Longer Interval Between First Colonoscopy With Negative Findings for Colorectal Cancer and Repeat Colonoscopy

Importance

For individuals without a family history of colorectal cancer (CRC), colonoscopy screening every 10 years is recommended to reduce CRC incidence and mortality. However, debate exists about whether and for how long this 10-year interval could be safely expanded.

Objective

To assess how many years after a first colonoscopy with findings negative for CRC a second colonoscopy can be performed.

Design, Setting, and Participants

This cohort study leveraged Swedish nationwide register-based data to examine CRC diagnoses and CRC-specific mortality among individuals without a family history of CRC. The exposed group included individuals who had a first colonoscopy with findings negative for CRC at age 45 to 69 years between 1990 and 2016. The control group included individuals matched by sex, birth year, and baseline age (ie, the age of their matched exposed individual when the exposed individual's first colonoscopy with findings negative for CRC was performed). Individuals in the control group either did not have a colonoscopy during the follow-up or underwent colonoscopy that resulted in a CRC diagnosis. Up to 18 controls were matched with each exposed individual. Individuals were followed up from 1990 to 2018, and data were analyzed from November 2022 to November 2023.

Exposure

A first colonoscopy with findings negative for CRC, defined as a first colonoscopy without a diagnosis of colorectal polyp, adenoma, carcinoma in situ, or CRC before or within 6 months after screening.

Main Outcomes and Measures

The primary outcomes were CRC diagnosis and CRC-specific death. The 10-year standardized incidence ratio and standardized mortality ratio were calculated to compare risks of CRC and CRC-specific death in the exposed and control groups based on different follow-up screening intervals.

Results

The sample included 110 074 individuals (65 147 females [59.2%]) in the exposed group and 1 981 332 (1 172 646 females [59.2%]) in the control group. The median (IQR) age for individuals in both groups was 59 (52-64) years. During up to 29 years of follow-up of individuals with a first colonoscopy with findings negative for CRC, 484 incident CRCs and 112 CRC-specific deaths occurred. After a first colonoscopy with findings negative for CRC, the risks of CRC and CRC-specific death in the exposed group were significantly lower than those in their matched controls for 15 years. At 15 years after a first colonoscopy with findings negative for CRC, the 10-year standardized incidence ratio was 0.72 (95% CI, 0.54-0.94) and the 10-year standardized mortality ratio was 0.55 (95% CI, 0.29-0.94). In other words, the 10-year cumulative risk of CRC in year 15 in the exposed group was 72% that of the 10-year cumulative risk of CRC in the control group. Extending the colonoscopy screening interval from 10 to 15 years in individuals with a first colonoscopy with findings negative for CRC could miss the early detection of only 2 CRC cases and the prevention of 1 CRC-specific death per 1000 individuals, while potentially avoiding 1000 colonoscopies.

Conclusions and Relevance

This cohort study found that for the population without a family history of CRC, the 10-year interval between colonoscopy screenings for individuals with a first colonoscopy with findings negative for CRC could potentially be extended to 15 years. A longer interval between colonoscopy screenings could be beneficial in avoiding unnecessary invasive examinations.

The effect of Mediterranean diet on inflammatory biomarkers and components of metabolic syndrome in adolescent girls

BACKGROUND

The prevalence of obesity and metabolic syndrome (MetS) during childhood and adolescence is rising significantly worldwide. Previous studies have shown that following a healthy dietary pattern, like the Mediterranean diet (MD), might be an efficacious approach for the prevention and management of MetS during childhood. In the present study, we aimed to examine the effect of MD on inflammatory markers and components of MetS among adolescent girls with MetS.

METHODS

This randomized controlled clinical trial was conducted on 70 girl adolescents with metabolic syndrome. Patients in the intervention group followed a prescribed MD, while participants in the control group received dietary advice according to the food pyramid. The length of intervention was 12 weeks. Participants' dietary intakes were evaluated using three 1-day food records throughout the study. Anthropometric measures, inflammatory markers, systolic and diastolic blood pressure, and hematological factors were assessed at the baseline and end of the trial. An intention-to-treat approach was taken into account for the statistical analysis.

RESULTS

After 12 weeks, participants in the intervention group had lower weight (Ptime*group ≤ 0/001), body mass index (BMI) (Ptime*group ≤ 0/001), and waist circumference (WC) (Ptime*group ≤ 0/001) compared with those in the control group. In addition, MD resulted in a significantly reduced systolic blood pressure compared to the those in the control group (Ptime*group ≤ 0/001). In terms of metabolic variables, MD led to a significant decrease in fasting blood glucose (FBS) (Ptime*group ≤ 0/001), triglycerides (TG) (Ptime*group ≤ 0/001), low-density lipoprotein (LDL) (Ptime*group ≤ 0/001), homeostatic model assessment of insulin resistance (HOMA-IR) (Ptime*group = 0/02) and a meaningful increase in serum levels of high-density lipoprotein (HDL) (Ptime*group ≤ 0/001). In addition, adherence to the MD resulted in a significant reduction in serum levels of inflammatory markers including Interleukin 6 (IL-6) (Ptime*group = 0/02) and high-sensitivity C-reactive protein (hs-CRP) (Ptime*group = 0/02). However, no significant effect was seen on serum levels of tumor necrosis factor α (TNF-α) (Ptime*group = 0/43).

CONCLUSION

Overall, the findings of the present study revealed that consumption of MD for 12 weeks resulted in a favorable effect on anthropometric measures, components of MetS, as well as on some inflammatory biomarkers.

Gallstones, cholecystectomy and kidney cancer: observational and Mendelian randomisation results based on large cohorts

BACKGROUND AND AIMS

Gallstones (cholelithiasis) constitute a major health burden with high costs related to surgical removal of the gallbladder (cholecystectomy), generally indicated for symptomatic gallstones. The association between gallstones, cholecystectomy and kidney cancer is controversial. We comprehensively investigated this association, considering age at cholecystectomy and time from cholecystectomy to kidney cancer diagnosis, and assessing the causal effect of gallstones on kidney cancer risk by Mendelian randomisation (MR).

METHODS

We compared the risk of kidney cancer in cholecystectomised and non-cholecystectomised individuals (16.6 million in total) from the Swedish nationwide cancer, census, patient and death registries using hazard ratios (HRs). For two-sample and multivariable MR, we used summary statistics based on 408,567 UK Biobank participants.

