Immunohistological characterization of malignant lymphomas of the Waldeyer''s ring other than the nasopharynx

Among extranodal lymphomas, the Waldeyer's ring is the second most frequently involved site after the gastrointestinal tract. Fresh tissue from 23 consecutive cases of malignant lymphoma of the faucial tonsil, palate and base of tongue were studied histologically and with a panel of 25 monoclonal antibodies. Twenty cases were primary Waldeyer's ring lymphoma, and all were found to express B-cell phenotype. Most cases were classified as diffuse centroblastic lymphoma, polymorphic subtype, in which there were immunoblast-like, centrocyte-like and/or multilobated centroblasts. All except one case expressed all three B-cell lineage antigens CD19, CD20 and CD22, but they showed inconsistent expression of the B-cell antigens CD9 and CD24. Four cases lacked surface immunoglobulin. Six cases expressed interleukin-2 receptor, suggesting that they were composed of highly activated B-cells. Three cases represented relapse in the tonsil or tongue in patients with known malignant lymphoma in other sites; one case expressed T-cell and two cases B-cell phenotype (both of which also expressed interleukin-2 receptor). The clinical features and immunohistological findings suggest that Waldeyer's ring lymphomas, other than those of the nasopharynx, share some of the characteristics of 'mucosa-associated lymphoid tissue' lymphomas. In contrast, nasopharyngeal lymphomas are more related to nasal lymphomas, and are almost exclusively peripheral T-cell neoplasms.     

EBV in situ hybridization study for non-Hodgkin's lymphomas.

Epstein-Barr virus(EBV) has been implicated in the pathogenesis of B-lymphoproliferative disorders, T-cell lymphomas and Hodgkin''s disease. In this report, we performed an in situ hybridization study on EBV genome in 10 cases of nasal non-Hodgkin''s lymphoma(NHL), 20 cases of Waldeyer''s ring(WR) NHL, and 20 cases of nodal NHLs to document EBV association with lymphomas in Koreans. For immunophenotyping, monoclonal antibodies for CD 20, MB 2, CD 45Ro & CD 43 were used. For in situ hybridization study, EBV DNA probe for Bam HI ''V'' fragment and EBV RNA probe for EBER and BHLF were used. Twenty two cases(44%) of malignant lymphomas were positive for EBV genome. Generally, T-cell lymphomas showed a higher positive rate(61%) than B-cell lymphomas(24%). Among T-cell lymphomas, nasal lymphomas showed a higher positive rate(80%) than WR(50%) or nodal lymphomas(50%). Of 22 EBV genome positive cases, 10 cases were positive for EBER, 10 cases for BHLF, and 2 cases for both EBER and BHLF. The histologic types by Working Formulation(WF) were not correlated with EBV genome positive rate, whereas lymphomas showing the histologic spectrum of polymorphic reticulosis(PR) showed a higher positive rate(65%) than lymphomas without PR-like features(40%). These results indicate that nasal T-cell lymphomas with the histologic spectrum of PR are strongly associated with EBV and that the anatomic site may be an important factor in this association.     

Lymphoid lesions of the head and neck: a model of lymphocyte homing and lymphomagenesis.

Lymphoid lesions of the head and neck mainly affect the nasopharynx, nasal and paranasal sinuses, and salivary glands. These three compartments each are affected by a different spectrum of lymphoid malignancies and can serve as model for mechanisms of lymphomagenesis. The type of lymphoma seen reflects the underlying biology and function of the particular site involved. The nasopharynx and Waldeyer's ring are functionally similar to the mucosal associated lymphoid tissue (MALT) of the gastrointestinal tract and are most commonly affected by B-cell lymphomas, with mantle cell lymphoma being a relatively frequent subtype. The most prevalent lymphoid lesion of the salivary gland is lymphoepithelial sialadenitis, associated with Sj?gren's syndrome. Lymphoepithelial sialadenitis is a condition in which MALT is acquired in a site not normally containing lymphoid tissue. Patients with Sj?gren's syndrome are at increased risk to develop B-cell lymphomas, most commonly MALT lymphomas. The nasal and paranasal sinuses are the prototypical site for the development of extranodal natural killer (NK) /T-cell lymphoma, nasal type. This condition must be distinguished from other conditions causing the clinical picture of lethal midline granuloma, including Wegener's granulomatosis and infectious disorders. Lymphomatoid granulomatosis is common in the lung but is rarely seen in the midline facial structures.     

