Familial risk of cancer: Data for clinical counseling and cancer genetics

Family History of Cancer is associated with poorer prognosis in Oral Squamous Cell Carcinoma

OBJECTIVE

The purpose of this study was to investigate the prognostic value of the family history of cancer (FHC) in predicting survival and clinicopathological features in oral squamous cell carcinoma (OSCC) patients.

MATERIALS AND METHODS

This single-institution study utilized data from 610 patients undergoing surgery from 2014 to 2020 that was prospectively collected and cataloged for research purposes. All patients underwent standard surgery with/without radiotherapy or chemoradiotherapy. We statistically evaluated whether FHC was associated with changes in disease-free survival (DFS) and disease-specific survival (DSS).

RESULTS

Among 610 patients, 141 (23.1%) reported a family history of cancer. The distribution of clinicopathological characteristics was balanced between FHC-positive and FHC-negative OSCC patients. FHC-positive patients had decreased DFS (P=0.005) and DSS (P=0.018) compared to FHC-negative patients.

CONCLUSIONS

FHC-positive OSCC patients have a poorer prognosis. FHC positivity is an independent predictor of negative outcomes based on DFS and DSS. FHC should be a consideration in screening, evaluating, counseling, and treating OSCC patients.

Prevalence of Heavy Chain MGUS by Race and Family History Risk Groups Using a High Sensitivity Screening Method

The mass spectrometry assay found over threefold numbers of individuals with MGUS than gel-based assays across 3 risk groups.

Relative differences in MGUS using the sensitive mass spectrometry assay were similar by race, family history, and age as prior MGUS studies.

Mass-spectrometry (MS) assays detect lower levels of monoclonal proteins and result in earlier detection of monoclonal gammopathy of undetermined significance (MGUS). We examined heavy chain MGUS prevalence using matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF) MS among 3 risk groups, ages 50 or older: 327 African Americans (AA) and 1223 European Americans (EA) from a clinical biobank and 1093 unaffected first-degree relatives (FDR) of patients with hematologic disorders. Age- and sex-adjusted prevalence rates were directly standardized to 2010 United States population. Prevalence ratios were estimated for comparisons of AA and FDR to the EA group using the Poisson distribution. Results were also compared with population-based prevalence using conventional gel-based methods. Risk groups had similar sex and age distributions. MALDI-TOF MGUS prevalence was higher in the AA (16.5% [95% confidence interval (CI), 12.2%, 20.8%]) and FDR (18.3% [95% CI, 16.6%, 21.6%]) than in EA (10.8% [95% CI, 8.8%, 12.7%]), translating to prevalence ratios of 1.73 (95% CI, 1.31, 2.29) and 1.90 (95% CI, 1.55, 2.34), respectively. MALDI-TOF EA prevalence was over threefold higher than conventional estimates but showed similar age trends. Thus, the MALDI-TOF assay found greater numbers with MGUS but similar relative differences by race, family history, and age as prior studies.

Epidemiology, genetics and treatment of multiple myeloma and precursor diseases

Multiple myeloma (MM) is a hematological malignancy caused by the clonal expansion of plasma cells. The incidence of MM worldwide is increasing with greater than 140 000 people being diagnosed with MM per year. Whereas 5-year survival after a diagnosis of MM has improved from 28% in 1975 to 56% in 2012, the disease remains essentially incurable. In this review, we summarize our current understanding of MM including its epidemiology, genetics and biology. We will also provide an overview of MM management that has led to improvements in survival, including recent changes to diagnosis and therapies. Areas of unmet need include the management of patients with high-risk MM, those with reduced performance status and those refractory to standard therapies. Ongoing research into the biology and early detection of MM as well as the development of novel therapies, such as immunotherapies, has the potential to influence MM practice in the future.

Sequencing at lymphoid neoplasm susceptibility loci maps six myeloma risk genes

Inherited genetic risk factors play a role in multiple myeloma (MM), yet considerable missing heritability exists. Rare risk variants at genome-wide association study (GWAS) loci are a new avenue to explore. Pleiotropy between lymphoid neoplasms (LNs) has been suggested in family history and genetic studies, but no studies have interrogated sequencing for pleiotropic genes or rare risk variants. Sequencing genetically enriched cases can help discover rarer variants. We analyzed exome sequencing in familial or early-onset MM cases to identify rare, functionally relevant variants near GWAS loci for a range of LNs. A total of 149 distinct and significant LN GWAS loci have been published. We identified six recurrent, rare, potentially deleterious variants within 5 kb of significant GWAS single nucleotide polymorphisms in 75 MM cases. Mutations were observed in BTNL2, EOMES, TNFRSF13B, IRF8, ACOXL and TSPAN32. All six genes replicated in an independent set of 255 early-onset MM or familial MM or precursor cases. Expansion of our analyses to the full length of these six genes resulted in a list of 39 rare and deleterious variants, seven of which segregated in MM families. Three genes also had significant rare variant burden in 733 sporadic MM cases compared with 935 control individuals: IRF8 (P = 1.0 × 10-6), EOMES (P = 6.0 × 10-6) and BTNL2 (P = 2.1 × 10-3). Together, our results implicate six genes in MM risk, provide support for genetic pleiotropy between LN subtypes and demonstrate the utility of sequencing genetically enriched cases to identify functionally relevant variants near GWAS loci.

Evaluating polygenic risk scores in assessing risk of nine solid and hematologic cancers in European descendants

Genome-wide association studies (GWAS) have identified many genetic risk variants for cancers. The utility of these variants in assessing risk of esophageal, gastric and endometrial cancers, as well as melanoma, glioma, diffuse large B-cell lymphoma, follicular lymphoma, chronic lymphoid leukemia and multiple myeloma, has not been adequately investigated. We constructed a site-specific polygenic risk score (PRS) for each of these nine cancers using their GWAS-identified risk variants. Using data from 400 807 participants of European descent in the UK Biobank, a population-based cohort study, we estimated the hazard ratios of each cancer associated with its PRS using Cox proportional hazard models. During a median follow-up of 5.8 years, 3905 incident cases of these nine cancers were identified in the cohort. The area under the receiver operating characteristic curve ranged from 0.53 to 0.69 for these cancers. Except for esophageal cancer, significant dose-response associations were observed between PRS and cancer risk. Compared to individuals in the middle quintile (40%-60%) at an average risk, those among the highest 5% of the PRS had a twofold elevated risk of melanoma, glioma, follicular lymphoma or multiple myeloma, and a fourfold elevated risk of chronic lymphoid leukemia. Using PRS, 63.0% of the participants could be classified as having an over twofold elevated risk for at least one cancer. The PRS derived using risk variants identified to date by GWAS showed the potential in identifying individuals at a significantly elevated risk of cancer for prevention.

Increased Cancer Risk in Families with Pediatric Cancer Is Associated with Gender, Age, Diagnosis, and Degree of Relation to the Child

BACKGROUND

Studies of cancer risk among relatives of children with cancer beyond parents and siblings are limited. We have investigated the cancer risk up to the third degree of relation in families with pediatric cancer to reveal patterns of inheritance.

METHODS

A single-center cohort of 757 patients with pediatric cancer was linked to the Swedish National Population Register, resulting in 16,137 relatives up to the third degree of relation. All relatives were matched to the Swedish Cancer Register, and standard incidence ratios (SIR) were calculated to define relatives at risk.