RESULTS

During a median follow-up of 13 years, 2,627 of 627,870 cholecystectomised Swedish patients developed kidney cancer (HR=1.17, 95% CI 1.12-1.22). Kidney cancer risk was particularly increased in the first 6 months after cholecystectomy (HR=3.79, 95% CI 3.18-4.52) and in patients cholecystectomised before age 40 (HR=1.55, 95% CI 1.39-1.72). MR results based on 18.417 gallstone and 1,788 kidney cancer patients from the UK revealed a causal effect of gallstones on kidney cancer risk (9.6% risk increase per doubling in gallstone prevalence, 95% CI 1.2%-18.8%).

CONCLUSIONS

Both observational and causal MR estimates based on large prospective cohorts support an increased risk of kidney cancer in gallstone patients. Our findings provide solid evidence for the compelling need to diagnostically rule out kidney cancer before and during gallbladder removal, to prioritise kidney cancer screening in patients undergoing cholecystectomy in their 30s, and to investigate the underlying mechanisms linking gallstones and kidney cancer in future studies.

Race and Ethnicity-Adjusted Age Recommendation for Initiating Breast Cancer Screening

Importance

Breast cancer (BC) is the second leading cause of cancer death in women, and there is a substantial disparity in BC mortality by race, especially for early-onset BC in Black women. Many guidelines recommend starting BC screening from age 50 years; however, the current one-size-fits-all policy to start screening all women from a certain age may not be fair, equitable, or optimal.

Objective

To provide race and ethnicity-adapted starting ages of BC screening based on data on current racial and ethnic disparities in BC mortality.

Design, Setting, and Participants

This nationwide population-based cross-sectional study was conducted using data on BC mortality in female patients in the US who died of BC in 2011 to 2020.

Exposures

Proxy-reported race and ethnicity information was used. The risk-adapted starting age of BC screening by race and ethnicity was measured based on 10-year cumulative risk of BC-specific death. Age-specific 10-year cumulative risk was calculated based on age group-specific mortality data without modeling or adjustment.

Main Outcomes and Measures

Disease-specific mortality due to invasive BC in female patients.

Results

There were BC-specific deaths among 415 277 female patients (1880 American Indian or Alaska Native [0.5%], 12 086 Asian or Pacific Islander [2.9%], 62 695 Black [15.1%], 28 747 Hispanic [6.9%], and 309 869 White [74.6%]; 115 214 patients died before age 60 years [27.7%]) of any age in the US in 2011 to 2020. BC mortality per 100 000 person-years for ages 40 to 49 years was 27 deaths in Black females, 15 deaths in White females, and 11 deaths in American Indian or Alaska Native, Hispanic, and Asian or Pacific Islander females. When BC screening was recommended to start at age 50 years for all females with a 10-year cumulative risk of BC death of 0.329%, Black females reached this risk threshold level 8 years earlier, at age 42 years, whereas White females reached it at age 51 years, American Indian or Alaska Native and Hispanic females at age 57 years, and Asian or Pacific Islander females 11 years later, at age 61 years. Race and ethnicity-adapted starting ages for Black females were 6 years earlier for mass screening at age 40 years and 7 years earlier for mass screening at age 45 years.

Conclusions and Relevance

This study provides evidence-based race-adapted starting ages for BC screening. These findings suggest that health policy makers may consider a risk-adapted approach to BC screening in which individuals who are at high risk are screened earlier to address mortality due to early-onset BC before the recommended age of mass screening.

Risk of Gynecological Cancers in Cholecystectomized Women: A Large Nationwide Cohort Study

Background: Gallstones affect women more frequently than men, and symptomatic gallstones are increasingly treated with surgical removal of the gallbladder (cholecystectomy). Breast, endometrial, and ovarian cancer share several risk factors with gallstones, including overweight, obesity, and exposure to female sex hormones. We intended to assess the association between cholecystectomy and female cancer risk, which has not been comprehensively investigated. Methods: We investigated the risk of female cancers after cholecystectomy leveraging the Swedish Cancer, Population, Patient, and Death registries. Standardized incidence ratios (SIRs) adjusted for age, calendar period, socioeconomic status, and residential area were used to compare cancer risk in cholecystectomized and non-cholecystectomized women. Results: During a median follow-up of 11 years, 325,106 cholecystectomized women developed 10,431 primary breast, 2888 endometrial, 1577 ovarian, and 705 cervical cancers. The risk of ovarian cancer was increased by 35% (95% confidence interval (CI) 2% to 77%) in the first 6 months after cholecystectomy. The exclusion of cancers diagnosed in the first 6 months still resulted in an increased risk of endometrial (19%, 95%CI 14% to 23%) and breast (5%, 95%CI 3% to 7%) cancer, especially in women cholecystectomized after age 50 years. By contrast, cholecystectomized women showed decreased risks of cervical (-13%, 95%CI -20% to -7%) and ovarian (-6%, 95%CI -10% to -1%) cancer. Conclusions: The risk of ovarian cancer increased by 35% in a just short period of time (6 months) following the surgery. Therefore, it is worth ruling out ovarian cancer before cholecystectomy. Women undergoing cholecystectomy showed an increased risk of breast and endometrial cancer up to 30 years after surgery. Further evaluation of the association between gallstones or gallbladder removal on female cancer risk would allow for the assessment of the need to intensify cancer screening in cholecystectomized women.

Importance of Family History of Colorectal Carcinoma In Situ Versus Invasive Colorectal Cancer: A Nationwide Cohort Study

BACKGROUND

The aim of this study was to explore the risk of invasive colorectal cancer (CRC) in relatives of patients with colorectal carcinoma in situ (CCIS), which is lacking in the literature.

PATIENTS AND METHODS

We collected data from Swedish family-cancer datasets and calculated standardized incidence ratio (SIR) and cumulative risk of CRC in family histories of CCIS in first- and second-degree relatives. Family history was defined as a dynamic (time-dependent) variable allowing for changes during the follow-up period from 1958 to 2015. Of 12,829,251 individuals with available genealogical data, 173,796 were diagnosed with CRC and 40,558 with CCIS.

