping when frozen tissue is not available or when molecular studies are not feasible. Although these seven cases are classified as large-cell lymphoma, an intermediate-grade lymphoma, the influence of the reactive T-cell population on the clinical behavior will require follow-up studies.     

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

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

Simultaneous lymphocyte predominant Hodgkin's disease and large-cell lymphoma

Lymphocyte-predominant Hodgkin's disease (LPHD) is a subtype of Hodgkin's disease characterized by an indolent clinical course and by distinctive histological and immunological features. Coexistence of diffuse or nodular LPHD with large-cell non-Hodgkin's lymphoma (NHL) distant from the presenting site has rarely been reported. We studied three cases of simultaneous LPHD and large-cell NHL. Two cases involved men, aged 66 and 20 years, with neck and axillary masses, respectively. Biopsy of each mass revealed nodular LPHD. In one case the spleen contained areas of both LPHD and large-cell NHL, whereas only large-cell NHL was found in the spleen of the other patient. The patients are alive 49 months and 29 months after diagnosis. The third case was from a 4-year-old boy with a neck mass that revealed both diffuse LPHD and areas of large-cell NHL. Local recurrence prompted therapy, and the boy is in complete remission 31 months after diagnosis. Immunophenotyping in all three cases showed the Reed-Sternberg variant lymphocytic and histiocytic cells to be B-lymphocytes. The NHL cells in two cases were B-cells; in the child, the cells reacted only with leukocyte common antigen. Immunoglobulin heavy- and light-chain genes were rearranged in the NHL cells in the spleen of one case, and heavy-chain genes were rearranged in the lymph node of the child. It appears that when large-cell NHL and LPHD occur simultaneously, even when the large-cell NHL occurs at a site distant from the LPHD, the patient's clinical course is like the indolent course of LPHD rather than like the typically aggressive course of large-cell NHL. This clinical course, together with immunophenotyping and genotyping studies, suggests a developmental relationship between these two lymphomas when they occur simultaneously.     

Mediastinal diffuse large-cell lymphoma with sclerosis. A clinicopathologic study of 60 cases

A retrospective analysis was conducted of 60 cases of mediastinal diffuse large-cell lymphoma with sclerosis (MDLLS). The study group consisted of 43 females and 17 males. Eighty-five percent were 35 years of age or younger at time of initial diagnosis. Thirty are alive and well at least 1 year after diagnosis (median: 34.5 months), six are alive with disease (median: 13 months), 20 died of disseminated disease (median: 16.5 months), and four died of other causes. Complete autopsy was performed on eight of the patients who died of disease. The most frequently involved extrathoracic organs were lymph nodes, kidney, liver, pancreas, gastrointestinal tract, and ovary. Fifty-six cases were classified according to the Lukes-Collins scheme: 35 were follicular center cell, 13 immunoblastic T (IBT), seven immunoblastic B (IBB), one a composite of IBB and nodular sclerosing Hodgkin's disease; four cases were unclassifiable. Lymphoreticular origin was proven immunohistochemically in 53 cases, including the four unclassifiable examples and eight cases typed as B-cell tumors. Unfavorable prognostic factors were age less than 25 years at diagnosis, tumor outside the thoracic cavity at presentation, disease recurrence, and IBT or IBB tumor histology. Favorable signs were good response to initial therapy and marked tumor sclerosis. MDLLS is most often mistaken for malignant thymoma, seminoma, and Hodgkin's disease. Criteria helpful for the recognition of MDLLS are discussed.     

