Classic Hodgkin lymphoma in young people

Classic Hodgkin lymphoma (CHL) is a unique form of lymphoid cancer featuring a heterogeneous tumor microenvironment and a relative paucity of malignant Hodgkin and Reed-Sternberg (HRS) cells with characteristic phenotype. Younger individuals (children, adolescents and young adults) are affected as often as the elderly, producing a peculiar bimodal age-incidence profile that has generated immense interest in this disease and its origins. Decades of epidemiological investigations have documented the populations most susceptible and identified multiple risk factors that can be broadly categorized as either biological or environmental in nature. Most risk factors result in overt immunodeficiency or confer more subtle alterations to baseline health, physiology or immune function. Epstein Barr virus, however, is both a risk factor and well-established driver of lymphomagenesis in a significant subset of cases. Epigenetic changes, along with the accumulation of somatic driver mutations and cytogenetic abnormalities are required for the malignant transformation of germinal center-experienced HRS cell precursors. Chromosomal instability and the influence of endogenous mutational processes are critical in this regard, by impacting genes involved in key signaling pathways that promote the survival and proliferation of HRS cells and their escape from immune destruction. Here we review the principal features, known risk factors and lymphomagenic mechanisms relevant to newly diagnosed CHL, with an emphasis on those most applicable to young people.

Lymphoblastic lymphoma in two young siblings (coincidence or genetics?): two case reports

BACKGROUND

Non-Hodgkin lymphoma is the fourth most common malignancy in children, and it is not considered to be a hereditary disorder. However, it could affect members from the same family.

CASE PRESENTATION

We are presenting two cases of Caucasian female siblings who were diagnosed with mediastinal lymphoblastic lymphoma in the same year. The two young females were presented to the emergency department with respiratory symptoms. After doing radiological investigations and biopsies, they were diagnosed with lymphoblastic lymphoma. The elder sister died before confirming the diagnosis, and the other is on chemotherapy now, with good treatment outcomes.

CONCLUSIONS

This case emphasizes the crucial role of precursor genetics in lymphoblastic lymphomas and suggests a strong relation between these genetics and age at symptom presentation. This is the first report of non-Hodgkin lymphoma in a pair of siblings in the pediatric population.

Genetic predisposition to lymphomas: Overview of rare syndromes and inherited familial variants

Approximately 10 % of malignancies occur in carriers of germline mutations predisposing to cancer. A high risk of developing lymphomas has been noted in many primary immunodeficiencies, including DNA repair disorders. Moreover, implementation of next-generation sequencing has recently enabled to uncover rare genetic variants predisposing patients to lymphoid neoplasms. Some patients harboring inherited predisposition to lymphomas require dedicated clinical management, which will contribute to effective cancer treatment and to the prevention of potential severe toxicities and secondary malignancies. In line with that, our review summarizes the natural history of lymphoid tumors developing on different germline genetic backgrounds and discusses the progress that has been made toward successfully treating these malignancies.

Familial aggregation of early-onset haematological malignancies

Population-based studies on familial aggregation of haematological malignancies (HM) have rarely focused specifically on early-onset HMs. We estimated standardized incidence ratios (SIR) and cumulative risks of relatives with Hodgkin lymphoma (HL), non-Hodgkin lymphomas (NHL), acute lymphoblastic leukaemia/lymphoma (ALL/LBL) and acute myeloid leukaemia (AML) when index persons and relatives were diagnosed with early-onset HM. A total of 8791 patients aged ≤40 years and diagnosed with primary HM in Finland from 1970 to 2012 were identified from the Finnish Cancer Registry and their 75 774 family members were retrieved from the population registry. SIRs for concordant HMs were elevated among first-degree relatives in all of the most common HMs of children and adolescents and young adults (AYA). The risk was highest among siblings with HL (SIR 9·09, 95% confidence interval 5·55-14·04) and AML (8·29, 1·00-29·96). HL also had the highest cumulative risk for siblings at ≤40 years of age (0·92% vs. 0·11% in the population). In conclusion, significantly elevated SIRs indicate a role of shared aetiological factors in some families, which should be noted in the clinical setting when caring for patients with early-onset HMs.

Combined linkage and association analysis of classical Hodgkin lymphoma

The heritability of classical Hodgkin lymphoma (cHL) has yet to be fully deciphered. We report a family with five members diagnosed with nodular sclerosis cHL. Genetic analysis of the family provided evidence of linkage at chromosomes 2q35-37, 3p14-22 and 21q22, with logarithm of odds score >2. We excluded the possibility of common genetic variation influencing cHL risk at regions of linkage, by analysing GWAS data from 2,201 cHL cases and 12,460 controls. Whole exome sequencing of affected family members identified the shared missense mutations p.(Arg76Gln) in FAM107A and p.(Thr220Ala) in SLC26A6 at 3p21 as being predicted to impact on protein function. FAM107A expression was shown to be low or absent in lymphoblastoid cell lines and SLC26A6 expression lower in lymphoblastoid cell lines derived from p.(Thr220Ala) mutation carriers. Expression of FAM107A and SLC26A6 was low or absent in Hodgkin Reed-Sternberg (HRS) cell lines and in HRS cells in Hodgkin lymphoma tissue. No sequence variants were detected in KLHDC8B, a gene previously suggested as a cause of familial cHL linked to 3p21. Our findings provide evidence for candidate gene susceptibility to familial cHL.

Nonrandom occurrence of lymphoid cancer types in 140 families

We studied 140 families with two or more lymphoid cancers, including non-Hodgkin lymphoma (NHL), Hodgkin lymphoma (HL), chronic lymphocytic leukemia (CLL), and multiple myeloma (MM), for deviation from the population age of onset and lymphoid cancer co-occurrence patterns. Median familial NHL, HL, CLL and MM ages of onset are substantially earlier than comparable population data. NHL, HL and CLL (but not MM) also show earlier age of onset in later generations, known as anticipation. The co-occurrence of lymphoid cancers is significantly different from that expected based on population frequencies (p < .0001), and the pattern differs more in families with more affected members (p < .0001), suggesting specific lymphoid cancer combinations have a shared genetic basis. These families provide evidence for inherited factors that increase the risk of multiple lymphoid cancers. This study was approved by the BC Cancer Agency - University of British Columbia Clinical Research Ethics Board.

Ethnic variation in medical and lifestyle risk factors for B cell non-Hodgkin lymphoma: A case-control study among Israelis and Palestinians

Background

Risk factors for B-cell non-Hodgkin lymphoma (B-NHL) have not been assessed among Palestinian Arabs (PA) and Israeli Jews (IJ).

Methods

In a case-control study we investigated self-reported medical and lifestyle exposures, reporting odds ratios (ORs) and 95% confidence intervals [CIs], by ethnicity, for overall B-NHL and subtypes.