RESULTS

The lifetime (0-79 years) cumulative risk of CRC in first-degree relatives of patients with CCIS was 6.5%, which represents a 1.6-fold (95% CI, 1.5-1.7; n=752) increased risk. A similarly increased lifetime cumulative risk (6.7%) was found among first-degree relatives of patients with CRC (SIR, 1.6; 95% CI, 1.6-1.7; n=6,965). An increased risk of CRC was also found in half-siblings of patients with CCIS (SIR, 1.9; 95% CI, 1.1-3.0; n=18) and also in half-siblings of patients with CRC (SIR, 1.7; 95% CI, 1.3-2.1; n=78). Moreover, the increased risk of CRC was higher for younger age at diagnosis of CCIS in the affected first-degree relative and for younger age at diagnosis of CRC in the index person.

CONCLUSIONS

Results of this study show that first-degree relatives and half-siblings of patients with CCIS have an increased risk of CRC, which is comparable in magnitude to the risk of those with a family history of invasive CRC. These findings extend available evidence on familial risk of CRC and may help to refine guidelines and recommendations for CRC screening.

Risk of prostate cancer in relatives of prostate cancer patients in Sweden: A nationwide cohort study

BACKGROUND

Evidence-based guidance for starting ages of screening for first-degree relatives (FDRs) of patients with prostate cancer (PCa) to prevent stage III/IV or fatal PCa is lacking in current PCa screening guidelines. We aimed to provide evidence for risk-adapted starting age of screening for relatives of patients with PCa.

METHODS AND FINDINGS

In this register-based nationwide cohort study, all men (aged 0 to 96 years at baseline) residing in Sweden who were born after 1931 along with their fathers were included. During the follow-up (1958 to 2015) of 6,343,727 men, 88,999 were diagnosed with stage III/IV PCa or died of PCa. The outcomes were defined as the diagnosis of stage III/IV PCa or death due to PCa, stratified by age at diagnosis. Using 10-year cumulative risk curves, we calculated risk-adapted starting ages of screening for men with different constellations of family history of PCa. The 10-year cumulative risk of stage III/IV or fatal PCa in men at age 50 in the general population (a common recommended starting age of screening) was 0.2%. Men with ≥2 FDRs diagnosed with PCa reached this screening level at age 41 (95% confidence interval (CI): 39 to 44), i.e., 9 years earlier, when the youngest one was diagnosed before age 60; at age 43 (41 to 47), i.e., 7 years earlier, when ≥2 FDRs were diagnosed after age 59, which was similar to that of men with 1 FDR diagnosed before age 60 (41 to 45); and at age 45 (44 to 46), when 1 FDR was diagnosed at age 60 to 69 and 47 (46 to 47), when 1 FDR was diagnosed after age 69. We also calculated risk-adapted starting ages for other benchmark screening ages, such as 45, 55, and 60 years, and compared our findings with those in the guidelines. Study limitations include the lack of genetic data, information on lifestyle, and external validation.

CONCLUSIONS

Our study provides practical information for risk-tailored starting ages of PCa screening based on nationwide cancer data with valid genealogical information. Our clinically relevant findings could be used for evidence-based personalized PCa screening guidance and supplement current PCa screening guidelines for relatives of patients with PCa.

Risk-adapted starting age of breast cancer screening in women with a family history of ovarian or other cancers: A nationwide cohort study

BACKGROUND

There is a lack of evidence-based recommendations for the age at which women with a family history of cancers other than breast cancer should start breast cancer screening.

METHODS

Using Swedish family cancer data sets, the authors conducted a nationwide cohort study including 5,099,172 Swedish women born after 1931 (follow-up, 1958-2015). Accounting for calendar time, they calculated the relative risk of breast cancer for women with a family history of a discordant cancer in 1 first-degree relative. Furthermore, the authors used 10-year cumulative risk to determine the ages at which women with a family history of discordant cancer reached risk thresholds at which women in the general population were recommended to start breast cancer screening.

RESULTS

A family history of cancer at 15 sites was associated with an increased risk of breast cancer. Among women younger than 50 years, the highest risk of breast cancer was observed for those with a family history of ovarian cancer (standardized incidence ratio, 1.44; 95% confidence interval, 1.26-1.64). In these women, the risk of breast cancer associated with a family history at other cancer sites ranged from 1.08-fold for prostate cancer to 1.18-fold for liver cancer. When breast cancer screening was recommended to be started at the age of 50 years for the general population, women with 1 first-degree relative with ovarian cancer attained the threshold risk for screening at the age of 46 years. Women with a family history of other discordant cancers did not reach the risk thresholds for screening at younger ages.

CONCLUSIONS

Many cancers showed familial associations with breast cancer, but women with a family history of these cancers (except for ovarian cancer) did not reach risk thresholds for screening at younger ages.

Risk of invasive breast cancer in relatives of patients with breast carcinoma in situ: a prospective cohort study

BACKGROUND

Wide implementation of mammography screening has resulted in increased numbers of women diagnosed with breast carcinoma in situ. We aimed to determine the risk of invasive breast cancer in relatives of patients with breast carcinoma in situ in comparison to the risk in relatives of patients with invasive breast cancer.

METHODS

We analyzed the occurrence of cancer in a nationwide cohort including all 5,099,172 Swedish women born after 1931 with at least one known first-degree relative. This was a record linkage study of Swedish family cancer datasets, including cancer registry data collected from January 1, 1958, to December 31, 2015. We calculated standardized incidence ratios (SIRs) and 10-year cumulative risk of breast cancer diagnosis for women with a family history of in situ and invasive breast cancer.

RESULTS

Having one first-degree relative with breast carcinoma in situ was associated with 50% increased risk of invasive breast cancer (SIR = 1.5, 95% CI 1.4-1.7) when compared to those who had no family history of invasive breast cancer or breast carcinoma in situ in either first- or second-degree relatives. Similarly, having one first-degree relative with invasive breast cancer was associated with 70% (1.7, 1.7-1.8) increased risk. The 10-year cumulative risk for women at age 50 with a relative with breast carcinoma in situ was 3.5% (2.9-3.9%) and was not significantly different from 3.7% (3.6-3.8%) risk for 50-year-old women with a relative with invasive breast cancer (95% confidence intervals overlapped).