Low-grade B-cell lymphoma of mucosa-associated lymphoid tissue type in Waldeyer's ring

Amongst a total of 329 cases of low-grade B-cell lymphoma of Waldeyer's ring, we identified 12 cases that corresponded histomorphologically to low-grade B-cell lymphoma of mucosa-associated lymphoid tissue (MALT) type. These lymphomas are characterized by an extrafollicular growth pattern, often with a marginal zone-like arrangement, and by the centrocyte-like morphology of the tumour cells. They have not been described previously in this location. They predominantly affected the palatine tonsil. Ten cases were primary lymphomas of Waldeyer's ring. In two cases there was a simultaneous high-grade component. Two cases showed regional spread to cervical lymph nodes, but there was no widespread nodal involvement at the time of diagnosis. Immunohistochemically, all cases displayed B-cell markers and light chain restriction. Tropism of tumour cells for the epithelium was a consistent finding. In two cases involvement of Waldeyer's ring was secondary; in one of them the primary tumour was a gastric low-grade B-cell lymphoma of MALT type and in the other a high-grade B-cell non-Hodgkin's lymphoma of the stomach. These findings indicate that low-grade B-cell lymphomas of MALT type occurring in Waldeyer's ring should be included amongst the tumours of the MALT system. We surmise that in Waldeyer's ring such tumours are derived from the marginal zone, as has already been postulated for similar gastric tumours.     

Clinicopathological analysis of 501 non-Hodgkin's lymphomas in Korea according to the revised European-American classification of lymphoid neoplasms

AIMS: The clinical relevance of the Revised European-American Classification of Lymphoid Neoplasms (REAL) is still debated. To test the clinical validity of the REAL classification in Korea, where the incidence of T-cell lymphoma is higher, we investigated the clinicopathological features of non-Hodgkin's lymphoma (NHL) from Korea Cancer Center Hospital. METHODS AND RESULTS: Five hundred and one patients with NHL were reclassified according to the REAL classification and clinicopathologically analysed. Immunophenotypically, B-cell lymphoma accounted for 67.9% and T- and NK-cell type for 30.5%. Approximately 48.5% of cases were forms of diffuse large B-cell lymphoma (DLBCL), while only 5.4% were follicular lymphoma. Peripheral T-cell lymphoma unspecified (PTCL-U; 10.8%) and angiocentric lymphomas (11.8%) comprised the majority of T-cell lymphomas. Most of the angiocentric lymphomas presented with localized nasal/nasopharyngeal or tonsillar primaries. All peripheral T-cell lymphomas (PTCL) showed a significantly low overall survival compared to DLBCL (P = 0.02, log rank). Overall survival rates for DLBCL and PTCL-U were also significantly different (P = 0.0043, log rank), though for DLBCL and angiocentric lymphoma there was no significant difference (P = 0.2142, log rank). Angiocentric lymphoma, however, was characterized by a shorter median survival time than DLBCL (54 months vs. 96 months). Among DLBCL patients according to the REAL classification, overall survival was significantly better in nonimmunoblastic type (intermediate-grade, WF-F,G) as compared to large cell immunoblastic type (high-grade, WF-H) (log rank, P < 0.001). The morphological distinction of the immunoblastic and nonimmunoblastic among DLBCL of the REAL classification bears significant prognostic relevance worthy of further consideration. CONCLUSION: We conclude that lineage assignment (T vs. B) in the REAL classification is a clinically important distinction, but that it is necessary to subdivide the broad category of DLBCL.     