Lymphoma of the ocular adnexa: A study of 353 cases

We studied the cases of 353 patients with lymphoma involving the ocular adnexa diagnosed at the Massachusetts General Hospital between 1974 and 2005. The patients included 153 males and 200 females, aged 7 to 95 years, with a mean age of 64 years. In 277 cases, there was no known history of lymphoma. Seventy-six patients had a history of lymphoma, with the ocular adnexa being involved at relapse or with progression of the previously diagnosed lymphoma. The patients had marginal zone lymphoma (182 cases), follicular lymphoma (80 cases), mantle cell lymphoma (18 cases), small lymphocytic lymphoma/chronic lymphocytic leukemia (13 cases), lymphoplasmacytic lymphoma (4 cases), splenic marginal zone lymphoma (2 cases), low-grade B cell, not subclassified (19 cases), precursor B lymphoblastic lymphoma (3 cases), diffuse large B-cell lymphoma (26 cases), and 1 case each of high-grade B-cell lymphoma, not subclassified, peripheral T-cell lymphoma, unspecified type, extranodal NK/T-cell lymphoma, nasal type, and Hodgkin lymphoma, nodular sclerosis type. Almost all marginal zone lymphoma patients (168 of 182, 92%) had primary ocular adnexal lymphoma. Fourteen marginal zone lymphoma patients (8%) had a prior history of lymphoma, usually arising in another extranodal site. Twenty-five of 80 (31%) follicular lymphoma patients had a prior history of lymphoma, usually arising in lymph nodes. Patients with mantle cell lymphoma, chronic lymphocytic leukemia, lymphoplasmacytic lymphoma, and splenic marginal zone lymphoma almost always had a prior history of lymphoma or were known to have widespread disease at the time of diagnosis of ocular adnexal lymphoma. A subset of the diffuse large B-cell lymphomas were associated with large destructive masses involving adjacent structures such as paranasal sinuses, raising the possibility that they may have arisen from one of the adjacent structures and involved the ocular adnexa by direct extension. The relatively high proportion of low-grade lymphoma, not subclassified, highlights the difficulty that may arise in distinguishing different types of low-grade lymphoma, particularly when biopsies are small and artifactually distorted. Ocular adnexal lymphoma is primarily a disease of older adults, with a slight female preponderance. Most lymphomas are low-grade B-cell lymphomas, with marginal zone lymphoma being by far the most common type. Marginal zone lymphoma typically involves the ocular adnexa primarily, whereas other types of low-grade B-cell lymphoma often involve the ocular adnexa secondarily. High-grade B-cell lymphomas only occasionally involve the ocular adnexa, and T-cell lymphoma, NK-cell lymphoma, and Hodgkin lymphoma are only rarely encountered in this site.     

Extranodal NK/T-cell lymphoma presenting as a pituitary mass. Case report and review of the literature

Primary pituitary lymphomas (PPLs) are rare tumors of the central nervous system, and most are of B-cell origin. Extranodal NK/T-cell lymphomas are uncommon neoplasms that are highly aggressive and show a strong association with Epstein-Barr virus. They most commonly affect the nasal cavity and paranasal sinuses; manifestation as a primary pituitary tumor has never been described. The authors report a case of NK/T-cell lymphoma of the pituitary gland and review 17 cases of PPL from the literature. All patients had been evaluated at presentation for clinical, neuroimaging, and histopathological findings. Patients who had systemic lymphoma with secondary involvement of the pituitary gland were excluded. The mean patient age was 55.5 years (range 26-86 years); the male/female ratio was 13:5. The most common presentation was pituitary insufficiency (72%), followed by headache (56%), diplopia (39%), visual loss (28%), and fever (22%). Thirteen patients (72%) exhibited anterior hypopituitarism and seven (39%) had diabetes insipidus at presentation. Magnetic resonance imaging demonstrated enhancing parasellar masses with diffuse enlargement of the pituitary gland (94%), suprasellar extension (44%), cavernous sinus extension (39%), and stalk thickening (22%). Thirteen patients (72%) had B-cell lymphoma, four (22%) had T-cell lymphoma, and one (6%) had NK/T-cell lymphoma. Primary pituitary lymphomas are rare entities with a range of clinical presentations and neuroimaging findings that are unique from those of patients who present with pituitary adenomas. The pathological entity of NK/T-cell lymphoma is distinct, and its course is very aggressive with a poor prognosis.     

Most nasal/nasopharyngeal lymphomas are peripheral T-cell neoplasms

Eleven consecutive cases of nasal/nasopharyngeal lymphoma were studied histologically and with a panel of monoclonal antibodies. The disease showed a male predominance and occurred over a wide age range, with a median of 52 years. Five patients had midfacial destructive disease, and six had gross tumor masses involving the nose/nasopharynx. Three cases were classified as small cleaved cell, two cases as mixed cell, five cases as large cell, and one case as immunoblastic lymphoma. Those belonging to the first two categories also satisfied the diagnostic criteria of so-called polymorphic reticulosis. Epithelial invasion, angioinvasion, and coagulative necrosis were demonstrated in seven, eight, and nine cases respectively. Immunohistochemical studies confirmed that the atypical cells of all 11 cases exhibited T-cell markers. All but one case had lost one or more T-cell markers associated with peripheral T cells, particularly T1 and T3. Loss of T-cell markers in the five cases histologically consistent with polymorphic reticulosis provided further support to indicate that the lesion was neoplastic. A significant proportion of cases also expressed the activated T-cell markers 12 (HLA-DR) and interleukin-2 receptor (IL-2R1).     