RESULTS

Children and adults up to the third degree of relation had increased cancer risk, with SIRs of 1.48 (P = 0.01) and 1.07 (P < 0.01), respectively. The SIRs for first- and third-degree adult relatives were 1.22 and 1.10, respectively, but no increased risk was observed in second-degree relatives. Male relatives had a higher risk than females, especially when related to a girl and when the child had leukemia. The risk was mainly increased for lung, prostate, and gastrointestinal cancer. When excluding 29 families of children with known pathogenic germline variants, the increased risk remained.

CONCLUSIONS

Relatives to children with cancer up to third degree of relation have an increased cancer risk. Known pathogenic germline variants do not explain this increased risk.

IMPACT

The overall increased cancer risk among relatives of children with cancer in this population-based cohort strengthens the importance of surveillance programs for families with pediatric cancer.

Genetic predisposition for multiple myeloma

Multiple myeloma (MM) is the second most common blood malignancy. Epidemiological family studies going back to the 1920s have provided evidence for familial aggregation, suggesting a subset of cases have an inherited genetic background. Recently, studies aimed at explaining this phenomenon have begun to provide direct evidence for genetic predisposition to MM. Genome-wide association studies have identified common risk alleles at 24 independent loci. Sequencing studies of familial cases and kindreds have begun to identify promising candidate genes where variants with strong effects on MM risk might reside. Finally, functional studies are starting to give insight into how identified risk alleles promote the development of MM. Here, we review recent findings in MM predisposition field, and highlight open questions and future directions.

Analysis of 153 115 patients with hematological malignancies refines the spectrum of familial risk

Estimating familial cancer risks is clinically important in being able to discriminate between individuals in the population at differing risk for malignancy. To gain insight into the familial risk for the different hematological malignancies and their possible inter-relationship, we analyzed data on more than 16 million individuals from the Swedish Family-Cancer Database. After identifying 153 115 patients diagnosed with a primary hematological malignancy, we quantified familial relative risks (FRRs) by calculating standardized incident ratios (SIRs) in 391 131 of their first-degree relatives. The majority of hematological malignancies showed increased FRRs for the same tumor type, with the highest FRRs being observed for mixed cellularity Hodgkin lymphoma (SIR, 16.7), lymphoplasmacytic lymphoma (SIR, 15.8), and mantle cell lymphoma (SIR, 13.3). There was evidence for pleiotropic relationships; notably, chronic lymphocytic leukemia was associated with an elevated familial risk for other B-cell tumors and myeloproliferative neoplasms. Collectively, these data provide evidence for shared etiological factors for many hematological malignancies and provide information for identifying individuals at increased risk, as well as informing future gene discovery initiatives.

Familial Cancer Clustering in Urothelial Cancer: A Population-Based Case-Control Study

Background

Family history of bladder cancer confers an increased risk for concordant and discordant cancers in relatives. However, previous studies investigating this relationship lack any correction for smoking status of family members. We conducted a population-based study of cancer risks in relatives of bladder cancer patients and matched controls with exclusion of variant subtypes to improve the understanding of familial cancer clustering.

Methods

Case subjects with urothelial carcinoma were identified using the Utah Cancer Registry and matched 1:5 to cancer-free controls from the Utah Population Database. Cox regression was used to determine the risk of cancer in first-degree relatives, second-degree relatives, first cousins, and spouses. A total of 229 251 relatives of case subjects and 1 197 552 relatives of matched control subjects were analyzed. To correct for smoking status, we performed a secondary analysis excluding families with elevated rates of smoking-related cancers. All statistical tests were two-sided.

Results

First- and second-degree relatives of case subjects had an increased risk for any cancer diagnosis (hazard ratio [HR] = 1.06, 95% confidence interval [CI] = 1.03 to 1.09, P < .001; HR = 1.04, 95% CI = 1.02 to 1.07, P = .001) and urothelial cancer (HR = 1.73, 95% CI = 1.50 to 1.99, P < .001; HR = 1.35, 95% CI = 1.21 to 1.51, P < .001). Site-specific analysis found increased risk for bladder (HR = 1.69, 95% CI = 1.47 to 1.95, P < .001), kidney (HR = 1.30, 95% CI = 1.08 to 1.57, P = .006), cervical (HR = 1.25, 95% CI = 1.06 to 1.49, P = .01), and lung cancer (HR = 1.34, 95% CI = 1.19 to 1.51, P < .001) in first-degree relatives. Second-degree relatives had increased risk for bladder (HR = 1.35, 95% CI = 1.2 to 1.5, P < .001) and thyroid cancer (HR = 1.18, 95% CI = 1.03 to 1.35, P = .02). Spouses showed an increased risk for laryngeal (HR = 2.68, 95% CI = 1.02 to 7.05, P = .04) and cervical cancer (HR = 1.57, 95% CI = 1.13 to 2.17, P = .007). These results did not substantively change after correction for suspected smoking behaviors.

Conclusion

Our results suggest familial urothelial cancer clustering independent of smoking, with increased risk in relatives for both concordant and discordant cancers, suggesting shared genetic or environmental roots. Identifying families with statistically significant risks for non-smoking-related urothelial cancer would be extremely informative for genetic linkage studies.

Risk of MGUS in relatives of multiple myeloma cases by clinical and tumor characteristics

We and others have shown increased risk of monoclonal gammopathy of undetermined significance (MGUS) in first-degree relatives of patients with multiple myeloma (MM). Whether familial risk of MGUS differs by the MM proband's age at onset, tumor or clinical characteristics is unknown. MM and smoldering MM (SMM) cases (N = 430) were recruited from the Mayo Clinic in Rochester, Minnesota between 2005-2015. First-degree relatives over age 40 provided serum samples for evaluation of MGUS (N = 1179). Age and sex specific rates of MGUS among first-degree relatives were compared to a population-based sample. Cytogenetic subtypes were classified by Fluorescence in situ hybridization. MGUS was detected in 75 first-degree relatives for an age- and sex- adjusted prevalence of 5.8% (95% CI: 4.5-7.2). Prevalence of MGUS in first-degree relatives was 2.4 fold (95% CI: 1.9-2.9) greater than expected rates. Familial risk did not differ by proband's age at diagnosis, gender, isotype, IgH translocation, or trisomy. This study confirms first-degree relatives of MM cases have a significantly higher risk of MGUS compared to the general population, regardless of age, gender, or tumor characteristics. In selected situations, such as multiple affected first-degree relatives, screening of first-degree relatives of MM cases could be considered for follow-up and prevention strategies.

Defining the Influence of Germline Variation on Metastasis Using Systems Genetics Approaches

Cancer is estimated to be responsible for 8 million deaths worldwide and over half a million deaths every year in the United States. The majority of cancer-related deaths in solid tumors is directly associated with the effects of metastasis. While the influence of germline factors on cancer risk and development has long been recognized, the contribution of hereditary variation to tumor progression and metastasis has only gained acceptance more recently. A variety of approaches have been used to define how hereditary variation influences tumor progression and metastasis. One approach that garnered much early attention was epidemiological studies of cohorts of cancer patients, which demonstrated that specific loci within the human genome are associated with a differential propensity for aggressive tumor development. However, a powerful, and somewhat underutilized approach has been the use of systems genetics approaches in transgenic mouse models of human cancer. Such approaches are typically multifaceted, and involve integration of multiple lines of evidence derived, for example, from genetic and transcriptomic screens of genetically diverse mouse models of cancer, coupled with bioinformatics analysis of human cancer datasets, and functional analysis of candidate genes. These methodologies have allowed for the identification of multiple hereditary metastasis susceptibility genes, with wide-ranging cellular functions including regulation of gene transcription, cell proliferation, and cell-cell adhesion. In this chapter, we review how each of these approaches have facilitated the identification of these hereditary metastasis modifiers, the molecular functions of these metastasis-associated genes, and the implications of these findings upon patient survival.

