Chromosomal aberrations in non-Hodgkin's lymphoma. Biologic and clinical correlations

Molecular characterization of chromosomal aberrations in non-Hodgkin's lymphoma (NHL) has provided a basic understanding of mechanisms of oncogene deregulation. Cytogenetic aberrations have been correlated with histologic subtype, immunophenotype, and clinical features of NHL. Although the incomplete specificity of some of the observed associations may limit the routine use of these markers in a clinical setting, the utilization of cytogenetic analysis can contribute to the diagnosis and management of patients with NHL.     

AgNORs predictive value of prognosis in non-Hodgkin's lymphoma: comparison with flow cytometric cell cycle analysis.

Paraffin-embedded histopathologic specimens, taken before the commencement of therapy from 14 low-grade and 21 high-grade malignant lymphoma patients, and 9 normal lymph nodes were utilized to analyze six cell DNA-related parameters. The flow cytometry technique was used to determine cell-cycle G0/G1, S and G2/M phases, and silver staining to enumerate nuclear organized regions (AgNORs); nucleus surface area was determined by an image-analyzing system. The six parameters and natural logarithm of cell proportion in the S-phase (LS) were determined according to the histologic tumor type and achievement of the first complete remission (CR). All parameters except cell proportion in G1/M cycle phase differed significantly with respect to histologic cell type, but were not related to the achievement of first CR. Inasmuch as the parameters significantly correlated with each other, multivariate discriminant analysis and proportional hazard regression were applied to estimate their discriminant/predictive values with respect to tumor malignancy. AgNORs proved to be far superior in all three clinical parameters, S-phase was significantly predictive for the achievement of first CR, and LS for tumor histology type. The statistical model applied narrowed down the analysis of seven parameters to two with respect to tumor histology type (AgNORs and LS) and achievement of first CR (AgNORs and S), but only to one for overall patient survival (AgNORs). Only the model for tumor histology type discrimination was statistically significant (R2 = 0.904, p < 0.001). It appears that AgNORs may be of utmost predictive importance for the clinical outcome in NHL.     

Contribution of 3H-thymidine labelling index and flow cytometric S-phase in predicting survival of patients with non-Hodgkin's lymphoma.

The 3H-thymidine labelling index (3H-dT LI) of cell suspensions from fresh material and the flow cytometric S-phase (FCM-S) of nuclei recovered from paraffin blocks were determined on the same pathologic lymph node specimen for 190 non-Hodgkin's lymphomas (NHLs). FCM-S was defined by a planimetric method and by an optimization procedure. Poor correlation coefficients were observed among the three cell kinetic variables. All three cell kinetic variables were significant indicators of 8-year survival and median survival time. The life-regression procedure evidenced a significant relative contribution of 3H-dT LI and FCM-S, thus suggesting a different biologic meaning of the two cell kinetic variables. This finding was further supported by evidence that simultaneous use of 3H-dT LI and FCM-S can identify groups of patients with different survival better than when either modality is used alone. Multivariate analysis indicated that the risk groups as defined by cell kinetic variables are predictors of survival even in the presence of established factors such as histology and stage.     

Primary gastric non-Hodgkin's lymphoma. A retrospective clinico-pathological study.

Prognostic factors and treatment results were analysed in 72 consecutive patients with primary gastric lymphoma treated between 1970 and 1985. There were 37 patients in stage IE, 17 in IIE, 3 in IIES and 15 in stage IV. Histopathological re-evaluation and classification according to the TNM system were performed. We found that disseminated disease (stage IV), serosal penetration (T3), involvement of adjacent organs (T4) and extensive abdominal lymph node involvement (N3) were poor prognostic factors. Neither histological malignancy grading, nor the appearance of lympho-epithelial lesions were significantly associated with relapse-free survival. Forty-six patients with 'limited localized' disease (stage IE, IIE, N3 excluded) received potentially curative treatment (surgery, radiotherapy, chemotherapy or combinations thereof), of whom 85% remained relapse-free. Thirty-four patients did only get local treatment (surgery and/or radiotherapy) with curative potential, the relapse-free survival rate was 85%. We conclude that primary gastric lymphoma stage IE and IIE (N3 excluded) is often a truly localized disease that can be cured with local therapy.     