Clinical relevance of three subtypes of primary sinonasal lymphoma characterized by immunophenotypic analysis

BACKGROUND: The purpose of this study was to investigate the clinical relevance of subtypes categorized by immunophenotypic analysis in primary sinonasal lymphomas. METHODS: Eighty patients with localized non-Hodgkin's lymphoma involving the nasal cavity and/or paranasal sinuses were divided into three subtypes on the basis of their immunohistochemical findings: (A) B-cell lymphoma (n = 19), (B) T-cell lymphoma (n = 27), and (C) natural killer (NK)/T-cell lymphoma (n = 34). The clinicopathologic profiles, immunophenotypic data, patterns of treatment failure, and survival data among the three patient groups were retrospectively compared. RESULTS: The nasal cavity was the predominant site of involvement in T-cell and NK/T-cell lymphoma, whereas sinus involvement without nasal disease was common in B-cell lymphoma. Systemic B symptoms were frequently observed in NK/T-cell lymphoma. Almost all patients with NK/T-cell lymphoma showed a strong association with the Epstein-Barr virus by in situ hybridization studies. Sixty-five patients (81%) patients achieved complete remission after initial treatment, but 36 (55%) of these subsequently experienced treatment failure. Although there were no significant differences in locoregional failure rates among the patients of the three groups, distant failure was far more common in B-cell or NK/T-cell lymphoma than in T-cell lymphoma (p =.005). Most B-cell lymphoma cases showed a predilection for sites of systemic failure in the nodal and extranodal sites below the diaphragm, such as the paraaortic lymph nodes or the gastrointestinal (GI) tract, whereas patients with NK/T-cell lymphoma showed an increased risk of systemic dissemination to the skin, testes, or GI tract, including the development of hemophagocytic syndrome. The 5-year actuarial and disease-free survival rates for all patients were 57% and 51%, respectively. Of the three subtypes of primary sinonasal lymphomas, T-cell lymphoma seemed to carry the most favorable prognosis and NK/T-cell lymphoma the worst. (The 5-year actuarial survival rate was 57% for B-cell lymphoma, 80% for T-cell lymphoma, 37% for NK/T-cell lymphoma; p =.02, log-rank.) By univariate and multivariate analyses, immunophenotype was identified as the most important prognostic factor. CONCLUSIONS: Our data indicate that the three subtypes of primary sinonasal lymphomas classified by immunohistochemical studies exhibit different clinical profiles, different patterns of failure, and different treatment outcomes. Given these observations, it is concluded that the recognition of these distinct subsets, diagnosed on the basis of immunophenotypic study, is very important and clinically relevant in predicting their potential behavior and prognosis.     

Primary large cell lymphoma of the mediastinum. A histologic and immunophenotypic study of 29 cases

We studied the morphologic and immunologic features of 29 cases of primary nonlymphoblastic non-Hodgkin's lymphoma of the mediastinum. The patients ranged in age from 15 to 73 years, with a median of 32 years. The mean age for the 11 men (50 years) was significantly higher than that for the 18 women (32 years) (p less than 0.05). All had diffuse large cell lymphomas (six immunoblastic, 14 large cell not otherwise specified, six large cell noncleaved, one large cell cleaved, and two not subclassifiable). Sclerosis was prominent in 11 cases, none of them immunoblastic, and did not correlate with superior vena cava syndrome. The mean age (54 years) of patients with immunoblastic lymphomas was higher than that for patients with other subtypes (35 years) (p less than 0.02). Frozen-section immunoperoxidase staining disclosed monotypic immunoglobulin in 13 cases, with a high frequency of heavy-chain class switching (seven IgG, two IgA, four IgM). Sixteen cases were immunoglobulin negative; 14 of 15 cases expressed B-lineage antigens, and none expressed T-lineage antigens. Three of four cases showed immunoglobulin heavy- or light-chain gene rearrangement by the Southern blot technique. None showed rearrangement of the T-cell receptor beta-chain-gene constant region. There was no correlation between immunophenotype and morphologic subtype. The immunoglobulin-negative group was predominantly female (13 of 16 cases; p less than 0.02), and younger (mean age, 34 years versus 44 years; p = NS) than the immunoglobulin-positive group; however, the difference in age was not statistically significant. The actuarial 5-year survival was 57%, and there was no correlation between survival and either histologic subtype or immunophenotype. Mediastinal large cell lymphoma is a B-cell tumor, which frequently lacks immunoglobulin, may be primary in the thymus, has a predilection for young women, and can be cured with aggressive therapy.     

Histological and immunohistological findings in lymphoepithelioid cell lymphoma (Lennert's lymphoma)

