Absence of bcl-2 major breakpoint region and JH gene rearrangement in lymphocyte predominance Hodgkin's disease. Results of Southern blot analysis and polymerase chain reaction

Recent evidence suggests that nodular lymphocyte predominance Hodgkin's disease (NLPHD) is a distinct entity that may be related to progressively transformed germinal centers, abnormal B-lymphoid hyperplasia, and low-grade B-cell lymphoma. bcl-2 is a marker for the translocation t(14;18)(q32;q21), which occurs in most follicular-derived B-cell lymphomas. Eleven cases of NLPHD and 19 cases of Hodgkin's disease of nodular sclerosis (NSHD) and mixed cellularity (MCHD) type were analyzed for immunoglobulin JH gene rearrangement. bcl-2 translocation was determined with Southern blot analysis and the polymerase chain reaction using biotin labeled probes to the major breakpoint region and the alkaline phosphatase reaction. All cases of NLPHD were negative for JH gene rearrangement and bcl-2 translocation. Cases of NSHD and MCHD were similarly negative for bcl-2, although three cases exhibited clonal JH gene rearrangements. These results confirm that a clonal B-cell population is not detected in NLPHD. Cases of NLPHD differ from most low-grade follicular B-cell lymphomas in that they lack bcl-2 gene rearrangement and t(14;18) translocation at the major breakpoint region.

Specific phenotyping of T-cell proliferations in formalin-fixed paraffin-embedded tissues. Use of antibodies to the T-cell receptor beta F1

Antibody beta F1 to a common framework determinant of the beta subunit of the T-cell receptor (TCR) was used as a specific phenotypic marker for T-cell differentiation in malignant lymphomas. Sensitivity of immunoperoxidase staining in paraffin sections was enhanced by pronase pretreatment, overnight incubation of primary antibody in Tween 20, and use of streptavidin horseradish peroxidase complexes to amplify the reaction. All 43 cases of B-cell lymphoma were negative for TCR. Reed Sternberg (RS) cells in 3 of 20 cases of Hodgkin's disease exhibited cell membrane staining for TCR (all nodular sclerosis type), further evidence that some RS cells may be T-cell derived. Twenty-nine of 44 cases of T-cell lymphoma expressed TCR (66%). These included 11 of 12 cases of peripheral T-cell lymphoma (PTCL) of small and mixed cell type, 8 of 9 cases of lymphoepithelioid cell (Lennert's) lymphoma, and 2 of 4 cases of T-cell lymphoblastic lymphoma. Loss of immunoreactivity for TCR occurred in lymphomas of large or activated T-cell type, including 7 of 9 cases of T-cell immunoblastic lymphoma and 3 of 4 cases of large cell PTCL. Antibody beta F1 is a specific and relatively sensitive marker of T-cell phenotype in formalin-fixed paraffin sections of malignant lymphomas.

Peripheral/post-thymic T-cell lymphomas: a spectrum of disease. Clinical, pathologic, and immunologic features of 78 cases

The clinical, pathologic, and immunologic features of 78 cases of peripheral/post-thymic T-cell lymphomas are described. These neoplasms were extremely heterogeneous and were classified as small lymphocytic, mixed small and large cell, large cell, lymphoepithelioid cell, angiocentric, and adult T-cell leukemia/lymphoma type. Some cases revealed angioimmunoblastic or Hodgkin's-like features. These neoplasms mainly affected older adults (mean age, 57 years; median age, 60 years). Lymphadenopathy represented the most frequent clinical presentation, although most patients demonstrated both nodal (87%) and extranodal involvement (77%) during the course of disease. Sites of extranodal disease included skin/soft tissue, spleen, lung, liver, bone, gastrointestinal tract, central nervous system, peripheral blood, nasopharynx, and retrovaginal tissue. Splenomegaly at presentation was most frequently observed in lymphoepithelioid cell lymphomas. Angiocentric lymphomas involved lung. A mediastinal presentation was typically observed in young adults and associated with a poor prognosis. Patients with gastrointestinal lymphomas presented with bleeding and/or malabsorption. B symptoms were present in most cases (65%). Hypercalcemia occurred in four patients. Phenotypic studies of T-cell antigens demonstrated the loss of one or more pan-T-cell markers in eight of 47 cases evaluated. Assessment of T-cell subsets revealed a helper/inducer phenotype for nearly all immunoreactive cases. For the overall series, 32 patients died of disease (median survival time, 11.5 mo). There was a statistical difference between the combined groups of small lymphocytic and lymphoepithelioid cell types as compared with mixed and large cell types, with a poorer survival for the latter group. Angiocentric and adult T-cell leukemia/lymphoma were associated with poor survival. This series of T-cell lymphomas further documents the marked heterogeneity of this group of neoplasms as well as the poor prognosis observed for certain histologic types.

ME1. A monoclonal antibody that distinguishes epithelial-type malignant mesothelioma from pulmonary adenocarcinoma and extrapulmonary malignancies

ME1 is a monoclonal antibody reactive in frozen tissue sections with normal mesothelial cells and malignant mesotheliomas. In this immunoperoxidase study, ME1 reacted with all 40 epithelial type malignant mesotheliomas. Fifty percent or more of the mesothelioma cells were stained in all cases and the staining intensity was strong in 32 and moderate in eight. In contrast, all 19 well- and moderately differentiated pulmonary adenocarcinomas were completely negative, and of the total 88 non-mesotheliomatous malignancies studied, staining comparable to the mesotheliomas was seen in only 6 tumors (2 pulmonary adenocarcinomas, 2 adenocarcinomas of the breast, 1 adenocarcinoma of the pancreas, and 1 melanoma), although limited, weaker staining was seen in additional cases. Five of the six strongly to moderately positive nonmesotheliomatous tumors had immunoreactivity for complementary immunoreactants (CEA, Leu-M1, S-100 protein, HMB-45). Our results with ME1, the first monoclonal antibody that recognizes malignant mesothelial cells, provides a basis for using this reagent in the differential diagnosis of tumors of the pleura and peritoneum.

The m-BACOD combination chemotherapy regimen in large-cell lymphoma: analysis of the completed trial and comparison with the M-BACOD regimen

One hundred thirty-four assessable patients with stage II-IV large-cell lymphoma (LCL) were treated with the combination chemotherapy regimen methotrexate with leucovorin, bleomycin, doxorubicin, cyclophosphamide, vincristine, and dexamethasone (m-BACOD) between July 1981 and May 1986. The m-BACOD regimen substituted moderate-dose methotrexate (200 mg/m2 x 2) for the high-dose methotrexate used in the preceding M-BACOD regimen; all other drugs were administered as with m-BACOD. Eighty-two patients (61%) in the completed m-BACOD trial achieved a complete response (CR). With a median follow-up of 3.6 years, 62 patients (76%) continue in CR. Predicted survivals of 1, 3, and 5 years for the entire m-BACOD group are 80%, 63%, and 60%, respectively, with a 5-year disease-free survival (DFS) of 74% for the patients who achieve CR. The results obtained with m-BACOD are comparable with those obtained in the preceding M-BACOD trial, which now has a median follow-up of 8.0 years. The reduction in methotrexate dosage in m-BACOD patients was not associated with an increased incidence of CNS relapse. Long-term follow-up of the 215 M/m-BACOD patients indicates that the regimens are not associated with an increased incidence of secondary malignancy. Prolonged follow-up also indicates that advanced-stage patients have a persistent rate of late relapse of about 7.0% per year for years 2 to 5 of their follow-up and that stage II patients have an approximate 2.1% per year rate of late relapse. Application of the previously described prognostic factor model to the 215 M/m-BACOD patients from the completed trials identifies a high-risk group of patients with a CR rate and predicted 5-year survival (38% and 24%, respectively) that are significantly worse than those of the group as a whole (65% and 57%, respectively).

