Is cigarette smoking a risk factor for non-Hodgkin's lymphoma or multiple myeloma? Results from the Lutheran Brotherhood Cohort Study

Aspirin and risk of multiple myeloma in adults: A systematic review and meta-analysis

Multiple myeloma is a relatively uncommon plasma cell malignancy. Preclinical and clinical studies have suggested that aspirin might modify the risk of multiple myeloma. We performed a systematic review and meta-analysis of studies to examine the association between regular aspirin use and risk of multiple myeloma. Five observational studies including 332,660 adults were evaluated. The pooled estimate had a hazard ratio of 0.90 (95% confidence interval =0.58−1.39; P=0.638). Odds ratios from the two case-control studies were similar. The findings demonstrated that there was no significant association between aspirin use and the risk of multiple myeloma.

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This is a systematic review of aspirin use on the incidence risk of multiple myeloma.

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There is no evidence that aspirin modifies the risk of multiple myeloma.

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More studies are needed to assess the impact of aspirin on the risk of multiple myeloma.

Risk of multiple myeloma in a case-spouse study

This study examined lifestyle, occupation, medical history and medication use with multiple myeloma risk in a case-spouse study (481 patients, 351 spouses). Odds ratios (ORs) and 95% confidence intervals (CI) were calculated using logistic regression. Compared to spouse controls, cases were more likely to have a family history of multiple myeloma (OR = 2.8, 95% CI = 1.2-6.4) and smoked cigarettes (OR = 1.7, 95% CI = 1.2-2.5), but less likely to have consumed alcohol (OR = 0.6, 95% CI = 0.4-0.9). Nurse/health practitioners (OR = 2.8, 95% CI = 1.3-6.2) and production workers (OR = 3.7, 95% CI = 1.0-13.7) had significantly increased risks; and some occupations linked to diesel exhaust had elevated, but non-significant, risks. History of herpes simplex (OR = 1.7, 95% CI = 1.2-2.4), shingles (OR = 1.7, 95% CI = 1.1-2.7), sexually transmitted diseases (OR = 2.0, 95% CI = 1.0-3.7) and medication allergies (OR = 1.7, 95% CI = 1.2-2.4) were associated with higher risks. Use of angiotensin-converting enzyme inhibitors, anti-convulsants, antidepressants, statins and diuretics were associated with reduced risks. The results are consistent with previous population-based studies and support the utility of patient databanks and spouse controls as a resource in epidemiologic research.

Comparison between presence of epstein barr virus in nodal and extra nodal diffuse large B cell lymphoma of head and neck, an Iranian experience

Background

Epstein Barr Virus (EBV) is one of the most common viral infections in human population. EBV has a significant role in pathogenesis of Hodgkin's lymphoma, Burkitt's lymphoma and nasopharyngeal carcinoma. The role of EBV in non-Hodgkin’s lymphoma, diffuse large B cell (NHL - DLBL) in the head and neck is controversial.

Objectives

The purpose of this study is to find out the difference between the presence of Epstein Barr virus in nodal and extra nodal lymphoma of head and neck.

Patients and Methods

A total of 30 cases of DLBL in two separate groups were collected from pathology department. The first group was consisted of 15 patients with DLBL of neck lymph node and the other was consisted of 15 patients with extra nodal DLBL of head and neck mainly in palatine tonsil. Both immune-histo-chemical (IHC) study and polymerase chain reaction (PCR) for detection of late membrane antigen (LMP) were performed on formalin fixed paraffin embedded tissue.

Results

All 30 cases were negative for EBV in IHC method. But in PCR method, 10% of patients were positive for LMP gene. There were 2 positive cases in nodal lymphoma and 1 positive case in extra nodal lymphoma group.

Conclusions

Compare with PCR method, it seems that IHC is not a sensitive method for detection of EBV. Overall, the finding of EBV in NHL depends on site, type of lymphoma and the detection method.

The Relationship between Exposure to Pesticides and the Occurrence of Lymphoid Neoplasm

BACKGROUND

The etiology of malignant lymphoma is still largely unknown. This study determines the relationship between exposure to pesticides and the occurrence of lymphoid neoplasms in Shiraz, Southern Iran.

METHODS

Between 2007 and 2008, in a case control study conducted in Nemazee Hospital in Shiraz, Southern Iran, 200 subjects diagnosed with lymphoma according to the World Health Organization (WHO) classification were enrolled. Controls (n=200) were frequency matched to the cases by sex, age, and center. Subjects who were a farmer were compared with all other occupations.

RESULTS

Out of the 200 cases that were diagnosed as lymphoid neoplasms, 100 were non-Hodgkin's lymphoma, 54 Hodgkin's lymphoma and 46 multiple myeloma. Seventy two percent of the NHL's were of the B-cell type, 15% of the T-cell type and the rest were not classified. Furthermore, subjects exposed to pesticides were at an increased risk of non-Hodgkin lymphoma and MM, but not Hodgkin lymphoma.

CONCLUSION

Risk of non-Hodgkin lymphoma and MM was highest for exposure to pesticides, among them, insecticide's risk was confirmed.

Genetic variation in N-acetyltransferases 1 and 2, cigarette smoking, and risk of non-Hodgkin lymphoma

Cigarette smoke contains many carcinogens that are metabolically activated through xenobiotic metabolism by phase I and II enzymes, including N-acetyltransferases 1 and 2 (NAT1 and NAT2). We investigated non-Hodgkin lymphoma risk in general and by subtype in relation to NAT1 and NAT2 genotypes and cigarette smoking in a population-based case-control study in Connecticut. Of the 535 controls, 53.1% reported ever smoking, and of the 461 cases, 55.7% reported ever smoking. We found a two-fold increased risk of T-cell lymphoma among those possessing the NAT1*10 genotype compared to those with other NAT1 genotypes; including an OR of 2.0 (95% CI: 1.0-2.4) for those heterozygous or homozygous for NAT1*10 genotypes. Rapid acetylator NAT2 phenotype increased the risk of both T-cell lymphoma (OR = 3.2; 95% CI: 1.1-9.5) and marginal zone lymphoma (OR = 3.0; 95% CI: 1.0-8.7), though these results were based on a small number of cases. When smoking status and risk of NHL was stratified by NAT1 and NAT2 genotypes, an increased risk of NHL overall was observed in current (OR = 1.7; 95% CI: 1.2-2.4) smokers without the NAT1*10 genotype but not among smokers with the NAT1*10 genotype (p-interaction < 0.01). No association between history of cigarette smoking and risk of NHL overall was observed with any NAT2 genotype. Our results present modest evidence that acetylation rate is associated with risk of NHL for specific subtypes and that the NAT1*10 genotype is an "at-risk" allele. Additionally, our results suggest that the relationship between NHL and smoking status may be modified by common genetic variation in NAT1 but not NAT2. We conclude that these findings require replication in larger studies and ultimately in pooled analyses.