Validity of self-reported family history of cancer: A systematic literature review on selected cancers

Evidence regarding validity of self-reported family history of cancer (FHC) has been reviewed only for breast, colorectal, prostate, ovarian, endometrial and uterine cancer. We aimed to systematically review studies assessing validity of self-reported family history for the remaining cancer sites. We searched the Medline database for relevant studies published by January 2016. We extracted information on the study design and the positive predictive value (PPV) of self-reported FHC, defined as the proportion of reported cancer diagnoses among relatives that was confirmed by a reference standard (as a measure of over-reporting). We also extracted information on sensitivity of self-reported FHC (as a measure of underreporting). Overall, 21 studies were included that provided information on the PPV of self-reported FHC for relevant cancers and four studies also provided information on sensitivity. The PPV was highest (mostly >70%) for pancreatic, lung, thyroid and urinary system cancers and for leukemia and lymphoma, while it was lowest for stomach and liver cancer. Sensitivity was highest (>70%) for pancreatic cancer, lung cancer, brain cancer, melanoma, leukemia and lymphoma. For several cancers, sample sizes were low and the number of studies limited, particularly regarding sensitivity of self-reported FHC. In conclusion, for some cancers (e.g., pancreatic cancer, lung cancer, leukemia, lymphoma) self-reported FHC can be considered sufficiently valid to be useful, for example, in preventive counseling. For several cancers, it is not sufficiently studied or the pattern is inconsistent. This needs to be taken into account when using self-reported information about FHC in clinical practice or epidemiological research.

Family history of hematologic malignancies and risk of multiple myeloma: differences by race and clinical features

PURPOSE

Multiple myeloma (MM) is the most common hematologic malignancy affecting Blacks in the USA, with standardized incidence rates that are twofold to threefold higher than Whites. The rationale for the disparity is unclear.

METHODS

Using participants enrolled in the Molecular And Genetic Epidemiology study of myeloma (259 MM cases; 461 controls), we examined the risk of MM associated with family history of cancer, differences by race and among cases, defining clinical features. Risk estimates were calculated using odds ratios and corresponding 95% confidence intervals from logistic regression adjusted for confounders.

RESULTS

Overall, MM risk in cases with relatives affected with any hematologic malignancy was significantly elevated compared to controls (OR 1.89, 95% CI 1.25-2.86). Myeloma risk associated with a family history of MM was higher than the risk associated with any hematologic malignancy (OR 3.75, 95% CI 1.75-8.05), and the effect was greater for Blacks (OR 20.9, 95% CI 2.59-168) than Whites (OR 2.04, 95% 0.83-5.04), among cases with early onset (≤60 years; OR 4.58, 95% CI 1.21-17.3) and with increasing numbers of affected relatives (p trend = 0.001). Overall, frequencies of end organ damage differed in cases with relatives affected with any hematologic malignancy and significantly more cases exhibited κ light chain restriction (OR 3.23, 95% CI 1.13-9.26).

CONCLUSIONS

The excess risk of MM observed in Blacks and the variation in clinical features observed in MM patients according to family history of hematologic malignancy may be attributed to a shared germline and environmental susceptibility.

Search for familial clustering of multiple myeloma with any cancer

Multiple myeloma (MM) is a disease of immunoglobulin-producing plasma cells, which reside mainly in the bone marrow. Family members of MM patients are at a risk of MM, but whether other malignancies are in excess in family members is not established and is the aim of this study. MM patients (24 137) were identified from the Swedish Cancer Registry from years 1958 to 2012. Relative risks (RRs) were calculated for MM defined by any cancer diagnosed in first-degree relatives and compared with individuals whose relatives had no cancer. MM was reliably associated with relative's colorectal, breast and prostate cancers, non-thyroid endocrine tumors, leukemia and cancer of unknown primary; in addition, MM was associated with subsites of bone and connective tissue tumors and of non-Hodgkin lymphoma, including lymphoplasmacytic lymphoma/Waldenström macroglobulinema (RR 3.47). MM showed a strong association (RR 1.91) in colorectal cancer families, possibly as part of an unidentified syndrome. All the associations of MM with discordant cancers are novel suggesting that MM shares genetic susceptibility with many cancers. The associations of MM bone and connective tissue tumors were supported by at least two independent results. Whether the results signal bone-related biology shared by MM and these tumors deserves further study.

Familial gastric cancer: guidelines for diagnosis, treatment and periodic surveillance

Hereditary diffuse gastric cancer (HDGC) is a relatively rare disorder, with a mutated CDH1 gene as the only known cause. Carriers of a germline mutation in CDH1 have a lifetime risk of >80% of developing diffuse gastric cancer. As periodic gastric surveillance is of limited value in detecting early stages of HDGC, prophylactic gastrectomy is advised for this patient group. Little is known about other types of familial gastric cancer. The Dutch working group on hereditary gastric cancer has formulated guidelines for various aspects of medical management for families and individuals at high risk of developing gastric cancer, including criteria for referral, classification, diagnostics, and periodic gastric surveillance. These guidelines are not limited to HDGC and are therefore partially complementary to the guidelines on hereditary diffuse gastric cancer of the international gastric cancer linkage consortium (IGCLC 2010). In order to optimize the care and increase the knowledge on hereditary gastric cancer it is important to centralize medical care for these patients. National and international collaboration is warranted to improve the quality of research by increasing the size of study cohorts.

Genetic testing by cancer site: stomach

Gastric cancer is a global public health concern, ranking as the fourth leading cause of cancer mortality, with a 5-year survival of only 20%. Approximately 10% of gastric cancers appear to have a familial predisposition, and about half of these can be attributed to hereditary germline mutations. We review the genetic syndromes and current standards for genetic counseling, testing, and medical management for screening and treatment of gastric cancer. Recently, germline mutations in the E-cadherin/CDH1 gene have been identified in families with an autosomal dominant inherited predisposition to gastric cancer of the diffuse type. The cumulative lifetime risk of developing gastric cancer in CDH1 mutation carriers is up to 80%, and women from these families also have an increased risk for developing lobular breast cancer. Prophylactic gastrectomies are recommended in unaffected CDH1 mutation carriers, because screening endoscopic examinations and blind biopsies have proven inadequate for surveillance. In addition to this syndrome, gastric cancer risk is elevated in Lynch syndrome associated with germline mutations in DNA mismatch repair genes and microsatellite instability, in hereditary breast and ovarian cancer syndrome due to germline BRCA1 and BRCA2 mutations, in familial adenomatous polyposis caused by germline APC mutations, in Li-Fraumeni syndrome due to germline p53 mutations, in Peutz-Jeghers syndrome associated with germline STK11 mutations, and in juvenile polyposis syndrome associated with germline mutations in the SMAD4 and BMPR1A genes. Guidelines for genetic testing, counseling, and management of individuals with hereditary diffuse gastric cancer are suggested. A raised awareness among the physician and genetic counseling communities regarding these syndromes may allow for increased detection and prevention of gastric cancers in these high-risk individuals.