Results

We recruited 823 cases and 808 healthy controls. Among 307 PA/516 IJ B-NHL cases (mean age at diagnosis = 51 [±17] versus 60 [±15] years, respectively) subtype distributions differed, with diffuse large B-cell lymphoma (DLBCL) being prominent among PA (71%) compared to IJ (41%); follicular lymphoma (FL), was observed in 14% versus 28%, and marginal zone lymphoma, in 2% versus 14%, respectively. Overall B-NHL in both populations was associated with recreational sun exposure OR = 1.43 [CI:1.07–1.91], black hair-dye use OR = 1.70 [CI:1.00–2.87], hospitalization for infection OR = 1.68 [CI:1.34–2.11], and first-degree relative with hematopoietic cancer, OR = 1.69 [CI:1.16–2.48]. An inverse association was noted with alcohol use, OR = 0.46 [CI:0.34–0.62]. Subtype-specific exposures included smoking (FL, OR = 1.46 [CI:1.01–2.11]) and >monthly indoor pesticide use (DLBCL, OR = 2.01 [CI:1.35–3.00]). Associations observed for overall B-NHL in PA only included: gardening OR = 1.93 [CI:1.39–2.70]; history of herpes, mononucleosis, rubella, blood transfusion (OR>2.5, P<0.01 for all); while for IJ risk factors included growing fruits and vegetables, OR = 1.87 [CI:1.11–3.15]; and self-reported autoimmune diseases, OR = 1.99 [CI:1.34–2.95].

Conclusions

In these geographically proximate populations we found some unique risk factors for B-NHL. Heterogeneity in the observed associations by ethnicity could reflect differences in lifestyle, medical systems, and reporting patterns, while variations by histology infer specific etiologic factors for lymphoma subtypes.

Familial predisposition and genetic risk factors for lymphoma

Our understanding of familial predisposition to lymphoma (collectively defined as non-Hodgkin lymphoma [NHL], Hodgkin lymphoma [HL], and chronic lymphocytic leukemia [CLL]) outside of rare hereditary syndromes has progressed rapidly during the last decade. First-degree relatives of NHL, HL, and CLL patients have an ∼1.7-fold, 3.1-fold, and 8.5-fold elevated risk of developing NHL, HL, and CLL, respectively. These familial risks are elevated for multiple lymphoma subtypes and do not appear to be confounded by nongenetic risk factors, suggesting at least some shared genetic etiology across the lymphoma subtypes. However, a family history of a specific subtype is most strongly associated with risk for that subtype, supporting subtype-specific genetic factors. Although candidate gene studies have had limited success in identifying susceptibility loci, genome-wide association studies (GWAS) have successfully identified 67 single nucleotide polymorphisms from 41 loci, predominately associated with specific subtypes. In general, these GWAS-discovered loci are common (minor allele frequency >5%), have small effect sizes (odds ratios, 0.60-2.0), and are of largely unknown function. The relatively low incidence of lymphoma, modest familial risk, and the lack of a screening test and associated intervention, all argue against active clinical surveillance for lymphoma in affected families at this time.

Ulcerative Colitis Diagnosed in a Patient after Primary Rectal Marginal Zone B-Cell Lymphoma of Mucosa-Associated Lymphoid Tissue (MALT) Treated

A 39-year-old woman presented with loose stool and rectal bleeding for 1 year. A colonoscopy was performed and revealed proctitis. Rectal biopsy revealed a diagnosis of rectal marginal B-cell lymphoma of mucosa-associated lymphoid tissue (MALT). She was treated with a course of chemotherapy rituximab. However, her symptoms persisted and a repeat colonoscopy showed features consistent with ulcerative colitis. She received topical mesalazine and her symptoms resolved. Another repeat colonoscopy showed evidence of inactive chronic colitis only. This is a rare report of ulcerative colitis being diagnosed after rectal MALT was treated. It is possible that she might have long-standing ulcerative colitis that was undiagnosed, with the rectal MALT lymphoma masking the features of ulcerative colitis. A few treatment modalities are available, and the prognosis in general is good.

Epidemiology and etiology of non-hodgkin lymphoma

Non-Hodgkin lymphoma (NHL) consists of many histologically and biologically distinct lymphoid malignancies with poorly understood, but possibly distinct, etiologies. The patterns of incidence and time trend vary not only by age, sex, and race/ethnicity in the USA, but also show significant geographic differences, suggesting the potential role of infectious agents, environmental factors, and lifestyle factors in addition to host genetic status in the development of NHL. Important pathogenetic mechanisms include immune modulation and chronic antigen stimulation. Epidemiologic studies in the past two decades have provided intriguing new insights on the possible causes of lymphoma and support the idea that there is some mechanistic commonality of lymphomagenesis, but significant etiologic heterogeneity clearly exists. This review presents a summary of the current understanding of the descriptive epidemiology and etiology of NHL and suggests areas of focus for future epidemiologic research.

Lymphoma and other lymphoproliferative disorders in inflammatory bowel disease: a review

The lymphoproliferative disorders (LDs) are a heterogeneous group of at least 70 conditions that result from the clonal proliferation of B, T, and NK cells. Inflammatory bowel disease (IBD)-associated lymphomas are typically B-cell LD, while T-cell or Hodgkin's lymphomas are rare. In IBD patients not on immunosuppression, the risk of LD seems to be similar or slightly higher than the background population risk. Thiopurine therapy is associated with an increased risk: the relative risk is increased four- to sixfold and the absolute risk varies between 1 in 4000-5000 for those aged 20-29 to 1 in 300-400 in those over 70. It is difficult to quantify the risk of anti- tumor necrosis factor (TNF) therapy alone; however, it appears to be less than for thiopurines alone. There is particular concern regarding the development of post-transplant-like LD in those with latent epstein-barr virus (EBV) infection exposed to immunosuppressives, the occurrence of hepatosplenic T cell lymphoma in patients treated with combination anti-TNF and thiopurine therapy, and the development of hemophagocytic lymphohistiocytosis in those who acquire a primary EBV or other infections while on immunosuppressive medication. There are currently no guidelines for monitoring EBV (or other virus) status in patients on immunosuppression, although it could be used to monitor those who have a prior history of lymphoma and are about to start a thiopurine or anti-TNF agent. In discussing the risks of lymphoproliferative disorders associated with agents used for the treatment of IBD, patients can often be reassured that the benefits of such therapy still outweigh the small, but real, risks.

Running in the family: MALT lymphoma and autoimmune disease in mother and daughter

Gastric B-cell lymphoma of the mucosa associated lymphoid tissue (MALT) lymphoma is one of the most common forms of extranodal lymphoma. In addition to infection with Helicobacter pylori (H. pylori), the presence of an underlying autoimmune disease has also been associated with MALT lymphoma development. To date, no familial predisposition for MALT lymphomas has been reported as opposed to other types of lymphoma. A 65-year-old woman was admitted at our institution in 1998 with a diagnosis of H. pylori positive gastric MALT lymphoma and the presence of chronic autoimmune thyroiditis was established on further work-up. H. pylori eradication did not result in regression of the lymphoma and RT-PCR showed the presence of the t(11;18)(q21;q21) translocation. About 1.5 years after H. pylori eradication, chemotherapy with cladribine resulted in complete remission. Due to lymphoma recurrence 13 mo later, radiotherapy to the stomach (46 Gy) resulted in minimal residual disease without further progression. The patient developed a second malignancy (Epstein-Bar virus-associated anaplastic large cell lymphoma in the mediastinum) in 2004 which initially responded to two courses of chemotherapy, but she refused further therapy and died of progressive lymphoma in 2006. In 2008, her 55 years old daughter with a long standing Sjögren’s syndrome was diagnosed with MALT lymphoma of the right parotid, but no evidence of gastric involvement or H. pylori infection was found. Currently, she is alive without therapy and undergoing regular check-ups. To our knowledge, this is the first report of MALT lymphoma in a first-degree relative of a patient with gastric MALT lymphoma in the context of two autoimmune diseases without a clearly established familial background.

