Extranodal hematopoietic/lymphoid disorders. An introduction.

Extranodal lymphomas are increasing in frequency owing in part to a true increase, but also as a consequence of AIDS and the recognition by pathologists that many cases formerly regarded as extranodal lymphoid hyperplasias or as pseudolymphomas are low-grade lymphomas of mucosa-associated lymphoid tissue (MALT) type. However, most primary extranodal lymphomas are aggressive lymphomas, usually of large B-cell type. Extranodal T-cell lymphomas also occur, such as the NK/T-cell lymphomas of the sinonasal area, the subcutaneous panniculitic T-cell lymphomas, and anaplastic large cell lymphomas. The aggressive lymphomas need to be distinguished from extranodal myeloid leukemias, whereas the low-grade lymphomas of MALT need to be distinguished from other extranodal lymphomas composed of small lymphocytes, such as mantle cell and follicular lymphomas. MALT lymphomas also must be differentiated from the various forms of extranodal lymphoid hyperplasia. Caution is required when determining this differentiation, since the discovery of a clonal cell population in a clinically and pathologically innocuous extranodal lymphocytic infiltrate does not necessarily equate with a diagnosis of malignant lymphoma. In this setting, a more appropriate designation might be a neoplasm or disorder of "uncertain malignant potential."

Are there site-specific differences among the MALT lymphomas--morphologic, clinical?

To qualify as a low-grade lymphoma of mucosa-associated lymphoid tissue (MALT) type, lymphomas at different extranodal sites must conform to specific morphologic features. Lymphoepithelial lesions are typical, and follicular colonization is common. Regardless of site, many MALT lymphomas are associated with a predisposing condition, infectious or autoimmune, leading to the acquisition of extranodal MALT. MALT lymphomas in different regions usually have limited disease and indolent clinical courses in which survival does not substantially differ from healthy controls. There is a tendency for diverse cytologic expressions among different MALT lymphomas, such as small lymphocytes in the lung, monocytoid cells in salivary glands, and plamacytic cells in the thyroid and skin, but the site-specific morphologic differences mainly reflect the unique topographic characteristics of the involved organ, and these topographic features also influence the clinical traits. Some of the unparalleled features of MALT lymphomas in different sites include the association of gastric MALT lymphomas with Helicobacter pylori, the lymphangitic distribution of pulmonary MALT cases, and the relationship between MALT lymphomas of the salivary gland and thyroid with Sjögren's syndrome and Hashimoto's thyroiditis, respectively. The ocular cases and those of the skin, breast, and dura also have characteristic clinical modes of presentation largely owing to the anatomic locale of the lymphoma.

Ipsilateral femoral neck and shaft fractures.

Ipsilateral, concomitant femoral neck and shaft fracture is a rare fracture pattern encountered by orthopaedic surgeons. We review 11 cases of this fracture pattern. Treatment was by reduction and stabilization of the femoral neck fracture with one or more cannulated screws, followed by fixation of the femoral shaft using a Russell-Taylor reconstruction nail or a Russell-Taylor Delta reconstruction nail. When properly sequenced, this has proven to be a successful treatment method in these dual fractures, resulting in a low complication rate. No avascular necrosis of the femoral head or nonunion of either fracture site occurred. In our series, one patient with delayed union had varus angulation of 120 degrees of the femoral neck. Good functional outcome based on patients' ability to perform activities of daily living was achieved.

Cloning and regulation of rat tissue inhibitor of metalloproteinases-2 in osteoblastic cells.

Rat tissue inhibitor of metalloproteinases-2 (TIMP-2) was cloned from a UMR 106-01 rat osteoblastic osteosarcoma cDNA library. The 969-bp full-length clone demonstrates 98 and 86% sequence identity to human TIMP-2 at the amino acid and nucleic acid levels, respectively. Parathyroid hormone (PTH), at 10(-8) M, stimulates an approximately twofold increase in both the 4.2- and 1.0-kb transcripts over basal levels in UMR cells after 24 h of exposure. The PTH stimulation of TIMP-2 transcripts was not affected by the inhibitor of protein synthesis, cycloheximide (10(-5) M), suggesting a primary effect of the hormone. This is in contradistinction to regulation of interstitial collagenase (matrix metalloproteinase-1) by PTH in these same cells. Nuclear run-on assays demonstrate that PTH causes an increase in TIMP-2 transcription that parallels the increase in message levels. Parathyroid hormone, in its stimulation of TIMP-2 mRNA, appears to act through a signal transduction pathway involving protein kinase A (PKA) since the increase in TIMP-2 mRNA is reproduced by treatment with the cAMP analogue, 8-bromo-cAMP (5 x 10(-3) M). The protein kinase C and calcium pathways do not appear to be involved due to the lack of effect of phorbol 12-myristate 13-acetate (2.6 x 10(-6) M) and the calcium ionophore, ionomycin (10(-7) M), on TIMP-2 transcript abundance. In this respect, regulation of TIMP-2 and collagenase in osteoblastic cells by PTH are similar. However, we conclude that since stimulation of TIMP-2 transcription is a primary event, the PKA pathway must be responsible for a direct increase in transcription of this gene.