Synovial sarcoma. A DNA flow cytometric study

The relationship between DNA content, clinicopathologic findings, and patient survival in synovial sarcoma was investigated. Patient age at diagnosis (P less than 0.001), tumor size (P less than 0.001), and ploidy status (P less than 0.003) correlated significantly with patient survival. A marginally significant correlation between mitotic count and patient survival was also observed (P = 0.04). Histologic subtypes (monophasic versus biphasic), mitotic count, and S-phase by flow cytometry had no significant influence on the clinical outcome of patients with synovial sarcoma in this study. The authors conclude that DNA ploidy analysis is a significant objective probe in the prognostication of patients with synovial sarcoma.     

Flow cytometric DNA analysis: a prognostic tool in non-Hodgkin's lymphoma

Surgical biopsies from 234 untreated patients with non-Hodgkin's lymphoma (NHL), classified according to the Kiel nomenclature, were analysed with respect to proliferative activity (S-phase) and DNA content by flow cytofluorometric (FCF-DNA) analysis. The percentage of cells in S-phase was significantly higher in lymphomas of high compared to low grade NHL (p less than 0.001). Patients with lymphomas of high grade histology and low S-phase values (less than 5.6%) achieved complete remission (CR) more often (p less than 0.05) and survived significantly longer than those with high S-phase values (p less than 0.05). In the low grade NHL group the S-phase value did not correlate to response. S-phase correlated to survival for patients with the lymphocytic (CLL & IC) (p less than 0.05) and follicle center cell (FCC) derived (p less than 0.01) but not in blastic (LB, IB, Burkitt) NHL. DNA-aneuploidy was associated with poor response to therapy and shorter CR duration in low grade NHL (p less than 0.05 for both). However, the degree of DNA-ploidy (neardiploid or aneuploid) did not correlate to survival in any of the NHL groups analysed (high- or low grade, lymphocytic, FCC derived or blastic). The Cox regression analysis indicated that the S-phase value was a stronger predictor of survival than histopathology, stage or age, especially in low grade NHL. These results suggest that S-phase analysis should be included in the clinical evaluation of NHL patients as a prognostic indicator.     

A clinicopathologic study of orbital and adnexal non-Hodgkin's lymphoma.

An analysis of non-Hodgkin's lymphoma involving the orbital structures was performed at the University of Iowa between 1937 and 1975. Sixteen cases of primary orbital lymphoma were diagnosed. Histopathologic reclassification according to the Rappaport scheme and the clinical course of each histologic sub-category was described. There were 5 patients with reactive hyperplasia, 2 patients with well-differentiated lymphoid proliferation with Dutcher bodies which were also felt to be reactive, 3 patients with diffuse poorly differentiated lymphocytic lymphoma, 4 patients with nodular poorly differentiated lymphocytic lymphoma, and 2 patients with diffuse histiocytic lymphoma. It was concluded that the Rappaport classification is applicable to orbital lymphoid tumors and that those lymphomas which do present as primary tumors should be staged as one would stage the same histologic category of lymphoma presenting in other sites. Radiation therapy appears to be an effective treatment for local control; however, patients with primary orbital lymphoma should undergo observation for systemic disease similar to patients with lymphoma presenting in other sites. Excisional biopsy is recommended to facilitate precise classification.     

A histologic and flow cytometric study of Kaposi's sarcoma.