Leu-22: a preferential marker for T-lymphocytes in paraffin sections. Staining profile in T- and B-cell lymphomas, Hodgkin's disease, other lymphoproliferative disorders, myeloproliferative diseases, and various neoplastic processes

Monoclonal antibody Leu-22 represents an effective reagent for detection of neoplastic and nonneoplastic T-cells in paraffin sections of routinely processed tissues (242 specimens evaluated). In nonneoplastic tissues, immunoreactivity was localized mainly to lymphoid cells corresponding to a T-cell distribution. Immunoreactivity in lymphoid neoplasms, however, was preferentially, but not exclusively, limited to T-cell populations. Fifty-four of 60 T-cell neoplasms (90%) of various histologic types were Leu-22 positive. The pattern of immunoreactivity consisted mainly of membrane staining, with focal weak cytoplasmic positivity. Twenty-five of 67 B-cell neoplasms (37%) were also Leu-22 positive, with low-grade lymphomas (well/moderately well-differentiated lymphocytic types) representing most immunoreactive cases. In Hodgkin's disease, although most small lymphoid cells were Leu-22 positive, only rare Reed-Sternberg cells were immunoreactive. In all cases, histiocytes and myeloid cells exhibited variable immunoreactivity. The epitope identified by Leu-22 was detectable in formalin- and B5-fixed tissues but apparently was denatured after fixation in Zenker's-acetic acid solution used for bone marrow biopsies. Evaluation of a wide variety of nonhematopoietic neoplasms (64 total) revealed diffuse cytoplasmic staining in a few cases. However, membrane staining, typically noted for lymphoid cells, was not observed. Leu-22 potentially represents a useful marker for lymphoid cells, preferentially of T-cell origin, with optimal applicability as part of a panel that includes an effective pan-B-cell marker.

Rheumatoid aortitis: a rarely recognized but clinically significant entity

Aortitis as a feature of rheumatoid arthritis is considered rare. We have, however, identified 10 patients with aortitis from among 188 consecutive autopsy cases of rheumatoid arthritis. There were 5 men and 5 women with a mean duration of rheumatoid arthritis of 9.6 years. Nine were rheumatoid factor positive and had associated nodules. In addition to standard treatment regimens, 9 patients received corticosteroids. Although involvement of the thoracic aorta was most common, involvement of both the thoracic and abdominal aorta was present in 4 cases. Two patients had aneurysmal dilatation of the thoracic aorta and 1 of the abdominal aorta. Microscopic features of aortitis included necrosis of medial smooth muscle and elastica, with an inflammatory infiltrate comprising primarily lymphocytes and plasma cells. A panmural aortitis was seen in 3 cases. Rheumatoid granulomas were noted in the aortic wall in 5. The diagnosis of aortitis was not made until autopsy in any case. Aortitis was hemodynamically significant in 3 patients. Two had congestive heart failure secondary to thoracic aortitis and aortic valvulitis, and 1 had rupture of an abdominal aortic aneurysm at a site involved by aortitis. Seven patients had rheumatoid vasculitis with a mean of 10 organs involved. Six of these died of complications directly related to vasculitis, including 4 patients with coronary arteritis and associated myocardial infarction. Aortitis can be a feature of severe rheumatoid arthritis and is often associated with rheumatoid vasculitis. Hemodynamic compromise does occur and may be fatal.

Hodgkin's disease, lymphocyte predominance type, nodular--further evidence for a B cell derivation. L & H variants of Reed-Sternberg cells express L26, a pan B cell marker

Immunoreactivity for L26, a highly effective pan B cell marker that can be detected in paraffin sections, was evaluated in 72 cases of Hodgkin's disease of various histologic types. In all cases of nodular lymphocyte predominance type of Hodgkin's disease, L & H variants of Reed-Sternberg cells uniformly exhibited strong immunoreactivity for L26. Other variants of Reed-Sternberg cells, eg, lacunar, mononuclear, and diagnostic forms, present in nodular sclerosis, mixed cellularity, and lymphocyte depletion types of Hodgkin's disease, infrequently expressed L26 reactivity. In 55 of 63 cases (87%) of these combined types, less than 5% of Reed-Sternberg cells or variants were L26 positive. In the remaining cases, a larger proportion of these cells expressed L26. Topographic patterns of immunoreactivity for small lymphocytes in these different types of Hodgkin's disease also varied. In nodular lymphocyte predominance type, L26 positive lymphocytes (presumptive B cells) were mainly localized to nodular areas of the proliferation. In other types of Hodgkin's disease, L26 positive cells occurred in small or large aggregates and generally represented a minor proportion of the population of lymphoid cells. These studies further support a B cell derivation for L & H variants of Reed-Sternberg cells and provide additional evidence that nodular lymphocyte predominance type Hodgkin's disease may represent a distinct entity, possibly an unusual low grade B cell lymphoma. These data also suggest that some Reed-Sternberg cells and variants present in other histologic types of Hodgkin's disease may be of B cell derivation, and precludes the use of L26 as a diagnostic discriminant in cases in which the distinction between Hodgkin's disease and non-Hodgkin's lymphoma is unclear.

Silicone lymphadenopathy in a long distance runner: complication of a silastic prosthesis

A 33-year-old male runner, who had undergone a Swanson silastic prosthetic implant for degenerative joint disease of the first metatarsal head and proximal phalanx of the right great toe, presented with unilateral inguinal lymphadenopathy. Biopsy revealed confluent, non-caseating granulomas containing silastic material. Silicone lymphadenopathy is unusual and most frequently presents as axillary adenopathy in patients with rheumatoid arthritis as a sequelae of prosthetic surgery. This case is clinically distinctive for its site of presentation in a healthy athlete and is histologically remarkable for the marked granulomatous response to the silastic elastomers.

Circulating malignant cells in non-Hodgkin's lymphoma: correlation with binding by peanut agglutinin

A significant number of patients with non-Hodgkin's lymphoma have peripheral blood involvement during the course of their disease. Because the expression of receptor for the lectin peanut agglutinin PNA by normal lymphocytes is associated with noncirculating (stationary phase) cells, we studied the relationship between PNA binding by lymphoma cells and the presence of clonal B cells in the blood of 38 patients with B-cell lymphoma. The binding of PNA by cells in tissues was determined by the immunoperoxidase method and by two-color flow cytometry. Circulating lymphoma cells (clonal B cells) were identified by a sensitive flow-cytometric technique (kappa-lambda analysis) and were also studied for PNA binding in some cases. In all, 16 of 38 (42%) of lymphomas were PNA+, including a spectrum of histologic types. Circulating lymphoma cells were demonstrated in 17 of 22 PNA-lymphomas, whereas only 3 of 16 of PNA+ lymphomas had such circulating cells. Thus, there is a significant association between PNA binding and peripheral blood involvement by lymphoma (P less than .005 by chi-square analysis). In 12 cases, the circulating and tissue lymphoma cells had similar expression of PNA receptor (2 PNA+ and 10 PNA- cases), indicating that modulation of the PNA binding sites did not occur. In three patients who presented with lymphosarcoma cell leukemia, the circulating malignant cells were PNA-. These findings suggest that for both normal and malignant lymphocytes the absence of binding sites for PNA is associated with the capacity of these cells to circulate freely.

S-100 immunoreactivity in primary and metastatic carcinoma of the breast: a potential source of error in immunodiagnosis

Immunoreactivity for S-100 protein, typically a marker for malignant melanoma and neural-derived tumors, was observed in neoplastic cells of 57 of 68 cases (84%) of formalin-fixed, paraffin-embedded primary and/or metastatic carcinoma of the breast of various histologic types. The extent of S-100 immunoreactivity varied, with only a minor proportion of positive tumor cells noted in some cases. An awareness of this staining profile for S-100 protein, particularly in metastatic poorly differentiated neoplasms with unknown primaries, is imperative for accurate immunohistochemical interpretation. Using a panel of reagents which includes antibodies to keratin proteins and epithelial membrane antigen, the epithelial nature of S-100-positive carcinomas may be readily defined. Tumor cells in all cases of primary and metastatic carcinoma of the breast evaluated in this study exhibited strong staining for both of these tissue markers. To preclude misinterpretation of tumor type due to anomalous staining patterns for a specific antibody, eg, S-100 protein, a panel of antibodies is recommended for assessment of metastatic poorly differentiated tumors.

Immunohistochemical staining for terminal deoxynucleotidyl transferase (TDT). An enhanced method in routinely processed formalin-fixed tissue sections

This report describes an improved technique for sensitive and specific localization of terminal deoxynucleotidyl transferase (TdT) in routinely processed paraffin-embedded, formalin-fixed tissue sections using DNAse pretreatment and the avidin-biotin complex (ABC) technique. This method is useful in identifying lymphoblastic lymphomas (14/15 cases positive), with all other B- and T-cell lymphomas tested negative for the reaction. Used in conjunction with monoclonal antibodies immunoreactive for T- and B-cells in paraffin sections this technique should prove helpful in immunophenotyping malignant lymphomas where fresh tissue is unavailable for study.