Reed-Sternberg-like cells in low-grade lymphomas are transformed neoplastic cells of B-cell lineage.

Multinucleated giant cells resembling Reed-Sternberg (RS) cells are occasionally observed in high-grade lymphomas of the large-cell or immunoblastic type, but much less commonly in low-grade lymphomas. This study was conducted to determine whether RS-like cells found in seven B-cell low-grade lymphomas were immunologically similar to the neoplastic cells in the lymphoma or to the true RS cells seen in Hodgkin's disease, and whether they were therefore indicative of a composite lymphoma. Immunohistochemical studies were performed on paraffin sections of the seven low-grade (one small lymphocytic, one mantle zone, and five follicular) lymphomas with a panel of antibodies reactive with leukocyte common antigen (LCA), B-cell, T-cell, and Hodgkin's disease associated antigens. The RS-like cells were reactive with LCA (four of six), L26 (seven of seven), LN1 (five of six), LN2 (two of six), and MB2 (three of six). No positive staining was seen with either Leu-M1 or Ber-H2. The RS-like cells in the mantle zone lymphoma expressed L26, Leu-22, and kappa cytoplasmic light chains. This immunophenotype is similar to that of the neoplastic small lymphocytic cells. One of the low-grade follicular lymphomas progressed to an immunoblastic lymphoma with many RS-like cells. Paraffin immunohistochemistry on both lesions revealed a similar B-cell phenotype for the RS-like cells. Immunogenetic studies revealed B-cell and bcl-2 gene rearrangements in the immunoblastic lymphoma. These results indicate that RS-like cells in low-grade lymphomas are transformed neoplastic cells of B-cell lineage. With careful morphologic examination augmented by immunohistochemical studies, these lesions can be differentiated from Hodgkin's disease and from composite lymphomas of the combined Hodgkin's and non-Hodgkin's type.

Splenic lymphoid hyperplasias versus lymphomas/leukemias. A diagnostic guide.

An accurate diagnosis of a lymphoid infiltrate in the spleen is based on several essential factors. 1. The spleen must be well fixed and the sections of high technical quality. 2. The pathologist has to be congnizant of the predominant distributional features, whether primarily in the white or in the red pulp, of the various lymphoid infiltrates that result in splenomegaly. 3. A differential diagnostic scheme also should be based on the predominant histologic pattern and cell type. 4. Immunophenotypic and occasionally molecular genetic studies are imperative for refinement and verification of the histologic diagnosis.

High-risk germ cell tumors in men. High response rate and severe toxicity with cisplatin, vinblastine, bleomycin, and etoposide.

BACKGROUND: In an attempt to improve the complete remission and cure rate of advanced, bulky, high-risk germ cell cancer in men, a "high-dose" cisplatin, vinblastine, bleomycin, and etoposide (PVeBV) regimen was introduced. METHODS: Ten men with biopsy-proven germ cell tumors who had one or more poor prognostic features were treated with PVeBV. RESULTS: Six of the 10 had complete remissions and are long-term survivors. The most devastating toxicity, which resulted in the death of three patients, was progressive respiratory failure. It was postulated that renal tubular injury prolonged the renal clearance of bleomycin, intensifying the patient's pulmonary exposure to this drug and increased the susceptibility to pulmonary injury at lower than expected cumulative doses of bleomycin. CONCLUSIONS: Modifications of the regimen to reduce toxicity without diminishing the efficacy should be considered before PVeBV is adopted for general use.

Splenic involvement by aggressive malignant lymphomas of B-cell and T-cell types. A morphologic and immunophenotypic study.