One hundred forty-three biopsies of Kaposi's sarcoma (KS) from 96 patients were assessed histopathologically, and mitoses were counted. Ninety-seven samples from 66 patients were analyzed by flow cytometry. Six of 97 (5.8%) KS lesions were DNA aneuploid with a clustering around a DNA index of 1.5 (range, 1.4 to 1.6). The median percentage of S-phase plus G2-phase cells (%S + G2) was 16.7%. Increasing mitotic counts and %S + G2 were seen with progression of the phase and pattern of disease. Nodular KS and spindle cell predominant KS had the highest mitotic counts and %S + G2, with nodular KS larger than 4 mm having a higher mitotic count than those smaller than 4 mm. These findings suggest a low level of DNA aneuploidy in KS and important changes in the level of cell proliferation with the phase and pattern of the disease. However, flow cytometry does not solve the dilemma of whether KS is a hyperplastic or neoplastic process.     

Multilobated non-Hodgkin's lymphoma. A clinicopathologic entity

Multilobated non-Hodgkin's lymphomas (NHL) have recently been recognized as an NHL variant. During a period of 10 years we observed 30 individuals with NHL in which more than 30% of the malignant cells had a characteristic multilobation. The immunologic phenotype was determined in 14 of these cases. One was of T-cell lineage, and the others exhibited B-lymphoid markers. Sixty-eight percent of the patients presented with extranodal localizations. In the clinical follow-up a complete remission was observed in 78% of patients with a mean duration of 37 months (range, 5 to 120 months). The actuarial survival after 5 years was 45%. From these data we conclude that multilobated NHL are comparable to diffuse, large cleaved-cell NHL of an intermediate grade malignancy according to the Working Formulation or are comparable to the diffuse centrocytic-centroblastic NHL according to the Kiel classification. The neoplastic cells are to be considered as variants of follicle center cells, but the clinicopathologic correlation indicates that multilobated NHL represent a distinct nosologic entity.     

Biologic therapy for lymphoma.

Biologic approaches to lymphoma treatment are now a practical reality rather than a vaguely perceived hope for the future. Interferon alfa seems to have been established as a life-extending therapy for selected patients with follicular lymphoma. Humanized anti-CD20 monoclonal antibody (rituximab) has an authentic 50% response rate in patients with follicular lymphoma, frequently works when given a second time, and is demonstrating what seems to be synergistic activity when combined with chemotherapy. Radioimmunoconjugates using iodine-131 and yttrium-90 as payload are producing responses in refractory and aggressive lymphomas. Vaccines and adoptive cellular therapies are also showing promising results in early phase clinical testing.     

Flow cytometric light chain analysis of peripheral blood lymphocytes in patients with non-Hodgkin's lymphoma

Peripheral blood lymphocytes from 96 patients with non-Hodgkin's lymphoma were studied, either at primary staging, during treatment or in follow up. The amount of surface immunoglobulin light chain per cell was determined by direct immunofluorescence staining analysed by flow cytometry. Discrepancy between kappa and lambda fluorescence profiles in the sample was considered to indicate the presence of monoclonal cells i.e., circulating lymphoma cells. The results were correlated with routine haematological findings, histopathology of the lymphoma and tumour burden. Using routine haematological methods leukaemic spread was evident in 24% of the patients in our study. Using kappa/lambda distribution analysis evidence of circulating lymphoma cells was found in an additional 27%. As expected, the major diagnostic gain was in the low grade malignant group, where 30% of the patients with normal peripheral blood according to standard procedures showed evidence of circulating lymphoma cells in the kappa/lambda distribution analysis. The corresponding gain in the high grade malignant group was 19%. In patients with active disease but without morphological evidence of leukaemia, 37% showed abnormal kappa/lambda distributions. In patients in complete remission the corresponding figure was 18%. The clinical significance of small numbers of circulating lymphoma cells is not yet understood, but a possible outlook is to use kappa/lambda distribution analysis to increase staging precision and in the early detection of relapse.     