Keratin protein immunoreactivity of sarcomatoid and mixed types of diffuse malignant mesothelioma: an immunoperoxidase study of 30 cases

To define the role of keratin protein immunohistochemistry in the pathologic diagnosis of the sarcomatoid type of diffuse malignant mesothelioma (DMM), we examined 30 DMM (16 pure sarcomatoid type and 14 mixed sarcomatoid-epithelial type) by an indirect immunoperoxidase technique using three commercially available antibodies to keratin proteins. The sarcomatoid (spindle-cell) areas of all 30 cases of sarcomatoid DMM were immunoreactive for keratin proteins. In 14 of 16 cases of sarcomatoid DMM, 50% or more of the tumor cells were reactive with one or more antibodies; however, polyclonal bovine muzzle and monoclonal AE1/AE3 antibodies were distinctly superior to polyclonal human callus keratin antibody in the detection of spindle tumor cells. In contrast with the staining patterns observed for DMM, 39 spindle-cell malignancies and tumor-like processes of 10 histogenetic types were unreactive with the three antibodies. Those spindle-cell tumors and reactive mesothelial proliferations that may enter into the differential diagnosis of sarcomatoid DMM are discussed. We conclude that keratin protein immunohistochemistry is a sensitive and highly useful method for the pathologic diagnosis of the sarcomatoid type of DMM and its distinction from other spindle-cell neoplasms.

Ultrastructural localization of Leu M1 in Reed-Sternberg cells and normal myeloid cells

An antigen Leu M1 has been localized to myelomonocytic cells and Reed-Sternberg cells by light microscopic immunocytochemical studies. We used both pre- and post-embedding immunoelectron microscopy to define the ultrastructural distribution of this antigen. Post-embedding techniques heavily labeled the granules of polymorphonuclear leukocytes and the nonspecific granules of eosinophils. At high concentrations there was labeling of the specific granules of the eosinophil. The antibody consistently labeled the perinuclear granules and vesicles of Reed-Sternberg cells. Some Reed-Sternberg cells also exhibited labeling of the endoplasmic reticulum, suggesting that these cells have the capacity to synthesize this antigen. Although plasma membranes were labeled with the post-embedding technique, these structures were most heavily labeled with the pre-embedding method. These results indicate that Leu M1 is synthesized and packaged by Reed-Sternberg cells and represents an integral structural component of these cells.

Tonsillar epithelial dendritic cells. Demonstration by lectin binding, immunohistochemical characterization, and ultrastructure

The association of tonsillar epithelium with lymphoid tissue suggests a functional relationship in the generation of local immune responses analogous to skin. Therefore, we investigated this epithelium for the presence of dendritic cells similar to epidermal Langerhans cells. Clusters of tonsillar epithelial dendritic cells (TEDC) were revealed by binding of the lectin peanut agglutinin, a feature not previously directly demonstrated for this cell type. Similar to epidermal Langerhans cells, TEDC showed immunoreactivity for antibodies to S-100, T6, and Ia antigens. Ultrastructurally, TEDC had features most similar to epidermal indeterminate cells. In addition, the tonsillar epithelium showed regional variation in the types of intraepithelial lymphocytes present. Surface epithelium contained T cells predominantly of helper/inducer phenotype, while the crypt epithelium contained a mixture of B cells, plasma cells, and T cells of both helper/inducer and suppressor/cytotoxic phenotypes. These findings, together with the demonstration of TEDC, suggest that the tonsillar epithelial microenvironment, like skin, provides a site of cell-cell interactions important in initiating immune responses.

The m-BACOD combination chemotherapy regimen in the treatment of diffuse large cell lymphoma

The m-BACOD regimen attempted to lower the dose of methotrexate in the M-BACOD (methotrexate, bleomycin, doxorubicin, cyclophosphamide, vincristine, dexamethasone) program. Between July 1981 and January 1985, 87 previously untreated or minimally treated patients with diffuse large cell lymphoma were treated with the m-BACOD regimen (methotrexate 200 mg/m2 on days 8 and 15, bleomycin 4.0 mg/m2 on day 1, doxorubicin 45 mg/m2 on day 1, cyclophosphamide 600 mg/m2 on day 1, vincristine 1.0 mg/m2 on day 1, and dexamethasone 6 mg/m2 on days 1 to 5; leucovorin was given 24 hours after methotrexate at 10 mg/m2 every six hours for eight doses orally). Of 86 evaluable patients, 59 (68.5%) had a complete remission (CR). Partial response was seen in 21 patients with six still surviving (5 to over 15 months). Of the seven patients who had no change, all have died. The median duration of follow-up for the entire series was 30 months (range, 2 to 61). Relapse from CR occurred in 15 of 59 (25%). Currently, 56 of 87 patients (64%) survive; all but 12 are in their first remission. Overall survival was 84% for those achieving an apparent CR. The major toxic effect of the m-BACOD regimen was myelosuppression with severe leukopenia and fever, which required hospitalization for about 33% of patients. Mucositis occurred in 39 patients; 19 had severe mucositis. No significant difference in overall survival was seen between the high-dose methotrexate M-BACOD and the low-dose m-BACOD regimens.

The distinction of adenocarcinoma from malignant mesothelioma in cell blocks of effusions: the role of routine mucin histochemistry and immunohistochemical assessment of carcinoembryonic antigen, keratin proteins, epithelial membrane antigen, and milk fat globule-derived antigen

The immunohistochemical profile (i.e., carcinoembryonic antigen, keratin proteins, epithelial membrane antigen, human milk fat globule-derived antigen, and mucin) of paraffin-embedded cell blocks of 20 malignant effusions from patients with malignant mesothelioma was compared with that of 39 malignant effusions from patients with metastatic adenocarcinoma to determine whether these markers distinguished between these tumor types. Twenty-three adenocarcinomas (59 per cent) stained for mucin. Immunoreactivity for carcinoembryonic antigen (CEA) was observed in 28 adenocarcinomas (72 per cent). All were immunoreactive for keratin proteins, and 29 adenocarcinomas (74 per cent), including seven that were mucin and CEA negative and exhibited a "peripheral predominant" staining pattern for keratin proteins. By contrast, none of the mesotheliomas stained for mucin or for CEA, and, although all were immunoreactive for keratin proteins, none demonstrated a peripheral predominant pattern of staining. Epithelial membrane antigen and milk fat globule-derived antigen were identified in the majority of both mesotheliomas and adenocarcinomas. Neither staining intensity nor pattern of reactivity of these markers clearly distinguished the tumors. This study of cell blocks of serous effusions suggests that staining for mucin, immunoreactivity for carcinoembryonic antigen, and a peripheral predominant pattern of reactivity for keratin proteins represent highly characteristic markers of adenocarcinomas, which identify the majority of these tumors (38 of 39) and allow their distinction from malignant mesotheliomas.

The human lymph node germinal center cell: characterization and isolation by using two-color flow cytometry

The germinal center of lymphoid tissues is a critical microenvironmental site of B cell activation and differentiation in response to antigenic stimuli. However, characterization of germinal center cells (GCC) in tissue sections has proved technically difficult. Therefore, we have employed two-color flow cytometric analysis of suspended human tonsillar lymphocytes in order to define more precisely the immunologic features of GCC. These cells were identified in suspension by virtue of their specific surface binding of the lectin peanut agglutinin (PNA), confirmed by tissue immunoperoxidase studies. Phycoerythrin-labeled lectin was used in combination with a variety of fluorescein-labeled antibodies in order to identify subpopulations of tonsillar lymphocytes. The majority of PNA+ cells were B cells, and both PNA+ and PNA- B cells stained for surface immunoglobulin light chains. PNA+ cells lacked surface IgD, but included cells with surface IgG and IgM. Both PNA+ and PNA- cells stained for B1, B2, BA-1, Leu-12, Leu-14, CR-I, and HLA-DR antigens, whereas CALLA was present only on PNA+ cells. There were differences between PNA+ and PNA- cells in the relative expression of B1 and B2 antigens, possibly reflecting differences in B cell activation or maturation. A small proportion of T cells were PNA+, including both helper/inducer and suppressor/cytotoxic phenotypes. PNA+ cells included both small and large lymphoid cells, and almost all DNA synthetic activity was associated with the large PNA+ cells. PNA+ B cells isolated by cell sorting had morphologic features characteristic of GCC. Therefore, PNA+ cells in suspension appeared to represent GCC, and features of these cells that cannot be convincingly shown in tissue section studies were demonstrated by flow cytometry.