Clustering of cancer among families of cases with Hodgkin Lymphoma (HL), Multiple Myeloma (MM), Non-Hodgkin's Lymphoma (NHL), Soft Tissue Sarcoma (STS) and control subjects

Background

A positive family history of chronic diseases including cancer can be used as an index of genetic and shared environmental influences. The tumours studied have several putative risk factors in common including occupational exposure to certain pesticides and a positive family history of cancer.

Methods

We conducted population-based studies of Hodgkin lymphoma (HL), Multiple Myeloma (MM), non-Hodgkin's Lymphoma (NHL), and Soft Tissue Sarcoma (STS) among male incident case and control subjects in six Canadian provinces. The postal questionnaire was used to collect personal demographic data, a medical history, a lifetime occupational history, smoking pattern, and the information on family history of cancer. The family history of cancer was restricted to first degree relatives and included relationship to the index subjects and the types of tumours diagnosed among relatives. The information was collected on 1528 cases (HL (n = 316), MM (n = 342), NHL (n = 513), STS (n = 357)) and 1506 age ± 2 years and province of residence matched control subjects. Conditional logistic regression analyses adjusted for the matching variables were conducted.

Results

We found that most families were cancer free, and a minority included two or more affected relatives. HL [(OR_adj (95% CI) 1.79 (1.33, 2.42)], MM (1.38(1.07, 1.78)), NHL (1.43 (1.15, 1.77)), and STS cases (1.30(1.00, 1.68)) had higher incidence of cancer if any first degree relative was affected with cancer compared to control families. Constructing mutually exclusive categories combining "family history of cancer" (yes, no) and "pesticide exposure ≥10 hours per year" (yes, no) indicated that a positive family history was important for HL (2.25(1.61, 3.15)), and for the combination of the two exposures increased risk for MM (1.69(1.14,2.51)). Also, a positive family history of cancer both with (1.72 (1.21, 2.45)) and without pesticide exposure (1.43(1.12, 1.83)) increased risk of NHL.

Conclusion

HL, MM, NHL, and STS cases had higher incidence of cancer if any first degree relative affected with cancer compared to control families. A positive family history of cancer and/or shared environmental exposure to agricultural chemicals play an important role in the development of cancer.

Epidemiology of the plasma-cell disorders

This review of the plasma-cell disorders begins with the definition of monoclonal gammopathy of undetermined significance (MGUS). The prevalence of MGUS in white and black populations is described. MGUS is a common finding in the medical practice of all physicians, and thus it is important to both the patient and the physician to determine whether the monoclonal protein remains stable or progresses to multiple myeloma (MM), Waldenström's macroglobulinemia (WM), primary systemic amyloidosis (AL), or a related disorder. The long-term (almost 40 years) follow-up data of 241 patients in the Mayo Clinic population is provided. In a large study of 1384 patients with MGUS from southeastern Minnesota, the risk of progression to MM, WM, AL, or other disorders was approximately 1% per year. Risk factors for progression are provided. The incidence of MM in Olmsted County, Minnesota, remained stable for the 56-year span 1945-2001. The apparent increase in incidence and mortality rates among patients with MM in many studies is due to improved case ascertainment, especially among the elderly. The incidence and mortality rates of MM in the United States and other countries are presented. The major emphasis is on the cause of MM, which is unclear. Exposure to radiation from atomic bombs, therapeutic and diagnostic radiation, and in workers in the nuclear industry field are addressed. Many studies involving agricultural occupations, exposure to benzene, petroleum products, and engine exhaust and other industrial exposures are discussed. Tobacco use, obesity, diet, and alcohol ingestion are all possible causes of MM. Clusters of MM have been noted. Multiple cases of MM have been found in first-degree relatives.

The non-Hodgkin lymphomas: a review of the epidemiologic literature

The non-Hodgkin lymphomas (NHL) are a heterogeneous group of B-cell and T-cell neoplasms that arise primarily in the lymph nodes. NHL incidence rates in the US doubled between about 1970 and 1990, and stabilized during the 1990s. NHL accounts for approximately 3.4% of cancer deaths in the US. Although some of the observed patterns in NHL have been related to HIV/AIDS, these conditions cannot fully explain the magnitude of the changes; neither do changes in classification systems nor improved diagnostic capabilities. Studies of occupational and environmental exposures (e.g., pesticides, solvents) have produced no consistent pattern of significant positive associations. Inverse associations with ultraviolet radiation exposure and alcohol and fish intake, and positive associations with meat and saturated fat intake have been reported in several studies; additional studies are needed to confirm or refute these associations. Family history of NHL or other hematolympho-proliferative cancers and personal history of several autoimmune disorders are associated with increased risk of NHL, but are not likely to account for a large proportion of cases. HIV and other infectious agents, such as human herpesvirus 8 and Epstein-Barr, appear to be associated with differing types of NHL, such as some B-cell lymphomas. Future epidemiologic studies should evaluate associations by NHL type, enhance exposure information collected, and elucidate factors that may identify susceptible (or resistant) subpopulations because of genetic, immunologic or other characteristics. The extent to which the etiology of NHL types may differ is important to resolve in ongoing and future studies.