Population-based proband-oriented pedigree information system: application to hypertension with population-based screening data (KCIS No. 25)

OBJECTIVE

To develop a population-based proband-oriented pedigree information system that can be easily applied to various diseases in genetic epidemiological studies, making allowance for the capture of theoretical family relationships. DESIGNS AND MEASUREMENTS: A population-based proband-oriented pedigree information system with ties of consanguinity based on both population-based household registry data and Keelung Community Integrated Screening data was proposed to build a comprehensive extended family pedigree structure to accommodate a series of genetic studies on different diseases. We also developed an algorithm to efficiently assess how well theoretical family relationships affecting the occurrence of diseases across three generations with respect to the relative relationship score, a quantitative indicator of genetic influence, were captured.

RESULTS

We applied this population-based proband-oriented pedigree information system to estimate the rate of hypertension with various relative relationships given the selection of probands. The degree of capturing complete familial relationships was assessed for three generations. The risk for early onset of hypertension was proportional to the proband-oriented relative relationship score with 2% increased risk and 1% correction for incomplete capture.

CONCLUSIONS

The population-based proband-oriented pedigree information system is powerful and can support various genetic descriptive and analytic epidemiological studies.

Survival patterns in patients with Hodgkin's lymphoma with a pre-existing hospital discharge diagnosis of autoimmune disease

PURPOSE

Autoimmune diseases (AIs) are associated with elevated risk for Hodgkin's lymphoma (HL); however, information on the interplay of AIs and HL on survival is sparse.

PATIENTS AND METHODS

We evaluated survival patterns for 7,414 patients with HL in relation to a pre-existing hospital discharge diagnosis of an AI. We also assessed survival patterns in relation to a prior AI diagnosis among 29,240 population-based matched controls.

RESULTS

Among female patients with HL with (v those without) a pre-existing AI, the 5-year and 10-year overall survival was 46.0% (63.3%) and 41.0% (51.9%); for males, the corresponding numbers were 48.5% (59.2%) and 43.6% (51.5%), respectively (P < .001). Among female controls with (v those without) a pre-existing AI, the 5-year and 10-year overall survival was 79.1% (90.2%) and 67.2% (83.3%); for males, the corresponding numbers were 82.5% (90.3%) and 68.6% (81.6%), respectively (P < .001). Female patients with HL with (v those without) a pre-existing AI had a 1.8-fold (range, 1.3- to 2.4-fold) increased relative risk of dying at 5 years of follow-up; for males, the corresponding excess relative risk of dying was 1.7-fold (range, 1.3- to 2.2-fold).

CONCLUSION

Patients with HL have an overall excellent outcome from treatment but also pose some of the most complex challenges of cancer survivorship due to many late effects (eg, second malignancies, thyroid disease, cardiovascular disease, and altered reproductive and sexual function). Our finding that patients with HL with a hospital discharge diagnosis of an AI have a substantially higher risk of dying, emphasizes that underlying chronic diseases, such as AIs, should be high of the list of survivorship concerns for clinicians that treat HL.

Polymorphisms and haplotypes in TLR9 and MYD88 are associated with the development of Hodgkin's lymphoma: a candidate-gene association study

Toll-like receptors (TLRs) and myeloid differentiation primary response protein 88 (MYD88) gene polymorphisms may be involved in the pathogenesis of Hodgkin's lymphoma (HL) through altered immunoregulatory and inflammatory responses. A candidate-gene association study was conducted to investigate the association between TLR9 -1237T>C, TLR9 2848A>G, MYD88 -938C>A and MYD88 1944C>G gene polymorphisms and the risk for HL. The impact of haplotypes was also examined. The study showed that carriership for -1237C and 2848A was associated with an increased risk for HL (odds ratio (OR)=2.53 (1.36-4.71) and OR=6.20 (1.3-28.8)). The MYD88 polymorphisms produced nonsignificant results. The estimated frequencies of the TLR9/1237C-2848A and MYD88/938C-1944G haplotypes were also significantly different between HL and controls (P<0.01). In addition, a significant difference between HL and controls was observed for the TLR9/1237C-TLR9/2848A-MYD88/938C-MYD88/1944C haplotypes (P<0.01). In conclusion, our study showed that TLR polymorphisms, and TLR9 and MYD88 haplotypes are related to the development of HL.

Current insight on trends, causes, and mechanisms of Hodgkin's lymphoma

Hodgkin's lymphoma (HL) has a unique and distinct history, epidemiology, treatment, and biology. A viral agent or infectious agent has long been considered as the etiologic agent and Epstein-Barr virus is the main candidate for the infectious agent causing HL; however, Epstein-Barr virus genome is found within the tumor in only about 20% to 40% of HL cases with a prior diagnosis of infectious mononucleosis. Recently, autoimmune and related conditions have drawn attention to a potential role for immune-related and inflammatory conditions in the etiology and pathogenesis of the malignancy. Evidence from multiply-affected families, a twin study, a case-control study, and population-based registry studies implicate genetic factors. Data from Eastern Asia and among Chinese immigrants in North America indicate increasing incidence trends for HL being associated with westernization. These results emphasize an interaction between environmental and genetic risk factors in HL.

Cancer risks among relatives of children with Hodgkin and non-Hodgkin lymphoma

A role for genetic susceptibility in the aetiology of childhood lymphomas was investigated in 454 families of children with histologically confirmed Hodgkin lymphoma (HL) and non-Hodgkin lymphoma (NHL) from Northwest England. Cancers in parents were obtained from the UK National Health Service Central Register and in other close relatives by interview with the parents. The cancer incidence among relatives was compared with expected incidence based on cancer registry data for England. There were 197 cancers in relatives (SIR 1.0 95% CI 0.8-1.1). In families of children with HL, there was an excess of HL in the first degree relatives (SIR 5.8 95% CI 1.2-16.9). Excesses of HL diagnosed under population median age (SIR 4.1 95% CI 1.1-10.6) were seen among all relatives and relatives of children who were below the median age at diagnosis (SIR 5.5 95% CI 1.1-16.0). In families of children with NHL, there were non-significant excesses of central nervous system (CNS) tumours in the first degree relatives (SIR 2.9 95% CI 0.8-7.4) and in the second and third degree relatives (SIR 1.5). There were significant excesses of CNS tumours diagnosed under the population median age (SIR 2.8 95% CI 1.1-5.8) in all relatives. Excess CNS tumours were also seen among relatives of children below the median age at diagnosis (SIR 3.2 95% CI 1.1-7.6). In conclusion, genetic susceptibility in some families of children with lymphoma might be operating, but aetiologies in HL and NHL appear to be different. Possible interpretations of our findings, in the context of putative genetic and infectious aetiologies, are discussed.

Survival patterns among lymphoma patients with a family history of lymphoma

PURPOSE

Genetic factors are important in the etiology and pathogenesis of chronic lymphocytic leukemia (CLL), Hodgkin's lymphoma (HL), and non-Hodgkin's lymphoma (NHL). Only a few small studies have assessed clinical characteristics and prognosis for familial patients, with inconsistent findings.

METHODS

Using population-based registries from Sweden and Denmark, 7,749 patients with CLL, 7,476 patients with HL, and 25,801 patients with NHL with linkable first-degree relatives were identified. Kaplan-Meier curves were constructed to compare survival in patients with lymphoma with and without a family history of lymphoma. The risk of dying was assessed using adjusted Cox proportional hazard models.