CONCLUSIONS

The risk of invasive breast cancer for women with a family history of breast carcinoma in situ was comparable to that for women with a family history of invasive breast cancer. Therefore, family history of breast carcinoma in situ should not be overlooked in recommendations for breast cancer prevention for women with a family history of breast cancer.

Risk of colorectal cancer in patients with diabetes mellitus: A Swedish nationwide cohort study

BACKGROUND

Colorectal cancer (CRC) incidence is increasing among young adults below screening age, despite the effectiveness of screening in older populations. Individuals with diabetes mellitus are at increased risk of early-onset CRC. We aimed to determine how many years earlier than the general population patients with diabetes with/without family history of CRC reach the threshold risk at which CRC screening is recommended to the general population.

METHODS AND FINDINGS

A nationwide cohort study (follow-up:1964-2015) involving all Swedish residents born after 1931 and their parents was carried out using record linkage of Swedish Population Register, Cancer Registry, National Patient Register, and Multi-Generation Register. Of 12,614,256 individuals who were followed between 1964 and 2015 (51% men; age range at baseline 0-107 years), 162,226 developed CRC, and 559,375 developed diabetes. Age-specific 10-year cumulative risk curves were used to draw conclusions about how many years earlier patients with diabetes reach the 10-year cumulative risks of CRC in 50-year-old men and women (most common age of first screening), which were 0.44% and 0.41%, respectively. Diabetic patients attained the screening level of CRC risk earlier than the general Swedish population. Men with diabetes reached 0.44% risk at age 45 (5 years earlier than the recommended age of screening). In women with diabetes, the risk advancement was 4 years. Risk was more pronounced for those with additional family history of CRC (12-21 years earlier depending on sex and benchmark starting age of screening). The study limitations include lack of detailed information on diabetes type, lifestyle factors, and colonoscopy data.

CONCLUSIONS

Using high-quality registers, this study is, to our knowledge, the first one that provides novel evidence-based information for risk-adapted starting ages of CRC screening for patients with diabetes, who are at higher risk of early-onset CRC than the general population.

Risk of invasive prostate cancer and prostate cancer death in relatives of patients with prostatic borderline or in situ neoplasia: A nationwide cohort study

BACKGROUND

The question of whether having a family history of prostatic borderline or in situ neoplasia (PBISN) is associated with an increased risk of invasive prostate cancer (PCa) or death from PCa remains unanswered. The objective of the current study was to provide an evidence-based risk estimation for the relatives of patients with PBISN.

METHODS

Nationwide Swedish family cancer data sets were used for the current study, including data regarding all residents of Sweden who were born after 1931 and their parents. Standardized incidence ratios (SIRs), standardized mortality ratios (SMRs), and lifetime cumulative risks of PCa were calculated for men with different constellations of family history. Family history was defined as a dynamic (time-dependent) variable considering changes during follow-up (1958-2015).

RESULTS

Of the 6,343,727 men in the current study, a total of 238,961 developed invasive PCa and 5756 were diagnosed with PBISN during the follow-up. Men with 1 first-degree relative who was diagnosed with PBISN had a 70% increased risk of invasive PCa (SIR, 1.7; 95% confidence interval, 1.5-1.9) and PCa death (SMR, 1.7; 95% confidence interval, 1.3-2.2) compared with men with no family history of PBISN or invasive PCa. These were rather close to estimates in men with 1 first-degree relative diagnosed with invasive PCa (SIR, 2.1 and SMR, 1.8). A higher risk of PCa in family members was found among patients with a family history of PBISN and/or PCa diagnosed before age 60 years. The results in terms of cumulative risk resembled this trend.

CONCLUSIONS

A family history of PBISN appears to be as important as a family history of invasive PCa with regard to an increased risk of invasive PCa or PCa mortality. Such a history should not be overlooked in PCa screening recommendations or in future research regarding familial PCa.

Personal History of Diabetes as Important as Family History of Colorectal Cancer for Risk of Colorectal Cancer: A Nationwide Cohort Study

INTRODUCTION

Diabetes mellitus (DM) and colorectal cancer (CRC) share some risk factors, including lifestyle and metabolic disturbances. We aimed to provide in-depth information on the association of CRC risk, especially early-onset CRC, with DM, family history of CRC, and age at DM diagnosis.

METHODS

A nationwide cohort study was conducted using Swedish family cancer data sets, inpatient, and outpatient registers (follow-up: 1964-2015), including all individuals born after 1931 and their parents (12,614,256 individuals; 559,375 diabetic patients; 162,226 CRC patients).

RESULTS

DM diagnosis before the age of 50 years was associated with a 1.9-fold increased risk of CRC before the age of 50 years (95% CI for standardized incidence ratio: 1.6-2.3) vs 1.3-fold risk of CRC at/after the age of 50 years (1.2-1.4). DM diagnosis before the age of 50 years in those with a family history of CRC was associated with 6.9-fold risk of CRC before the age of 50 years (4.1-12) and 1.9-fold risk of CRC at/after the age of 50 years (1.4-2.5). Diabetic patients had a similar lifetime risk of CRC before the age of 50 years (0.4%, 95% CI: 0.3%-0.4%) to those with only a family history of CRC (0.5%, 0.5%-0.5%), double that of the population (0.2%, 0.2%-0.2%).

DISCUSSION

Our large cohort with valid information on DM and family history of cancer showed that DM is associated with increased risk of CRC in a magnitude close to having family history of CRC. Associations of DM and CRC family history with increased CRC risk were most prominent in young adults. These findings warrant further studies on harms, benefits, and cost-effectiveness of CRC screening in patients with diabetes, especially type 2, at earlier ages than in the general population.

Calculating the Starting Age for Screening in Relatives of Patients With Colorectal Cancer Based on Data From Large Nationwide Data Sets

BACKGROUND & AIMS

Although colorectal cancer (CRC) screening guidelines acknowledge the need for earlier screening for high-risk individuals, such as those with family history of CRC, there is limited information on how many years earlier these high-risk individuals should be screened; current practice is based on weak evidence. We aimed to provide risk-adapted recommendations on the starting age of CRC screening for individuals with different family histories.

METHODS

We collected data from nationwide family-cancer data sets in Sweden and calculated risk-adapted starting ages of screening for individuals with different family histories of CRC. Family history was defined as a dynamic (time-dependent) variable, allowing for changes during the follow-up period of 1958 through 2015.