Multiple myeloma: A review of the epidemiologic literature

Multiple myeloma, a neoplasm of plasma cells, accounts for approximately approximately 15% of lymphatohematopoietic cancers (LHC) and 2% of all cancers in the US. Incidence rates increase with age, particularly after age 40, and are higher in men, particularly African American men. The etiology is unknown with no established lifestyle, occupational or environmental risk factors. Although several factors have been implicated as potentially etiologic, findings are inconsistent. We reviewed epidemiologic studies that evaluated lifestyle, dietary, occupational and environmental factors; immune function, family history and genetic factors; and the hypothesized precursor, monoclonal gammopathies of undetermined significance (MGUS). Because multiple myeloma is an uncommon disease, etiologic assessments can be difficult because of small numbers of cases in occupational cohort studies, and few subjects reporting exposure to specific agents in case-control studies. Elevated risks have been reported consistently among persons with a positive family history of LHC. A few studies have reported a relationship between obesity and multiple myeloma, and this may be a promising area of research. Factors underlying higher incidence rates of multiple myeloma in African Americans are not understood. The progression from MGUS to multiple myeloma has been reported in several studies; however, there are no established risk factors for MGUS. To improve our understanding of the causes of multiple myeloma, future research efforts should seek the causes of MGUS. More research is also needed on the genetic factors of multiple myeloma, given the strong familial clustering of the disease.

Tobacco and alcohol consumption and risk of lymphoma: Results of apopulation-based case-control study in Germany

Changing trends in lifestyle exposures are suggested to be contributing factors to the increasing incidence rates for lymphoma. We investigated the relationship between smoking and alcohol consumption and the risk of lymphoma among adult participants of a population-based case-control study recently conducted in Germany. In 710 case-control pairs, an increased risk of lymphoma was associated with a long duration of smoking (p for trend = 0.01 for men) and smoking of > 20 cigarettes per day(OR = 2.7; 95% CI = 1.4-5.2 for women). Elevated odds ratios were seen for most lymphoma subentities, albeit mostly without reaching statistical significance. A strong association was evident between smoking and multiple myeloma (OR = 2.4, 95% CI = 0.98-5.74 for men; OR = 2.9, 95% CI = 1.1-7.4 for women) and Hodgkin's lymphoma among men (OR = 3.6; 95% CI = 1.7-7.5). Alcohol consumption 10 years prior to the date of interview appeared to decrease the risk of lymphoma. Odds ratios for men who reported alcohol consumption were 53% lower (95% CI = 0.31-0.71) compared to men who drank very little or no alcohol. The same tendency was evident for women, although the association was less pronounced. The inverse relationship was also seen for low amounts of alcohol and did not appear to be restricted to specific types of beverages. Although biologic rationale for a protective effect of alcohol consumption may be given, a more in-depth analysis involving genetic markers is indicated to clarify if ethanol, other components in alcoholic beverages, or factors associated with moderate drinking reduce lymphoma risk among adults. In conclusion, this investigation suggests a positive association between tobacco smoking and lymphoma risk and finds decreased odds ratios among consumers of alcohol.

Tobacco smoking, alcohol drinking and non-Hodgkin's lymphoma: A European multicenter case-control study (Epilymph)

To study the role of tobacco smoking and alcohol drinking in the etiology of non-Hodgkin's lymphoma (NHL), we conducted a multicenter case-control study in Spain, France, Germany, Italy, Ireland and Czech Republic between 1998 and 2004, which included 1,742 cases of NHL and 2,465 controls matched on age, sex and recruitment area. Tobacco smoking was not associated with the risk of NHL overall or with risk of specific histological subtypes. Similarly, there was no association between alcohol drinking and the risk of NHL overall or across histological subtypes. However, a protective effect of alcohol drinking was observed among men (OR = 0.76, 95% CI = 0.62-0.93) and in non-Mediterranean countries (OR = 0.73, 95% CI = 0.61-0.86). There was no evidence of interaction between alcohol drinking and tobacco smoking in NHL etiology. The results of this large-scale European study did not support an association between tobacco and NHL and suggested a protective effect of alcohol on development of NHL for men and in non-Mediterranean countries.

Tobacco use and non-Hodgkin lymphoma: results from a population-based case-control study in the San Francisco Bay Area, California

OBJECTIVE

Investigate the association between tobacco use and non-Hodgkin lymphoma (NHL).

METHODS

Tobacco-use data were collected during in-person interviews in a population-based case-control study of NHL (N=1593 patients, N=2515 controls) conducted in the San Francisco Bay Area between 1988 and 1995. Odds ratios (ORs) for HIV-negative participants were obtained from adjusted unconditional logistic regression models stratified by sex.

RESULTS

NHL was not associated with overall tobacco use, intensity or duration of cigarette smoking in women or men. However, ORs were increased for NHL among men who used any non-cigarette tobacco alone (OR=1.7), non-cigarette tobacco and cigarettes (OR=1.4), multiple types of non-cigarette tobacco alone (OR=2.1) and smokeless tobacco alone (OR=4.0). In analyses stratified by sex and age, ORs for NHL associated with cigarette smoking in general were above unity among those aged > or =60 years. ORs for follicular lymphoma were increased in men who used cigarettes and other tobacco, cigars alone and smokeless tobacco alone. Diffuse large-cell lymphoma in men was associated with use of cigarettes and other tobacco, and multiple types of non-cigarette tobacco.

CONCLUSION

Our data do not support an association between overall tobacco use and all NHL in women or men. Further analyses are warranted in larger studies to evaluate non-cigarette tobacco use, tobacco-related biologic markers and genetic factors in the development of NHL.

Cigarette smoking and risk of non-Hodgkin's lymphoma--a population-based case-control study

BACKGROUND

Epidemiologic evidence of an association between tobacco smoking and non-Hodgkin's lymphoma has been conflicting. This may reflect that non-Hodgkin's lymphoma comprises several distinct disease entities with different etiologies, as some studies have indicated an association between smoking and follicular lymphoma.

OBJECTIVE

To investigate the association between cigarette smoking and non-Hodgkin's lymphoma risk, overall and by subtype.

METHODS

As part of a nationwide Danish-Swedish population-based case-control study, we interviewed 3,055 incident non-Hodgkin's lymphoma patients and 3,187 population controls. All lymphomas were uniformly classified according to the WHO classification. We used unconditional logistic regression to estimate adjusted odds ratios (OR) and 95% confidence intervals (95% CI) for the association between cigarette smoking and risk of non-Hodgkin's lymphoma.