To determine whether there are any consistent morphologic differences between B-cell and T-cell aggressive non-Hodgkin's lymphomas of the spleen, the authors analyzed 16 spleens involved by mixed cell (1 case) or large cell (15 cases) lymphomas. Immunologic data were derived from cell suspensions or frozen tissue in each case. Five cases had a T-cell phenotype, and 11 were B-cell. Morphologic features favoring a T-cell phenotype included epithelioid histiocytic reactions, confinement of the lymphomas to the splenic T-zones (periarteriolar lymphoid sheath and marginal zone), and clear cell or polymorphous cytologic features. Features favoring a B-cell phenotype included multiple discrete nodules in the white pulp, large coalescent tumor nodules in association with small lymphocytic lymphoma, and large non-cleaved or immunoblastic plasmacytoid cytologic characteristics. Four cases were unusual because most neoplastic large cells were distributed diffusely or formed only small aggregates in the red pulp without definite tumor masses or nodules involving the white pulp. Because of this distribution and the frequently encountered erythrophagocytosis by benign-appearing histiocytes, these cases resembled malignant histiocytosis. A T-cell phenotype was predicted for all four cases; however, only one case, a lymphoma with polymorphous cytologic characteristics, was of T-cell lineage. The other three cases were of B-cell lineage. The authors' results indicate that in most instances the B-cell or T-cell nature of aggressive splenic lymphomas is predictable from the distributional and cytologic features. As in lymph nodes, there are cases for which the morphologic characteristics of B-cell and T-cell lymphomas are indistinguishable.

Monocytoid B-cell lymphoma in patients with Sjögren's syndrome: a clinicopathologic study of 13 patients.

A recent clinicopathologic study of a series of patients with monocytoid B-cell lymphoma (MBCL) indicated that there is a frequent association between MBCL and Sjögren's syndrome (SS) and raised the possibility of a relationship between these two disease entities. To further investigate the possible relationship of MBCL and SS, we studied pathologic and clinical characteristics of 13 patients with MBCL who had clinically documented SS. In all patients, the lymphoma had the characteristic morphologic features of MBCL, and immunologic and molecular hybridization studies confirmed the B-cell nature of the lymphoma. Twelve of the 13 patients were female, with a median age of 66 years at diagnosis. Eleven had localized disease and presented with either salivary gland or cervical lymph node enlargement; one patient presented with a breast mass, and another with generalized lymphadenopathy and hepatosplenomegaly. In five of 13 patients, the MBCL was associated with or progressed to large cell lymphoma. In two patients, there was bilateral involvement of the parotid gland; one had a synchronous high-grade lymphoma in both parotid glands. In two patients, bone marrow biopsies showed involvement by MBCL. Eleven patients are alive 2 to 55 months after the diagnosis of MBCL. One patient died with the disease 8 months after the initial diagnosis. Another patient died of an unrelated cause without evidence of disease 16 months after the diagnosis of MBCL. We conclude that there is a more than fortuitous association between MBCL and SS. This concept is consistent with previously reported observations of reactive monocytoid B cells in patients with benign lymphoepithelial lesions of salivary glands, which may result from selective homing of reactive monocytoid B lymphocytes to the benign lymphoepithelial lesions and their subsequent neoplastic transformation.

Survival Experience of 195 Patients with Hairy Cell Leukemia Treated in a Multi-Institutional Study with Interferon-Alfa 2B.

One hundred ninety-five patients were entered into a multi-institutional study of interferon alfa 2b from 1983-1986; follow-up was completed through June 1989. A complete remission was documented in 7 patients, a partial remission in 152 patients, a minor response in 10 patients, and no response in 26 patients. One-hundred fifty-nine of the 195 patients treated (81%) had a normalization of their peripheral blood counts by the criteria used. To date, 17 patients have died. Only 3 of the 159 patients (2%) with a PR or CR have expired. Three of 10 MR patients have expired and 11 of 26 NR patients have expired. Of the 11 who expired, 7 did so before receiving an adequate duration of treatment. Three of the NR patients died within 1 week of starting interferon from intracranial hemorrhages secondary to severe thrombocytopenia (present prior to initiation of interferon) and 4 NR patients died of infectious deaths within 2 months of initiating interferon therapy secondary to severe neutropenia (present prior to initiation of interferon). Of the 17 NR's who remained alive and on-study for at least 6 months, only 2 eventually died, both after failing subsequent pentostatin therapy. Systemic therapy with agents that induce a more rapid response such as pentostatin or 2-chlorodeoxy-adenosine, or the combination of interferon plus growth factor are indicated in these severely cytopenic patients.