RESULTS

During a follow-up of 12,829,251 individuals with genealogy information, 173,796 developed CRC. The 10-year cumulative risk for the average-risk population at age 50 years (the guideline-recommended age for screening) was 0.44%. Individuals with different family histories of CRC attained this equivalent 0.44% risk 3-29 years earlier than their peers in the general population without such a family history. For example, individuals with 1 affected first-degree relative diagnosed before age 45 years reached the corresponding risk level 16 years earlier.

CONCLUSIONS

We determined risk-adapted starting ages of CRC screening for close or distant relatives of patients with CRC, using high quality nationwide data sets. These findings might be used in counselling individuals about the appropriate age to start CRC screening, to optimize screening practice, and to supplement guidelines for CRC screening.

Familial risk of breast cancer by dynamic, accumulative, and static definitions of family history

BACKGROUND

Familial breast cancer risk studies usually overlook the dynamic nature of family history.

METHODS

The authors assessed the effect of incorporating the timing of cancer diagnosis events into the assessment of familial risks of breast cancer in first-degree and second-degree relatives in a nationwide cohort study of 5,099,172 women (follow-up was between 1958-2015). Family history was assessed using 3 approaches: 1) as a static variable (ever having a relative with breast cancer); 2) as accumulative history; and 3) as a dynamic variable (time-dependent variable).

RESULTS

For women aged <50 years, familial risk was mostly higher when family history was assessed as a dynamic variable compared with using a static or accumulative family history. For example, the cumulative risk of receiving a breast cancer diagnosis until age 50 years for women with a history of breast cancer in 1 first-degree relative was 2.6% (95% CI, 2.5%-2.7%) using the static method, 2.4% (95% CI, 2.3%-2.4%) using the accumulative method, and 3.1% (95% CI, 3.0%-3.2%) using the dynamic method. Relative risk in women aged <50 years with a breast cancer diagnosis in a sister was 1.40-fold (95% CI, 1.31-fold to 1.48-fold) using the static method, 1.66-fold (95% CI, 1.57-fold to 1.76-fold) using the accumulative method, and 2.28-fold (95% CI, 2.07-fold to 2.51-fold) using the dynamic method.

CONCLUSIONS

The results of the current study demonstrated that assessing family history as static, accumulative, or dynamic results in different familial risk estimates. The answer as to which method to use for family history assessment depends on the implications of the study, with the dynamic method appearing to be better suited for risk stratification studies, the accumulative method being the most convenient in practice and the least favored for risk prediction, and the static method being suitable for etiological impact and risk attribution studies.

Risk-Adapted Starting Age of Screening for Relatives of Patients With Breast Cancer

Importance

Breast cancer screening guidelines acknowledge the need for earlier screening for women at increased risk but provide limited guidance for women with a family history of breast cancer. A risk-adapted starting age of screening for relatives of patients with breast cancer may help supplement current screening guidelines.

Objective

To identify the risk-adapted starting age of breast cancer screening on the basis of a woman's detailed family history.

Design, Setting, and Participants

This nationwide cohort study analyzed data recorded in the Swedish family-cancer data sets. All women born from 1932 onward and with at least 1 known first-degree relative (FDR) were included (N = 5 099 172). Data from January 1, 1958, to December 31, 2015, were collected. Data were analyzed from October 1, 2017, to March 31, 2019.

Exposures

Family history of breast cancer in FDRs and second-degree relatives (SDRs).

Main Outcomes and Measures

Primary invasive breast cancer diagnosis and the age at which women with different constellations of family history attained the risk level at which breast screening is usually recommended.

Results

Of the 5 099 172 women included in the study, 118 953 (2.3%) received a diagnosis of primary invasive breast cancer. A total of 102 751 women (86.4%; mean [SD] age at diagnosis, 55.9 [11.1] years) did not have family history of breast cancer in FDRs and SDRs at the time of their diagnosis. Risk-adapted starting age of breast cancer screening varied by number of FDRs and SDRs with breast cancer diagnosis and the age at diagnosis of the FDRs. For example, for screening recommendation at age 50 years for the general population (2.2% 10-year cumulative risk), women with multiple affected FDRs, with the youngest affected relative receiving a diagnosis before age 50 years, reached the benchmark risk level at age 27 years. When the youngest relative received a diagnosis after age 50 years, however, this risk level was attained at age 36 years.

Conclusions and Relevance

This study identifies possible risk-based starting ages for breast cancer screening based on population-based registers. These results may serve as high-quality evidence to supplement current screening guidelines for relatives of patients with breast cancer.

Risk-tailored starting age of breast cancer screening based on women's reproductive profile: A nationwide cohort study

BACKGROUND

Although reproductive history is recognised to affect the risk of breast cancer, current breast cancer screening guidelines do not consider risk differences by this important factor. As there is a need for an earlier screening in women at increased risk of breast cancer, we provided evidence-based risk-adapted starting age of screening based on different reproductive profiles.

MATERIAL AND METHODS

We conducted a nationwide cohort study including 5,099,172 Swedish women born after 1931. Records of study participants in Swedish Cancer Registry, Multi-generation Register, Cause of Death Register, and national censuses (follow-up, 1958-2015) have been linked. We used 10-year cumulative risk of breast cancer curves to determine the age at which women with different reproductive factors attained the risk level at which breast screening is usually recommended.

RESULTS

The 10-year cumulative risk of breast cancer at age 40, 45 and 50 years in the general population, at which current screening guidelines recommend screening was calculated. We found that women with various reproductive factors (defined by parity and age at first birth) obtained this level of risk at different ages. The difference was between nine years later and three years earlier.

CONCLUSIONS

This study provides the age at which women with particular reproductive profile could start risk-adapted breast cancer screening. This supplies novel information for clinicians and women about when to start breast cancer screening and is an important step towards a personalised screening.

Familial colorectal cancer risk in half siblings and siblings: nationwide cohort study

OBJECTIVE

To explore the risk of colorectal cancer in family members of patients with colorectal cancer, with an emphasis on subtypes of second degree relatives, especially half siblings, which were lacking in the literature.

DESIGN

Ambidirectional cohort study.

SETTING

Nationwide Swedish Family Cancer Data (record linkage).

