Primary mediastinal large B-cell lymphoma: a clinicopathologic study of 43 patients from the Nebraska Lymphoma Study Group.

PURPOSE: To investigate whether primary mediastinal large B-cell lymphoma (PMLBL) is a distinct clinicopathologic entity with a more aggressive course than other diffuse large B-cell lymphomas (DLBL). MATERIALS AND METHODS: All patients with CD20-positive DLBL who presented with a mediastinal mass measuring at least 5.0 cm and were treated with curative intent were identified. A control group of 352 patients with nonmediastinal DLBL was selected for comparison. RESULTS: The 43 patients with PMLBL had a male to female ratio of 20:23 and a median age of 42 years. Stage I/II disease was present in 58% of the patients, with only 9% having bone marrow involvement. A complete remission was achieved in 63% of the patients, and the 5-year overall and failure-free survivals were 46% and 38%, respectively. Among the clinical variables, an elevated serum lactate dehydrogenase level, a low performance score, more than one extranodal site, and an intermediate or high International Prognostic Index score were predictive of poor survival. When compared with the DLBL group, a younger median age was the only clinical feature that was significantly different in the PMLBL group. CONCLUSION: The clinical features of PMLBL do not appear to be significantly different from those of nonmediastinal DLBL. Although the younger age of onset, slight female predominance, mediastinal location, and size of the mass may justify the recognition of PMLBL as a clinical syndrome, additional evidence is needed to define it as a distinct disease entity.

Occurrence of the t(2;5)(p23;q35) in non-Hodgkin's lymphoma.

Primary CD30(Ki-1)-positive anaplastic large-cell lymphoma (ALCL) is considered by some to be a distinct clinicopathologic entity associated with the t(2;5) (p23;q35). However, the specificity of t(2;5) for ALCL has not been carefully studied. Therefore, we performed a detailed analysis of all cases of ALCL with abnormal cytogenetics results in the Nebraska Lymphoma Study Group registry, as well as all other cases of non-Hodgkin's lymphoma with t(2;5) in the registry. We found the t(2;5) in only five of 10 cases of ALCL, four of whom were young patients. However, we also found the t(2;5) in 11 other cases of nonanaplastic lymphoma, including eight children with typical peripheral T-cell lymphomas of various types. The t(2;5) was also found in three older adults with B-cell lymphomas of various types. Thus, the t(2;5) was not specific for CD30+ ALCL. However, t(2;5) may define a clinicopathologic entity in children and young adults characterized by variable morphologies with a T-cell or indeterminate phenotype, CD30-positivity, nodal disease with frequent extranodal involvement, advanced stage, and an excellent response to therapy, including bone marrow transplantation for relapsed disease. The clinical relevance of the t(2;5) in older patients requires further study.

Lymphomatous polyposis. A neoplasm of either follicular mantle or germinal center cell origin.

Lymphomatous polyposis (LP) is generally thought to be an expression of non-Hodgkin's lymphoma (NHL) of follicular mantle cell (MC) origin. We report nine patients with LP from more than 3,500 cases of NHL studied by the Nebraska Lymphoma Study Group. Our patients differed from those reported previously in that LP represented a follicular center cell (FCC) NHL in two of the nine cases, with the remainder consisting of MC NHL. Three patients developed LP during a relapse of previously diagnosed and treated extraintestinal MC NHL (parotid gland, tonsil, and inguinal lymph node, respectively), whereas the other six patients presented with primary LP. In seven of the nine LP cases, a large mass predominated among a myriad of small polyps. The FCC cases were confined to the small intestine, whereas the MC cases were either pan-intestinal or colonic on their localization. Two MC cases studied by Southern blotting exhibited rearrangement of the bcl-1 locus. Bcl-2 rearrangement was not detected in any of the nine cases when studied by either a polymerase chain reaction-based assay (seven cases) or by Southern blotting (two cases). To date, four patients (three MC, one FCC) have experienced recurrent NHL in gastrointestinal sites. With follow-up ranging from 13 to 147 months, the entire group had a median survival of 41 months (primary MC LP:13, 13, 41, and 77 months; primary FCC LP:45 and 147 months; secondary MC LP:17, 41 and 76 months), and only one patient has died. We conclude that LP is a rare manifestation of NHL of either follicular MC or germinal center cell origin.