The risks, degree of malignancy and clinical progression of prostate cancer associated with the MDM2 T309G polymorphism: a meta-analysis

To determine the risk, malignant degree and clinical progression of prostate cancer (PCa) associated with mouse double-minute 2 protein (MDM2) T309G variants, a meta-analysis was performed on all eligible published studies. Odds ratios (ORs) with 95% confidence intervals (CIs) were estimated to assess these associations in seven studies that included 5151 cases and 1003 controls. In the overall analysis, the 309G allele was significantly associated with a decreased PCa risk (OR=0.85, 95% CI: 0.74-0.97); this was also the case for the homozygous comparison (OR=0.72, 95% CI: 0.55-0.95) and the dominant genetic model (OR=0.79, 95% CI: 0.65-0.96). The 309G allele was also found to be significantly associated with lower degrees of PCa malignancy (OR=0.85, 95% CI: 0.75-0.96) in the overall analysis, as well as in the heterozygous comparison (OR=0.79, 95% CI: 0.65-0.96), homozygous comparison (OR=0.76, 95% CI: 0.58-0.98) and dominant genetic model (OR=0.81, 95% CI: 0.68-0.96). Furthermore, grouping analysis showed that the 309G allele in Caucasians was significantly correlated with a decreased PCa risk (OR=0.77, 95% CI: 0.61-0.96); this was also the case in the homozygous comparison (OR=0.51, 95% CI: 0.31-0.86). The grouping analysis also showed that the 309G variant in Caucasians was significantly associated with a lower degree of PCa malignancy in all of the genetic models. In addition, we found that the 309G variant in Caucasians was significantly associated with a slower PCa clinical progression in all of the genetic models. In summary, our meta-analysis showed that the MDM2 309G variant was significantly associated with a decreased PCa risk, lower malignant degree and slower clinical progression in Caucasians, but there was no obvious association in the Asian population.

Renal tumors and second primary pancreatic tumors: a relationship with clinical impact?

Background

The occurrence of synchronous or metachronous renal cell carcinoma and pancreatic tumors has been described only in a few cases in the scientific literature. The study of double primary cancers is important because it might provide understanding of a shared genetic basis of different solid tumors and to detect patients at risk for secondary malignancy.

Methods

In a combined analysis of patient registries from University Departments of Urology and Visceral Surgery, 1178 patients with pancreatic tumors and 518 patients with renal cell carcinoma treated between 2001 and 2008 were evaluated,

Results

Overall 16 patients with renal cancer and synchronous (n = 6) or metachronous (n = 10) primary pancreatic tumors were detected. The median survival of all patients was 12.6 months, for the patients with synchronous resections 25.7 months and for the patients with metachronous resections 12.2 months, respectively.

Conclusions

The association between these two etiologies of malignancy demands more detailed epidemiological and molecular investigation. Clinical outcomes would support a resection as a recommended clinically valid option.

Risk factors for multiple myeloma: a hospital-based case-control study in Northwest China

BACKGROUND

The distinctive racial/ethnic and geographic distribution of multiple myeloma (MM) suggests that both family history and environmental factors may contribute to its development.

METHODS

A hospital-based case-control study consisting of 220 confirmed MM cases and 220 individually matched patient controls, by sex, age and hospital was carried out at 5 major hospitals in Northwest China. A questionnaire was used to obtain information on demographics, family history, and the frequency of food items consumed.

RESULTS

Based on multivariate analysis, a significant association between the risk of MM and family history of cancers in first degree relatives was observed (OR=4.03, 95% CI: 2.50-6.52). Fried food, cured/smoked food, black tea, and fish were not significantly associated with the risk of MM. Intake of shallot and garlic (OR=0.60, 95% CI: 0.43-0.85), soy food (OR=0.52, 95% CI: 0.36-0.75) and green tea (OR=0.38, 95% CI: 0.27-0.53) was significantly associated with a reduced risk of MM. In contrast, intake of brined vegetables and pickle was significantly associated with an increased risk (OR=2.03, 95% CI: 1.41-2.93). A more than multiplicative interaction on the decreased risk of MM was found between shallot/garlic and soy food.

CONCLUSION

Our study in Northwest China found an increased risk of MM with a family history of cancer, a diet characterized by low consumption of garlic, green tea and soy foods, and high consumption of pickled vegetables. The effect of green tea in reducing the risk of MM is an interesting new finding which should be further confirmed.

Familial Risks for Diseases of Myoneural Junction and Muscle in Siblings Based on Hospitalizations and Deaths in Sweden

Diseases of the myoneural junction and muscle are disabling and some are life-threatening. Recent successes in the identification of the underlying genetic mechanisms have had profound implication for their diagnostics, treatment and classification. We define familial risks for siblings who were hospitalized for or deceased from diseases of the myoneural junction and muscle. A nationwide database on diseases of the myoneural junction and muscle was constructed by linking the Multigeneration Register on 0- to 69-year-old siblings to the Hospital Discharge Register and the Causes of Death Register from years 1987 to 2001. Standardized risk ratios (SIRs) were calculated for affected sibling pairs by comparing to those whose siblings had no diseases of myoneural junction and muscle. Among a total of 2307 patients, myasthenia gravis, muscular dystrophy and myotonic disorders were commonest diagnoses. The sibling risks for these disease were 22, 190 and 198, respectively, when a sibling was diagnosed with any disease of the myoneural junction and muscle. The concordant SIRs, both siblings presenting the same disease, were 42 for myasthenia gravis, 737 for muscular dystrophy, 2000 for congenital myopathy, 1211 for myotonic disorder, 909 for periodic paralysis and 209 for unspecified myopathy. Only a few discordant sibling pairs were noted. The very high overall SIRs for the diseases of the myoneural junction and muscle imply that the sporadic forms of these diseases are relatively rare and these diseases are overwhelmingly heritable.

Familial monoclonal gammopathy of undetermined significance and multiple myeloma: epidemiology, risk factors, and biological characteristics

Monoclonal gammopathy of undetermined significance (MGUS), a precursor to multiple myeloma (MM), is one of the most common premalignant conditions in the general population. The cause of MGUS is largely unknown. Recent studies show that there is an increased prevalence of MGUS in blood relatives of persons with lymphoproliferative and plasma cell proliferative disorders, suggesting presence of shared underlying genetic influences. In the past few years, additional studies have examined risk factors and biologic characteristics that may contribute to the increased prevalence of MGUS among relatives of probands with MGUS, MM, and other blood malignancies. This article reviews the known epidemiology and risk factors for familial MGUS and myeloma, the risk of lymphoproliferative disorders and other malignancies among blood-relatives of patients with MGUS and MM, and discusses future directions for research.