Marginal zone B-Cell lymphoma among primary B-Cell lymphoma of Waldeyer's ring: histopathologic and immunohistochemical study of 16 tonsillectomy specimens

Two subtypes of marginal zone B-cell lymphoma (eg, mucosa-associated lymphoid tissue [MALT] type and splenic type) have been reported in the lymph node. To determine the presence or absence of marginal zone B-cell lymphoma of MALT type and the splenic type among Waldeyer's ring (WR) lymphomas, 16 tonsillectomy specimens were studied. Ten cases (63%) were marginal zone B-cell lymphoma. Among marginal zone B-cell lymphoma, 7 were the MALT type and the remaining 3 cases of marginal zone B-cell lymphoma were the splenic type. Moreover, 4 cases of 7 MALT-type lymphomas contained numerous large cells (diffuse large B-cell lymphoma arising from a low-grade marginal zone B-cell lymphoma of MALT type). The low incidence of primary mucosa-associated lymphoid tissue type lymphoma of WR in previous reports may be because it is difficult to correctly identify the characteristic histologic findings of MALT-type lymphoma because of the small biopsy size.     

Clinicopathological analysis of 143 primary malignant lymphomas in the small and large intestines based on the new WHO classification

AIM: To study the clinicopathological and immunohistochemical features of 143 cases of primary small and large intestinal non-Hodgkin's lymphoma (NHL) in Japanese patients who presented between 1981 and 2000. METHODS AND RESULTS: The new World Health Organization (WHO) classification was used to classify NHL. The patients included 109 males and 34 females, with an average age of 54.1 years. Tumour sites were as follows: ileocaecal (n = 51, 35.7%), ileum (n = 29, 20.3%), rectum (n = 13, 9.1%), and duodenum (n = 11, 7.7%). Macroscopically, 124 cases (86.7%) were classified as tumorous type, 12 (8.4%) as diffuse infiltration type (erosion, superficial ulceration), five (3.5%) as polyposis type, and only two cases (1.4%) as ulceration type. Immunohistochemically, 122 lesions (85.3%) were of B-cell phenotype and 21 lesions (14.7%) were of T-cell phenotype. According to the WHO classification, of the B-cell lymphomas, 84 cases (68.9%) were large cell, 16 (13.1%) were Burkitt, 10 (8.2%) were marginal zone B-cell lymphomas of mucosa-associated lymphoid tissue (MALT), and seven (5.7%) were mantle cell tumours. Among the T-cell lymphomas, 15 (71.4%) were of unspecified type, two (9.5%) were natural killer type, two were anaplastic large-cell lymphomas, one was lymphoblastic, and one was an adult T-cell leukaemia lymphoma. The survival rate for T-cell lymphomas was poorer than for B-cell lymphomas. Among the B-cell lymphomas, mantle cell lymphoma tended to have a poorer prognosis, whereas MALT lymphomas had a better prognosis than other B-cell tumour types. CONCLUSIONS: Our retrospective study of patients with primary malignant lymphomas in the small and large intestines has illustrated the clinical features and outcomes of patients with this disease.     

Histological and immunohistochemical studies on primary gastrointestinal lymphomas.

To study the characteristics and histogenesis of the malignant lymphomas derived from the gastrointestinal mucosa, histologic and immunohistochemical analyses were performed on a series of 28 malignant lymphomas of the gastrointestinal tract. By cytomorphologic classification, there were two small lymphocytic lymphomas, one small cleaved cell lymphoma, two mixed small cleaved and large cell lymphomas, 17 large cell lymphomas, one small noncleaved cell lymphoma, three immunoblastic lymphomas, and two lymphoblastic lymphomas. This distribution of histologic types was compatible with that of nodal lymphoma. The lymphomas with poor prognostic histology (23 cases) outnumbered those with favorable prognosis (five cases). Three of 28 cases (one in the stomach and two in the small intestine) had cytologic features consistent with centrocytoid cell lymphoma of the mucosa associated lymphoid tissue and were large cell lymphomas. Immunophenotypically, 23 cases expressed B-cell markers (82.1%) and three cases reacted with T-cell markers. Two cases did not react with either T-cell or B-cell markers. True histiocytic lymphomas were not identified. Gastric lymphomas (nine cases) and colorectal lymphomas (three cases) were of B-lymphocyte origin whereas T-cell lymphomas were noted in the small intestine (two cases) and ileocecal region (one case). Three cases of centrocytoid lymphoma were of B-lymphocyte origin. Histologically B-cell lineage lymphomas were evenly distributed on various histologic subtypes but all T-lineage lymphomas belonged to the large cell type. The two cases with undetermined phenotype were lymphoblastic lymphomas histologically. This study showed that the primary GIT lymphomas, mostly of B-cell lineage, were not cytomorphologically distinctive from the nodal lymphomas.(ABSTRACT TRUNCATED AT 250 WORDS)     