RESULTS

Cigarette smoking was not associated with the risk of non-Hodgkin's lymphoma overall (OR, 0.97; 95% CI, 0.87-1.08) nor with the major subgroups such as diffuse large B-cell lymphoma (OR, 0.94; 95% CI, 0.79-1.10), chronic lymphocytic leukemia (OR, 0.86; 95% CI, 0.72-1.02), or follicular lymphoma (OR, 1.03; 95% CI, 0.85-1.24). Female smokers were at a marginally increased risk of follicular lymphoma (OR, 1.41; 95% CI, 1.04-1.92). Men who had ever smoked had a significantly increased risk of T-cell lymphoma (OR, 1.67; 95% CI, 1.11-2.51). No dose-response association with cigarette smoking could be established for any lymphoma subgroup.

CONCLUSION

We found little evidence of an association between cigarette smoking and non-Hodgkin's lymphoma risk overall. Although increased risks of follicular lymphoma in female smokers and of T-cell lymphoma in male smokers were suggested, no dose-response relationship was observed, leaving limited support for causality.

Smoking and non‐Hodgkin lymphoma: Case‐control study in Italy

Tobacco smoking is a well-documented risk factor for several cancers, but the role of cigarette smoking in the etiology of non-Hodgkin lymphoma (NHL) is inadequately understood. Hepatitis C virus (HCV) has been associated with NHL, but the interaction between HCV and smoking habits has not yet been studied. Between 1999 and 2002, we conducted a case-control study on the association of HCV, smoking habits and NHL in 2 areas of northern and southern Italy. Cases were 225 consecutive patients (median age, 59 years) with a new diagnosis of NHL that were admitted to reference and general hospitals. Controls were 504 patients (median age, 63 years) admitted to the same hospitals as cases, for a wide spectrum of acute, nonneoplastic, nonimmune-, nor tobacco-related conditions. Current, heavy smokers (> or = 20 cigarettes/day) had an odds ratio (OR) of NHL of 2.10 (95% confidence interval, CI: 1.07-4.12) compared to never smokers. The association between smoking and NHL was consistent across strata of sex and age. Compared to never smokers, current smokers of > or = 20 cigarettes/day had ORs of 1.14 (95% CI: 0.37-3.56) for B-cell-low-grade, 2.10 (95% CI: 0.94-4.67) for B-cell-intermediate and high-grade, and 25.84 (95% CI: 1.95-342.17) for T-cell NHL. The effect of tobacco smoking and HCV were independent on the relative risk, leading a 4-fold elevated risk in current smokers HCV positive subjects. Tobacco smoking and hepatitis C virus (HCV) have been associated to non-Hodgkin lymphoma (NHL), but the interaction between HCV and smoking habits has not yet been studied. Our study confirms that tobacco is related to NHL, and reports on the combined effect of tobacco smoking and HCV. Infection acted together according to a multiplicative model, leading to a 4-fold elevated risk in current smokers HCV positive subjects.

Cigarette Smoking and Risk of Non-Hodgkin Lymphoma: A Pooled Analysis from the International Lymphoma Epidemiology Consortium (InterLymph)

BACKGROUND

The International Lymphoma Epidemiology Consortium (InterLymph) provides an opportunity to analyze the relationship between cigarette smoking and non-Hodgkin lymphoma with sufficient statistical power to consider non-Hodgkin lymphoma subtype. The results from previous studies of this relationship have been inconsistent, likely due to the small sample sizes that arose from stratification by disease subtype. To clarify the role of cigarette smoking in the etiology of non-Hodgkin lymphoma, we conducted a pooled analysis of original patient data from nine case-control studies of non-Hodgkin lymphoma conducted in the United States, Europe, and Australia.

METHODS

Original data were obtained from each study and uniformly coded. Risk estimates from fixed-effects and two-stage random-effects models were compared to determine the impact of interstudy heterogeneity. Odds ratios (OR) and 95% confidence intervals (95% CI) were derived from unconditional logistic regression models, controlling for study center, age, sex, and race.

RESULTS

In our pooled study population of 6,594 cases and 8,892 controls, smoking was associated with slightly increased risk estimates (OR, 1.07; 95% CI, 1.00-1.15). Stratification by non-Hodgkin lymphoma subtype revealed that the most consistent association between cigarette smoking and non-Hodgkin lymphoma was observed among follicular lymphomas (n = 1452). Compared with nonsmokers, current smokers had a higher OR for follicular lymphoma (1.31; 95% CI, 1.12-1.52) than former smokers (1.06; 95% CI, 0.93-1.22). Current heavy smoking (> or = 36 pack-years) was associated with a 45% increased OR for follicular lymphoma (1.45; 95% CI, 1.15-1.82) compared with nonsmokers.

CONCLUSIONS

Cigarette smoking may increase the risk of developing follicular lymphoma but does not seem to affect risk of the other non-Hodgkin lymphoma subtypes we examined. Future research is needed to determine the biological mechanism responsible for our subtype-specific results.

Overview of smoking and all cancers

Tobacco consumption has been clearly implicated in the causation of many cancer types, with irrefutable evidence to support the association in multiple organ systems. Tobacco cessation leads to reduced cancer risk and improved survival of those under treatment for their already established cancers. As understanding of the mechanisms by which tobacco products cause cancer increases, clinicians may be able to identify those at highest risk for tobacco-related malignancies and allow for more focused interventions toward risk reduction among current tobacco users. This article reviews the carcinogens present in tobacco products, the mechanisms by which tobacco causes cancer, and the various tumor types causally related to tobacco use.

Non-Hodgkin's Lymphoma and Type of Tobacco Smoke

Background: In recent decades, the incidence of non-Hodgkin's lymphoma (NHL) has increased in all industrialized countries. Tobacco smoke contains several recognized or putative carcinogenic compounds that differ in concentration depending on which of the two main types, blond or black, is consumed. This investigation sought to evaluate the association between NHL and type of tobacco smoked (blond, black, or mixed), focusing on the Working Formulation (WF) subgroups. Methods: Reanalysis of Italian data from a recent multicenter population-based case-control study. The 1450 cases of NHL and 1779 healthy controls from 11 Italian areas with different demographic and productive characteristics were included in the study, corresponding to ∼7 million residents. Odds ratios (ORs) adjusted for age, gender, residence area, educational level, and type of interview were estimated by unconditional logistic regression model. Results: A statistically significant association [OR = 1.4, 95% confidence interval (CI) 1.1–1.7] was found for blond tobacco exposure and NHL risk. A dose-response relationship was limited to men younger than 52 years (χ2 for trend = 9.95, P &lt; 0.001). Subjects starting smoking at an early age showed a higher risk in men younger than 65 years, whereas no clear trend was evident for the other age and gender subgroups. The analysis by WF categories showed the highest risks for follicular lymphoma in blond (OR = 2.1, 95% CI 1.4–3.2) and mixed (OR = 1.8, 95% CI 1.1–3.0) tobacco smokers and for large cell within the other WF group (OR = 1.6, 95% CI 1.1–2.4) only for blond tobacco. Conclusion: Smoking blond tobacco could be a risk factor for NHL, especially follicular lymphoma.