PARTICIPANTS

All people residing in Sweden and born after 1931, with their biological parents, totalling >16 million individuals (follow-up: 1958-2015); of those with clear genealogy, 173 796 developed colorectal cancer.

MAIN OUTCOME MEASURES

Lifetime (0-79 years) cumulative risk and standardised incidence ratio of colorectal cancer among first degree relatives and second degree relatives.

RESULTS

The overall lifetime cumulative risk of colorectal cancer in siblings of patients was 7%, which represents a 1.7-fold (95% confidence interval 1.6 to 1.7; n=2089) increase over the risk in those without any family history of colorectal cancer. A similarly increased lifetime cumulative risk (6%) was found among half siblings (standardised incidence ratio 1.5, 95% confidence interval 1.3 to 1.8; n=140). The risk in people with colorectal cancer in both a parent and a half sibling (standardised incidence ratio 3.6, 2.4 to 5.0; n=32) was close to the risk in those with both an affected parent and an affected sibling (2.7, 2.4 to 3.0; n=396). Family history of colorectal cancer in only one second degree relative other than a half sibling (without any affected first degree relatives), such as a grandparent, uncle, or aunt, showed minor association with the risk of colorectal cancer.

CONCLUSION

Family history of colorectal cancer in half siblings is similarly associated with colorectal cancer risk to that in siblings. The increase in risk of colorectal cancer among people with one affected second degree relative was negligible, except for half siblings, but the risk was substantially increased for a combination of family history in one affected second degree relative and an affected first degree relative (or even another second degree relative). These evidence based findings provide novel information to help to identify people at high risk with a family history of colorectal cancer that can potentially be used for risk adapted screening.

Telomere length, telomerase reverse transcriptase promoter mutations, and melanoma risk

Telomere repeats at chromosomal ends, critical for genomic integrity, undergo age-dependent attrition and telomere length has been associated with different disorders including cancers. In this study, based on 1469 patients and 1158 healthy controls, we show a statistically significant (P = 6 × 10^-10 ) association between increased telomere length and melanoma risk. Mendelian randomization, using 5 telomere length-associated polymorphisms, ruled out confounding factors or reverse causality and showed association between increased telomere length and melanoma risk with odds ratio of 2.66 (95% confidence interval: 2.07-3.25). Age-dependent telomere attrition was faster in melanoma cases than controls (P = .01). The carriers of a highly penetrant germline -57A>C TERT promoter mutation, in a previously reported melanoma family, had longer telomeres than the noncarriers. The mutation causes increased TERT and telomerase levels through creation of a binding motif for E-twenty six (ETS) transcription factors and the carriers develop melanoma with an early age of onset and rapid progression to metastasis. In analogy, we hypothesize that increased telomere length in melanoma patients reflects stochastic increased telomerase levels due to common genetic variation. Paradoxically, we observed shorter telomeres (P = 1 × 10^-5 ) in primary tumors from unrelated melanoma patients with (121) than without (170) somatic TERT promoter mutations that similar to the germline mutation, also create binding motifs for ETS transcription factors. However, the age-dependent telomere attrition was faster in tumors with the TERT promoter mutations than in those without such mutations. Besides a robust association between increased telomere length and risk, our data show a perturbed telomere homeostasis in melanoma.

Familial risk of pleural mesothelioma increased drastically in certain occupations: A nationwide prospective cohort study

OBJECTIVE

We aimed to explore the effect of occupation on familial risk of pleural mesothelioma in a nationwide cohort study design.

METHOD

The nationwide Swedish Family-Cancer Database includes all Swedes born after 1931 and their biological parents, totalling 16.1 million individuals with about 2.3 million cancer patients. Hazards ratios (HRs) were calculated adjusting for age, sex and region of residence.

RESULTS

Having asbestos-related occupation in the absence of family history of mesothelioma increased risk of mesothelioma more than threefold (adjusted HR = 3.2, 95% confidence interval [CI]: 3.0-3.5). In those who had a history of mesothelioma in their first-degree relatives and an asbestos-related occupation, risk of mesothelioma dramatically increased compared with individuals without such occupations and family history (without chronic obstructive pulmonary disease [COPD] HR = 24, 95% CI: 15-39; with COPD 45, 95% CI: 15-141). In those who had a family history of mesothelioma and no history of an asbestos-related occupation, risk of mesothelioma did not show significant increase compared with those who had no family history of mesothelioma and no asbestos-related occupation (HR = 1.6; 95% CI: 0.7-3.8).

CONCLUSION

First-degree relatives of patients with pleural mesothelioma had a drastic risk of developing this malignancy in case of certain occupations, which shows a gene-environment interaction is probable in risk of mesothelioma.

Importance of tumor location and histology in familial risk of upper gastrointestinal cancers: a nationwide cohort study

Background

Familial clustering of upper gastrointestinal (UGI) cancers and the significance of family history has been addressed previously. We aimed to elucidate the familial risk based on the specified tumor location and histology.

Method

In the Swedish Family-Cancer Database, we determined the familial risk of UGI cancer patients diagnosed (1958-2015) with esophageal and gastric cancer by tumor location using standardized incidence ratios (SIRs).

Results

Risk of esophageal cancer in first-degree relatives (FDRs) of patients with esophageal cancer increased 2.4-fold (SIR 95% CI 2.0-2.8), whereas risk of esophageal cancer in cases with family history of cancer in the middle third of the esophagus increased 3.4-fold (SIR 95% CI 2.1-5.1). Risk of gastric cancer in FDRs increased 1.6-fold (SIR 95% CI 1.5-1.7), occurrence of concordant subsite gastric cancer in the antrum, body, and cardia was 5.5-fold (SIR 95% CI 2.4-11), 4.6-fold (SIR 95% CI 2.6-7.4), and 1.7-fold (SIR 95% CI 1.1-2.5), respectively. Familial risk of concordant histological subtype in esophageal cancer was 4.1-fold for squamous cell carcinoma (SIR 95% CI 3.2-5.2) and 3.6-fold for adenocarcinoma (SIR 95% CI 2.5-5.1). The risk of concordant gastric adenocarcinoma was 1.6-fold for one affected FDR (SIR 95% CI 1.5-1.7), 6.1-fold for two FDRs (SIR 95% CI 4.4-8.4), and 8.6-fold among twins (SIR 95% CI 2.3-22).