RESULTS

We found 85 patients with CLL (1.10%), 95 patients with HL (1.28%), and 206 patients with NHL (0.80%) with a family history of any lymphoma. Five-year mortality was similar for patients with CLL (hazard ratio [HR], 1.28; 95% CI, 0.95 to 1.72), HL (HR, 0.78; 95% CI, 0.49 to 1.25), and NHL (HR, 0.91; 95% CI, 0.74 to 1.12) versus without a family history of any lymphoma. Mortality was also similar for patients with versus without a family history of the same lymphoma. T-cell/anaplastic lymphoma patients with a family history of NHL had poorer outcome 5-years after diagnosis (HR, 5.38; 95% CI, 1.65 to 17.52). Results were similar for 10 years of follow-up.

CONCLUSION

With the exception of T-cell/anaplastic lymphoma, survival patterns for patients with CLL, HL, and NHL with a family history of lymphoma were similar to those for sporadic patients, suggesting that most familial lymphomas do not have an altered clinical course. Our findings provide no evidence to modify therapeutic strategies for patients with CLL, HL, or NHL based solely on family history.

New aspects in descriptive, etiologic, and molecular epidemiology of Hodgkin's lymphoma

Epstein-Barr virus (EBV) has remained the main candidate suggested as the infection causing Hodgkin's lymphoma for several years. However, EBV genome has been found only within the tumor in about 20%-40% of Hodgkin's lymphoma cases with a prior diagnosis of infectious mononucleosis. Recently, autoimmune and related conditions have drawn attention to a potential role for immune-related and inflammatory conditions in the etiology and pathogenesis of the malignancy. Evidence from multiple affected families from case series, a twin study, a case-control study, and population-based registry studies implicate a role for genetic factors. Simultaneously, data from Eastern Asia and among Chinese immigrants in North America indicate increasing incidence trends for Hodgkin's lymphoma being associated with westernization. These results emphasize an interaction between environmental and genetic risk factors in Hodgkin's lymphoma.

Short telomeres in aggressive non-Hodgkin's lymphoma as a risk factor in lymphomagenesis

OBJECTIVE

Telomeres cap chromosomal ends and help to maintain chromosomal integrity. Telomere shortening may result in chromosomal instability and, ultimately, malignant transformation of cells. It has not been systematically studied whether patients with malignancy have shortened telomeres in their normal, nontransformed cells, which might point to a preexisting disposition for chromosomal instability.

METHODS

We designed an (age-) matched pair analysis that compared telomere length in nonmalignant peripheral leukocytes from previously untreated patients who recently developed an aggressive non-Hodgkin's lymphoma, with leukocytes from healthy individuals.

RESULTS

Telomere lengths in B and T lymphocytes as well as granulocytes from the patients' group were significantly shorter than those from age-matched healthy controls. We were able to rule out increased proliferation, telomerase defects, or increased oxidative stress in patients as confounding factors of shortened telomeres.

CONCLUSION

Short telomeres in nontransformed leukocytes may constitute a risk factor for lymphomagenesis.

“Population Lab”: The Creation of Virtual Populations for Genetic Epidemiology Research

BACKGROUND

Studies of familial aggregation of disease routinely use linked population registers to construct retrospective cohorts. Although such resources have provided numerous estimates of familial risk, little is known regarding the sensitivity of the estimates to assumed disease models, changing demographics and incidence, and incompleteness of the data. Furthermore, there are no standard tools for testing the validity of estimates from standard epidemiologic designs and from new analytic strategies using register data.

METHODS

We present a method and a software package for simulating realistic populations of related individuals, using easily available vital statistics (population counts and fertility and mortality rates). The virtual population is stored in a pedigree file, allowing for easy retrieval of relatives and family structures. We simulate breast cancer in our population using age-specific incidence rates.

RESULTS

The Swedish population is simulated as dynamically evolving over the calendar period 1955-2002. The simulated and real population agree well on important features such as age profile, sibship size distribution, and average age at first birth. Using breast cancer as an example, we present several models of familial disease aggregation and show that the parameters used in the simulations are faithfully estimated. In addition, we illustrate how our simulated population provides insight into how incomplete family history in real register data can affect estimates of familial risk.

CONCLUSIONS

This simulation method can be used to investigate various underlying models of disease aggregation in families and enhance the development of optimal approaches for family studies. The software package, Population Lab, is available for free download (http://www.meb.ki.se/ approximately marrei/software/poplab/ and http://cran.at.r-project.org/).

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.

Family history of cancer in children with acute leukemia, Hodgkin's lymphoma or non-Hodgkin's lymphoma: the ESCALE study (SFCE)

The role of a family history of cancer in the etiology of childhood hematopoietic malignancies was investigated using the data from the ESCALE study. ESCALE, a population-based case-control study, was carried out in France over the period, 2003-2004. A total of 773 cases of acute leukemia (AL), 130 of Hodgkin's lymphoma (HL), 163 of non-Hodgkin's lymphoma (NHL) and 1,681 population-based controls were included. The controls were randomly selected from the French population and were frequency matched with the cases on age and gender. Cancer history in first- and second-degree relatives was reported by the mothers in a structured telephone questionnaire that was the same for the cases and controls. Odds ratios (ORs) were estimated using an unconditional regression model taking into account the stratification variables and potential confounders. A family history of cancer was associated with an increased risk of HL (OR = 1.5 [1.0-2.2]) and NHL (OR = 1.8 [1.3-2.5]), but not AL (OR = 1.0 [0.9-1.2]). The ORs were higher when at least 2 relatives had a history of cancer or when 1 case occurred before age 46 years. Only HL was significantly associated with a family history of hematopoietic malignancies (OR = 2.0 [1.0-3.8]), mainly because of a significant association with a history of HL (OR = 5.4 [1.3-22]). In conclusion, the study findings support the hypothesis of familial susceptibility to childhood lymphoma, but do not suggest familial susceptibility to childhood AL.

Anticipation in families with Hodgkin's and non-Hodgkin's lymphoma in their pedigree

Anticipation is an earlier onset and/or increasing severity in successive generations. This study was conducted to determine whether anticipation occurs in families that exhibit both Hodgkin's (HD) and non-Hodgkin's (NHL) lymphoma in their pedigrees. Nine published reports of multi-generational lymphoma and 33 previously unreported families with both lymphomas were analysed for evidence of anticipation. The difference between age at onset for each affected related pair was tested against the null hypothesis that there is no difference in age at onset. Differences between disease-free survival in affected generations were determined. These analyses were also conducted separately using only parent - child pairs with an age of onset above 25 years in an effort to avoid ascertainment bias. Age at onset in studied cases was also compared with the HD and NHL series from the Surveillance Epidemiology and End Results (SEER) Program of the US National Cancer Institute. The mean age at onset in the child and parent generations of all case families (60.2 and 35.7 years, respectively) and in the selected pairs (61.5 and 45.6, years) were significantly different (mean difference -24.5 years; P < 0.00001, and -15.9 years, P < 0.00001, respectively). Mean anticipation for parents with HD and children with NHL was -6.8 years (P = 0.01) for the unpublished and -14.4 years (P = 0.002) for the published families (overall anticipation -10.1 years). Mean anticipation for parents with NHL and children with HD was -34.4 years (P < 0.0001) for the unpublished and -32.7 years (P < 0.0001) for the published families (overall anticipation -34.2 years, P < 0.0001). The signed rank test rejected the null hypothesis which stated that there was no difference in age at onset between parents and children for overall, as well as selected pairs (P < 0.00001). The null hypothesis was also rejected for both the parents with HD/children with NHL group and the parents with NHL/children with HD group pairs (P < 0.0001). Age at onset distributions were significantly different for all generations with HD or NHL when compared to the SEER population (P < 0.00001), except for the parents with NHL, which showed no difference. In addition, this study reports four previously unpublished families with three generations of lymphoma in their pedigrees. These data suggest that anticipation occurs in families that exhibit both HL and NHL and that both neoplasms may have a common genetic basis.