Cigarette smoking and risk of non-Hodgkin lymphoma subtypes among women

Previous studies of the relationship between cigarette smoking and non-Hodgkin lymphoma (NHL) have yielded conflicting results, perhaps because most studies have evaluated the risk for all NHL subtypes combined. Data from a population-based case–control study conducted among women in Connecticut were used to evaluate the impact of cigarette smoking on the risk of NHL by histologic type, tumour grade, and immunologic type. A total of 601 histologically confirmed, incident cases of NHL and 718 population-based controls provided in-person interviews. A standardised, structured questionnaire was used to collect information on each subject's current smoking status, age at initiation, duration and intensity of smoking, and cumulative lifetime exposure to smoking. Our data suggest that cigarette smoking does not alter the risk of all NHL subtypes combined. However, increased risk of follicular lymphoma appears to be associated with increased intensity and duration of smoking, and cumulative lifetime exposure to smoking. Compared with nonsmokers, women with a cumulative lifetime exposure of 16–33 pack-years and 34 pack-years or greater experience 50% increased risk (OR=1.5, 95% CI 0.9–2.5) and 80% increased risk (OR=1.8, 95% CI 1.1–3.2), respectively, of follicular lymphoma (P for linear trend=0.05). Our study findings are consistent with several previous epidemiologic studies suggesting that cigarette smoking increases the risk of follicular lymphoma. This research highlights the importance of distinguishing between NHL subtypes in future research on the aetiology of NHL.

Tobacco use and cancer causation: association by tumour type

In the second part of our review we describe the association between tobacco use and risk of specific cancer types. There is evidence for an established association of tobacco use with cancer of the lung and larynx, head and neck, bladder, oesophagus, pancreas, stomach and kidney. In contrast, endometrial cancer is less common in women who smoke cigarettes. There are some data suggesting that tobacco use increases the risk for myeloid leukaemia, squamous cell sinonasal cancer, liver cancer, cervical cancer, colorectal cancer after an extended latency, childhood cancers and cancer of the gall bladder, adrenal gland and small intestine. Other forms of cancer, including breast, ovarian and prostate cancer, are unlikely to be linked to tobacco use.

Insights into the molecular pathogenesis of follicular lymphoma arising from analysis of geographic variation

Incidence rates of follicular lymphoma (FL) inexplicably vary markedly between Western and Asian countries. A hallmark of FL is the bcl-2 translocation, characterized by 1 of 2 common breakpoints known as major breakpoint region (MBR) and minor cluster region (mcr). We analyzed previously published data to compare rates of bcl-2 translocation in FL across geographic regions. Available data from the literature suggest that the incidence of bcl-2 in healthy persons in the absence of FL may be as high as 50% in Western and Asian populations. However, in FL our results show that the frequency of bcl-2 positivity was significantly higher for US than for Asian populations (P <.0001). This pattern persisted for MBR and mcr subgroups. We conclude that a significant gradient exists in the bcl-2 frequency between these FL populations. We therefore suggest that the relatively low incidence of FL in Asian populations is caused not by a lower frequency of bcl-2 rearrangements in healthy populations but by distinct molecular pathways developing in different geographic regions that nonetheless culminate in FL, which is morphologically similar but molecularly distinct. Studies demonstrating differences in clinical characteristics according to the presence or absence of bcl-2 rearrangements support this concept. Thus we hypothesize that FL may in fact be a heterogeneous malignancy encompassing entities with distinct molecular pathogenesis and potentially distinct clinical manifestations. If these findings were confirmed in prospective studies, it would imply that different etiologic or genetic factors might influence the development of FL across separate regions.

Alcohol, smoking, and dietary status and susceptibility to malignant lymphoma in Japan: results of a hospital-based case-control study at Aichi Cancer Center

Recent increase in the incidence of malignant lymphoma (ML) suggests possible involvement of lifestyle or environmental factors in its genesis. However, evidence for an effect of lifestyle factors, especially diet, on ML risk among Japanese is lacking. To explore the possibility that lifestyle factors exert an influence, we have conducted a hospital-based case-control study with 333 histologically confirmed ML cases and 55904 non-cancer controls who first visited Aichi Cancer Center Hospital between 1988 and 1997. Multiple logistic regression analysis showed regular alcohol consumption to be associated with reduced risk of ML, whereas no risk change was observed for smoking. Some other factors including intake of vegetables (carrots and pumpkin), pork and fish showed partial associations, but their significance needs further clarification. From the previous study on genetic background for ML [Matsuo et al., Blood, 97, 3205 - 3209 (2001)], genetic variation combined with limited environmental factors should be targeted in future studies.

Incidence of cancer among bookbinders, printers, photoengravers, and typesetters

OBJECTIVES

To to study the risk of cancer, particularly of lung cancer and bladder cancer, among workers in the printing industry according to different occupations.

METHODS

This is a population based retrospective cohort study. The cohort comprised 1332 men and 426 women employed in the printing industry in Iceland according to a published union registry. A computerised file of the cohort was record linked to the Cancer Registry by making use of personal identification numbers. Expected numbers of cases of cancer were calculated on the basis of number of person-years and specific incidences of cancer sites for men and women provided by the Cancer Registry.