The human lymph node germinal center cell: characterization and isolation by using two-color flow cytometry

The germinal center of lymphoid tissues is a critical microenvironmental site of B cell activation and differentiation in response to antigenic stimuli. However, characterization of germinal center cells (GCC) in tissue sections has proved technically difficult. Therefore, we have employed two-color flow cytometric analysis of suspended human tonsillar lymphocytes in order to define more precisely the immunologic features of GCC. These cells were identified in suspension by virtue of their specific surface binding of the lectin peanut agglutinin (PNA), confirmed by tissue immunoperoxidase studies. Phycoerythrin-labeled lectin was used in combination with a variety of fluorescein-labeled antibodies in order to identify subpopulations of tonsillar lymphocytes. The majority of PNA+ cells were B cells, and both PNA+ and PNA- B cells stained for surface immunoglobulin light chains. PNA+ cells lacked surface IgD, but included cells with surface IgG and IgM. Both PNA+ and PNA- cells stained for B1, B2, BA-1, Leu-12, Leu-14, CR-I, and HLA-DR antigens, whereas CALLA was present only on PNA+ cells. There were differences between PNA+ and PNA- cells in the relative expression of B1 and B2 antigens, possibly reflecting differences in B cell activation or maturation. A small proportion of T cells were PNA+, including both helper/inducer and suppressor/cytotoxic phenotypes. PNA+ cells included both small and large lymphoid cells, and almost all DNA synthetic activity was associated with the large PNA+ cells. PNA+ B cells isolated by cell sorting had morphologic features characteristic of GCC. Therefore, PNA+ cells in suspension appeared to represent GCC, and features of these cells that cannot be convincingly shown in tissue section studies were demonstrated by flow cytometry.

Non-Hodgkin's lymphoma, multilobated B-cell type: report of nine cases with immunohistochemical and immunoultrastructural evidence for a follicular center cell derivation

The clinical, pathologic, and immunologic features in nine cases of non-Hodgkin's lymphoma of the multilobated B-cell type are described. Clinical and phenotypic heterogeneity was observed in these B-cell neoplasms. A probable follicular center cell derivation for these cytologically unusual B-cell lymphomas is supported by antecedent histories of follicular center cell neoplasms in three cases; a focal nodular pattern in one case; the demonstration of peanut lectin (PNA) receptors, a marker for follicular center cells, on neoplastic multilobated B cells; and immunoultrastructural studies of nonneoplastic tonsillar cells that identified and characterized rare multilobated cells, immunoreactive for B1, B2, and Ia membrane antigens, a phenotype consistent with follicular center-type cells. Comparison of B- and T-cell multilobated lymphomas revealed that only immunologic studies accurately discriminated between these neoplasms.

Identification of major prognostic subgroups of patients with large-cell lymphoma treated with m-BACOD or M-BACOD

One hundred twenty-one patients with diffuse large-cell lymphoma treated with m- or M-BACOD (methotrexate, bleomycin, doxorubicin, cyclophosphamide, vincristine, and dexamethasone) were evaluated for pretreatment characteristics predictive for response and survival. Two characteristics, poor performance status and massive bulky disease, were negatively associated with response rate in a multivariate analysis. These two characteristics were also negatively associated with survival in multivariate analysis, as was another factor, an increased number of extranodal sites of disease. These three pretreatment characteristics were used to construct a model containing 12 categories of patients at increasing risk for relapse and shortened survival. These categories divided naturally into three broad groups of patients with respective 5-year survival rates of 68%, 55%, and 24%.

Immunohistochemical localization of smooth muscle myosin in human spleen, lymph node, and other lymphoid tissues. Unique staining patterns in splenic white pulp and sinuses, lymphoid follicles, and certain vasculature, with ultrastructural correlations

The anatomic distribution of smooth muscle myosin, a contractile protein, was determined in a variety of lymphoid tissues (spleen, lymph nodes, tonsils) with the use of highly specific rabbit antibodies to human uterine smooth muscle myosin and an indirect immunoperoxidase technique. In the spleen, in addition to the anticipated immunoreactivity in the walls of arteries, veins, splenic capsule, and trabeculas, other staining patterns were observed. Smooth muscle myosin-containing cells which comprised the adventitia of the trabecular arteries appeared continuous with myosin-containing reticular cells of the white pulp. The latter cells assumed a circumferential pattern within the periarteriolar lymphoid sheaths, then blended delicately with the red pulp at the marginal zone. Ultrastructurally, immunogold techniques demonstrated that smooth muscle myosin in these cells was localized to cytoplasmic filaments. Within the red pulp, a different and distinct staining pattern was observed for the splenic sinuses. Short, regular, orderly, and repetitive bands of immunoreactivity, aligned parallel to the long axis of the sinus, extended between contiguous ring fibers. By immunoelectron microscopy these structures corresponded to distinct bundles of filaments in the endothelial lining cells of the splenic sinuses. Factor VIII associated antigen was also identified in the splenic lining cells in cryostat and paraffin sections, and ultrastructurally. Within the red pulp of the spleen, the sheaths of sheathed capillaries also revealed strong immunoreactivity for smooth muscle myosin. Other sites of immunohistochemical localization of smooth muscle myosin included dendritic reticulum cells present in reactive follicles and in nodular non-Hodgkin's lymphomas. Certain vascular structures, specifically sinus lining cells and Schweigger-Seidel capillary sheaths of the spleen and postcapillary venules of lymph nodes and tonsils, coexpressed smooth muscle myosin and Factor VIII associated antigen. The patterns of localization of smooth muscle myosin are correlated with anatomic structures and possible tissue functions.

Immunoultrastructural and morphometric analysis of B lymphocytes in human germinal centers. Evidence for alternate pathways of follicular transformation

Monoclonal antibodies to B-cell differentiation antigens B1, B2, C3b, and Ia were used for ultrastructural characterization of B lymphocytes undergoing follicular transformation in human germinal centers. Morphologic alterations and morphometric parameters including form factor (FF) and nuclear contour index (NCI) were evaluated. Antibodies to B1, Ia, and C3b revealed uninterrupted linear surface membrane staining in B cells at various stages of transformation, while staining for B2 appeared as aggregates of gold particles localized to sites of antigen expression along the cell membrane. B cells with highly irregular or convoluted nuclei (NCI greater than 6.5) formed 3% of follicular lymphocytes and may explain the derivation of rare follicular center cell lymphomas with marked nuclear irregularity which mimic T-cell lymphomas histologically. Cleaved cells (NCI greater than or equal to 4.5) comprised 48% of the cellular population and were present at all stages of transformation. Results of morphometric studies suggest that small cleaved cells (centrocytes) and noncleaved cells transform to large lymphoid cells (centroblasts) along parallel lines, and without following the sequential differentiation pathway suggested by Lukes and Collins.

Immuno-ultrastructural localization of B-cell-specific monoclonal antibodies B1 and B2

Monoclonal antibodies B1 and B2 are thought to recognize B-lineage restricted antigens, and have been used to define stages of B-cell maturation and characterize B-cell lymphomas. Immunostaining on cryostat sections has revealed a puzzling dendritic or extracellular pattern of staining for B2 within germinal centers and neoplastic follicles. In this study B1 and B2 are localized precisely on hyperplastic and neoplastic lymphoid tissues using immuno-ultrastructural techniques on cryostat sections, cell suspensions, and cell monolayers. B1 and B2 were localized to cell surfaces, including microvillous surface projections, on small and large transformed normal and neoplastic B lymphocytes. B2, in addition to staining in lymphoid cells, was localized to anastomosing cytoplasmic processes of dendritic histiocytes. These findings explain the apparently extracellular localization of B2 in cryostat sections and indicate that patterns of staining for B2 may represent a combination of staining on lymphoid cells and dendritic histiocytes.