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

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

Waldeyer ring lymphomas. A clinicopathological study of 79 cases

Waldeyer ring lymphomas belong to a category of tumours which has not yet been fully defined. Their relation to mucosa-associated lymphoid tissue (MALT) and other extranodal lymphomas remains largely unknown. We performed a clinicopathological retrospective study of 79 patients, and compared them with a series of MALT and nodal lymphomas. Tumours from the nasopharynx and palatine tonsil showed similar histological profiles, with a predominance of large B-cells. Centroblastic lymphomas constituted the largest group ( n = 45), followed by those of centrocytic type (9) with smaller groups of centroblastic-centrocytic (5) and Hodgkin's lymphomas (2). Three monocytoid B-cell lymphomas were identified. Only one case could be classified as MALT lymphoma. The frequency of bcl-2 expression in large B-cell tumours of Waldeyer's ring has an intermediate range between large B-cell lymphomas occurring in mucosal and nodal locations. Epitheliotropism was present in all low-grade cases, and was therefore not a useful marker in the identification of potential MALT lymphomas in contrast with other mucosal sites. Comparative survival studies showed significant overall differences between Waldeyer ring lymphomas, MALT and nodal cases. These disappeared after taking stage and histological grade into account. We conclude that Waldeyer ring lymphomas show distinctive features, mainly in terms of histological distribution and immunophenotype. The key factor determining their behaviour could be their different spreading capability. These findings suggest that extranodal lymphomas are heterogeneous, and indicate the need for additional efforts to clarify this.     

Expression of natural killer cell markers in non-Hodgkin''s lymphomas

One hundred forty-nine cases of non-Hodgkin's lymphoma were studied with a panel of monoclonal antibodies, including antibodies to natural killer (NK) cells--anti-NKH1, anti-Leu 7, and anti-Leu 11b. There were 95 B-cell, 51 T-cell, and three null cell lymphomas. Seventeen T-cell lymphomas (33 per cent) expressed NKH1, Leu 7, and/or Leu 11b. None of the B- or null cell lymphomas expressed the NK markers. In comparison with the NK-negative T-cell lymphomas, the NK-positive cases showed a predilection for the nasal and paranasal region. There was a more significant loss of the T-cell markers T3 (peripheral T cell) and T4 (T-helper cell) in NK-positive lymphomas. The difference was due to a high proportion of nasal/paranasal lymphomas, which were associated with a frequent loss of T-cell markers, among the NK-positive cases. However, a similar degree of loss of T-cell markers was observed among NK-positive and NK-negative nasal/paranasal lymphomas. We conclude that expression of NK markers occurs exclusively in a proportion of T-cell lymphomas, but not B-cell or null cell lymphomas. The reason this occurs predominantly in nasal and paranasal lymphomas is unknown.     

Malignant lymphomas in primates and the principles of their morphological diagnosis (on a baboon model of malignant lymphomas)

114 baboons with non-Hodgkin lymphoma (NHL) were examined, by using the morphoimmunological phenotyping technique. According to the Kiel classification, 14 types of non-Hodgkin lymphomas of high and low malignancy are identified and described. These include 8 T-cell lymphomas and six B-cell NHL. Some morphoimmunological characteristics were found. The morphological cell atypia coincided with the abnormal immunotype of tumor cells. The nosological type of hemoblastosis in the baboons is characterized by the development of mainly malignant lymphomas.     