RESULTS

Among the men (36 217.5 person-years at risk) there were 125 observed cancers versus 123.66 expected, standardised incidence ratio (SIR) 1.01, 95% confidence interval (95% CI) was 0.84 to 1.20. The SIR (95% CI) for liver cancer was 1.97 (0.55 to 5.20) and the SIR for non-Hodgkin's lymphoma was 2.26 (0.96 to 4.41). No excess risk for cancer was found among women (8631.0 person-years at risk). The SIR (95% CI) for liver cancer was 4.21 (0.47 to 15.20) and for non-Hodgkin's lymphoma it was 4.99 (1.61 to 11.63) among the typesetters. A survey on smoking habits among active and retired union members showed that they smoked less than a random sample of the general population.

CONCLUSION

The cancer site most often reported to show excess risk among printing industry workers has been the lung and the urinary bladder; however, this was not found in the present study. This may be explained by difference in smoking habits among union members compared with the general population. There is a high occurrence of non-Hodgkin's lymphoma, particularly among typesetters, which warrants further studies.

Critical review of epidemiological studies of the association between smoking and non-Hodgkin's lymphoma

Smoking has been suggested to increase the risk of non-Hodgkin's lymphoma (NHL) but the results of epidemiological studies have been inconsistent. The aim of this work was to assess whether the findings of individual studies might have arisen by chance, bias or confounding and whether any associations found between smoking and NHL represent cause-and-effect. Reports of the association between smoking and NHL were identified from Medline. Confidence intervals on relative risks and odds ratios, use of multiple comparisons, and information on source, direction, actual existence and size of potential biases and confounding and features of any associations were abstracted. Four out of five cohort studies found no association between current smoking and NHL but three may have been biased against doing so. One found an association with follicular lymphoma but without a convincing exposure-risk gradient. The fifth found a strong association and an exposure-response gradient with ever smoking but excluded living cases from the end-point. Only one study found an association with past smoking which lacked features of causality. Eight out of 14 case-control studies found no association between current and/or past smoking and NHL but five may have been biased against doing so. Of six positive studies, three involved multiple comparisons, the association of one became non-significant after eliminating bias, four did not explore features of causality and one found an association only in heavy smokers, particularly under 45 years old. There are no grounds to reject the null hypothesis but associations should continue to be sought particularly in subgroups of smokers and with NHL subtypes.

Epidemiology of lymphomas

Non-Hodgkin lymphoma (NHL) is the fifth most common cancer in the US, with about 55,000 new cases estimated for the year 2000. According to the new Surveillance, Epidemiology, and End Results (SEER) data from 1973 to 1997, the age-adjusted incidence rates rose by about 80%, with an annual percentage increase of nearly 3%, which is faster than for the majority of cancers. The increasing incidence of NHL is largely unexplained. AIDS-related NHL accounts for some but not all of the increase. The American Cancer Society predicts about 7,400 new cases of Hodgkin Disease (HD) in the year 2000 in the US. The incidence of HD is consistently lower than that of NHL, and has decreased about 16% since the 1970s. Only a small portion of the decrease in HD incidence can be explained by misdiagnosis of HD as NHL. Further research is needed on the cofactors that predispose AIDS cases to lymphoma, as well as other possible causes of NHL such as immunosuppression, genetics, viruses, medical conditions, pesticides, solvents, hair dyes, and diet. Further evaluation of the role of viruses, occupational exposures, and genetics in the etiology of HD should prove valuable.

Cancer surveillance series: non-Hodgkin's lymphoma incidence by histologic subtype in the United States from 1978 through 1995

BACKGROUND

Clinical investigations have shown prognostic heterogeneity within the non-Hodgkin's lymphomas (NHLs) according to histology, but few descriptive studies have considered NHLs by subgroup. Our purpose is to assess the demographic patterns and any notable increases in population-based rates of different histologic subgroups of NHL.

METHODS

Using data collected by the Surveillance, Epidemiology, and End Results Program of the National Cancer Institute, we calculated incidence rates for the major clinicopathologic categories of NHL by age, race, sex, geographic area, and time period.

RESULTS

Among the 60 057 NHL cases diagnosed during the period from 1978 through 1995, total incidence (per 100 000 person-years) was 17.1 and 11.5 among white males and females, respectively, and 12.6 and 7.4 among black males and females, respectively. However, rates for follicular NHLs were two to three times greater among whites than among blacks, with little sex variation. Blacks demonstrated much higher incidence than whites for peripheral T-cell NHL, with the incidence rates higher in males than in females. For other NHL subgroups, the incidence rates for persons less than 60 years of age were generally higher among males than among females, with little racial difference; at older ages, the rates were higher among whites than among blacks, with little sex difference. High-grade NHL was the most rapidly rising subtype, particularly among males. Follicular NHL increased more rapidly in black males than in the other three race/sex groups. Overall, the broad categories of small lymphocytic, follicular, diffuse, high-grade, and peripheral T-cell NHL emerged as distinct entities with specific age, sex, racial, temporal, and geographic variations in rates.

CONCLUSIONS

Findings from our large, population-based study reveal differing demographic patterns and incidence trends according to histologic group. Future descriptive and analytic investigations should evaluate NHL risks according to subtype, as defined by histology and new classification criteria.

Smoking and risk of non-Hodgkin lymphoma subtypes in a cohort of older women

Although non-Hodgkin lymphoma (NHL) has not been considered to be a smoking-related malignancy, recent investigations suggest otherwise. We evaluated this association in a cohort of 37,336 women, aged 55-69 years, who reported in a mailed questionnaire in 1986 information regarding smoking history as well as demographic, medical history and dietary factors. Cancer and mortality experience through 1996 was determined by linkage to the Iowa Cancer Registry and other databases; there were 200 incident cases of NHL during the 380,231 total person-years of follow-up. Compared to never smokers, former (age-adjusted RR = 1.0; 95% CI 0.8-1.5) and current smokers (age-adjusted RR = 1.0; 95% CI 0.7-1.5) were not at elevated risk of NHL, and there was no trend with pack-years smoked (Ptrend = 0.3). Multivariate adjustment for other NHL risk factors did not alter these findings. Age-adjusted analysis by NHL subtype revealed a suggestive positive association of smoking with follicular NHL [(RRformer = 1.3; 95% CI 0.6-2.8), (RRcurrent = 1.8; 95% CI 0.8-3.8)], which strengthened after multivariate adjustment [(RRformer = 1.6; 95% CI 0.7-3.4), (RRcurrent = 2.3; 95% CI 1.0-5.0)]; there was no association for diffuse or small cleaved-cell NHL. Our study findings, which are consistent with other recent investigations, suggest that smoking may be associated with an increased risk of follicular NHL.