Multiple phenotypes of prostatic glandular cells in castrated dogs after individual or combined treatment with androgen and estrogen. Morphometric, ultrastructural, and cytochemical distinctions

To demonstrate a potential for multidirectional differentiation in mature prostatic epithelium, 17 beta-estradiol 17-cyclopentylpropionate (ECP) and 5 alpha-androstane-3 alpha, 17 beta-diol dipropionate (3 alpha-diol DP) were administered individually and in combination to castrated dogs. Quantitative ultrastructural and cytochemical methods were used to distinguish phenotypes of glandular cells in the various hormonal environments. Castration-induced glandular cell regression was accompanied by an increased nuclear to cytoplasmic ratio; by enhanced keratin positivity, expressed as dispersed immunolabeled tonofilaments; and by an absence of peanut agglutinin (PNA) binding sites on luminal membranes. Administration of ECP resulted in squamous metaplasia as well as hypertrophy of the glandular epithelium. The hypertrophied estrogen-modified glandular (EMG) cells were characterized by a new population of small (0.29 micron in diameter) secretory granules, bundles of tonofilaments, and PNA-positive luminal membranes. Treatment of castrated dogs with 3 alpha-diol DP produced a greater epithelial hypertrophy than ECP. These cells were characterized by larger (0.49 micron in diameter) secretory granules, dispersed tonofilaments, and no detectable PNA receptors. Joint administration of ECP and 3 alpha-diol DP caused a florid response including squamous metaplasia and hypertrophy of the glandular epithelium which was associated with the emergence of a novel phenotype in androgen-estrogen modified glandular (A-EMG) cells. In A-EMG cells, secretory granules were similar in size to those found in 3 alpha-diol DP-dominated epithelium whereas tonofilaments often appeared in bundles and luminal membranes were PNA positive, i.e., features found in EMG cells. Our results indicate that atrophic canine prostatic glandular cells possess pluripotentiality of response to sex hormones.

Leu-M1 immunoreactivity in nonhematopoietic neoplasms and myeloproliferative disorders. An immunoperoxidase study of paraffin sections

Leu-M1 is a differentiation antigen present on human myelomonocytic cells, which also has been identified in Reed-Sternberg cells and variants of Hodgkin's disease. This study further defines the tissue distribution of Leu-M1, with immunoreactivity observed for neoplastic cells in 14 of 28 formalin-fixed, paraffin-embedded nonhematopoietic neoplasms. With the use of monoclonal antibodies and an indirect immunoperoxidase technic, Leu-M1 was detected in adenocarcinomas of various sites (breast, lung, colon, thyroid, pancreas, and stomach), in squamous cell and transitional cell carcinomas, and in a small-cell anaplastic carcinoma. Evaluation of a wide variety of myeloproliferative disorders indicated that Leu-M1 effectively characterized mature and immature monocytic cells and myeloid cells at late stages of granulopoiesis, but it was not a reliable marker for early myeloid cells including blasts. Leu-M1 monoclonal antibodies are a useful diagnostic reagent, particularly in the assessment of lymphoproliferative disorders, but must be used with extreme caution and full awareness of its staining profile.

Are keratin proteins a better tumor marker than epithelial membrane antigen? A comparative immunohistochemical study of various paraffin-embedded neoplasms using monoclonal and polyclonal antibodies

Epithelial membrane antigen and keratin proteins represent markers of epithelial differentiation that may be detected in routine formalin-fixed, paraffin-embedded tissues. Eighty-seven neoplasms, including 48 adenocarcinomas of various types, squamous and transitional cell carcinomas, small-cell anaplastic carcinomas, carcinoid tumors, mesotheliomas, hepatomas, melanomas (metastatic), adrenal cortical carcinomas, germ cell tumors, and extramammary Paget's disease, were assessed to determine the relative effectiveness of these antigens as tumor markers. Immunoperoxidase studies were performed using monoclonal antibodies to epithelial membrane antigen and monoclonal (combined AE1 and AE3) and polyclonal (bovine muzzle keratins) antibodies to keratin proteins. In more than half the cases (50/87%), both markers yielded comparable results. However, in 29 cases (33%), keratin proteins were clearly superior to epithelial membrane antigen as a tumor cell marker. Particular discrepancies were apparent for some gastrointestinal adenocarcinomas, squamous cell carcinomas, hepatomas (hepatocellular type), spindle cell components of mesotheliomas, and carcinoid tumors. Epithelial membrane antigen represented a better marker in eight cases (9%), mainly for small-cell anaplastic carcinomas and some renal cell and pulmonary adenocarcinomas. Adrenal cortical carcinomas, melanomas, and seminomas were nonimmunoreactive for both antigens. Epithelial membrane antigen and keratin proteins represent useful complementary markers in diagnostic surgical pathology.

Epithelial membrane antigen--a diagnostic discriminant in surgical pathology: immunohistochemical profile in epithelial, mesenchymal, and hematopoietic neoplasms using paraffin sections and monoclonal antibodies

Glycoproteins isolated from human milk fat globule membranes, designated epithelial membrane antigen (EMA), have been detected immunohistochemically in most nonneoplastic epithelia and are potentially a highly effective marker for establishing the epithelial nature of neoplastic cells. With commercially available monoclonal antibodies and an indirect immunoperoxidase technique, EMA localization was evaluated in paraffin-embedded tissues from a wide variety of neoplasms (320 specimens). Adenocarcinomas from various primary sites (breast, lung, colon, stomach, pancreas, gallbladder, prostate, endocrine glands, ovary, kidney, thyroid) were immunoreactive for EMA in 88 of 97 cases (91 per cent). Cytoplasmic and apical luminal membrane staining were the most common patterns of immunoreactivity, with peripheral membrane staining or other patterns also seen in some neoplasms. Squamous cell (13 of 13 cases) and transitional cell (12 of 12 cases) carcinomas, small cell anaplastic carcinomas (12 of 12 cases), and mesotheliomas (six of six cases) were also uniformly EMA-positive. Malignant lymphomas of the Hodgkin's (15 cases) and non-Hodgkin's types (74 cases), except for the true histiocytic lymphomas and occasional T-cell lymphomas, were nonreactive for EMA. Neoplastic and nonneoplastic plasma cells showed variable EMA positivity. Endocrine neoplasms (17 cases), including carcinoid tumors, medullary carcinoma of thyroid, adrenocortical carcinomas and pheochromocytomas, and germ cell tumors (eight cases, embryonal carcinoma and seminoma), and a wide variety of soft tissue tumors (27 cases) generally lacked immunoreactivity for EMA; the exceptions to this finding were synovial sarcomas and an epithelioid sarcoma. Malignant melanomas (eight cases) were typically nonreactive. Based on the observations in this large series of neoplasms, EMA is an excellent marker of epithelial differentiation, appears to be highly reliable for discriminating between poorly differentiated carcinomas and malignant lymphomas, and is especially helpful in characterizing small cell anaplastic carcinomas. Epithelial membrane antigen immunoreactivity is well preserved in paraffin sections of routinely processed tissues, facilitating application of this technique in diagnostic surgical pathology.

Leu-M1--a marker for Reed-Sternberg cells in Hodgkin's disease. An immunoperoxidase study of paraffin-embedded tissues

Monoclonal antibody to Leu-M1, a granulocyte-related differentiation antigen, represents a highly effective reagent for detection of diagnostic Reed-Sternberg (R-S) cells and variants in paraffin-embedded tissues of Hodgkin's disease. In 69 of 73 cases of Hodgkin's disease (41 nodular sclerosis, 25 mixed cellularity, 4 lymphocyte predominance, and 3 lymphocyte depletion types), R-S cells were strongly immunoreactive for Leu-M1. Four cases of lymphocyte predominance Hodgkin's disease (nodular) were uniformly nonreactive for Leu-M1. In most of the positive cases (57/69, 83%), the majority (60-90%) of R-S cells and variants exhibited immunoreactivity for Leu-M1. A characteristic staining pattern included granular and/or vesicular cytoplasmic immunoreactivity, often with a prominent globular paranuclear reaction product, and membrane staining with highly irregular cytoplasmic borders. Evaluation of B-cell (37 specimens), T-cell (20 specimens), and true histiocytic (3 specimens) neoplasms and a case of mastocytosis revealed immunoreactivity for Leu-M1 only in 1 B-cell and 4 T-cell malignancies. The staining patterns in these cases, however, clearly differed from that observed for R-S cells. Studies of nonneoplastic lymphoid tissues (38 total) demonstrated that lymphoid cells were typically nonreactive; histiocytes revealed variable reactivity for Leu-M1. Occasional histiocytes of the sinusoidal network of lymph nodes, particularly in toxoplasmic lymphadenitis, exhibited a staining pattern (membranous/cytoplasmic/paranuclear) similar to that observed for R-S cells. Leu-M1 represents a potentially helpful diagnostic discriminant in the assessment of Hodgkin's disease and its distinction from non-Hodgkin's lymphomas and other lymphoid proliferations.