Clinical and prognostic significance of bone marrow involvement in patients with diffuse aggressive B-cell lymphoma.

PURPOSE: We studied the effect of morphology and extent of bone marrow (BM) infiltrate on the survival of patients with diffuse aggressive B-cell non-Hodgkin's lymphoma (NHL), along with clinical features. PATIENTS AND METHODS: Sixty adult patients with diffuse aggressive B-cell NHL and BM involvement at the time of presentation were studied. All patients were uniformly staged and treated with a curative high-dose chemotherapy regimen. BM involvement was assessed according to the cytology, pattern of infiltration, and extent of involvement, and was correlated with overall survival (OS) and failure-free survival (FFS). RESULTS: Patients with BM involvement that consisted of > or = 50% large cells or BM involvement of > or = 70% had a poorer OS (P = .065 and P = .055, respectively). Those who presented with an infiltrate of less than 50% large cells and an international prognostic index (IPI) of < or = 3 had a significantly longer postrelapse survival time (P = .003). A diffuse or interstitial pattern of BM involvement was predictive of both poor OS and FFS (P = .008 and .009, respectively). Multivariate analysis indicated that only IPI (P = .0005) and pattern of BM infiltration (P = .009) were independent predictors of OS, and only the former was predictive of FFS (P = .03). CONCLUSION: The IPI is predictive of OS and FFS, while BM involvement with a diffuse or interstitial pattern is associated with significantly poorer OS. Patients with BM infiltration that involved > or = 70% of the marrow or contained > or = 50% large cells had poor OS, but more patients need to be studied to determine the significance. Two parameters, IPI < or = 3 and BM large cells less than 50%, identify a group of patients with long-term survival after relapse.

Prognostic value of cellular proliferation and histologic grade in follicular lymphoma.

The clinical usefulness of histologic grading in follicular lymphoma (FL) is controversial and is further compromised by the subjective nature and poor reproducibility of most systems in current use. Therefore, we decided to objectively evaluate the importance of cellular proliferation in FL, along with the current grading systems. We studied 106 patients with FL who were uniformly staged and aggressively treated. A proliferative index (PI) was determined quantitatively using an automated image analyzer and a new Ki-67 antibody that stains archival paraffin tissues. The cases were also subclassified according to the Berard, Rappaport, Luke-Collins, and Jaffe methods, and survival analysis was performed. Patients with a low PI (< 40%) had a significantly longer overall survival (OS) than those with a high PI (> or = 40%), but the PI did not predict failure-free survival (FFS). The mean PI correlated well with the subgroups in each of the various classifications. All four of the classification methods were predictive of OS, but only the Berard method appeared to predict FFS and suggest that a proportion of patients with FL may be curable. In multivariate analysis, histologic classification was the only independent predictor of OS (Berard method: relative risk, 3.1) and the International Prognostic Index was the only independent predictor of FFS (relative risk, 2.3). We conclude that the Berard method for grading of FL is clinically useful and, along with the International Prognostic Index, should be included in future clinical studies of FL. The measurement of cellular proliferation does not appear to add additional useful information in FL.

The role of high-dose therapy and autologous hematopoietic stem cell transplantation for mantle cell lymphoma.