CD40 ligand is constitutively expressed in a subset of T cell lymphomas and on the microenvironmental reactive T cells of follicular lymphomas and Hodgkin's disease.

Although CD40 has been extensively studied in B- and T-cell non-Hodgkin's lymphomas (NHLs)/leukemias, and more recently in Hodgkin's disease (HD), little is known about the expression of its ligand (CD40L) in lymphoproliferative disorders other than T-cell NHLs/leukemias. A series of 121 lymphoma/leukemia samples, including 35 cases of HD, 34 T-cell and 39 B-cells NHLs, 2 cases of adult T-cell leukemia/lymphoma, and 11 cases of T-cell acute lymphoblastic leukemia, were evaluated for CD40L expression by immunostaining of frozen tissue sections and flow cytometry with the anti-CD40L monoclonal antibody M90. CD40L was constitutively expressed by neoplastic cells in 15 of 36 (42%) T-cell NHLs/adult T-cell leukemia/lymphomas, almost invariably those displaying the CD4+/CD8- phenotype, whereas no CD40L-expressing tumor cells could be found in B-cell NHL and HD. Among T-cell acute lymphoblastic leukemias, CD40L was detected only on 2 cases displaying a stem-cell-like phenotype. In follicular B-cell lymphomas a large number of CD40L-expressing CD3+/CD4+ T lymphocytes were found admixed with tumor cells within the neoplastic follicles and in their surrounding areas. In the nonfollicular B-cell lymphomas, CD40L-positive CD3+/CD4+ T lymphocytes were few or absent. In all HD subtypes other than the nodular lymphocytic predominance, CD40L-expressing CD3+/CD4+ T lymphocytes were numerous in the HD-involved areas and were mainly located in close proximity to the Reed-Sternberg cells. Our data indicate that in human lymphomas CD40L is preferentially expressed by a restricted subset of T-cell lymphomas, mostly with CD4 immunophenotype. Finally, we have provided morphological evidence that CD40L may play an important role in the cell contact-dependent interaction of tumor B-cells (CD40+) within the neoplastic follicles or Reed-Sternberg cells (CD40+) in HD-involved areas and the microenvironmental CD3+/CD4+/CD40L+ T lymphocytes.     

Preferential expression of the mucosal homing receptor integrin alpha 4 beta 7 in gastrointestinal non-Hodgkin's lymphomas.

Recent studies have identified the integrin alpha 4 beta 7 as a mucosal homing receptor that mediates lymphocyte migration to the intestinal mucosa by binding to MAdCAM-1, a vascular recognition molecule (addressin) selectively expressed on mucosal endothelium. In the present study, we have assessed the expression of alpha 4 beta 7 on B- and T-cell non-Hodgkin's lymphomas of different primary localization and on related normal lymphocytes. Among B-lineage lymphomas, expression of alpha 4 beta 7 was present in the majority of cases of malignant lymphomatous polyposis of the intestine and low-grade lymphoma of the mucosa-associated lymphoid tissue/monocytoid B-cell lymphoma and in some cases of precursor B-cell lymphoma. CLL/small lymphocytic lymphoma, (nodal) mantle cell lymphoma, follicular center cell lymphoma, Burkitt's lymphoma, and diffuse large B-cell lymphoma were virtually always alpha 4 beta 7 negative, as was the case when localized in the mucosa-associated lymphoid tissue. The normal B cells of the follicle mantles and part of the B cells of the extrafollicular B-cell compartment of lymphoid tissues expressed moderate levels of alpha 4 beta 7. By contrast, follicular center cells were alpha 4 beta 7 negative. Among T-lineage lymphomas, expression of alpha 4 beta 7 was also strongly related to the primary localization; in mucosal, nodal, and cutaneous T cell lymphomas the percentage of positive cases was 56%, 17%, and 0%, respectively. All cases of precursor T-cell lymphoma were alpha 4 beta 7 negative. High expression of alpha 4 beta 7 was found on a subset of peripheral blood memory T cells as well as on lymphocytes in the intestinal mucosa. We conclude that non-Hodgkin's lymphomas that are related to mucosa-associated B- and T-lymphocyte populations selectively express the mucosal homing receptor alpha 4 beta 7. The presence of this receptor underscores their distinctive character and may play an important role in determining their characteristic mucosal dissemination pattern.     