Occupational, environmental, and life-style factors associated with the risk of hematolymphopoietic malignancies in women

BACKGROUND

The etiology of lymphomas, leukemias, and multiple myeloma is still largely unknown. The known risk factors (ionizing radiation, solvent exposure, pesticide exposure, immunosuppression) explain only a small proportion of the cases that occur.

METHODS

We conducted a multicenter population-based case-control study on hematolymphopoietic malignancies in Italy and interviewed 2,011 women (1,183 cases and 828 controls).

RESULTS

There was a suggestion of a positive association between smoking and the risk of non-Hodgkin's lymphoma + chronic lymphocytic leukemia. A slight increased risk of leukemias was observed among women using permanent hair dye. Housewives were at increased risk for leukemia and multiple myeloma. The risk of non-Hodgkin's lymphomas + chronic lymphocytic leukemia, leukemias, multiple myeloma, and Hodgkin's disease increased among women employed as hairdressers and textile workers. Teachers were at increased risk for non-Hodgkin's lymphomas + chronic lymphocytic leukemia, leukemias, and Hodgkin's disease.

CONCLUSIONS

These results confirm previous associations and may provide additional clues to some determinants of hematolymphopoietic malignancies in women.

Second primary cancers in patients with lung carcinoma

BACKGROUND

There are only limited population-based data available regarding the risk of developing a second cancer after a diagnosis of lung carcinoma.

METHODS

Data collected from the Cancer Registry of the Swiss Canton of Vaud (comprised of approximately 600,000 inhabitants) were used to estimate the incidence of a second metachronous primary cancer following a diagnosis of lung carcinoma. Between 1974 and 1996, 5794 cases of lung carcinoma (occurring in 4728 males and 1066 females) were followed actively until the end of 1996.

RESULTS

One hundred seventy-five second primary neoplasms were registered (occurring in 146 males and 29 females). Significant excess rates were observed for all cancer sites (standardized incidence ratio [SIR] = 1.2), cancers of the oral cavity and pharynx (SIR = 2.7), and lung (SIR = 1.7). SIRs also were above unity for cancers of the esophagus (SIR = 1.8), pancreas (SIR = 1.5), bladder (SIR = 1.8), kidney (SIR = 2.3), and the female breast (SIR = 2.0). Excess rates for all cancer sites together and tobacco-related neoplasms were systematically higher at a younger age (< 60 years). The overall cumulative risk of lung cancer was 1.8% at 5 years and 4.7% at 10 years and was 5% and 11%, respectively, for any tobacco-related tumor. The estimates were consistent for squamous cell carcinoma and adenocarcinoma of the lung.

CONCLUSIONS

There were substantial excesses of second lung carcinomas as well as other major tobacco-related neoplasms, but not of colorectal carcinoma, prostate carcinoma, or lymphoid neoplasms after the diagnosis of a primary lung carcinoma. This study emphasizes the importance of smoking cessation even after a diagnosis of lung carcinoma.

Intermediate and high grade non Hodgkin's lymphoma in the elderly

Many malignant tumors develop in the later years of life. One of malignancies that frequently occurs in older patients is non Hodgkin's lymphoma (NHL) with a median age at diagnosis over 60 years. The overall incidence of NHL has increased over the past decade and is expected to continue to rise in developed countries. So NHL will be diagnosed more in the future. In this review we discuss epidemiology, etiology, possible differences in tumor characteristics compared with younger NHL patients, treatment and treatment results in elderly NHL patients.

Occupational exposures, animal exposure and smoking as risk factors for hairy cell leukaemia evaluated in a case-control study

To evaluate occupational exposures as risk factors for hairy cell leukaemia (HCL), a population-based case-control study on 121 male HCL patients and 484 controls matched for age and sex was conducted. Elevated odds ratio (OR) was found for exposure to farm animals in general: OR 2.0, 95% confidence interval (CI) 1.2-3.2. The ORs were elevated for exposure to cattle, horse, hog, poultry and sheep. Exposure to herbicides (OR 2.9, CI 1.4-5.9), insecticides (OR 2.0, CI 1.1-3.5), fungicides (OR 3.8, CI 1.4-9.9) and impregnating agents (OR 2.4, CI 1.3-4.6) also showed increased risk. Certain findings suggested that recall bias may have affected the results for farm animals, herbicides and insecticides. Exposure to organic solvents yielded elevated risk (OR 1.5, CI 0.99-2.3), as did exposure to exhaust fumes (OR 2.1, CI 1.3-3.3). In an additional multivariate model, the ORs remained elevated for all these exposures with the exception of insecticides. We found a reduced risk for smokers with OR 0.6 (CI 0.4-1.1) because of an effect among non-farmers.

Tobacco, alcohol, diet and risk of non-Hodgkin's lymphoma: a case-control study in Uruguay

To test whether high meat intake is associated with the development of non-Hodgkin lymphoma (NHL) in the Uruguayan population, a case-control study was performed at the Instituto Nacional de Oncologia, Montevideo, Uruguay. After controlling for age, sex, residence, education, urban/rural status and the habit of drinking the beverage 'mate', red meat intake was associated with an increased risk of NHL of 2.5. This finding was similar in both sexes separately. Odds ratios (OR) for the highest tertile of barbecued meat was 1.7 among men, whereas salted meat was associated with an increased risk of NHL (OR 4.9, 95% CI 1.4-17.7). The effect of processed and salted meat among women was of much less magnitude and the OR's were non-significant. Also, cumulative exposure to 'mate' drinking displayed an OR of 2.4 (95% CI 1.0-5.6). Smokers of black tobacco and hand-rolled cigarettes were associated with an increased risk of 3.5 (95% 1.1-10.9), whereas beer drinkers showed an increased OR of 5.5 (95% 1.1-26.7) in men. It could be concluded that red or salted meat intake, smoking of black tobacco, and beer and 'mate' drinking are risk factors for NHL in the Uruguayan population.

Lymphohaematopoietic malignancies and quantitative estimates of exposure to benzene in Canadian petroleum distribution workers

OBJECTIVE

To evaluate the relation between mortality from lymphohaematopoietic cancer and long term, low level exposures to benzene among male petroleum distribution workers.