Four hundred and two cases considered or suspected to be lymphoepithelioid cell lymphoma (Lennert's lymphoma) were analyzed morphologically, immunohistochemically, and clinically. One hundred and eight of these cases, investigated in 180 biopsies, fulfilled the morphological and immunohistochemical criteria for lymphoepithelioid cell lymphoma and are herein reported. Cellular composition and histological structure are described in detail as a basis for discriminating Lennert's lymphoma from similar lymphomas with a high content of epithelioid cells (Hodgkin's disease, AILD type of T-cell lymphoma, lymphoplasmacytic lymphoma) and from inflammatory epithelioid cell reactions. Single typical Hodgkin cells were found in only 3.8% of biopsy specimens examined, and single typical Sternberg-Reed cells were found in only 2.2% of the biopsy specimens examined. Because these single Hodgkin and Sternberg-Reed cells were situated in a relatively monotonous lymphoid cellular pattern and because both these cells types also may occur in peripheral T-cell lymphomas, we include cases with such cells in the category of Lennert's lymphoma. Eight percent of the patients with lymphoepithelioid cell lymphoma showed transformation into a large-cell T-cell lymphoma without the prominent focal epithelioid cell component previously observed. Immunohistochemically, seven of the 69 biopsy specimens with detectable giant cells stained positively for the granulocyte-specific monoclonal antibody 3C4 (approximately CD15). Plasma cells were rare and always showed a polytypic immunoglobulin pattern. Lymphoepithelioid cell lymphoma, defined as a lymphoma of CD4+ T lymphocytes, marks the border between Hodgkin's disease and the non-Hodgkin's lymphomas. Today, absolute criteria for distinguishing between these two classes of lymphoma are lacking.     

Primary T-cell lymphoma of the duodenum: Report of a case

A case of primary non-Hodgkin's T-cell lymphoma of the duodenum is presented. A 41-year-old man was hospitalized in 1984 complaining of abdominal distention and vomiting. Hypotonic duodenography showed an encircling filling defect in the second portion of the duodenum, and a biopsy specimen revealed features of malignancy suggestive of either undifferentiated carcinoma or malignant lymphoma. Radical surgery (pancreaticoduodenectomy) was performed, after which chemotherapy was administered. A histological evaluation of the duodenal tumor showed it to be non-Hodgkin's lymphoma. It was a diffuse, large-cell type, which immunohistochemically suggested it to be of T-cell origin. Currently the patient is doing well, with no evidence of disease recurrence 13 years after surgery.     

Peripheral T-cell lymphoma with Reed-Sternberg-like cells of B-cell phenotype and genotype associated with Epstein-Barr virus infection.

We report three cases of nodal peripheral T-cell lymphoma (PTCL) with Reed-Sternberg-like (RS-like) cells of B-cell pheno- and/or genotype. Histologic analysis in all cases revealed diffuse nodal effacement by atypical lymphoid cells of variable size. Two of the three cases had features of angioimmunoblastic T-cell lymphoma (AILT). Large mononuclear and binucleated cells with prominent eosinophilic nucleoli and abundant cytoplasm resembling classic RS cells and mononuclear variants were scattered throughout all biopsies. The lymphoma cells in the three cases were of T-cell lineage (CD3+, CD43+, and CD45RO+). The RS-like cells from all cases were CD30 and CD15 positive. In contrast to the neoplastic T cells, the RS-like cells lacked all T-cell markers and in two cases were positive for CD20. Epstein-Barr virus (EBV) latent membrane protein 1 (LMP1) and EBER 1 (2/2) were detected in the RS-like cells in all cases. The neoplastic T cells were negative for EBV. Polymerase chain reaction (PCR) analysis demonstrated clonal rearrangements of the T-cell receptor gamma chain gene in the three cases. PCR analysis of microdissected RS-like cells for immunoglobulin heavy chain gene rearrangements in cases 1 and 3 showed an oligoclonal pattern. The presence of RS-like cells in PTCL represents a diagnostic pitfall, because in one case this observation led to a misdiagnosis of Hodgkin's disease (HD). The oligoclonal expansion of EBV-infected cells may be related to underlying immunodeficiency associated with T-cell lymphomas and AILT in particular. This phenomenon may provide the basis for some cases of Hodgkin's disease after T-cell lymphomas and suggests that they are clonally unrelated neoplasms. The expression of LMP1 appears to be crucial for the immunophenotype and probably for the morphology of the RS and RS-like cells appearing in diverse lymphoid malignancies, including HD, chronic lymphocytic leukemia, and PTCL.     

Malignant lymphoma of the testis: histological and immunohistological study of 28 cases

Histological and immunohistological studies were made in 28 patients with testicular lymphoma who presented with a right (15), left (11) or bilateral (2) scrotal swelling. Patient age at hospitalization ranged from 39 to 87 years, with a median age of 64 years. The disease was stage 1 in 12 patients, stage 2 in 11 and stage 3 in 5. Histologically, most of the neoplasms were of the diffuse large cell type, with an immunoblastic type being the most common. Immunohistochemistry revealed that all but 2 cases were of the B cell type. None of the tumors reacted with monoclonal antibody for T cell. These findings suggested that testicular lymphoma exclusively consisted of the B cell type, identical to previous reports of extranodal lymphomas other than those in the skin. The pertinent literature is reviewed and the histogenesis of testicular lymphoma is discussed.