Cytogenetic progression and prognosis in oral-carcinoma - a DNA flow cytometric study on 317 cases

A total number of 317 consecutive patients with squamous cell carcinoma of the oral cavity were analysed by DNA flow cytometry. The proportion of tumors consisting exclusively of diploid cells decreased from 75% in T1G1 carcinomas to less than 10% in advanced tumors in favor of cases characterized by the presence of cell lines with aberrant DNA content. This observation indicates a genetic evolution of tumor clones with severe karyotype aberrations from diploid progenitors which obviously represents an ultimate event in the pathogenesis of oral carcinomas. Aneuploidy formation clearly contributes to the acquisition of progressive malignant behaviour as is underlined by a dramatic difference of the survival outcome of patients with diploid tumors (5-year overall survival: 88%) as compared to those who had aneuploid tumors (36%; P<0.001), a relationship which held true even if identical tumor stages were considered. There were no indications of successive genetic changes of the cellular DNA contents during tumor progression which would explain the wide range of variation of the individual DNA values. This observation supports the hypothesis of an aneuploidy formation by a single cytogenetic event, such as an abnormal mitosis. Although there were indications of an even worse survival outcome in the group of patients with peri-diploid tumor cell lines (P<0.1), a significant influence of different DNA contents on the prognosis could not be detected.     

MACOP-B regimen in non-Hodgkin's lymphoma.

Two university centers in Finland used MACOP-B regimen as first-line treatment of intermediate and high-grade non-Hodgkin's lymphomas in 1986-1990. The clinical records of all 41 patients treated with this regimen were analyzed. The median age was 47 years (range 16-65), 24% of the patients had WHO performance status > 1, 49% had B-symptoms, 46% had Ann Arbor stage III or IV disease, and 39% had bulky disease. Twenty-three (58%) of the 40 patients who were evaluable for response had CR. The survival rate 36 months after the start of MACOP-B was 62%, but failure-free survival rate only 36%. Among several analyzed factors a lactate dehydrogenase level < 500 U/l before treatment showed the strongest association to failure-free survival. The planned dose intensity was not achieved mainly because of toxicity, and the ratio of the actual dose intensity given to the planned dose intensity varied for the different drugs between 0.77 and 0.92.     

Prognostic factors in non-Hodgkin's lymphoma.

There is an emerging consensus on the importance of identifying non-Hodgkin's lymphoma patients with different prognoses so that these patients can be optimally treated and the relative benefits of different therapeutic approaches can be adequately assessed. This review of recent publications on prognostic factors in lymphoma will summarize papers identifying: 1) clinical features associated with prognosis in specific subgroups of lymphoma patients; 2) the prognostic significance of pathologic and immunologic subclassification; 3) prognostic features predictive for relapse from complete response; and 4) newly identified prognostic features, including cytogenetic abnormalities, serologic parameters, and aberrant expression of adhesion molecules.     

Recent progress in non-Hodgkin's lymphoma study in Japan

Great progress has been made in clinical research on non-Hodgkin's lymphoma during the last 15 years. Surface marker and DNA analyses of immunoglobulin and T-cell receptor genes are essential for new classification of the disease according to the cellular origin of tumor cells. This approach resulted in the establishment of new disease entities such as adult T-cell leukemia/lymphoma(ATL), immunoblastic lymphoadenopathy (IBL)-like T-cell lymphoma, and the pleural B-lymphoma occurring in long-standing pyothorax. New retrovirus, HTLV-I, was found during studies on ATL. Prevention of HTLV-I infection is an important project. HTLV-I negative ATL was also found and is of particular interest in understanding leukemogenesis of ATL. An oncogen such as bcl-2 is important for characterization of follicular lymphoma. Prognostic factors of patients with T-lymphoma are completely different from those of B-lymphoma. Risk grouping by combination of major prognostic factors is useful for the selection of the best treatment modality and the accurate estimation of prognosis of patients at initial presentation. The effect of combination chemotherapy should be evaluated separately between T- and B-lymphomas because of the difference in response rate and prognostic factors.