Family history of hematopoietic and non-hematopoietic malignancies and risk of non-Hodgkin lymphoma

BACKGROUND

Family history of hematopoietic malignancies has been linked to the risk of non-Hodgkin lymphoma (NHL). The relationship between family history of specific hematopoietic and non-hematopoietic malignancies and the risk of NHL and by NHL subtypes are unclear.

METHODS

We analyzed data from a population-based case-control study in Connecticut women. A total of 601 histologically confirmed NHL incident cases and 717 randomly selected controls were included in the study. Unconditional logistic regression was used to estimate the association between family cancer history and risk of NHL overall and by NHL subtypes.

RESULTS

Compared to women who reported to have no family history of any malignancies in first-degree relatives, those who reported to have a family history of lymphoma (OR = 2.2, 95%CI: 1.1-4.5) or leukemia (OR = 2.5, 95%CI: 1.2-5.2) had an increased risk of NHL. The risk was higher among women who had a sibling with lymphoma or leukemia than those who had parents with lymphoma or leukemia. Several non-hematopoietic malignancies in first-degree relatives, including cancer of the lung (OR = 1.7, 95%CI: 1.1-2.6) in first-degree relatives, stomach (OR = 2.2, 95%CI: 0.8-5.9) and pancreas (OR = 2.6, 95%CI: 0.9-7.1) in parents, as well as liver (OR = 5.0, 95%CI: 1.0-24.6), breast (OR = 2.2, 95%CI: 1.3-3.9), cervix (OR = 7.5, 95%CI: 0.9-64.9), and ovary (OR = 3.5, 95%CI: 1.1-11.5) in siblings were also associated with an increased risk of NHL.

CONCLUSIONS

The risk associated with a family history of malignancies in first degree-relatives appears to vary by type of first-degree relatives.

Epidemiology and etiology of non-Hodgkin lymphoma--a review

The etiology of non-Hodgkin lymphoma, as well as its global dramatic rise in incidence during the past decades, remains largely unexplained. However, there is increasing awareness that this group of malignancies may entail not only clinical, morphological and molecular heterogeneity, but also considerable variations in terms of etiologic factors. In this review, epidemiologic patterns are summarized as well as current evidence of associations between various known or suspected risk factors for non-Hodgkin lymphoma overall or for any of its subtypes. Central pathogenetic mechanisms include immunosuppression, especially in relation to T-cell function and loss of control of latent EBV infection, and chronic antigen stimulation. Some degree of familiar aggregation also implies a role for genetic susceptibility. A number of recent investigations of non-Hodgkin lymphoma etiology will hopefully lead to a better understanding of the causes of these malignancies.

Autoimmunity and Susceptibility to Hodgkin Lymphoma: A Population-Based Case–Control Study in Scandinavia

BACKGROUND

Personal history of autoimmune diseases is consistently associated with increased risk of non-Hodgkin lymphoma. In contrast, there are limited data on risk of Hodgkin lymphoma following autoimmune diseases and almost no data addressing whether there is a familial association between the conditions.

METHODS

Using population-based linked registry data from Sweden and Denmark, 32 separate autoimmune and related conditions were identified from hospital diagnoses in 7476 case subjects with Hodgkin lymphoma, 18,573 matched control subjects, and more than 86,000 first-degree relatives of case and control subjects. We calculated odds ratios (ORs) and 95% confidence intervals (CIs) as measures of relative risks for each condition using logistic regression and also applied multivariable hierarchical regression models. All P values are two-sided.

RESULTS

We found statistically significantly increased risks of Hodgkin lymphoma associated with personal histories of several autoimmune conditions, including rheumatoid arthritis (OR = 2.7, 95% CI = 1.9 to 4.0), systemic lupus erythematosus (OR = 5.8, 95% CI = 2.2 to 15.1), sarcoidosis (OR = 14.1, 95% CI = 5.4 to 36.8), and immune thrombocytopenic purpura (OR = infinity, P = .002). A statistically significant increase in risk of Hodgkin lymphoma was associated with family histories of sarcoidosis (OR = 1.8, 95% CI = 1.01 to 3.1) and ulcerative colitis (OR = 1.6, 95% CI = 1.02 to 2.6).

CONCLUSIONS

Personal or family history of certain autoimmune conditions was strongly associated with increased risk of Hodgkin lymphoma. The association between both personal and family histories of sarcoidosis and a statistically significantly increased risk of Hodgkin lymphoma suggests shared susceptibility for these conditions.

Influence of familial cancer history on lymphoid neoplasms risk validated in the large European case-control study epilymph

Lymphomas have a potentially important familial component; large studies using recent classification systems are lacking. Based on a multicentre case-control study in seven European countries, we recruited 2480 cases of lymphoid neoplasms (LN) and 2540 controls, matched by country, age and sex. Diagnoses were established according to the World Health Organisation (WHO) classification. We estimated odds ratios (OR) and 95% confidence intervals (CI) for cancer in first-degree relatives and for the kind of relative affected. The OR of LN for a family history of haematological cancer was 1.6 (OR=1.2-2.1). The OR was particularly high for chronic lymphocytic leukaemia (CLL) (OR=2.9 [1.9-4.5]). A familial case of lymphoma increased the risk of Hodgkin's lymphoma (HL) (OR=3.4 [1.5-7.8]). No increased risk was observed for diffuse large B-cell and follicular lymphomas. For CLL and HL, the risk was similar in parents, offspring and siblings. Our study suggests familial aggregation of CLL with a family history of haematological cancer and of HL with a family history of lymphoma. The transmission pattern suggests a dominant model of heredity.

Familial risks and temporal incidence trends of multiple myeloma

In several cancer registration areas, the trends in the incidence and mortality of multiple myeloma (MM) have been rising over the last few decades. Pedigrees studies on families with multiple affected members have supported the hypothesis of a contributing hereditary etiology of MM due to shared genetic factors. The aim of our study was twofold: 1) to assess incidence trends of MM over the period 1961-2003 using national cancer registry data and; 2) to quantify the familial risk of MM using the 2004 update of the Swedish Family-Cancer Database. For men, the age-standardized rates were 4.33 per 100,000 in 1961-65 and 4.79 in 2001-03. The corresponding rates for women were 2.76 and 3.43. In the elderly, MM rates have risen from 28.7 per 100,000 to 36.2 in men, and from 20.2 to 24.5 in women. MM clustered in families with MM (standardized incidence ratio, SIR=2.45), non-Hodgkin lymphoma (SIR=1.34) and chronic lymphocytic leukaemia (SIR=2.45). No association was found for Hodgkin lymphoma and other leukaemias. Significant associations were found for rectal, stomach, cervical, prostate, bladder, endocrine glands and connective tissue malignancies. Our study adds further evidence that the incidence of MM in Sweden has been constant for several decades. The apparent increase observed in the elderly is, at least in part, attributable to improved diagnostics and certification. MM aggregates in families with MM, chronic lymphocytic leukaemia and, to a lesser extent, with non-Hodgkin lymphoma. If environmental factors can be excluded, the pattern of familial risk of MM is consistent with an autosomal dominant mode of inheritance.