Conclusion

Family history of cancer in the lower third of the esophagus and stomach cancer in specific locations such as the antrum, body, and cardia can be considered as important predictive evidence for cancer in the same location in relatives. Our findings might guide endoscopy-based surveillance by introducing subgroups of populations with a higher risk for UGI cancer with particular attention to concordance of location of lesions, which could be a reasonable strategy for early detection, and thus help save more lives.

Risk of second primary cancers in women diagnosed with endometrial cancer in German and Swedish cancer registries

Along with the increasing incidence and favorable prognosis, more women diagnosed with endometrial cancer may develop second primary cancers (SPCs). We aimed at investigating risk of SPCs after endometrial cancer in Germany and Sweden to provide insight into prevention strategies for SPCs. Endometrial cancer patients diagnosed at age ≥15 years in Germany during 1997-2011 and in Sweden nationwide during 1997-2012 were selected. Standardized incidence ratios (SIRs), calculated as the ratio of observed to expected numbers of cases, were used to assess the risk of a specific second cancer after endometrial cancer for both German and Swedish datasets. Among 46,929 endometrial cancer survivors in Germany and 18,646 in Sweden, overall 2,897 and 1,706 SPCs were recorded, respectively. Significantly elevated SIRs were observed in Germany for ovarian (SIR = 1.3; 95%CI:1.1-1.5) and kidney cancers [1.6 (1.3-1.8)], while in Sweden the SIRs were 5.4 (4.6-6.3) and1.4 (1.0-1.9), respectively. Elevated risk for second ovarian endometrioid carcinoma was pronounced after early (<55 years) onset endometrial cancer in Germany [9.0 (4.8-15)] and Sweden [7.7 (5.1-11)]. In Germany elevated risks were found for second ovarian endometrioid carcinoma after endometrioid histology of first endometrial cancer [6.3 (4.0-9.4)] and for second kidney cancer after clear cell histology of endometrial cancer [4.9 (1.6-11)]. We found exceptionally elevated risk of second ovarian endometrioid carcinoma after endometrial cancer of the same histology or of early onset. Risk for second kidney cancer was also increased, particularly after endometrial cancer of clear cell histology. Cancer prevention strategies should focus on these cancers after endometrial cancer diagnosis.

Molecular analysis of the bacille Calmette-Guérin vaccine strain currently being used in Iran

BACKGROUND

In developing countries, tuberculosis (TB) infection control remains a challenge. The bacille Calmette-Guérin (BCG) vaccine is the only effective vaccine available for TB control. Iran uses a local BCG vaccine strain with an unknown substrain.

OBJECTIVE

To investigate the molecular characteristics of the current BCG strain being used in Iran using comparative genomics of the evolutionarily late strains, including BCG vaccines Pasteur, BCG-Danish, BCG-Glaxo, BCG-Prague, BCG-Frappier, BCG-Connaught and BCG-Moreau.

METHODS

A total of 67 different vials of BCG vaccine were cultured. DNA was extracted using the modified cetrimonium bromide (CTAB) method, and multiplex polymerase chain reaction (PCR) was performed to determine four target genomic regions of difference (RD) 1, RD8, RD16 and SenX3-RegX3, and to see whether RD2 and RD14 were present.

RESULTS

Our results showed that all studied batches were Mycobacterium bovis; molecular analysis revealed that the Iranian vaccine strains possess RD8, RD16 and SenX3-RegX3 regions but not RD1, RD2 and RD14. All of the vaccine batches analysed were compatible with BCG-Pasteur 1173p2, the original strain.

CONCLUSION

All of the BCG strains studied were recognised as the BCG-Pasteur 1173p2 strain. No genetic diversity among stocks and ready-for-use vaccine vials were detected.

Abstract 2556: Family history of colorectal cancer in half-siblings as important as in siblings

Background: None of population-based epidemiological studies to date have investigated the familial risk of colorectal cancer (CRC) in half-siblings. We aimed to compare lifetime (0-79 years) cumulative risk (LCR) and relative risk of CRC between siblings and half-siblings of patients with CRC.

Methods: A nationwide cohort of first-degree relatives and half-siblings of CRC patients diagnosed in 1958-2012 were extracted from the Swedish Family-Cancer Database, the world's largest of its kind, with &gt;15.7 million individual records. LCR as a tangible measure of absolute risk was also calculated. Standardized incidence ratios (SIRs) were adjusted for age, sex, period at diagnosis, and socioeconomic status. All family histories reported below are exclusive, meaning that risk reported for one affected half-sibling does not include those with both an affected half-sibling and any other first/second-degree relatives.

Results: The overall LCR of CRC in siblings of a patient with CRC was 7.2% (8.3% in men; 6.0% in women), which represents 1.8-fold (95%CI = 1.7-1.1.9, n = 1333) increase over the risk in those without any family history of CRC (men 4.5%; women 3.4%). Similarly, significantly increased LCR (5.9%) was found among half-siblings of CRC patients (SIR = 1.7, 95%CI = 1.3-2.0, n = 88; maternal half-sibling: 1.6, 95%CI = 1.1-2.1; paternal half-sibling: 1.7, 95%CI = 1.3-2.3). If a parent and a half-sibling both had CRC, the risk in other half-siblings (SIR = 4.4, 95%CI = 2.8-6.5, n = 24) was closer to that of those with both an affected parent and an affected sibling (SIR = 3.2, 95%CI = 2.9-3.6, n = 281) rather than an affected parent alone (SIR = 1.6, 95%CI = 1.5-1.7, n = 4250). Highly increased risk of CRC was also found in those with two (SIR = 2.4, 95%CI = 1.8-3.1, n = 59) or three (SIR = 9.8, 95%CI = 5.1-17, n = 12) affected siblings, in twin brothers (SIR = 4.0, 95%CI = 2.2-6.6, n = 14), and presumably in men with two affected half-siblings (SIR = 5.3, 95%CI = 1.1-16, n = 3). Other second-degree relatives such as grandparents (SIR = 1.2, 95%CI = 1.1-1.3, n = 318), aunts/uncles (SIR = 1.3, 95%CI = 1.0-1.5, n = 107) without an affected first-degree relative showed minor contributions to the familial risk of CRC, but we found higher risks for those with both an affected first-degree relative and a grandparent (SIR = 3.2, 95%CI = 2.3-4.2, n = 46) or an aunt/uncle (SIR = 2.3, 95%CI = 1.2-4.0, n = 13).

