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121.
Objective  As factors that alter the immune system have been implicated in non-Hodgkin lymphoma (NHL) etiology, it is of interest to explore the association between vaccination and risk of NHL. Results of few epidemiologic studies conducted thus far are inconsistent, and only one has examined the association by histologic subtype. Subjects  A population-based, case–control study of 387 patients with NHL and 535 controls conducted in Nebraska between 1999 and 2002. Methods  Information on vaccination for tetanus, polio, influenza, smallpox, and tuberculosis, as well as important environmental factors, was collected by telephone interview. Risk was estimated by odds ratios (ORs) and 95% confidence intervals (CIs), adjusting for confounders. Results  We found that NHL risk was inversely associated with ever receiving a polio (OR = 0.59, CI = 0.40–0.87) or smallpox (OR = 0.71, CI = 0.51–0.98) vaccination, and positively associated with influenza vaccination (OR = 1.53, CI = 1.14–2.06). No significant association was found for tetanus or tuberculosis vaccination. The patterns of association were similar between men and women. Analysis by histologic subtypes showed that polio vaccination was associated with a lower risk of follicular (OR = 0.54, CI = 0.31–0.92) and chronic lymphocytic leukemia/small lymphocytic lymphomas (OR = 0.29, CI = 0.12–0.69) and smallpox vaccination was associated with a lower risk of marginal zone lymphoma (OR = 0.41, CI = 0.19–0.88). In contrast, ever receiving an influenza vaccination was associated with a higher risk of follicular (OR = 1.98, CI = 1.23–3.18) and diffuse large B cell lymphomas (OR = 1.88, CI = 1.13–3.12). Conclusion  Risk of NHL is inversely associated with polio and smallpox vaccination and positively associated with influenza vaccination. These associations appear to differ by histologic subtype. Specific contributions of all authors to published work: HAL provided input into the statistical analyses and drafted and revised this report. BCC designed and oversaw conduct of the epidemiologic case–control study and provided input into the statistical analyses. DDW was responsible for reviewing cases. HAL, AJF, AME, BCC, and DDW provided input into the data analyses and interpretation. All authors contributed to the final version of this report.  相似文献   
122.
Characteristic chromosomal abnormalities are associated with specific histological subtypes of non-Hodgkin lymphoma (NHL). The chromosomal translocation t(14;18)(q32;q21) is one of the most common chromosomal abnormalities in NHL, occurring in 70%-90% of cases of follicular lymphoma, 20%-30% of diffuse large B-cell lymphoma, and 5%-10% of other less common subtypes. The t(14;18)-positive NHL may represent a homogenous group and, consequently, increase etiologic specificity in epidemiological studies. Although the t(14;18) has important clinical ramifications, its etiologic significance remains to be determined. Two population-based, case-control studies addressed this issue by evaluating potential risk factors for t(14;18)-positive and t(14;18)-negative subgroups of NHL. Both studies found that the association between pesticide exposures and risk of NHL was largely limited to t(14;18)-positive NHL cases. However, the findings regarding cigarette smoking, family history of hematopoietic cancer, and hair dye use were not entirely consistent. These results indicate that defining subgroups of NHL according to t(14;18) status may be useful for etiologic research, particularly for exposures that are genotoxic or may contribute to the development of NHL through pathways involving the t(14;18). Studies to further evaluate these associations and delineate the effects of various exposures in other genetically defined subgroups of NHL are warranted.  相似文献   
123.
Some evidence suggests that smoking, a family history of hematopoietic cancer, and use of hair dyes are associated with t(14;18)-defined subsets of non-Hodgkin's lymphoma (NHL) in men. To further evaluate these associations and to expand them to women, the authors determined t(14;18)(q32;q21) status by fluorescence in situ hybridization in 172 of 175 tumor blocks from a population-based case-control study conducted in Nebraska during 1983-1986. Exposures in 65 t(14;18)-positive cases and 107 t(14;18)-negative cases were compared with those among 1,432 controls. Odds ratios and 95% confidence intervals were calculated using polytomous logistic regression. Among men, smoking was not associated with risk of t(14;18)-positive or -negative NHL. Among women who had ever smoked cigarettes, there was an association with risk of t(14;18)-negative NHL (odds ratio (OR) = 1.9, 95% confidence interval (CI): 1.1, 3.3) but not t(14;18)-positive NHL (p-difference = 0.01). The risks for t(14;18)-negative NHL among women increased with longer duration (>30 years: OR = 2.1, 95% CI: 1.1, 4.1) and early initiation (age 相似文献   
124.