An epidemiological reappraisal of the familial aggregation of prostate cancer: a meta-analysis

Studies on familial aggregation of cancer may suggest an overall contribution of inherited genes or a shared environment in the development of malignant disease. We performed a meta-analysis on familial clustering of prostate cancer. Out of 74 studies reporting data on familial aggregation of prostate cancer in unselected populations retrieved by a Pubmed search and browsing references, 33 independent studies meeting the inclusion criteria were used in the analysis performed with the random effects model. The pooled rate ratio (RR) for first-degree family history, i.e. affected father or brother, is 2.48 (95% confidence interval: 2.25-2.74). The incidence rate for men who have a brother who got prostate cancer increases 3.14 times (CI:2.37-4.15), and for those with affected father 2.35 times (CI:2.02-2.72). The pooled estimate of RR for two or more affected first-degree family members relative to no history in father and in brother is 4.39 (CI:2.61-7.39). First-degree family history appears to increase the incidence rate of prostate cancer more in men under 65 (RR:2.87, CI:2.21-3.74), than in men aged 65 and older (RR:1.92, CI:1.49-2.47), p for interaction = 0.002. The attributable fraction among those having an affected first-degree relative equals to 59.7% (CI:55.6-63.5%) for men at all ages, 65.2% (CI:57.7-71.4%) for men younger than 65 and 47.9% (CI:37.1-56.8%) for men aged 65 or older. For those with a family history in 2 or more first-degree family members 77.2% (CI:65.4-85.0%) of prostate cancer incidence can be attributed to the familial clustering. Our combined estimates show strong familial clustering and a significant effect-modification by age meaning that familial aggregation was associated with earlier disease onset (before age 65).

MiR-886-3p regulates cell proliferation and migration, and is dysregulated in familial non-medullary thyroid cancer

Background

The molecular basis and characteristics of familial non-medullary thyroid cancer are poorly understood. In this study, we performed microRNA (miRNA) profiling of familial and sporadic papillary thyroid cancer tumor samples.

Methodology/Principal Findings

Genome wide miRNA profiling of sporadic and familial papillary thyroid cancer was performed. Differentially expressed miRNAs were validated by quantitative RT-PCR. Ectopic expression of miR-886-3p in thyroid cancer lines was performed to identify pathways targeted by the miRNA, as well as, to determine its effect on tumor cell biology. We found four differentially expressed miRNAs between familial and sporadic papillary thyroid cancer tumor samples. MiR-886-3p and miR-20a were validated to be differentially expressed by 3- and 4-fold, respectively. Pathway analysis of genome-wide expression data on cells overexpressing miR-886-3p and target prediction analysis showed genes involved in DNA replication and focal adhesion pathways were regulated by miR-886-3p. Overexpression of miR-886-3p in thyroid cancer cell lines significantly inhibited cellular proliferation, the number and size of spheroids and cellular migration. Additionally, overexpression of miR-886-3p increased the number of cells in S phase.

Conclusions/Significance

Our findings for the first time suggest that miR-886-3p plays an important role in thyroid cancer tumor cell biology and regulates genes involved in DNA replication and focal adhesion. Thus, miR-886-3p may play a role in the initiation and or progression of papillary thyroid cancer.

Testicular germ cell tumours: predisposition genes and the male germ cell niche

Testicular germ cell tumours (TGCTs) of adults and adolescents are putatively derived from primordial germ cells or gonocytes. Recently reported genome-wide association studies implicate six gene loci that predispose to TGCT development. Remarkably, the functions of proteins encoded by genes within these regions bridge our understanding between the pathways involved in primordial germ cell physiology, male germ cell development and the molecular pathology of TGCTs. Furthermore, this improved understanding of the mechanisms underlying TGCT development and dissemination has clinical relevance for the management of patients with these tumours.

Gastric adenocarcinoma in a 13-year-old boy: a diagnosis not often seen in this age group

Gastric adenocarcinoma is not uncommon in the adult population, but in the pediatric population it is an extremely rare entity. A 13-year-old boy was referred to a pediatric oncology unit for evaluation of a tumor in the upper abdomen. Further investigation revealed an advanced stage gastric carcinoma with metastases suggestive for a hereditary cause. Awareness for uncommon diagnoses is a key issue in regard of accurate treatment and overall prognosis.

Common single nucleotide polymorphisms in immunoregulatory genes and multiple myeloma risk among women in Connecticut

In light of the relationship between immune system dysregulation and multiple myeloma (MM) risk, we investigated whether genetic variation in 92 immune function genes among 77 gene regions are associated with MM susceptibility in a population-based case-control study (108 cases and 482 controls) conducted among Caucasian women in Connecticut. Tagging single-nucleotide polymorphisms (SNPs; N = 870) were selected using a pairwise linkage-disequilibrium based algorithm. Odds ratios (ORs) and 95% confidence intervals (CIs) for SNP genotypes were estimated using unconditional logistic regression. Tests of association for gene regions were conducted using the minP test. We applied the false discovery rate (FDR) method to the minP test results as a means of controlling for multiple comparisons. The CD4 gene region located on 12p13-q13 (minP = 0.0009), had an FDR value <0.1. In this region, a total of six tag SNPs in two genes (CD4 and LAG3) were significantly associated with MM risk (P(trend)<0.05), with the strongest association observed for the CD4 variant rs11064392 (OR(AG/GG) = 2.53, 95% CI = 1.59-4.02). Our findings suggest that genetic variation in CD4 may influence susceptibility to MM. Additional studies are needed to replicate these findings and, more generally, to explore the manner in which genes and receptors may influence the pathogenesis of this poorly understood malignancy.

Familial association of inflammatory bowel diseases with other autoimmune and related diseases

OBJECTIVES

Familial risk estimates are useful for genetic counseling, etiological understanding, and design of gene identification studies. We wanted to estimate the associations of ulcerative colitis (UC) and Crohn's disease (CD) with 32 autoimmune and related diseases among parents and offspring, singleton siblings, twins, and spouses.

METHODS

The Multigeneration Register in Sweden provides reliable access to information on families among 11.5 million individuals throughout the last century. The diseases in individual family members were obtained through linkage to the Hospital Discharge Register. Standardized incidence ratios (SIRs) and 95% confidence intervals were calculated as relative risks for UC/CD in family members of patients diagnosed with any of the 34 diseases compared with those lacking affected family members through years 1964-2004.

RESULTS

Among a total of 441,642 patients diagnosed with autoimmune and related conditions, 25,846 were diagnosed with UC and 18,885 with CD. Familial cases amounted to 5.4% of all UC patients and 6.5% of CD patients. SIR for UC was 3.9 (95% confidence interval 3.5-4.3) in offspring of affected parents, 4.6 (3.0-7.4) in siblings, 10.4 (6.5-15.8) in families of affected parents and siblings, and 6.3 (1.9-17.7) for monozygotic twins. The respective SIRs for CD were 6.0 (5.4-6.7), 6.3 (4.1-9.8), 34.0 (24.9-45.3), and 23.4 (10.1-51.1). All discordant associations, i.e., those between CD and other diseases, were also found for UC, including ankylosing spondylitis, asthma, polymyalgia rheumatica, psoriasis, and sarcoidosis. For UC, six additional associations were observed. No correlations between specific diseases were found among spouses, but between UC or CD and any disease it was 1.1 (1.0-1.1).

CONCLUSIONS

The concordant familial risks for UC and CD were lower than those commonly cited. Both diseases are associated with several autoimmune and related diseases, suggesting genetic sharing.