Family history of hemolymphopoietic and other cancers and risk of non-Hodgkin's lymphoma

We investigated the risk of lymphomas, hemolymphopoietic (HLP) cancers (including lymphomas), and non-HLP cancers in first-degree relatives of non-Hodgkin's lymphoma (NHL) cases in an Italian case-control study on 225 patients (median age, 59 years) with a new diagnosis of NHL and 504 hospital controls (median age, 63 years), admitted for a wide spectrum of acute, nonneoplastic, nonimmune conditions. We estimated odds ratios (OR) adjusted for sex, age, family size, and other potential confounders. We also built the cohort of all first-degree relatives and computed age and sex adjusted hazard ratios (HR) using proportional hazard models. A history of lymphoma in first-degree relatives was reported by 5 NHL cases and 3 controls [OR, 3.2; 95% confidence interval (95% CI), 0.7-14.4] whereas 14 cases and 11 controls reported a family history of HLP cancers (OR, 3.0; 95% CI, 1.2-7.0). The HR of relatives of NHL cases, compared with relatives of controls, was 4.5 (95% CI, 1.1-18.8) for lymphomas, 3.5 (95% CI, 1.5-7.4) for HLP cancers, 1.6 (95% CI, 1.3-2.0) for all cancers, and 1.0 (95% CI, 0.9-1.1) for all causes of deaths. The HRs were higher for relatives of NHL cases diagnosed before the age of 50 years: 7.1 for HLP cancers, 2.0 for all cancers, and 1.6 for all deaths. A family history of cancer of the liver (OR, 2.1; 95% CI, 1.0-4.2), breast (OR, 2.0; 95% CI, 1.0-3.6), and kidney (OR, 4.6; 95% CI, 1.0-20.9) increased NHL risk. The OR was also elevated for all cancer sites (OR, 1.7 95% CI, 1.2-2.4) and the risk increased with the number of affected relatives also when HLP cancers were excluded.

Reliability of Self-Reported Family History of Cancer in a Large Case–Control Study of Lymphoma

BACKGROUND

Case-control studies of familial cancer risk traditionally rely on self-reported family history of cancer, which may bias results due to differential recall between case patients and control subjects. To evaluate the reliability of self-reported data, we analyzed questionnaire and registry-based data on familial cancer from a population-based case-control study of malignant lymphoma.

METHODS

All 1508 lymphoma case patients and 1229 control subjects completed a telephone interview assessing cancer in family members. Participants were linked to the Swedish Multi-Generation Register and Cancer Register to identify confirmed cancer diagnoses in first-degree relatives. The sensitivity and specificity of self-reported familial cancer were calculated among case patients and control subjects and were compared using logistic regression. All statistical tests were two-sided.

RESULTS

Lymphoma case patients reported a family history of any cancer with statistically significantly higher sensitivity than control subjects (0.85, 95% confidence interval [CI] = 0.83 to 0.87 and 0.80, 95% CI = 0.77 to 0.82, respectively) but with marginally lower specificity (0.89, 95% CI = 0.87 to 0.91 and 0.92, 95% CI = 0.90 to 0.94, respectively). The sensitivity of self-reporting familial cancers by site ranged from less than 0.20 for rare malignancies to nearly 0.75 for more common types, whereas specificity was generally 0.98 or greater. For most sites, the reliability of self-report was similar in patients and control subjects. However, patients reported familial hematopoietic cancer with statistically significantly higher sensitivity (0.60, 95% CI = 0.57 to 0.62) than control subjects (0.38, 95% CI = 0.35 to 0.40). Odds ratios for the association between familial cancer and risk of non-Hodgkin lymphoma were consistently higher when based on self-reported, compared with registry data-based, family history of any cancer or of hematopoietic cancer.

CONCLUSIONS

Reliability of self-reported family history of cancer varies between case patients and control subjects. Recall bias may thus produce biased results in case-control studies of familial cancer risk.

Family history of hematopoietic malignancy and risk of lymphoma

BACKGROUND

A family history of hematopoietic malignancy is associated with an increased risk of non-Hodgkin lymphoma (NHL) and Hodgkin lymphoma (HL), although the magnitude of the relative risk is unclear. We estimated the association between familial hematopoietic cancer and risk of lymphoma using validated, registry-based family data, and we also investigated whether associations between some environmental exposures and risk of lymphoma vary between individuals with and without such a family history.

METHODS

In a population-based case-control study of malignant lymphoma, 1506 case patients and 1229 control subjects were linked to the Swedish Multi-Generation Register and then to the Swedish Cancer Register to ascertain history of cancer in first-degree relatives of patients with malignant lymphoma. Multiple logistic regression was used to estimate odds ratios (ORs) and 95% confidence intervals (CIs) for associations with the risk of lymphoma.

RESULTS

A history of hematopoietic malignancy in any first-degree relative was associated with an increased risk of all NHL (OR = 1.8, 95% CI = 1.2 to 2.5), common B-cell NHL subtypes, and HL. Relative risks were generally stronger in association with sibling hematopoietic cancer (OR for all NHL = 3.2, 95% CI = 1.3 to 7.6) than with parental hematopoietic cancer (OR = 1.6, 95% CI = 1.1 to 2.3). A family history of NHL or chronic lymphocytic leukemia (CLL) was associated with an increased risk of several NHL subtypes and HL, whereas familial multiple myeloma was associated with a higher risk of follicular lymphoma. There was no statistically significant heterogeneity in NHL risk associations with environmental factors between individuals with and without familial hematopoietic malignancy.

CONCLUSIONS

The increased risk of NHL and HL among individuals with a family history of hematopoietic malignancy was approximately twofold for both lymphoma types. There was no evidence that etiologic associations varied between familial NHL and nonfamilial NHL.

Familial risk for non-Hodgkin lymphoma and other lymphoproliferative malignancies by histopathologic subtype: the Swedish Family-Cancer Database

Non-Hodgkin lymphoma (NHL) consists of a heterogeneous group of tumors. Population-based data on the familial risk for specific histopathologic subtypes have not been established. Such data are useful for clinical counseling and for searching tumor subtypes sharing common genetic pathways. We used the Swedish Family-Cancer Database to calculate standardized incidence ratios (SIRs) for histopathology-specific subtypes of NHL in 4455 offspring with NHL whose parents or siblings were affected with different types of lymphoproliferative malignancies. A familial history of NHL significantly increased the risk for NHL (SIRparent = 1.8; SIRsibling = 1.9) and for diffuse large B-cell lymphoma (SIRparent = 2.3), follicular lymphoma (SIRsibling = 2.3), and B-cell lymphoma not otherwise specified (NOS) (SIRsibling = 3.4). For a parental history of histopathology-specific concordant cancer, the risks were significantly increased for diffuse large B-cell lymphoma (SIR = 11.8), follicular NHL (SIR = 6.1), plasma cell myeloma (SIR = 2.5), and chronic lymphocytic leukemia (SIR = 5.9). Familial clusters for NHL seemed stronger in females and in siblings. Our study provides the first quantification of the familial risks for NHL by histopathology. The present findings give evidence for a strong familial association of NHL, with little differences in the magnitude of risks for various histopathologic subtypes. The patterns of risks in parents and siblings support the hypothesis of an autosomal-dominant component for diffuse large B-cell NHL and a recessive one for follicular NHL.

Transmission of donor illness by stem cell transplantation: should screening be different in older donors?