METHODS

This nested case control study identified all fatal cases of lymphohaematopoietic cancer among a previously studied cohort. Of the 29 cases, 14 had leukaemia, seven multiple myeloma, and eight non-Hodgkin's lymphoma. A four to one matching ratio was used to select a stratified sample of controls from the same cohort, controlling for year of birth and time at risk. Industrial hygienists estimated workplace exposures for benzene and total hydrocarbons, without knowledge of case or control status, for combinations of job, location, and era represented in all work histories. Average daily benzene concentrations ranged from 0.01 to 6.2 parts per million (ppm) for all jobs. Company medical records were used to abstract information on other potential confounders such as cigarette smoking, although the data were incomplete. Odds ratios (ORs) were calculated with conditional logistic regression techniques for several exposure variables.

RESULTS

Risks of leukaemia, non-Hodgkin's lymphoma, and multiple myeloma were not associated with increasing cumulative exposure to benzene or total hydrocarbons. For leukaemia, the logistic regression model predicted an OR of 1.002 (P < 0.77) for each ppm-y of exposure to benzene. Duration of exposure to benzene was more closely associated with risk of leukaemia than other exposure variables. It was not possible to completely control for other risk factors, although there was suggestive evidence that smoking and a family history of cancer may have played a part in the risk of leukaemia.

CONCLUSION

This study did not show a relation between lymphohaematopoietic cancer and long term, low level exposures to benzene. The power of the study to detect low-such as twofold-risks was limited. Thus, further study on exposures to benzene in this concentration range are warranted.

Genotypic selection of mitochondrial and oncogenic mutations in human tissue suggests mechanisms of age-related pathophysiology

The invention of the polymerase chain reaction (PCR) has facilitated the development of a new class of assays to quantify human somatic mutations in vivo, based on genotypic selection of mutants at the DNA level rather than phenotypic selection of mutants at the cell level. Use of these assays has provided new perspectives on the timing, location and distribution of somatic mutagenesis in mitochondrial genes and in oncogenes of the aging human body. This descriptive information has led to the inference and development of new models for age-related pathophysiology and oncogenesis. Mutations of mitochondrial genes rise rapidly with age to frequencies a thousand fold higher than those of nuclear genes. Genotypic selection analysis has revealed that mitochondrial mutations accumulate predominantly in non-mitotic cells whose age-dependent loss is associated with pathology. Random mitochondrial mutation is most likely to inactive Complex I, a deficiency of which induces mitochondrial superoxide formation and cell death. Genotypic selection of oncogenic mutations at the BCL2 and p53 loci has revealed that the cell specificity of oncogenic mutations in persons without cancer correlates well with sites of tumor origin, indicating that cells bearing such mutations are the likely precursors of future tumors. Quantitative variation in human BCL2 mutation frequency is extensive, and BCL2 mutation frequency rises with age, concordant with increased risk for lymphoma. The clonality and persistence of BCL2 mutations suggests two specific testable mechanisms of lymphomagenesis. BCL2 mutation frequency rises in persons exposed to cigarette smoke, and more p53 mutations occur in skin exposed to sunlight than in unexposed skin. Thus, in addition to their likely relevance to future cancer risk, the dose-response relationship between exposure and oncogenic mutations indicates promise for their future use as in vivo biodosimeters of human exposure to carcinogens.

The causes and prevention of cancer

Epidemiological evidence indicates that avoidance of smoking, increased consumption of fruits and vegetables, and control of infections will have a major effect on reducing rates of cancer. Other factors include avoidance of intense sun exposure, increases in physical activity, and reduction of alcohol consumption and possibly red meat. A substantial reduction in breast cancer is likely to require modification of sex hormone levels, and development of practical methods for doing so is a high research priority. Resolution of the potential protective roles of specific antioxidants and other constituents of fruits and vegetables deserves major attention. Mechanistic studies of carcinogenesis indicate an important role of endogenous oxidative damage to DNA that is balanced by elaborate defense and repair processes. Also key is the rate of cell division, which is influenced by hormones, growth, cytotoxicity, and inflammation, as this determines the probability of converting DNA lesions to mutations. These mechanisms may underlie many epidemiologic observations.

Analysis of cancer risk related to longitudinal information on smoking habits

Radiation Effects Research Foundation (RERF) has followed the RERF Life Span Study (LSS) cohort consisting of atomic bomb survivors and unexposed subjects for more than 40 years. The information on their lifestyles, including smoking habits, has been collected in the past 25 years through two mail surveys of the entire LSS cohort and three interview surveys of a subcohort for the biennial medical examination program. In the present study an attempt was made to consolidate the information of smoking habits obtained from the five serial surveys, and then a risk analysis was conducted to evaluate the effect of updating the smoking information on the smoking-related risk estimates for lung cancer. The estimates of smoking-related risk became larger and estimates of dose-response became sharper by updating smoking information using all of the data obtained from the five serial surveys. Analyses were also conducted for cancer sites other than lung. The differences in risk estimates between the two approaches were not as evident for the other cancer sites as for lung.

Epidemiology of non-Hodgkin's lymphoma: recent findings regarding an emerging epidemic

Between 1973 and 1989, the incidence of non-Hodgkin's lymphoma (NHL) increased by nearly 60% in the United States, one of the largest increases of any cancer. In 1993, approximately 43,000 new cases of NHL will be diagnosed and over 20,000 deaths due to NHL will occur. The annual incidence rate of NHL per 100,000 persons in the US has risen from 5.9 in 1950 to 13.7 in 1989. This increase has occurred in both males and females, blacks and whites, and in all age groups except the very young. The largest increase has occurred in the elderly, and rates have increased more rapidly in rural areas. Most of the increase cannot be attributed to acquired immunodeficiency syndrome. Similar findings have been reported from other developed countries. Epidemiologic studies indicate that environmental factors may play an important role in the etiology of NHL. In this paper, current knowledge concerning the epidemiology of NHL is summarized, with special emphasis on environmental factors of possible etiologic importance, such as drugs, pesticides, solvents and other chemicals, dusts and particles, hair dyes, smoking, Helicobacter pylori infection, and diet. Many different environmental factors of low risk acting on large segments of the population could account for much of the increase in NHL.