Lymphoid hyperplasia and malignant lymphoma occurring in the ocular adnexa (orbit, conjunctiva, and eyelids): a prospective multiparametric analysis of 108 cases during 1977 to 1987.

We performed a prospective multiparametric correlative clinical, histopathologic, and immunologic analysis of 117 ocular adnexal lymphoid proliferations developing in 108 patients between October 1977 and July 1987. The ocular adnexal lymphoid proliferations were distributed among the 108 patients as follows: orbit 69 (64%), conjunctiva 30 (28%), and eyelids nine (8%). The 117 ocular adnexal lymphoid proliferations were classified as follows: polyclonal lymphoid hyperplasia, 32 (22 orbit, nine conjunctiva, one eyelid) (27%); monoclonal B cell lymphoma, 81 (48 orbit, 25 conjunctiva, eight eyelid) (69%); null cell lymphoma, one (orbit) (1%); and histologically indeterminate, three (one each: orbit, conjunctiva, eyelid) (3%). Patients presenting with ocular adnexal polyclonal lymphoid hyperplasia and monoclonal B cell lymphoma, and patients developing unilateral and bilateral ocular adnexal lymphoid proliferations did not differ significantly with respect to age, sex, presenting complaints, duration of symptoms, or ophthalmic findings. Classifying ocular adnexal lymphoid proliferations into benign and malignant categories by histopathologic criteria and into polyclonal and monoclonal B cell categories by immunophenotypic criteria was not useful in predicting eventual outcome, including the occurrence of extraocular lymphoma. However, the clinicopathologic characteristics did differ according to the anatomic site of involvement and histopathology of the ocular adnexal lymphoid proliferations. Lymphoid infiltrates of the conjunctiva were associated with a lower incidence of extra-ocular lymphoma (20%) than were those of the orbit and eyelid, 35% and 67%, respectively (statistically significant, P less than .03). Ocular adnexal small lymphocytic and intermediate lymphocytic lymphomas were less often associated with extra-ocular lymphoma than were ocular adnexal lymphomas of all other histologic types, 27% and 46%, respectively (P less than .09). However, the single most important and statistically significant prognostic factor in these patients was the extent of disease at the time of presentation with an ocular adnexal lymphoid proliferation (P less than .001). Eighty-six percent of patients presenting with a unilateral or bilateral clinical stage lE ocular adnexal lymphoid proliferation, regardless of the histopathology or the immunophenotype, had a benign indolent clinical course and failed to develop ocular or extra-ocular lymphoma during a median follow-up period of 51 months. The results of this study substantially improve our understanding of extranodal small lymphocytic proliferations in general, and those of the ocular adnexa in particular.

A clinicopathologic study of malignant lymphomas of the nose, paranasal sinuses, and hard palate, including cases of lethal midline granuloma.

Malignant lymphomas of the nose, paranasal sinuses, and hard palate show marked clinicopathologic, immunologic, and prognostic diversity. The clinical features and pathologic spectrum of these lesions were studied in 20 cases (11 female and 9 male cases) with a mean age of 51 years at initial presentation. Malignant lymphomas of the large cell type were most frequently encountered (11/20). The next largest category was malignant lymphoma, diffuse, mixed small and large cell type (six of 20). Two thirds, 13 of 20 cases, had morphologic features suggestive of peripheral T-cell lymphomas. Necrosis, an angiocentric growth pattern, and epitheliotropism were found in nine, eight, and three cases, respectively. Of ten cases immunophenotyped on fresh-frozen or fixed, paraffin-embedded tissue sections, eight had a T-cell phenotype and two had a B-cell phenotype. Of 17 patients with sufficient follow-up data, ten are alive (median follow-up 33 months) and seven are dead (median survival 12 months). Patients with clinical Stages IE and IIE did not have a superior 5-year survival to those with more advanced disease. Histologic type also did not correlate with survival but this may be due to the aggressive histologic grade of the majority of cases and the retrospective nature of this study. The authors conclude that, despite the overall high-grade histologic type, the pathologic spectrum of malignant lymphomas involving this anatomic region is broad. Furthermore, some cases do not fit well into the National Cancer Institute (NCI) Working Formulation but more closely resemble the histologic features of peripheral T-cell lymphomas described in Japan.

Small lymphocytic lymphoma: a clinicopathologic analysis of 268 cases.