With increasing donor age, the potential of transmitting diseases from donor to recipient reaches new dimensions. Potentially transmittable diseases from donors include infections, congenital disorders, and acquired illnesses like autoimmune diseases or malignancies of hematological or nonhematological origin. While established nonmalignant or malignant diseases might be easy to discover, early-stage hematological diseases like CML, light-chain multiple myelomas, aleukemic leukemias, occult myelodysplastic syndromes and other malignant and nonmalignant diseases might not be detectable by routine screening but only by invasive, new and/or expensive diagnostic tests. In the following article, we propose recommendations for donor work-up, taking into consideration the age of the donors. In contrast to blood transfusions, stem cells from donors with abnormal findings might still be acceptable for HCT, when no other options are available and life expectancy is limited. This issue is discussed in detail in relation to the available donor and stem cell source. Finally, the recommendations presented here aim at harmonized worldwide work-up for donors to insure high standard quality.

The epidemiology of non-Hodgkin's lymphoma

The incidence of non-Hodgkin's lymphoma (NHL) has doubled over the past two decades in the US and most other westernized countries. While improved cancer reporting, changes in lymphoma classification, and increases in AIDS-associated lymphomas have contributed to the startling escalation of disease incidence, these factors are estimated to account for only about 50% of the increase in observed incidence. The elucidation of etiologic factors and their mechanistic role in the pathogenesis of this malignancy are critical to advancements in disease prevention and treatment. Current evidence suggests that factors/conditions that precipitate either chronic antigenic stimulation or immunosuppression may provide a preferential milieu for development of NHL. High rates of lymphoma have been observed among individuals with autoimmune disease, organ transplants, and primary or acquired immunodeficiencies. Ultraviolet radiation, previously demonstrated to have an immunosuppressive effect, has also been suggested as a possible risk factor for NHL. Several pathogens have been linked to the risk of lymphoma, including Epstein-Barr virus, human immunodeficiency virus, human T-cell lymphotropic virus-1, Helicobacter pylori, hepatitis C, and simian virus 40. Whether these microbes are responsible for specific genetic mutations that initiate tumor growth, antigenic stimulation leading to B-cell proliferation, and increased potential of random cell replication errors, or immunosuppression, which thereby promotes tumor growth, has not been clearly delineated. Other exogenous factors which have been implicated in lymphomagenesis are chemicals and agricultural exposures, hair dyes, and blood transfusions. We must build on our current knowledge regarding the etiology of NHL in order that prevention, treatment, and ultimately, cure of this malignancy becomes a reality.

Risk of Non-Hodgkin's Lymphoma and Family History of Lymphatic, Hematologic, and Other Cancers

Background: An elevated risk of developing non-Hodgkin's lymphoma (NHL) has been associated with a family history of NHL and several other malignancies, but the magnitude of risks and mechanisms are uncertain. Methods: We used self-reported family history data from a recent multicenter U.S.-based case-control studies of NHL to evaluate familial aggregation of NHL with various hematolymphoproliferative and other cancers. Estimates of familial aggregation were obtained as hazard ratios (HR) that compare incidence of different cancers in first-degree relatives of NHL cases with that in the first-degree relatives of NHL controls. Limitations of the study included low participation rates (76% for cases and 52% for controls) and potential differential accuracy of recall. Results: Risk of NHL was elevated in relatives of NHL cases [HR, 2.9; 95% confidence interval (95% CI), 0.95–8.53]; the aggregation seems to be stronger for siblings (HR, 7.6; 95% CI, 0.98–58.8) and for male relatives (HR, 6.2; 95% CI, 0.77–50.0). Risk of Hodgkin's lymphoma seems to be also elevated among relatives of early-onset (&lt;50 years) NHL cases (HR, 3.2; 95% CI, 0.88–11.6). Evaluation of family history of other cancers provided modest evidence for an increased risk of melanoma of the skin (HR, 2.9; 95% CI, 1.08–7.75), pancreatic cancer (HR, 2.1; 95% CI, 0.96–4.43), stomach cancer (HR, 1.8; 95% CI, 0.91–3.63), and prostate cancer (HR, 1.3; 95% CI, 0.87–1.99). Conclusions: These results are consistent with previous findings of familial aggregation of NHL, Hodgkin's lymphoma, and a few other cancers. The pattern of male-specific and sibling-specific familial aggregation of NHL we observed, if confirmed, may shed new light on the possible mechanisms that underlie familial aggregation of the disease.

Clinical characteristics of familial vs. sporadic non-Hodgkin lymphoma in patients diagnosed at the Mayo Clinic (1986-2000)

There are few data on the clinical characteristics of familial vs. sporadic non-Hodgkin lymphoma (NHL). Using the NHL registry at the Mayo Clinic, we compared age of diagnosis, gender, tumor site and histologic subtype between patients with sporadic and familial NHL. In 2001, we identified all new cases of adult NHL diagnosed between 1986 and 2000 in the Mayo Clinic NHL database (n = 2289) and mailed out a family history questionnaire to all living patients with a current address (n = 1043). Each NHL patient was categorized according to their self-report of leukemia or lymphoma in first-degree (1 degree) relatives. We received complete FH information on 740 patients (71%). Age at diagnosis of NHL ranged from 18-88 years (mean = 59 years) and 53% of our cases were male. First-degree FH of lymphoma was reported by 43 patients (6%), 1 degree FH of leukemia by 27 patients (4%) and 1 degree FH of both in 4 (1%). There was a nonstatistically significant later age at diagnosis for cases with any family history of lymphoma or leukemia (mean age = 61.3 and 61.7 years, respectively) vs. no family history (59.0 years) (P = 0.58). The male to female ratio for those with a FH of leukemia (ratio = 2.9) was higher compared to those with FH lymphoma (0.95) or no FH (1.1) (P = 0.08). No differences were apparent between 1 degree FH and site of NHL (nodal vs. extranodal) (P = 0.53). Among recently diagnosed cases (since 1995), there was some suggestion of a greater proportion of aggressive tumors for those with any family history (69% and 55%) vs. none (50%) (P = 0.20). We found little evidence of large differences between familial and sporadic NHL with regard to age, gender, site or histologic subtype.

Familial aggregation of Hodgkin lymphoma and related tumors

BACKGROUND

The importance of genetic factors in the etiology of Hodgkin lymphoma (HL) has been suggested by family and population studies. However, the spectrum of malignancies associated with common genetic etiology and the effects of gender and age on familial risk have not been established.

METHODS

Diagnoses of lymphoproliferative malignancies were compared in 15,799 first-degree relatives of 5047 patients with HL versus 32,117 first-degree relatives of 10,078 control probands from Sweden and in 7185 first-degree relatives of 2429 patients with HL versus 27,434 first-degree relatives of 8,495 control probands from Denmark using marginal survival models.

RESULTS

The risk of HL in relatives of patients with HL was increased significantly in both populations, with relative risks of 3.47 (95% confidence interval [95% CI], 1.77-6.80) in Sweden and 2.55 (95% CI, 1.01-6.45) in Denmark and a pooled estimate of 3.11 (95%CI, 1.82-5.29). In Sweden, risks for relatives of patients also were increased significantly for chronic lymphocytic leukemia and non-Hodgkin lymphoma (in males). Relative risks were higher in males compared with females and in siblings of patients compared with parents and offspring of patients. Relatives of patients with earlier-onset disease were at higher risk for HL.

CONCLUSIONS

HL has an important familial component, which is stronger in families of affected individuals age < 40 years, in males, and in siblings, and it is shared with some (but not other) lymphoproliferative malignancies. The cumulative lifetime risks are very small, however, for the development of HL de novo or in first-degree relatives of affected patients.