Understanding the validity of self-reported positive family history of lymphoma in extended families to facilitate genetic epidemiology and clinical practice

The validity of self-reported information about familial Hodgkin lymphoma (HL), important for epidemiologic research and clinical practice, is undetermined. We attempted to validate 55 familial lymphomas previously reported by 48 subjects in a population-based case-control study of HL in women. Of 44 diagnoses (80%) reported by 40 (83%) recontacted subjects, we obtained medical documentation for 36 (82%). Twenty-nine (81%) were validated as lymphoma, with accuracy better for first-degree relatives and subjects with larger nuclear families and other family illness. Fourteen reports of familial HL were validated as lymphoma for 13 (93%) and as HL for nine (64%). Fifteen reports of familial NHL were validated as lymphoma for 10 (67%) and as NHL for 10 (67%). Thus, familial HL reported by HL patients and controls is highly likely to be lymphoma even in extended family members but less likely to be HL per se. Validity may vary with the subject's family size and medical history.

Factors associated with testicular self-examination among unaffected men from multiple-case testicular cancer families

Background

The lifetime testicular cancer (TC) risk in the general population is relatively low (~1 in 250), but men with a family history of TC are at 4 to 9 times greater risk than those without. Some health and professional organizations recommend consideration of testicular self-examination (TSE) for certain high-risk groups (e.g. men with a family history of TC). Yet little is known about factors associated with TSE behaviors in this at-risk group.

Methods

We collected information on this subject during an on-going NCI multidisciplinary, etiologically-focused, cross-sectional Familial Testicular Cancer (FTC) study. We present the first report specifically targeting TSE behaviors among first- and second-degree relatives (n = 99) of affected men from families with ≥ 2 TC cases. Demographic, medical, knowledge, health belief, and psychological factors consistent with the Health Belief Model (HBM) were evaluated as variables related to TSE behavior, using chi-square tests of association for categorical variables, and t-tests for continuous variables.

Results

For men in our sample, 46% (n = 46) reported performing TSE regularly and 51% (n = 50) reported not regularly performing TSE. Factors associated (p < .05) with regularly performing TSE in multivariate analysis were physician recommendation and testicular cancer worry. This is the first study to examine TSE in unaffected men from FTC families.

Conclusion

The findings suggest that, even in this high-risk setting, TSE practices are sub-optimal. Our data provide a basis for further exploring psychosocial issues that are specific to men with a family history of TC, and formulating intervention strategies aimed at improving adherence to TSE guidelines.

Genetic variation in cell cycle and apoptosis related genes and multiple myeloma risk

Genetic variation may be an important risk factor for multiple myeloma. A hallmark of tumor formation and growth is cell cycle dysregulation and apoptosis avoidance. We previously reported the association of genetic variation in caspase genes, the apoptotic-regulating family, and multiple myeloma risk. To further examine if genetic variation in key cell cycle and apoptosis genes alters multiple myeloma risk, we genotyped 276 tag SNPs in 27 gene regions in a population-based case-control study of non-Hispanic Caucasian women (108 cases; 482 controls) in Connecticut. Logistic regression assessed the effect of each SNP on multiple myeloma risk and the minP test assessed the association at the gene region level. Three gene regions were significantly associated with risk of multiple myeloma (BAX minP=0.018, CASP9 minP=0.025, and RIPK1 minP=0.037). Further explorations identified the most significant variant of BAX, RIPK1, and CASP9 to be rs1042265, rs9391981, and rs751643, respectively. The A variant at rs1042265 (OR(GA+AA)=0.40, 95% CI=0.21-0.78) and the C variant at rs9391981 (OR(GC+CC)=0.32, 95% CI=0.12-0.81) were associated with a decreased risk of multiple myeloma. The G variant at rs7516435 was associated with an increased risk of multiple myeloma (OR(AG)=1.48, 95% CI=0.94-2.32; OR(GG)=2.59, 95% CI=1.30-5.15; p(trend)=0.005). Haplotype analyses supported the SNP findings. These findings suggest that genetic variation in cell cycle and apoptosis genes may play a key role in multiple myeloma and warrant further investigation through replication studies.

Genetic and environmental risk indicators in canine non-Hodgkin's lymphomas: breed associations and geographic distribution of 608 cases diagnosed throughout France over 1 year

BACKGROUND

The etiology of non-Hodgkin's lymphomas (NHL) is multifactorial. Environmental and genetic factors are frequently incriminated both in humans and dogs.

OBJECTIVES

Our purpose was to study the geographic distribution of canine NHL (CNHL) in France and to evaluate genetic and environmental influences.

ANIMALS

Six hundred and eight cases of CNHL, diagnosed throughout France over 1 year, were collected from 7 Veterinary Histopathologic Laboratories.

METHODS

Retrospective study. Breeds affected by lymphomas were compared with the national population and associations between breed and immunophenotype were studied. The distribution of CNHL and canine T-cell NHL per 100,000 dogs per department was compared with the distribution of waste incinerators, polluted sites, and radioactive waste.

RESULTS

The breeds significantly overrepresented among lymphoma cases were Boxer, Setter, and Cocker Spaniel (P < .001). There was a significant association between Boxer and T-cell NHL (P < .001), and between German Shepherd and Rottweiler and B-cell NHL (P < .01). The geographic distribution of CNHL and canine T-cell NHL indicated significant heterogeneity. Significant association between distributions of CNHL and waste incinerators (rho= 0.25, P < .05), polluted sites (rho= 0.36, P < .001), and radioactive waste (rho= 0.51, P < .001) was found.

CONCLUSIONS AND CLINICAL IMPORTANCE

Influence of genetics in the development of CNHL was supported by the existence of an association between breed and immunophenotype. Waste incinerators, polluted sites, and radioactive waste could just be considered as risk indicators of CNHL, but not as risk factors. Case-control studies around critical sites are necessary to confirm the implication of those environmental factors in the development of CNHL.

A compendium of familial relative risks of cancer among first degree relatives: a population-based study

Familial clustering of cancer is expected to occur at practically all anatomical sites. However, few studies have had sufficient size to investigate different sites simultaneously and with adjustment for confounders. We evaluated familial clustering in the Netherlands Cohort Study in which 120,852 men and women, aged 55-69 years in 1986 were followed up for 13.3 years. 14,025 Probands, 6,629 parents and 4,271 siblings were diagnosed with cancer. Relative Risks (RR) of cancer in first degree family members were calculated by using multivariable Cox regression analyses. We also calculated false-positive reporting probabilities. Significant concordant familial clustering was observed for stomach (RR(father) = 1.89, RR(parent) = 1.66, RR(sister) = 3.33, RR(sibling) = 2.38, RR(1st degree) = 1.69), colon/rectum (RR(father) = 1.82, RR(mother) = 1.83, RR(parent) = 1.88, RR(1st degree) = 1.56), lung (RR(brother) = 1.50) and breast cancer (RR(mother) = 1.65, RR(sister) = 1.72, RR(1st degree) = 1.72) with low false-positive reporting probabilities. Significant discordant familial clustering has been observed for combinations of pancreas-colon/rectum (RR(mother) = 2.42, RR(parent) = 1.89, RR(1st degree) = 1.73), larynx-lung (RR(father) = 3.35, RR(parent) = 2.84, RR(1st degree) = 2.30), lung-oesophagus (RR(sibling) = 3.49), breast-bladder (RR(father) = 2.79, RR(parent) = 2.61), endometrium-stomach (RR(mother) = 2.32), ovarium-oesophagus (RR(1stdegree) = 4.19), prostate-colon/rectum (RR(parent) = 1.46) and bladder-larynx/pharynx (RR(father) = 2.49) cancer, although false-positive reporting probabilities were higher for these associations. Familial clustering of cancer occurs at most sites but is generally modest. Some observed discordant familial clustering is surprising but should be interpreted with caution as their prior probability is low.