We analyzed specimens from 268 patients with small lymphocytic lymphoma (SL) to identify prognostic factors significant for survival. These patients were staged and treated according to the protocols of the Cancer and Leukemia Group B, Eastern Cooperative Oncology Group, Southeastern Cancer Study Group, and the Southwest Oncology Group. Univariate analysis showed that a large-cell grade greater than I, WBC greater than 10,000/microL, hemoglobin (Hgb) less than 11 g/dL, age greater than or equal to 55 years, and failure to respond to treatment were all poor prognostic factors. Multivariate analysis showed that large-cell grade, age, degree of capsular invasion, and symptom type were independently associated with survival. Separate analyses of cases with and without leukocytosis indicated differences in survival. In patients without leukocytosis, age, presence or absence of anemia, and treatment response were significant prognostic variables; in patients with leukocytosis, large-cell grade, presence or absence of anemia, symptom type, and treatment response were significantly related to survival. Multivariate analysis showed that age was the only significant independent prognostic variable in patients without leukocytosis; in patients with leukocytosis, symptom type, large-cell grade, and bone marrow involvement were independently associated with survival. We conclude that several parameters, both clinical and pathologic, should be assessed at the initial diagnosis of SL to predict prognosis better.

Reactive lymphadenopathies.

Reactive lymphadenopathies often pose a diagnostic problem. The distinction of a reactive from a neoplastic lymph node requires the application of general histologic criteria that traditionally have involved the evaluation of cytologic features including cellular polymorphism v monomorphism and the presence or absence of cytologic atypia. Although these cytologic criteria remain valid, they are not inviolate and exceptions exist that may result in diagnostic ambiguity. In addition, the interpretation of a reactive process in a lymph node is predicated on the evaluation of the dominant histologic architectural pattern and on a systematic approach to the diagnosis. The patterns specifically include whether the nodal architecture is predominantly diffuse, mixed interfollicular and follicular, follicular, or sinusoidal. Under each of these dominant architectural configurations, a host of benign reactive diagnoses may be assigned. An awareness of the various diagnostic categories for each major histologic pattern, the range and subtleties of their histologic expression, and the application of new methods, such as immunology to determine clonality, have resulted in simultaneous narrowing of the diagnostic possibilities and expansion of our comprehension of the reactive lymphadenopathies.

Monocytoid B-cell lymphoma. Clinicopathologic study of 21 cases of a unique type of low-grade lymphoma.

The morphologic and immunologic features of three cases of an unusual and distinct B-cell lymphoma were recently described and termed monocytoid B-cell lymphoma (MBCL) because of the striking resemblance of the neoplastic cells to reactive monocytoid B-lymphocytes. The morphologic spectrum and the clinical behavior of MBCL were investigated in a series of 21 patients. This study indicates that patients with MBCL usually present with lymphadenopathy and Stage I or II disease. MBCL also occurs at extranodal sites including the salivary gland. Because four of the patients with MBCL had Sjögren's syndrome with characteristic laboratory profiles, these results raise the possibility that there may be a relationship between MBCL and Sjögren's syndrome. Eight patients were male and 13 female (M:F = 1:1.6), and MBCL primarily involved the elderly (median age, 66 years). The most striking clinical findings were high percentages of complete remissions and long survival times indicating that MBCL is a low-grade lymphoma. Of 21 patients investigated, 18 were in complete remission at the time of completion of this study. Two patients died with the disease and one was lost to follow-up. Patients with localized MBCL may have a better survival rate than those with generalized disease. Like other low-grade lymphomas, MBCL can progress to a higher grade lymphoma of large cell type. Unlike other low-grade lymphomas, in MBCL splenomegaly, bone marrow involvement, and leukemic conversion are uncommon.

T-cell-rich lymphoproliferative disorders. Morphologic and immunologic differential diagnoses.