BACKGROUND: Although mantle cell lymphoma (MCL) is a distinct disease entity with well described clinical and pathological features, little information exists regarding its therapy. This paper will evaluate patients with MCL receiving either induction therapy with an anthracycline or high-dose chemotherapy and autologous hematopoietic stem cell transplantation for relapsed disease. PATIENTS AND METHODS: The cases of 14 previously untreated patients with MCL who received an anthracycline-containing combination chemotherapy regimen on Nebraska Lymphoma Study Group protocols from 3/83 to 2/92 were reviewed. During the same time period, a different set of nine patients with recurrent MCL were referred for high-dose chemoradiotherapy and autologous stem cell rescue as salvage therapy. RESULTS: The five year overall (OS) and failure-free (FFS) survivals from the initiation of chemotherapy for the patients receiving an induction therapy with an anthracycline containing regimen were 23% and 8%, respectively. At the time of this analysis, three of the nine transplant patients remain progression-free 7, 12, and 25 months post-transplant. Two year overall and FFS for all nine patients was 34%. CONCLUSIONS: Longer follow-up of greater patient numbers is required to determine whether high-dose therapy can overcome the chemoresistance and increase the cure rate of MCL. Since most patients with this disease have minimal chance of cure with standard chemotherapy, the optimal timing for high dose therapy may be as part of front-line treatment. Further clinical trials are required to investigate the potential benefits of high-dose therapy for patients with MCL.

Cytogenetic abnormalities in B-immunoblastic lymphoma.

We have considered the cytogenetic abnormalities present in 27 unpublished cases of B-immunoblastic lymphoma. Among these 27 patients, the chromosome changes were heterogeneous and complex. The chromosomes most commonly gained were 3 (44% of cases), 18 (44%), 6 (30%) and 11 (30%). The most common structural abnormalities involved band 14q32 (26%), band 18q21 (15%) and bands 6q16-21 (19%). Study of these 27 immunoblastic lymphomas did not allow us to tentatively identify a common primary cytogenetic abnormality unique to B-immunoblastic lymphoma, however, a translocation at 14q32 may be the primary cytogenetic lesion in some of the cases. Rather, we have added to the number of abnormalities reported in immunoblastic lymphoma and in non-Hodgkin's lymphoma in general.

Prognostic significance of clinical and pathologic features in diffuse large B-cell lymphoma.

BACKGROUND AND METHODS: The diffuse large cell non-Hodgkin lymphomas are a heterogeneous group of neoplasms that are potentially curable. To identify important predictors of clinical outcome, the authors evaluated the clinical and pathologic features of 114 patients with newly diagnosed diffuse large B-cell lymphoma who were uniformly staged and treated with curative intent. The authors were particularly interested in determining whether any pathologic features added to the ability of the clinical features to predict patient survival. RESULTS: Several clinical and pathologic features were found to be associated with survival by univariate analysis. However, multivariate analysis disclosed that only the stage of disease and the symptom status were significantly associated with survival. Low stage and lack of B symptoms were favorable indicators of overall survival and failure-free survival. CONCLUSIONS: The authors suggest that the evaluation of pathologic features in diffuse large B-cell lymphoma has little prognostic utility and recommend that the pathology evaluation be limited to features that are useful for diagnostic purposes.

Histologic grade does not predict prognosis in optimally treated, advanced-stage nodular sclerosing Hodgkin's disease.

Forty-two patients with advanced-stage nodular sclerosing Hodgkin's disease (NSHD) were treated uniformly with combination chemotherapy and radiation therapy at the University of Nebraska Medical Center between 1982 and 1987. The cases were subclassified into low-grade (13 cases) and high-grade (29 cases) categories using the British National Lymphoma Investigation (BNLI) histologic criteria. After a median follow-up interval of 48 months, no significant differences with regard to the complete remission rate (100% versus 90%), remission durability (85% versus 96%), or predicted 4-year actuarial survival (92% versus 86%) were observed between the two groups, respectively. It was concluded that the BNLI grading scheme for NSHD does not predict the clinical outcome of patients with advanced-stage NSHD who receive optimal therapy.

Immunoblastic lymphoma with abundant clear cytoplasm. A comparative study of B- and T-cell types.