Age-specific familial risks of depression: a nation-wide epidemiological study from Sweden

OBJECTIVE

Familial risks of depression have been assessed in small case-control studies, usually based on reported, but not medically verified, depressions in family members; thus the degree of familial clustering of these diseases remains to be established.

METHODS

The Multigeneration Register, in which all men and women born in Sweden from 1932 onward are registered together with their parents, was linked to hospital admission data. Standardized incidence ratios (SIRs) were calculated as the ratio of the observed to the expected number of cases in men and women with mothers or fathers affected by depression, compared with men and women whose mothers or fathers were not affected by depression.

RESULTS

A total of respectively 60,477 and 79,969 depressions were recorded in offspring and parents. In 6.44% of all families, an offspring and a parent were affected, giving a population-attributable proportion of 4.04% and a familial SIR of 2.68. The parental transmission of depression was similar for both men and women (2.72 and 2.66).

CONCLUSIONS

This study has provided the first data on age-specific familial clustering of depressions, based on medically confirmed records. The risks were so high that hereditary factors were considered to be likely to contribute to depression, possibly modified by environmental factors. Age-specific risk tables would be helpful for clinical counseling.

Age of onset in familial cancer

BACKGROUND

Reliable estimates on the age of onset between familial and sporadic cancers are important for etiological understanding and clinical practice. Specific studies on the age of onset of familial cancer compared with sporadic cancer are less common than studies on familial risks and these are almost lacking for rare cancers.

MATERIALS AND METHODS

The Swedish Family-Cancer Database was used to estimate cumulative risks of all common cancer types according to family history with a stratified Cox model based on Tsiatis' method. We calculated the age at which the cumulative risk of cancer reached 0.1% and 0.5%.

RESULTS

The age to reach a cumulative risk of 0.1% was significantly lower among individuals with a parent or a sibling affected for any of the investigated cancer sites. The age differences ranged from 2.6 years (sons of prostate cancer patients) to 16.3 years (brothers of urinary bladder cancer patients). A cumulative risk of 0.5% was also reached earlier for individuals with a family history, especially for individuals with a parent and a sibling affected.

CONCLUSIONS

Cancers in individuals with a family history occur earlier than in sporadic patients. The derived estimates may be useful for clinical counseling and screening recommendations.

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.

Breast cancer onset in twins and women with bilateral disease

PURPOSE

Little is known of the onset of breast cancer in high-risk populations. We investigated the risk of breast cancer in twin sisters and in the contralateral breast taking family history into consideration.

PATIENTS AND METHODS

We analyzed a Scandinavian population-based cohort of 2,499 female twin pairs, in which at least one had a diagnosis of breast cancer and estimated the risk of breast cancer in the sister. Using a total of 11 million individuals in Sweden with complete family links, we identified 93,448 women with breast cancer and estimated the risk of a bilateral breast cancer.

RESULTS

The incidence of breast cancer in twin sisters of breast cancer patients was 0.64% per year and 0.42% per year in mono- and dizygotic twin sisters, respectively. In comparison, the risk of familial (affected first-degree relative) and nonfamilial bilateral breast cancer was 1.03% per year and 0.68% per year, respectively. Contrary to the risk of unilateral disease, the risk of cancer in the nonaffected twin and the opposite breast was not affected by age or time since first event. The relative risk of familial bilateral cancer was 52% higher (incidence rate ratio [IRR] = 1.52; 95% CI, 1.42 to 1.64) and the relative risk in the dizygotic twin sister was 25% lower (IRR = 0.75; 95% CI, 0.61 to 0.91) compared with the risk of nonfamilial bilateral cancer.

CONCLUSION

The elevated risk of breast cancer in high-risk groups is little affected by age and time since diagnosis. Our findings suggest that susceptible groups of women might have already aggregated genetic prerequisites for breast cancer.

How common is familial cancer?

BACKGROUND

Family history of a disease may point to its heritable or environmental etiology. It can be described by the proportion of the familial disease, i.e. same disease in two or more family members. A family history always needs to be specified as to the number of generations covered and their ages.

PATIENTS AND METHODS

Proportions of site-specific familial cancers (familial proportions) were calculated using the Swedish Family-Cancer Database, the largest dataset of its kind in the world, with cancers from the Swedish Cancer Registry. Familial proportions refer to the offspring population up to age 72 years when their parents or siblings were diagnosed with a concordant (same) cancer.

RESULTS

A total of 34 cancer sites and 205 638 cases were covered. Prostate cancer showed the highest familial proportion of 20.15%, followed by breast (13.58%) and colorectal (12.80%) cancers. Salivary gland cancers showed the lowest familial proportion of 0.15%, but bone, laryngeal, anal, connective tissue and other genital cancers also remained <1%. The familial proportion depended on the prevalence of the particular cancer and on its familial risk.

CONCLUSIONS

The derived familial proportions can justifiably be used in statements 'X% of the patients had a family history of the cancer'.

Risks of subarachnoid hemorrhage in siblings: a nationwide epidemiological study from Sweden

This nationwide study aimed to enhance available data by determining sibling risks of subarachnoid hemorrhage in a total population. The MigMed database at the Karolinska Institute, Stockholm, was used to identify all cases of subarachnoid hemorrhage diagnosed in Sweden between 1987 and 2001. Incidence ratios standardized for age, region, and socioeconomic status (SIRs) were calculated for persons with at least 1 sibling with subarachnoid hemorrhage. The reference group consisted of persons whose siblings had no subarachnoid hemorrhage. A total of 90 affected siblings were identified; their SIR of subarachnoid hemorrhage was 2.75. The risk decreased with increasing age in both men and women. Within the limits of the sample size, no sex differences could be observed. The relatively high sibling risks are likely to be due to heritable causes and shared environmental factors. Genetic causes possibly weigh more in early- than late-onset cases. This study shows the feasibility of carrying out nationwide family studies on subarachnoid hemorrhage.

Mortality from cancer and other causes in parents of children with cancer: a population-based study in Piedmont, Italy

This population-based study (the largest on this issue conducted in Southern Europe) has examined mortality among the parents of 2622 children diagnosed with cancer in Piedmont during 1967-1994. Parents were followed up from the date of the index child's birth until the end of 2000, yielding a total of 118 090.7 person-years of observation. Standardized mortality ratios (SMRs) were estimated using mortality rates for the whole population of Piedmont as the reference. Among mothers, total mortality was similar to that expected [SMR 1.02, 95% confidence interval (CI) 0.85-1.23, 117 cases]. A reduced risk of mortality was seen in fathers (SMR 0.91, 95% CI 0.81-1.02, 293 cases); this was largely due to causes other than cancer and the reduction in risk disappeared after the index child's death (SMR 0.98, 95% CI 0.84-1.15, 168 cases). Deaths from cancers of the lymphohaematopoietic system were in excess among mothers (SMR=2.13, 95% CI 1.02-3.92, 10 cases) and breast cancer deaths were in excess specifically among mothers of leukaemic children (SMR 2.32, 95% CI 1.16-4.14, 11 cases). Three mothers dying with breast cancer had index children who had been diagnosed with a bone sarcoma. Parental cancer of the respiratory tract was significantly associated with both tumours of the central nervous system and Hodgkin's lymphoma in the index child. The excess risks identified here may be due to genetic factors or due to parental psychological stress consequent to cancer in a child that may lead to increased mortality either through the direct effects of stress or through consequent changes in lifestyle.