To differentiate peripheral T-cell lymphomas (PTCL), the authors evaluated the results of T11 monoclonal antibody studies on consecutive cell suspensions prepared from 509 lymph nodes from various lymphoproliferative disorders (LPD). They used T11 (CD2) positivity to identify those LPD in which the content of T cells was high. There were 266 (52%) cell suspensions which contained more than 50% T11-positive cells. More than 75% of the following non-Hodgkin's lymphomas had over 50% T11-positive cells: diffuse mixed cell (DM), diffuse atypical poorly differentiated lymphocytic and lymphoblastic lymphomas; mycosis fungoides; and true histiocytic lymphoma. Eleven cell suspensions had more than 90% T11-positive cells; four were involved by B-cell lymphomas. The cell suspensions prepared from nine of 14 diffuse large cell lymphomas of the T-cell type had more than 50% T11-positive cells. Of these, three of five cases of the polymorphous subtype had fewer than 50% T11 cells, but six of seven lymph nodes of the clear-cell type had more than 50% T11-positive cells. Each of seven DM samples of the T-cell type contained over 50% T11 cells; none had a polymorphous appearance. In the 112 cases of reactive LPD studied, more than 75% of cases of necrotizing lymphadenitis, dermatopathic lymphadenitis, angioimmunoblastic lymphadenopathy, and those with lymph nodes with no specific reactive pattern had more than 50% T11-positive cells. The authors' findings indicate that T11 positivity is a reliable T-cell marker in reactive and neoplastic LPD except for those cases of PTCL with a polymorphous appearance; these tend to lose T11-expression. A multi-parameter diagnostic approach is required in the following LPD: (1) PTCL which are T11-negative; (2) PTCL of small lymphocytic type having an unremarkable T-cell phenotype; (3) SIg-negative B-cell lymphomas which are rich in nonneoplastic T cells; (4) non-Hodgkin's lymphomas with minimal disease which are rich in reactive T cells; and (5) polymorphous large cell proliferations.

Variability in interpretation of immunohistologic findings in lymphoproliferative disorders by hematopathologists. A comprehensive statistical analysis of interobserver performance.

Eight hematopathologists independently reviewed 56 consecutive cases of benign and malignant lymphoproliferative disorders (LPD) to determine: (1) the degree of interobserver agreement on the interpretation of immunologic findings on fresh-frozen sections alone and on that of the immunologic findings in conjunction with corresponding hematoxylin and eosin (H & E)-stained histologic sections; (2) whether prior knowledge of morphologic characteristics influences the interpretation of immunohistologic sections; (3) whether immunologic phenotype could be predicted reliably based solely on study of histologic sections; and (4) the significance of immunologic data as an aid in the interpretation of histologic sections. The study was carried out in three independent review sessions consisting of (1) review of immunohistologic sections only, (2) review of the same immunohistologic sections together with histologic sections, and (3) review of the histologic sections alone. A consensus diagnosis was defined as agreement of five or more pathologists on the final diagnosis and identification of the immunophenotype. When the authors compared the total number of major disagreements in the first review session with those in the second, the accuracy of the determination of immunophenotype in the second session was clearly superior (P less than 0.05). Similarly, the total number of major disagreements in the second review session was significantly lower than that in the third review session (P less than 0.001). When histologic diagnoses in the second session were compared with those in the third session, it became apparent that the immunologic data helped the pathologist to correct major misinterpretations in 14 cases (25%). This study is the first to demonstrate quantitatively that (1) knowledge of morphologic features influences and greatly enhances the accuracy of the interpretation of immunologic findings, (2) the immunophenotype of LPD cannot be predicted based on morphologic findings alone, and (3) immunologic findings improve the accuracy of interpretation of histologic findings in situations in which a diagnosis cannot be made from morphologic features only.

Lymphoid neoplasia associated with the acquired immunodeficiency syndrome (AIDS). The New York University Medical Center experience with 105 patients (1981-1986).

We identified 105 patients with lymphoid neoplasia associated with the acquired immunodeficiency syndrome (AIDS) at the New York University Medical Center from 1981 through 1986: 89 had non-Hodgkin lymphoma; 13, Hodgkin disease; and 3, chronic lymphocytic leukemia. Immunophenotypic and antigen receptor gene rearrangement analysis showed the B-cell origin of all non-Hodgkin lymphomas studied and the clonal suppressor-cytotoxic T-cell subset origin of the chronic lymphocytic leukemias. We classified 69% of the non-Hodgkin lymphomas as high grade (small, noncleaved and large cell, immunoblastic-plasmacytoid) and 31% as intermediate grade (diffuse large cell). Each histopathologic category was correlated with distinct clinical features, including a statistically significant difference in median survival. Patients with Hodgkin disease had an atypical, aggressive clinical course, whereas patients with T-cell chronic lymphocytic leukemia had an indolent clinical course. These studies show the clinical, morphologic, and immunophenotypic spectrum of AIDS-associated lymphoid neoplasia, that the natural history of Hodgkin disease is altered in patients with AIDS, and support the Centers For Disease Control's recent revision in diagnostic criteria for AIDS to include intermediate-grade diffuse, aggressive non-Hodgkin lymphomas occurring in patients seropositive for human immunodeficiency virus.