The morphologic, phenotypic, molecular genetic, and clinical features of 34 cases of clear-cell immunoblastic lymphoma (IBLC) are described. Sixteen cases were of B-cell type (IBLC-B) and 18 cases were of T-cell type (IBLC-T). There were no significant differences in the morphologic characteristics of the neoplastic cells in the two types, although IBLC-B was less likely to be polymorphic than IBLC-T. Interfollicular proliferation, a higher mitotic rate, infiltration by eosinophils, and an increase in capillary-sized blood vessels were also features of IBLC-T, whereas necrosis and fibrosis were more extensive in IBLC-B. Patients with IBLC-B were predominantly female, whereas those with IBLC-T were predominantly male. The mean age was 62 years for those with IBLC-B and 46 years for those with IBLC-T. Patients with IBLC-B usually had lower-stage disease, but there was no significant difference in survival rate between those with IBLC-B and those with IBLC-T. Although most cases of IBLC have been considered to be of peripheral T-cell origin, the authors conclude that IBLC-B is more common than previously considered and that clear-cell morphologic characteristics are not a reliable indicator of T-cell type.

Diffuse intermediate lymphocytic lymphoma. A clinicopathologic study and comparison with small lymphocytic lymphoma and diffuse small cleaved cell lymphoma.

Controversy has recently arisen as to whether diffuse intermediate lymphocytic lymphoma (ILL) should be considered a low-grade or an intermediate-grade non-Hodgkin's lymphoma for clinical purposes. Therefore, the authors performed a clinicopathologic study to determine the biologic course of diffuse ILL (40 cases) and compared it with small lymphocytic lymphoma (SLL; 51 cases) and diffuse small cleaved cell lymphoma (DSCCL; 14 cases). They found that patients with diffuse ILL having pseudofollicular proliferation centers (PC) had a significantly longer median survival (84 months) than those without PC (46.5 months; P = 0.03). The median survival of patients with SLL was 72 months, whereas those with DSCCL had a median survival of only 18 months. Based on these findings, the authors conclude that diffuse ILL with PC should be included in the low-grade category of SLL for clinical purposes, whereas diffuse ILL without PC (true diffuse ILL) should be considered an intermediate-grade non-Hodgkin's lymphoma. True diffuse ILL is similar to centrocytic lymphoma in the Kiel classification and should be accorded a similar status in a modified Working Formulation.

Mantle zone lymphoma. A clinicopathologic study of 22 cases.

A clinicopathologic analysis of 22 cases of mantle zone lymphoma (MZL) was performed. In lymph node sections, MZL was characterized by the proliferation of neoplastic small lymphoid cells in wide mantles around benign germinal centers. Eighteen cases were of the intermediate lymphocytic type and four cases were of the small lymphocytic type. Immunohistologic analysis of paraffin sections revealed the following characteristic immunophenotype of MZL: L26, LN2, NUB1 and T2/48 positive, and LN5, LN1, AF6 and UCHL1 negative. The immunophenotype of MZL was identical to that of normal primary lymphoid follicles and the mantle zones of secondary follicles, except for the absence of staining with LN5 in MZL. The median age of the patients was 63 years, and the male-to-female ratio was 1.2:1. B symptoms were present in 55% of the patients, and 81% had splenomegaly. An absolute lymphocytosis was present at the time of initial diagnosis in 13% of the patients, and 67% had bone marrow involvement by lymphoma. Thirteen percent of the patients had Stage II disease, 23% had Stage III disease, and 64% had Stage IV disease. All 22 patients received some form of therapy, with 73% receiving multiagent chemotherapy. Eleven patients achieved a complete remission at some time during their course. The overall median survival of the entire group was 88 months. Clinical features which appeared to influence survival adversely included an absolute lymphocyte count above 4000/microliters, a platelet count less than 100,000/microliters, and male sex. Achievement of a complete remission at any time favorably influenced survival. Pathologic features which appeared to influence survival adversely were a mitotic rate of 10 or more per 10 high-power fields (HPF) and the presence of 40 or more large lymphoid cells per 10 HPF. These findings lead the authors to conclude that MZL is a distinctive form of low-grade non-Hodgkin's lymphoma.