Optimal immunoreactivity of keratin proteins in formalin-fixed, paraffin-embedded tissue requires preliminary trypsinization. An immunoperoxidase study of various tumours using polyclonal and monoclonal antibodies

The effect of preliminary trypsinization on the immunoreactivity of keratin proteins in formalin-fixed, paraffin-embedded tissues of a variety of tumors (squamous cell carcinomas, adenocarcinomas, mesotheliomas, and transitional cell carcinomas) was evaluated. Three types of trypsin (Type II and Type IX porcine trypsin and Type III bovine trypsin) and varying concentrations of trypsin were assessed. Immunoreactivity of keratin proteins was determined using rabbit anti-keratin antibodies and monoclonal antibodies (combination of AE1 and AE3) and immunoperoxidase techniques. Preliminary trypsinization was mandatory for optimal immunoreactivity of keratin proteins using either polyclonal or monoclonal antibodies. Excellent results were obtained using Type II porcine trypsin at concentrations of 25 mg/dl for 30-45 min or 50 mg/dl for 20 min, at 37 degrees C. Trypsin treatment with excessive concentrations of enzyme and/or extended incubation times promoted tissue digestion and in some cases, yielded decreased immunoreactivity and altered staining patterns.

Leukocyte common antigen--a diagnostic discriminant between hematopoietic and nonhematopoietic neoplasms in paraffin sections using monoclonal antibodies: correlation with immunologic studies and ultrastructural localization

Immunohistochemical localization of human leukocyte common antigen (LCA), a major membrane glycoprotein restricted to leukocytes, was evaluated in paraffin sections of a wide variety of hematopoietic and nonhematopoietic tissues (294 specimens) with monoclonal antibodies (PD7/26 and 2B11). In nonneoplastic tissues, LCA was identified on B and T lymphocytes, with variable immunoreactivities for plasma cells and histiocytes. By light microscopy and ultrastructurally, LCA was localized predominantly to the cell membrane and was also present focally in the cytoplasm. Myeloid cells at all stages of maturation were non-reactive, as were erythroid cells, megakaryocytes, and all non-hematopoietic tissues. Monocytes and mast cells, however, revealed membrane staining for LCA. In nearly all non-Hodgkin's lymphomas of the B- and T-cell types (74 of 80; 93 per cent), the lymphoid infiltrate was immunoreactive for LCA. In specimens from patients with Hodgkin's disease (nodular sclerosis and mixed cellularity type), rare Reed-Sternberg cells stained for LCA. Neoplastic cells were consistently immunoreactive for LCA in specimens from patients with chronic lymphocytic leukemia of the B- or T-cell type, prolymphocyte leukemia, and hairy cell leukemia. However, tissues from only three of eight cases of acute lymphoblastic leukemia were LCA-positive, with most non-reactive specimens exhibiting CALLA (J5) positivity. In cases of multiple myeloma, only minor populations of plasmacytic cells exhibited membrane staining for LCA. Nonhematopoietic neoplasms (102 evaluated), including small cell anaplastic carcinomas, amelanotic melanomas, alveolar rhabdomyosarcomas, Ewing's sarcoma, and germ cell tumors, were uniformly non-reactive. Human LCA represents an excellent cell marker for paraffin sections, to distinguish hematopoietic neoplasms, particularly of the lymphoid type, from poorly differentiated tumors of epithelial, mesenchymal, or neural derivation.

Surgery for thyroid carcinoma

The cases of thyroid carcinoma treated at this hospital during the period 1948 to 1981 were reviewed retrospectively. Nine hundred eighty-six patients with thyroid nodules were operated on. One hundred fifty-two were thyroid carcinoma (59 papillary, 36 mixed papillary-follicular, 30 follicular, 20 anaplastic, 5 medullary, and 2 Hurthle cell tumors). There was a 92% follow-up for a mean of 10 years. In the last decade, patients presented at a younger age, the female predominance was diminished, and 15% had had previous neck irradiation. Surgery consisted of total (27) or subtotal thyroidectomy (89), lobectomy or nodulectomy (24), and biopsy (12). Total thyroidectomy had an incidence of postoperative complications that was 20 times higher than that with partial thyroidectomy (P less than 0.001). Disease-related death, recurrence, and survivor status were discussed. There was no significant difference between total versus subtotal thyroidectomy. This study reaffirms the usefulness of subtotal resection and the avoidance of morbidity of more radical total thyroidectomy surgery.

Immunohistochemical localization of smooth muscle myosin in normal human tissues

Immunohistochemical localization of smooth muscle myosin, an immunologically distinct contractile protein, was achieved using rabbit anti-human uterine smooth muscle myosin antibodies. In immunodiffusion studies and in cryostat sections, these antibodies were highly specific and reacted with smooth muscle myosin but not with platelet, skeletal muscle, or cardiac muscle myosin. To evaluate comprehensively the structural profile of smooth muscle elements in normal human tissues, an indirect immunoperoxidase technique (peroxidase-antiperoxidase) was applied to a wide variety of specimens. Parallel studies comparing cryostat sections with fixed (10% formalin, B5, Bouin's, or Zenker's solution) paraffin-embedded tissues revealed optimal immunoreactivity, sensitivity, and specificity of staining for smooth muscle myosin using frozen tissues. Strong immunoreactivity was present in muscular tissues such as blood vessels and the muscularis of gastrointestinal and genitourinary tracts. Distinct delineation of smooth muscle elements, including individual smooth muscle cells, and their specific patterns of alignment and organization, were observed, e.g., cells comprising the muscularis mucosae and extending into the lamina propria of the gastrointestinal tract, and myoepithelial cells of skin, exocrine glands, and breast. This method provides excellent morphologic preservation and readily permits unambiguous identification of individual cells containing smooth muscle myosin.

Immunologic heterogeneity of diffuse large cell lymphoma

The cellular lineage of 57 diffuse large-cell lymphomas (DLCLs) was determined using a panel of monoclonal antibodies directed against lineage-restricted and -associated T, B, and monocyte antigens. The majority (82%) were of B cell lineage as determined by the expression of sig and/or B1, with the remaining 16% being of T cell lineage and 2%, of monocyte-myeloid lineage. By the expression of other B cell-restricted and -associated antigens, two major and two minor subgroups could be identified. These subgroups expressed the following phenotypes: (1) B1+B4+sIG+B2- (51%); (2) B1+B4+sIg+B2+ (29%); (3) B1+B4+sIg-B2+ (10%); and (4) B1+B4-sIg+B2- (10)%. The morphology of transformed lymphocytes, the weak to absent expression of the early B cell antigens B2 and sIgD, and the absence of the late B cell differentiation antigens PCA-1 and PC-1 suggested that these tumors were the neoplastic counterparts of normal B cells at the mid-stages of differentiation. Further support for the notion that B-DLCLs correspond to transformed B lymphocytes was concluded from the observation that B cells could be identified in normal spleen that expressed the cell surface phenotype and morphological appearance of the majority of B-DLCLs.

Immuno-ultrastructural localization of involucrin in squamous epithelium and cultured keratinocytes

Involucrin immunoreactivity was localized ultrastructurally with protein A--gold in epidermis and cultured keratinocytes embedded in Lowicryl K4M. In the skin, immunoreactivity was found predominantly in cells of the granular layer and inner stratum corneum. The label was associated primarily with amorphous cytoplasmic material and especially keratohyaline granules. Some labeling was observed at the cell periphery, but little with keratin filaments. Tissue samples examined without aldehyde fixation showed relatively greater labeling in the outer stratum corneum than fixed tissue. In cultured cells, the labeling was also associated primarily with cytoplasmic granular material and to a lesser extent with the cell periphery. Upon treatment with the ionophore X537A, keratin filaments were found in aggregated arrays and the plasma membranes became convoluted. That involucrin immunoreactivity persisted in the cytoplasm in cultured cells and in vivo after cross-linking occurs could account for considerable isopeptide bonding detected in epidermal keratin fractions and indicates that not all the involucrin participates in envelope formation.