Primary bony peripheral T-cell lymphoma mimicking nasal type NK/T-cell lymphoma: a case report

Primary bony lymphomas are rare, and nearly all are high-grade B-cell lymphomas. Natural killer (NK)/T-cell lymphomas are highly aggressive lymphomas of NK- or T-cell lineage with predominant extranodal presentation and are divided into nasal and nasal-type (extra-nasal). We report a primary bony peripheral T-cell lymphoma mimicking NK/T-cell lymphoma, nasal type. A 22-year-old Taiwanese male presented with a frontal skull bone mass noted for 3 weeks, and received craniectomy with tumor removal. His tumor showed extensive coagulative necrosis with angioinvasion by large lymphoma cells expressing CD2, CD8, CD16, CD43, CD45, CD45RO, CD56, T-cell intracellular antigen-1, and granzyme B, but not CD3, CD4, CD20, CD57, CD68, and betaF1. In situ hybridization for Epstein-Barr virus-encoded mRNA was negative. Polymerase chain reaction study of formalin-fixed tissue showed clonal rearrangement of the T-cell receptor-gamma chain gene. The diagnosis was peripheral T-cell lymphoma, unspecified subtype. The initial stage was I(EA). His lymphoma was refractory to chemotherapy, and bony metastases developed in the right iliac bone 2 months later. He died of disease after 6 months without autopsy. We emphasize the importance of detailed immunohistochemical and gene rearrangement studies for the classification of malignant lymphomas via a very rare primary bony lymphoma of peripheral T-cell subtype.     

Dipeptidyl aminopeptidase-IV as a histochemical marker of differential diagnosis of large cell anaplastic CD30+-lymphoma and Hodgkin's disease

Using histochemical methods, we studied distribution of dipeptidylaminopeptidase-IV (DPP-IV) in tumor cells of 16 patients with non-Hodgkin's malignant lymphomas (NHL) including B-cell NHL (10 cases), pleomorphic T-cell lymphoma (1 case), CD30+ anaplastic large cell lymphoma (ALCL) of T-cell (1 case) and ALCL of null-cell type (4 cases) and of 13 patients with Hodgkin's disease (HD). The results indicate that tumour cells of pleomorphic T-cell NHL and ALCL of T- and null-cell type showed DPP-IV activity. In contrast, no DPP-IV activity was seen in the tumor cells of B-cell NHL (lymphocytic, centroblastic/centrocytic, centroblastic, immunoblastic), in Berezovsky-Reed-Sternberg and Hodgkin's cells of different HD variants. These results demonstrate that difference in DPP-IV activity between tumor cells of ALCL and HD may be diagnostically important for separation of ALCL from HD and moreover may be used in verification of the borderline between HD-like ALCL and ALCL-like HD. It is possible that DPP-IV activity contributes to pathogenesis of ALCL and may determine clinical behaviour of this NHL being involved in autocrine and paracrine regulation of tumor cell growth of ALCL.     