Non-Hodgkin lymphoma (NHL) is composed of a heterogeneous collection of subtypes with considerable differences in genetics, biology and aetiology. Studies to date on physical activity and NHL risk have not had sufficient sample size to evaluate whether associations differ by subtype. We pooled data from nine case-control studies to examine the association between moderate-to-vigorous intensity physical activity (MVPA) and risk of NHL overall and by subtype (diffuse large B-cell lymphoma, follicular lymphoma, chronic lymphocytic leukaemia/small lymphocytic lymphoma, marginal zone lymphoma and mature T-cell lymphoma). A total of 5653 cases and 9115 controls were included in the pooled analysis. Physical activity was harmonised across nine studies and modelled as study-specific tertiles. Multinomial logistic regression was used to estimate the association between physical activity and NHL, adjusting for confounders. The overall odds of NHL was 13% lower among participants in the most active tertile of MVPA compared to the least active tertile (adjusted odds ratio = 0.87, 95% CI = 0.80, 0.95). Similar decreases were observed across NHL subtypes. In summary, in this pooled analysis of case-control studies, physical activity was associated with a modest risk reduction for each NHL subtype examined and with overall NHL.  相似文献   
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126.
Successful cytogenetic studies were performed on 69 biopsies from 64 patients with non-Hodgkin's lymphoma bearing a t(14;18)(q32;q21) translocation. This translocation appears to be a primary abnormality associated with the development of certain B-cell non-Hodgkin's lymphomas. We correlated the occurrence of secondary abnormalities, in addition to the t(14;18)(q32;q21), with histologic subtype to test the hypothesis that secondary abnormalities correlate with more aggressive histologic appearance. A large number of secondary abnormalities were identified, the most frequent being additional copies of chromosomes 7 (30%), 12 (22%), 18 (22%), 20 (16%), or 21 (14%), deletion of a portion of the long arm of chromosome 6 (17%), and either an additional chromosome 17 or an isochromosome for the long arm of chromosome 17 (13%). An extra chromosome 7 was highly associated with a diffuse histologic pattern; it was present in 52% of patients with a diffuse pattern and in only 15% of those with a follicular pattern (P = .002). A weaker association with a diffuse growth pattern was found for the addition of chromosome 17 or an i(17q); it was found in 24% of patients with a diffuse pattern and only 5% of those with a follicular pattern (P = .05). No other significant correlations between secondary chromosome abnormalities and histologic subtype were identified. Although the explanation for this association is not clear, it appears that patients with B-cell non-Hodgkin's lymphomas bearing the t(14;18)(q32;q21) translocation which also have an additional chromosome 7 are likely to exhibit a diffuse growth pattern.  相似文献   
127.
PURPOSE: Hodgkin's disease (HD) is a malignancy that displays a bimodal age distribution. Previous reports of treatment in patients greater-than-or-equal 60 years have found a poor outcome, particularly in patients with advanced disease. Because of an improved side-effect profile, the regimen of chlorambucil, vinblastine, procarbazine, and prednisone (ChlVPP) has been proposed for use in elderly patients. PATIENTS AND METHODS: From September 1982 to May 1998, 262 patients with previously untreated HD received either ChlVPP (n = 176) or ChlVPP plus doxorubicin/bleomycin/vincristine (ChlVPP/ABV hybrid; n = 86). Fifty-six patients were greater-than-or-equal 60 years old, and 206 were younger than 60 years. RESULTS: The 5-year overall survival (OS; 87% v 39%) and the 5-year event-free survival (EFS; 75% v 31%) favored patients younger than 60 years of age. Prognostic factors analyzed in patients greater-than-or-equal 60 years of age, other than type of therapy, included sex, stage, Karnofsky performance score, lactic dehydrogenase, number of extranodal sites, B symptoms, size of largest mass, and histologic subtype. In patients older than 60 years, none of the clinical features was a statistically significant predictor of EFS; however, ChlVPP/ABV hybrid was associated with a decreased risk of an event (relative risk, 0.40; 95% confidence interval, 0.19 to 0.83; P =.014) compared with ChlVPP. The 5-year OS for patients greater-than-or-equal 60 years who received ChlVPP was 30%, compared with 67% for those patients receiving the ChlVPP/ABV regimen (P =.0086) CONCLUSION: Patients greater-than-or-equal 60 years with HD who require chemotherapy are better treated with ChlVPP/ABV hybrid than with ChlVPP alone.  相似文献   
128.
Radiography of specimens is an essential step in confirming excision of nonpalpable breast lesions. On occasion, however, the pathologist may not identify the lesion histologically. The authors report five cases in which suspicious microcalcifications were included in the excised tissue but were not identified by the pathologist. In all five, paraffin tissue block radiography enabled identification of the specific blocks containing the microcalcifications. The correct tissue blocks were then sectioned again, and the microcalcifications were identified histopathologically. In one case, the initial diagnosis of intraductal hyperplasia was changed to intraductal carcinoma with focal invasion. When the pathologist cannot identify the calcifications on initial histopathologic sections, this technique may assist in identification of the mammographic abnormality.  相似文献   
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