Hodgkin's disease, lymphocyte predominance type, nodular--a distinct entity? Unique staining profile for L&H variants of Reed-Sternberg cells defined by monoclonal antibodies to leukocyte common antigen, granulocyte-specific antigen, and B-cell-specific antigen

Using monoclonal antibodies to leukocyte common antigen, granulocyte-related antigen, and B-cell specific antigens, L&H variants of Reed-Sternberg (R-S) cells in Hodgkin's disease, lymphocyte predominance type (nodular), exhibited a unique staining profile as compared with R-S cells of other histologic types. L&H variants were strongly immunoreactive for leukocyte common antigen, as defined by monoclonal antibodies PD6/27 and 2B11; whereas other types of R-S cells were negative or rarely positive. R-S cells and variants in 69 cases of Hodgkin's disease of nodular sclerosis (41), mixed cellularity (25) or lymphocyte depletion (3) types, were consistently strongly immunoreactive for Leu-M1, a granulocyte-related antigen, while L&H variants were uniformly nonreactive (4 cases). B-cell specific antigens, detected by three pan-B-cell monoclonal antibodies, were observed only for L&H variants. These observations suggest that L&H variants of R-S cells represent a distinct type of transformed cell, possibly of B-cell origin, and do not share a common lineage with other types of R-S cells. These studies provide further evidence that Hodgkin's disease, lymphocyte predominance type, nodular, may represent a distinct entity.

Circulating monoclonal B lymphocytes in non-Hodgkin's lymphoma

Using a sensitive flow cytometric method ("kappa-lambda analysis"), we have found monoclonal B lymphocytes in the blood of 71 of 91 patients with non-Hodgkin's lymphoma. The presence of the B lymphocytes was independent of the histologic subclassification of the patient's disease. When we performed simultaneous analysis of the surface light-chain type in tumor tissue obtained by biopsy, the apparent light-chain type of the blood monoclonal cells corresponded with that of the tumor in 21 of 23 patients (P = 0.03). There was no correlation of the presence of these cells in the blood with morphologic evidence of bone-marrow involvement by lymphoma, but there was a strong correlation with clinical staging. Studies performed during prolonged clinical remission showed that whereas 16 of 25 patients with nodular non-Hodgkin's lymphoma had persistence of monoclonal lymphocytes, none of the 14 patients with diffuse histiocytic lymphoma in remission had these findings (P less than 0.005). Our analysis for B-cell clonal excess demonstrates the persistence of circulating monoclonal lymphocytes during complete remission in patients with forms of lymphoma that have a high probability of relapse, but we did not find these cells in patients in remission from categories of lymphoma in which prolonged remission is associated with cure. It is possible that the circulating monoclonal lymphocytes in patients with lymphoma are malignant cells, and their disappearance or persistence after remission may have prognostic importance.

Combination chemotherapy for advanced non-Hodgkin's lymphomas other than diffuse histiocytic or undifferentiated histologies

A combination chemotherapy program using methotrexate, bleomycin, doxorubicin, cyclophosphamide, vincristine, and dexamethasone (M-BACOD), which resulted in a high complete response rate and prolonged disease-free survival in lymphomas of the unfavorable diffuse histiocytic and diffuse undifferentiated histopathologic subgroups, was administered to 44 patients with advanced favorable and intermediate-prognosis non-Hodgkin's lymphomas, including nodular lymphoma of the poorly differentiated lymphocytic, mixed, and histiocytic subtypes, and diffuse lymphoma of the poorly differentiated lymphocytic or mixed histologic subtypes. High-dose methotrexate (3 g/m2) was given on Day 14 between cycles of bleomycin, doxorubicin, cyclophosphamide, vincristine, and dexamethasone, administered every 3 weeks for ten cycles. Leucovorin factor (10 mg/m2) was given iv 24 hours after the methotrexate infusion was completed, and was continued at 10 mg/m2 by mouth every 6 hours for 72 hours. Therapy was well-tolerated, with predictable myelosuppression in the majority of patients. The complete response rate was 57% (25 of 44 patients), including ten of 18 (56%) patients with nodular and 15 of 26 (58%) patients with diffuse lymphomas. Median overall follow-up among living patients is 65 months, 58 months for patients with nodular and 69 months for patients with diffuse histologic subgroups. Overall survival at 5 years was 64% for patients who achieved complete response, 32% for partial responders, and 0% for those patients who did not respond. Disease-free survival of complete responders was 43% at 5 years, with only one disease-related death noted after 36 months. The nodular and diffuse patient subgroups had similar overall and disease-free survivals. Although initial bone marrow involvement was documented in nine of 18 (50%) nodular patients and in 13 of 26 (50%) diffuse patients, CNS relapse occurred in only one complete and two partial responders. The prolonged disease-free survival observed after M-BACOD therapy demonstrates that durable responses can be achieved with intensive chemotherapy.

Keratin proteins and carcinoembryonic antigen in synovial sarcomas: an immunohistochemical study of 24 cases

Twenty-four synovial sarcomas were examined for the presence of keratin proteins by an indirect immunoperoxidase method with paraffin-embedded tissues. Keratin proteins were identified in 16 of 24 cases (67 per cent). Both the pseudoglandular and spindle cell areas of all eight of the biphasic synovial sarcomas and the spindle cells of eight of the 16 monophasic synovial sarcomas contained keratin proteins. In spindle cell areas, staining was observed in single cells and small cords and clusters of cells in the absence of cleft formation or other evidence of a pseudoglandular component. The predominant cytologic staining pattern in all cases was peripheral, with localization of staining to the cell membrane or adjacent areas, but diffuse and focal cytoplasmic staining patterns were also observed. No staining for keratin proteins was seen in 101 control cases, including 52 sarcomas of various types. Carcinoembryonic antigen was also identified in four of the 24 synovial sarcomas by an indirect immunoperoxidase technique. The identification of keratin proteins may be helpful in the pathologic diagnosis of synovial sarcoma, particularly the spindle cell monophasic variant.

Expression of human B cell-associated antigens on leukemias and lymphomas: a model of human B cell differentiation

A series of monoclonal antibodies that define B cell restricted and associated antigens was utilized in an attempt to characterize tumors of B lineage and to relate these tumors to B cell differentiative stages. Antigens that were previously shown to be B cell restricted on normal B lymphocytes were similarly expressed only on B cell malignancies. In contrast, antigens that were B cell associated were also found on tumors of other lineages. Moreover, on the basis of cell surface phenotypes, tumors of B cell origin were divided into three major subgroups, which corresponded to the level of differentiation of the malignant tumor cell: pre-B cell stage (non-T acute lymphoblastic leukemia and chronic myelocytic leukemia in lymphoid blast crisis); the mid-B cell stage (chronic lymphocytic leukemia, poorly differentiated lymphomas); and secretory B cell stage (large cell lymphomas and plasma cell tumors). A hypothetical model is derived that relates the malignant B cell to its normal cellular counterpart on the basis of cell surface expression of this panel of B cell-restricted and B cell-associated antigens.

Involucrin expression in normal and neoplastic human skin: a marker for keratinocyte differentiation

Involucrin is a recently recognized structural component of mature squamous epithelial cells. We examined involucrin expression using an immunoperoxidase technique in normal skin and in a variety of epidermal hyperplasias and neoplasms to determine whether distinctive staining patterns existed within these lesions. Four patterns of reactivity were observed: diffuse intracellular staining typical of keratinocytes of the upper third of normal epidermis and epidermal hyperplasias and benign neoplasms; staining at cell borders, seen principally in benign epidermal neoplasms; patchy staining characteristic of squamous cell carcinoma in situ; and absence of staining in benign and neoplastic basaloid epithelium. Invasive nests of squamous cell carcinomas were negative for involucrin reactivity, whereas pseudoinvasive tongues of epithelium at the bases of keratoacanthomas were focally positive. These results suggest that immunoperoxidase staining for involucrin may be useful in distinguishing certain benign from malignant epidermal neoplasms as well as in understanding the altered maturation and kinetics of proliferative processes afflicting keratinocytes.

Cytofluorometric detection of B cell clonal excess: a new approach to the diagnosis of B cell lymphoma

A sensitive cytofluorometric technique, the "kappa-lambda test," permits detection of small numbers of monoclonal B lymphocytes (clonal excess). Such a method might represent a new diagnostic tool for diagnosis of non-Hodgkin's lymphomas, potentially providing definitive evidence of lymphomatous involvement in cases equivocal by standard immunologic methods. To determine the significance of detecting B cell clonal excess in lymphoid tissues, we applied the kappa-lambda test to cell suspensions from 60 consecutive specimens suspected to involvement by malignant lymphoma. Results were correlated with the pathologic diagnosis and with standard cell marker studies in each case. B cell clonal excess was observed in 24 of the 25 cases of non-Hodgkin's lymphoma of B cell origin, including a single case involving early detection of recurrence. None of the remaining cases, including benign reactive hyperplasia, T cell lymphoma, and Hodgkin's disease, showed evidence of B cell clonal excess. Selective examination of cell subpopulations was also achieved using this cytofluorometric method. We conclude that the detection of B cell clonal excess by the kappa-lambda test represents a new approach to the diagnosis of B cell lymphoma, which provides certain advantages over more standard methods of cell marker analysis.