Sinonasal non-Hodgkin's lymphomas and Wegener's granulomatosis: A clinicopathological study

Summary Reports of sinonasal non-Hodgkin's lymphomas, analysed with monoclonal antibodies, are scarce, and differentiation of these lymphomas from Wegener's granulomatosis can be difficult. In this study, we investigated histopathologically and immunohistologically 20 cases of non-Hodgkin's lymphoma, primary in the sinonasal region, and sinonasal biopsies from 11 patients with Wegener's granulomatosis. All T-cell lymphomas (n=7) and plasmacytomas (n=4) were stage I at clinical presentation, while all B-cell lymphomas (n=9) presented at higher stages. T-cell lymphomas tended to be more frequent in the nasal cavity and paranasal sinuses; B-cell lymphomas more often presented in the nasopharynx. Remarkably, 1 B-cell lymphoma expressed MT1, and 1 T-cell lymphoma expressed L26 (CD 20). The follow-up of 2 patients with a clinical diagnosis of Wegener's granulomatosis was suggestive of non-Hodgkin's lymphoma. Retrospective immunohistochemical analysis revealed that the original histological diagnosis of non-specific inflammation had to be changed to T-cell lymphoma, pleomorphic small cell type. We conclude that a biopsy from the sinonasal region with a dense inflammatory infiltrate, consisting predominantly of Tlymphocytes, renders a diagnosis of Wegener's granulomatosis unlikely and is at least suspicious of T-cell lymphoma. Immunohistochemical analysis is warranted for this type of biopsy.     

Immunohistochemical staining of non-Hodgkin's lymphoma with monoclonal antibodies specific for the leucocyte common antigen

Forty cases of non-Hodgkin's lymphoma (NHL) have been stained with monoclonal antibodies (F8-11-13, F-10-89-4 and Dako LC) to the Leucocyte Common Antigen (LC) in both cryostat and paraffin sections with an immunoperoxidase technique. In cryostat sections all B-cell lymphomas (25/25) reacted with F10-89-4 and Dako LC, whilst the majority (23/25) stained with F8-11-13; of the T-cell lymphomas studied, all reacted with F10-89-4 (6/60 and Dako LC (4/4), however 2/6 did not react with F8-11-13. Similar variability in reaction was observed in malignant histiocytosis where 1/3 did not react with F8-11-13 whilst all three reacted with F10-89-4 and Dako LC. In paraffin sections (using the two MCabs F8-11-13 and Dako LC) three of the 25 B-cell lymphomas failed to stain with either F8-11-13 or Dako LC (one lymphocytic lymphoma and two lymphomas showing plasmacytic differentiation). The remainder of the B-cell lymphomas reacted with both antibodies. Six out of 12 T-cell lymphomas did not stain with either F8-11-13 or Dako LC, using our standard immunoperoxidase procedure. Staining with Dako LC was however detected in all cases of T-cell lymphoma when incubation with primary antibody was extended from thirty minutes (standard) to overnight. This study confirmed that LC can be detected in all NHL in cryostat sections, and that in the majority of B-cell NHL the higher molecular weight component of LC was demonstrable using F8-11-13. Difficulty in detecting LC determinants after tissue processing for paraffin sections in a number of cases of NHL, especially those of T-cell type or showing plasmacytic differentiation, suggests that lack of reaction with these antibodies does not always preclude the diagnosis of lymphoma.     

Radiographic staging procedures and radiotherapy of malignant lymphoma

Radiographic studies play an important role in the clinical staging of malignant lymphoma (ML). Conventional procedures are plain chest X-ray, lymphangiography, gastrointestinal series, and 67Ga scintigraphy. Gastro-intestinal series is essential in non-Hodgkin's lymphoma (NHL) of Waldeyer's ring and thyroid. 67Ga scintigraphy is a non-invasive procedure useful in the screening of ML. Recently marked improvements have been made in the diagnostic modalities. CT scan and NMR have made it very easy to diagnose ML of the central nervous system and detect the extension of tumors at all sites. In some cases with Hodgkin's disease (HD), staging laparotomy is necessary, but not in cases with NHL. If tumors are localized, subtotal or total nodal irradiation is performed for patients with HD, and generous involved field is employed for NHL with or without combined chemotherapy at our department. Good local control is obtained except for NHL of the central nervous system at a total dose of 40-50 Gy. NHL is prone to relapse outside the radiation field. Therefore we consider that combined chemotherapy is indicated for NHL such as T-cell lymphomas, those with high grade histology classified according to the Working Formulation, and with involvement of lymph nodes larger than 6 cm in diameter.