Agricultural Pesticide Use, Familial Cancer, and Risk of Non-Hodgkin Lymphoma

To investigate whether the association between agricultural pesticide use and the risk of non-Hodgkin's lymphoma (NHL) is modified by a family history of hematopoietic cancer, including leukemia, myeloma, and lymphoma, we analyzed pooled data on white men from three population-based, case-control studies of NHL conducted in Iowa/Minnesota, Kansas, and Nebraska. Information on the agricultural use of insecticides, fungicides, and herbicides; a family history of cancer; and other risk factors was obtained by interviewing 973 cases and 2,853 controls or, if deceased, their next-of-kin (37% of cases, 43% of controls). The NHL risk was estimated by odds ratios (ORs) and 95% confidence intervals (CIs), adjusted for age, state of residence, type of respondent, and use of hair dye. Compared to men with no family history of cancer, the ORs (95% CIs) of NHL was 1.5 (1.3–1.8) for men with a family history of nonhematopoietic cancer, and 2.7 (1.9–3.7) for those with a history of hematopoietic cancer among first-degree relatives. This positive association was noted for each group of NHL defined according to the Working Formulation, and was most pronounced for small lymphocytic NHL. Among direct respondents, farmers who used pesticides and had a positive family history of cancer or hematopoietic cancer were not at elevated risk of NHL, compared to nonfarmers who had no family cancer history. However, among proxy respondents, ORs were elevated for farmers who had a positive family history of hematopoietic cancer and used animal insecticides (OR = 4.6; 1.9–11.2), crop insecticides (OR = 4.7; 1.6–13.4), or herbicides (OR = 4.9; 1.7–14.2), although the interaction of family history of cancer and agricultural pesticide use was not statistically significant. In summary, the joint effects of the family cancer history and pesticide use were limited to proxy respondents with wide CIs and, thus, provide little evidence that a family history of cancer modifies the association of agricultural exposures with NHL.

Bone marrow aspirates as part of routine donor assessment for allogeneic blood and marrow transplantation can reveal presence of occult hematological malignancies in otherwise asymptomatic individuals

Pre transplant screening work-up of donors for allogeneic blood and marrow transplantation is essential in an effort to minimize risks to the recipient and protect the donor. At Princess Margaret Hospital, every potential donor is screened with a bone marrow aspirate. The case histories of three asymptomatic potential donors who presented within 1 year with normal complete blood counts, history and physical examination are presented. A 65-year-old male patient was diagnosed with smouldering multiple myeloma, a 72-year-old male patient with chronic lymphocytic leukemia and a 42-year-old male patient with myelodysplastic syndrome. Bone marrow examination led to the diagnosis in each one of these cases. Of note is that each of the potential donors was discovered to have the same disease as the transplant recipient. In vitro clonogenic hemopoietic progenitor assays were compared to those of 20 normal volunteers. Inferior growth of hemopoietic progenitor colonies in all three was noted. In conclusion, particularly in older donors and donors with potential for familial malignancies, more screening investigations including bone marrow aspiration may be reasonable to investigate for occult hematological malignancies prior to stem cell donation. Clonogenic assays can contribute to detect hemopoietic abnormalities pre transplant.

Malignant tumors in first-degree relatives of cancer patients aged 0-25 years (province of Trieste, Italy)

To determine whether the occurrence of first and second primary malignancies in first-degree relatives of cancer patients aged 0-25 years (probands) differed from that in the general population, a cohort study was carried out on 860 relatives of 265 probands living in the province of Trieste, Italy. During the follow-up period (median duration = 28 years, 25th-75th percentile = 20-34), the relatives developed 103 first primary cancers vs. 88.9 expected for a standardized incidence ratio (SIR) of 1.2 (p = 0.2). Significantly elevated risks were found for melanoma in the parents of probands aged 15-25 years with melanoma (SIR = 15.0, p = 0.002), for hemolymphatic malignancies in the fathers of probands aged 0-14 years with brain tumors (SIR = 13.3, p = 0.0005) and for hemolymphatic cancers in relatives as a whole of probands aged 15-25 years with lymphomas (SIR = 4.5, p = 0.01). During the follow-up period, 7 relatives with a first primary cancer had a subsequent malignancy vs. 4.2 expected for an SIR of 1.7 (p = 0.3). Our results indicate that young cancer patients per se should not to be considered as a factor that usually increases the risk of developing malignant tumors among their first-degree relatives, except when a known cancer family syndrome or predisposition is recognized.

Analysis of mismatch repair defects in the familial occurrence of lymphoma and colorectal cancer

Hereditary non-polyposis colon cancer (HNPCC) is an autosomal dominant disorder featuring familial clustering of colorectal and/or endometrial cancer, and other malignancies. Except for a rare case report, Hodgkin's disease (HD) and non-Hodgkin's lymphoma (NHL) have not been considered part of HNPCC. Recent murine models for HNPCC have shown an increased incidence of B- and T-cell lymphoma, as well as tumors of the gastrointestinal tract and other organ systems, involving defects in genes resulting in faulty mismatch repair (MMR) of DNA. These MMR genes include MLH1, MSH2, MSH3, MSH6, PMS1 and PMS2. We sought to analyze the occurrence of NHL and HD in families with clusters of colorectal cancers (CRC). Probands from 21 kindreds were classified as HNPCC (3), HNPCC-like (5), and HNPCC-variant (13); seen and followed by Clinical Genetics at Memorial Hospital the kindreds were assessed for the occurrence of NHL or HD. Of the 21 pedigrees, a total of 37 patients were identified who were diagnosed with leukemia, lymphoma, or HD. Fourteen of the 37 patients with a diagnosis of NHL or HD were further classified and showed varying histologies ranging from chronic lymphocytic leukemia/small lymphocytic lymphoma (2), mycosis fungoides (1), follicular lymphoma (1), extranodal marginal zone lymphoma of MALT type (2), diffuse large B-cell lymphoma (4), nodular sclerosis HD (3), and mixed cellularity HD (1). Microsatellite instability studies were performed on 6 cases but none showed evidence of replication error repair defects. Immunohistochemical stains performed on paraffin sections from these 6 representative cases showed differential protein expression of MLH1, MSH2, MSH6, and PMS2 when compared to normal reactive tissues from the same patient but showed no significant differences when compared to controls of non-familial, sporadic lymphomas. These results suggest that lymphomas arising in the setting of familial CRC do not bear the molecular hallmarks of HNPCC. Further studies are needed to explain the differential patterns of expression of RER-associated proteins in lymphomas, as well as the association of lymphomas and possibly renal cell cancers in a subset of kindreds in which CRC clustering is evident.

Update on epidemiology and therapeutics for non-Hodgkin's lymphoma

This chapter presents updated information on the trends and patterns of non-Hodgkin's lymphoma (NHL) diagnoses as well as new information on chemotherapeutic and immunotherapeutic options for NHL treatment. In Section I, Dr. Brian Chiu summarizes the current knowledge regarding the etiologic factors and patterns of NHL as well as suggests future epidemiologic studies based on these preliminary results. In Section II, Dr. Bruce Cheson and colleagues outline new chemotherapeutic and small molecule antineoplastic agents with unique mechanisms of action such as protease inhibitors, farnesyl transferase or histone deacetylase inhibitors, and antisense oligonucleotides. In Section III, Dr. Julie Vose reviews the anti-lymphoma effects of monoclonal antibodies, radioimmunoconjugates, idiotype vaccines, and immunologic enhancing adjuvants with respect to mechanisms of action, clinical trials, and their potential for patient therapy.