Extramammary Paget's disease--evidence for an apocrine origin. An immunoperoxidase study of gross cystic disease fluid protein-15, carcinoembryonic antigen, and keratin proteins

The histogenesis of extramammary Paget's disease has long remained unresolved and controversial. In an attempt to delineate the origin of the neoplastic cells in this disease, the immunoperoxidase localization of gross cystic disease fluid protein (GCDFP-15), a marker of apocrine epithelium, carcinoembryonic antigen (CEA), and keratin proteins, was determined for seven cases of extramammary Paget's disease (five vulvar, one anogenital, and one axillary). Immunoreactivity for GCDFP-15 was localized within Paget cells in six of our seven cases, including five cases from the vulva and one case from the axilla. CEA was present in the Paget cells in all seven cases. None of the Paget cells exhibited immunoreactivity for keratin proteins. Within normal skin, eccrine glands were immunoreactive for both keratin and CEA, whereas GCDFP-15 localized only to apocrine ducts and glands. Our findings strongly support an apocrine cell derivation for extramammary Paget's disease.

Evaluation of squamous epithelium in adenoacanthoma and adenosquamous carcinoma of the endometrium: immunoperoxidase analysis of involucrin and keratin localization

A study was undertaken to determine whether immunoperoxidase stains for keratin and involucrin, the latter a protein present in cells of stratified squamous epithelium that have differentiated beyond the basal stage, distinguish any differences in squamous cells present in the adenoacanthoma from those in the adenosquamous carcinoma of the uterine corpus. Forty-eight tumors were studied, of which 33 were adenoacanthomas and 15 adenosquamous carcinomas. The patients with adenoacanthomas were slightly younger (mean 61.5 vs. 64.5 years) and had tumors that were generally better differentiated than the adenosquamous carcinomas. The squamous epithelium in every tumor, regardless of histologic type, stained positively for keratin. There were no obvious differences in staining when tumors were stratified for histologic type, grade, or location within the tumor. The glandular portion of both tumor types stained irregularly, but nonetheless positively, for keratin in 71% of the cases. Involucrin was detected in 57% of adenoacanthomas and 87% of adenosquamous carcinomas. The deeper or more central portion of the squamous morules stained only if the more superficial or peripheral areas were positive. The extent of the involucrin staining was less in the adenosquamous carcinomas than in the adenoacanthomas. The glandular component of the tumors did not stain for involucrin. It is concluded that no qualitative differences in the staining reactions with respect to keratin and involucrin distinguish the adenoacanthomas from the adenoaquamous carcinoma. These findings support the argument that the adenoacanthoma and adenosquamous carcinoma represent a spectrum of squamous differentiation in a single tumor type.

Papillomavirus infection of the cervix. III: Relationship of the presence of viral structural proteins to the expression of involucrin

Forty-two cervical biopsies with cervical intraepithelial neoplasia were compared with respect to the expression of human papillomavirus (HPV) structural proteins and the expression of the cellular structural protein involucrin, a marker of suprabasal squamous differentiation. HPV structural protein and involucrin expression displayed an inverse correlation with the severity of dysplasia. Both of these proteins were detected in 11 of 28 cases (39%) of mild and moderate dysplasia, but in only two of 14 (14%) cases of severe dysplasia. This difference was statistically significant (p less than 0.001). The presence of HPV was also associated with expression of involucrin in the full thickness of the epithelium, including the basal layer, and an altered staining pattern in the more superficial cells, particularly the koilocytotic cells. These findings support the hypothesis that squamous differentiation is required for the expression of viral structural proteins and that HPV infection begins in the basal epithelium. The study also demonstrates the utility of involucrin staining in differentiating virus-induced cytologic atypia from true neoplasia.

Ampullary somatostatinoma: psammomatous variant of gastrointestinal carcinoid tumor--an immunohistochemical and ultrastructural study. Report of a case and review of the literature

A 28-year-old man presented with epigastric pain and obstructive jaundice associated with a histologically and immunologically unusual variant of carcinoid tumor involving the ampulla of Vater. The tumor contained abundant psammoma bodies and exhibited immunoreactivity only for somatostatin. Immunoperoxidase studies for insulin, glucagon, vasoactive intestinal peptide, calcitonin, serotonin, and ACTH had negative results. In contrast to most somatostatinomas of pancreatic origin, clinically this ampullary somatostatinoma was not accompanied by features of the somatostatinoma syndrome. A literature review of the clinical and hormonal features in reported cases of gastrointestinal and pancreatic somatostatinomas is presented.

Immunohistochemical localization of glandular kallikrein in the endocrine and exocrine human pancreas

Fab fragments from two new monospecific anti-human tissue kallikrein sera were examined for their capacity to inhibit the functional activities of purified human urinary kallikrein and purified human pancreatic kallikrein. Fragments from a new anti-urinary kallikrein serum and from an anti-pancreatic kallikrein serum yielded mixed inhibition of kinin-generating activity and minimal inhibition of esterolytic activity. In contrast to the previously described "active site directed" anti-urinary kallikrein, these new antisera demonstrated little specificity for epitopes near the enzymatic site of urinary or pancreatic kallikrein. When used to localize kallikrein antigen in human pancreas obtained at surgery, IgG fractions of the new anti-kallikrein sera yielded moderate acinar and ductal staining in the absence of pretreatment of the tissue with trypsin or pronase. Short incubation with 0.125 mg/ml of either enzyme permitted the discrete localization of islet beta cell kallikrein antigen, while increased pronase concentrations decreased kallikrein antigen in both islets and exocrine tissue and led to islet destruction. Both antibody specificity and tissue preparation influence kallikrein localization in human pancreas.

Sequestered substernal goiter

A young woman with a normally located and only subtly nodular thyroid gland in the neck was found to have a clinically distinct and radioisotopically "cold" anterior mediastinal mass, which proved to be a benign colloid adenoma. While this constellation of findings usually suggests the presence of a nonthyroidal neoplasm, eg, lymphoma, thymoma, or teratoma, our case illustrates that sequestered benign nodular goiter should also be considered in the differential diagnosis. Clinical clues, such as a nodular thyroid gland, movement of the mass with deglutition, and a family history of nodular goiter, should suggest this possibility. A characteristic computed tomographic appearance may also prove useful in recognition of this rare disorder.

Localization of keratin proteins in the human epidermis by a postembedding immunoperoxidase technique

Individual keratin species were localized ultrastructurally to the tonofilaments and tonofibrils of the human epider-misusing a postembedding immunoperoxidase method. Low molecular weight keratin (45 kD) was localized primarily to the stratum basale and displayed a fine cytoplasmic staining of individual tonofilaments and some tonofibrillar staining. Higher molecular weight keratins (55 and 63 kD) were found predominantly in the suprabasal, differentiated squamous epithelial cells, staining tonofibrils with a web-like pattern. The technique utilized is suitable for studying the distribution of keratin proteins in normal and disease states.

Improved prognosis of diffuse histiocytic and undifferentiated lymphoma by use of high dose methotrexate alternating with standard agents (M-BACOD)

A new combination chemotherapy program (M-BACOD) was administered to 101 patients with advanced diffuse histiocytic and diffuse undifferentiated lymphoma (DHL and DUL). High dose methotrexate (M) 3 g/m2 with leucovorin factor rescue was given on day 14 between cycles of bleomycin (B), adriamycin (A), cyclophosphamide (C), oncovin (O), and dexamethasone (D) administered every 3 weeks for 10 cycles. The complete remission rate (CR) was 72% in all 101 patients or 77% in 95 evaluable patients. The median follow-up is 3 yr 2 mo with one-third of CR patients followed beyond 4 yr. Twenty-six percent of CR patients have relapsed with a projected 5-yr survival rate of 80% (5-yr disease-free rate 65%). The overall survival of all 101 study patients reaches a plateau at 59% projected out to 5 yr. Patients with prior therapy had a significantly lower CR rate than those without prior treatment (p = 0.001); however, no other unfavorable prognostic characteristics could be identified. Relapse in the central nervous system CNS occurred in only 5.4% of CR patients. M-BACOD results in prolonged survival and possible cure in a high proportion of all patients with DHL and DUL.