Familial concordance in cancer survival: a Swedish population-based study

BACKGROUND

Nowadays, the fact that cancers can aggregate in families is generally accepted. The aim of this study was to complete a comprehensive analysis of cancer-survival concordance in parents and their children diagnosed with the same cancer.

METHODS

We used a population-based Swedish family database, that included about three million families and data for more than a million individuals with cancer. We analysed survival in children in relation to parental survival by use of the Kaplan-Meier method. We then modelled the risk in children in relation to parental survival by use of two multivariate proportional hazard (Cox) models adjusting for possible confounders of survival.

FINDINGS

In our univariate Kaplan-Meier analysis, children with the same cancer as their parent and whose parent had died within 10 years of diagnosis showed significantly worse survival for breast (log rank p=0.01), colorectal (p=0.04), and prostate cancer (p=0.05) than those whose parents were alive at 10 years from diagnosis. By use of Cox modelling, we noted an increased hazard ratio for death from cancer in children with poor parental survival compared with those with good parental survival for colorectal cancer (hazard ratio [HR] 1.44 [95% CI 1.01-2.01]), lung cancer (1.39 [1.00-1.94]), breast cancer (1.75 [1.13-2.71]), ovarian cancer (2.23 [0.78-6.34]), and prostate cancer (2.07 [1.13-3.79]). All hazard-ratio estimates, except for ovarian cancer, were significant, with significant trends of increasing risk of death in children by degree of worsening survival outcome in parents defined in quartiles of survival (ie, good [best quartile], expected [middle two quartiles], or poor [worst quartile]).

INTERPRETATION

Our findings suggest that cancer-specific survival in parents predicts survival from the same cancer in their children. Consequently, data on survival in a parent might have the potential to guide treatment decisions and genetic counselling. Finally, molecular studies to highlight the genetic determinants of cancer survival are now warranted.

Familial risks for asthma among twins and other siblings based on hospitalizations in Sweden

BACKGROUND

Asthma is a common disabling condition, with known environmental and familial risk factors and with their assumed interactions. We wanted to carry out a family study on asthma to address gene-environment interactions at a population level.

METHODS

We conducted a nation-wide study on familial risks for asthma. An asthma database was constructed by linking the Multigeneration Register on 0-72-year-old subjects to the Hospital Discharge Register for diagnosed asthma cases in Sweden from years 1987 to 2004. Standardized incidence ratios (SIRs) were calculated for affected singleton siblings, twins and spouses by comparing with those whose siblings or spouses had no asthma.

RESULTS

A total of 67 370 hospitalized cases and 5638 affected siblings were identified with a familial SIR of 3.70, which was independent of sex, diagnostic age and age differences between the siblings. The SIR for different-sex twins was 5.17 and for same-sex twins it was 13.38. There was a low correlation between spouses for asthma.

CONCLUSIONS

Asthma shows a higher familial risk than many common diseases. The higher difference in familial excess risk between singleton siblings and different-sex twins provides strong genetic epidemiological evidence for gene-environment interactions in asthma. The concept of gene-environment interactions needs to be accommodated in future aetiological studies on asthma. Data on environmental factors and family history are important for clinical risk estimation.

The surgeon's role in cancer prevention. The model in colorectal carcinoma

Cancer Prevention is an emerging field, capturing the old traditional concept of anticipating the development of a major disease and preventing its full impact by early detection, treatment, or aborting the tumorigenic process by a "molecular vaccine" and alleviating the full impact of the disease. Surgeons are important clinician scientists who can carry this discipline forward and develop its full potential in the clinics and in the community. Advances in molecular biology, genetics, and other technologies have permitted seminal understanding of the carcinogenic pathways and identification of targets and intermediate end points in neoplasia. In this review, we will see that we have the means of preventing significant numbers of colorectal carcinomas (CRC).

Breast cancer in first-degree relatives and risk of lung cancer: assessment of the existence of gene sex interactions

BACKGROUND

Previous studies have shown the sex differences in lung cancer and the associations between estrogen-related genes and non-small cell lung cancer. In the present study, we assumed the existence of shared candidate genes that are common in lung and breast cancers, and examined whether women with a family history of breast cancer are at increased risk of lung cancer compared with men, especially adenocarcinoma, in a case-only study.

METHODS

This case-only study was conducted based on the Lung Cancer Database Project at the National Cancer Center Hospital East. A total of 1566 patients with newly diagnosed primary lung cancer were consecutively recruited between 1999 and 2003. Information on their family history of cancer and smoking habit was obtained from a self-administered questionnaire. To assess an interactions between two factors, odds ratios for interaction (ORis) and 95% confidence intervals (CIs) were calculated by case-only contingency table.

RESULTS

A statistically significant ORi was observed between a family history of breast cancer in first-degree relatives (parent and siblings, not including children) and the sex of a patient (ORi: 2.22, 95% CI: 1.02-4.81). A stratified analysis by histologic subtypes showed a statistically significant ORi only for adenocarcinoma (ORi: 3.27, 95% CI: 1.19-8.98). No other family history of cancer, such as stomach, colon and lung cancer, showed a statistically significant ORi.

CONCLUSION

This study suggests the possibility of gene-sex interaction in lung cancer.

Familial testicular cancer: interest in genetic testing among high-risk family members

PURPOSE

This study is part of an ongoing National Cancer Institute multidisciplinary, etiologically-focused, cross-sectional study of Familial Testicular Cancer (FTC). The current report targets interest in clinical genetic testing for susceptibility to FTC.

METHODS

Demographics, knowledge, health beliefs, and psychological and social factors were evaluated as covariates related to interest in genetic testing.

RESULTS

The majority (66%) of 229 participants (64 affected men, 66 unaffected men, and 99 women) from 47 multiple-case FTC families expressed interest in having a genetic test within 6 months, should such a test become available. Interest was similar among the three subgroups mentioned above. Worries about insurance discrimination based on genetic test results were associated with a significantly lower interest in testing. Alternatively, participants were more likely to be interested in genetic testing if they were younger and had higher levels of family support, a physician's recommendation supporting testing, cancer distress, and a need for information to inform the health care of their children.

CONCLUSIONS

This study reveals social and relationship factors that FTC survivors and their relatives considered important when contemplating the use of new genetic technologies. This is the first study describing hypothetical interest in genetic testing for familial testicular cancer.

Factores etiológicos del cáncer de pulmón: fumador activo, fumador pasivo, carcinógenos medioambientales y factores genéticos

Every year, in Spain 18,000 new cases of lung cancer (LC) are diagnosed. Approximately, 80-90% LC in men and women are directly attributable to tobacco abuse. Cigarette smoke contains over 300 chemicals, 40 of which are known to be potent carcinogens. In the last decade, as in Spain, prevalence of smoking in women has generally increased in the European Union. LC risk can be substantially reduced after smoking cessation, yet never reaches baseline. On the other hand, environmental tobacco smoke exposure (passive smoking) in nonsmokers appears to have a significantly increased risk of LC. An updated of etiology factors of LC, risk related to duration as well as intensity of smoking, relationship between environmental tobacco smoke exposure and LC risk, genetic predisposition and a variety of occupational and environmental exposures implicated as potential risk factors for the development of LC will be reviewed here.