Conclusions: This study provides novel information, which is useful for the genetic counseling. In the cancer risk estimation for relatives of CRC patients, a family history of CRC in a half-sibling (even in the absence of an affected first-degree relative) is as important as a family history of CRC in a sibling.

Citation Format: Mahdi Fallah, Elham Kharazmi, Kristina Sundquist, Hermann Brenner, Kari Hemminki. Family history of colorectal cancer in half-siblings as important as in siblings. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 2556.

GHSR DNA hypermethylation is a common epigenetic alteration of high diagnostic value in a broad spectrum of cancers

Identification of a single molecular trait that is determinant of common malignancies may serve as a powerful diagnostic supplement to cancer type-specific markers. Here, we report a DNA methylation mark that is characteristic of seven studied malignancies, namely cancers of lung, breast, prostate, pancreas, colorectum, glioblastoma and B cell chronic lymphocytic leukaemia (CLL) (n = 137). This mark was defined by substantial hypermethylation at the promoter and first exon of growth hormone secretagouge receptor (GHSR) through bisulfite pyrosequencing. The degree of aberrant methylation was capable of accurate discrimination between cancer and control samples. The highest sensitivity and specificity of cancer detection was achieved for cancers of pancreas, lung, breast and CLL yielding the area under the curve (AUC) values of 1.0000, 0.9952, 0.9800 and 0.9400, respectively. Narrowing to a single CpG site within the gene's promoter or four consecutive CpG units of the highest methylation levels within the first exon improved the detection power. GHSR hypermethylation was detected already at the early stage tumors. The accurate performance of this marker was further replicated in an independent set of pancreatic cancer and control samples (n = 78). These findings support the candidature of GHSR methylation as a highly accurate pan-cancer marker.

Abstract 2740: Familial Hodgkin lymphoma by relationship, sex, age and histology: a joint study from five Nordic countries

Background: We aimed to estimate lifetime (0-79 years) cumulative risk (CR) of Hodgkin lymphoma (HL) in relatives of patients with HL by relationship, sex, age and histology.

Design: A population-based cohort of 57,475 first-degree relatives of 13,922 HL patients diagnosed in 1955-2009 in Nordic countries was followed for cancer incidence. Standardized incidence ratios (SIRs) were calculated using histology-, age-, sex-, period-, and country-specific incidence rates as the reference.

Results: The overall CR of HL in first-degree relatives of a patient with Hodgkin lymphoma was 0.6%, which represents 3-fold (SIR = 3.3, 95%CI = 2.8-3.9) increase over the general population risk (men 0.3%; women 0.2%). Significantly high CR (1%) was found among sisters with early-onset HL and unlike-sex siblings with HL diagnosed at age 30-59. The familial risk in sisters (9-fold) was higher than in brothers (4.5-fold) or unlike-sex siblings (6-fold). In general, the risk in siblings (6-fold) was higher than in parents/children (2-fold). Very high risk of HL was found for few men with two HL first-degree relatives (3-8%) and for twin brothers (18%). For the first time we found high familial risk of concordant histological subtypes of HL [lymphocyte-rich (81-fold, n = 6) and nodular sclerosis (4.6-fold, n = 22)] and also discordant subtypes.

Conclusions: Lymphocytic-rich histology type of HL showed highest familial risk. The absolute risk of familial HL was generally less than 1.5%, except for men with multiple affected first-degree relatives (3-8%), twin brothers (18%), or brothers with early-onset HL (2%).

Citation Format: Mahdi Fallah, Elham Kharazmi, Eero Pukkala, Jørgen H. Olsen, Laufey Tryggvadottir, Kristina Sundquist, Steinar Tretli, Kari Hemminki. Familial Hodgkin lymphoma by relationship, sex, age and histology: a joint study from five Nordic countries. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 2740. doi:10.1158/1538-7445.AM2015-2740

Abstract 2743: Cancer risk in relatives of testicular cancer patients by histology type and age at diagnosis: a joint study from five Nordic countries

Background: None of population-based epidemiological studies to date had a large enough sample size to show familial risk of testicular cancer (TC) by patients’ and their relatives’ age at diagnosis and also by rare histological subtypes.

Objective: We aimed to estimate absolute and relative risk of TC in relatives of TC patients by age at diagnosis in patients and their relatives and histology subtypes.

Design: A joint population-based cohort study.

Setting and Participants: A cohort of 97,402 first-degree relatives of 21,254 TC patients who were diagnosed between1955 and 2010 in five European countries was followed for cancer incidence.

Outcome Measurements and Statistical Analysis: Standardized incidence ratios (SIRs) were estimated using histology-, age-, period-, and country-specific incidence rates as the reference. The lifetime cumulative risks also were calculated.

Results and Limitations: The lifetime cumulative risk of TC in brothers of a patient with TC was 2.3%, which represents 4-fold increased risk (SIR = 4.1, 95%CI = 3.6-4.6) over the general population risk. TC in a father increased the risk up to 2-fold in his son (95%CI = 1.7-2.4; lifetime risk 1.2%) and vice versa. When there were ≥2 TC patients diagnosed in a family, lifetime TC risk for relatives was 10-11%. Depending on age at diagnosis, twins had 9-74% lifetime risk of TC. Family history of most of the histological subtypes of TC increased the risk for concordant and most of the discordant subtypes. There was a tendency toward concordant age at diagnosis of TC among relatives.

Conclusions: This study provides clinically relevant age-specific cancer risk estimates for family members of TC patients. Familial TC cases tended to develop TC at an age close to age at diagnosis of TC among their relatives, which is the novel finding of this study.

Citation Format: Elham Kharazmi, Kari Hemminki, Eero Pukkala, Kristina Sundquist, Laufey Tryggvadottir, Steinar Tretli, Jørgen H. Olsen, Mahdi Fallah. Cancer risk in relatives of testicular cancer patients by histology type and age at diagnosis: a joint study from five Nordic countries. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 2743. doi:10.1158/1538-7445.AM2015-2743

Risk assessment of gas oil and kerosene contamination on some properties of silty clay soil

Soil and ground water resource pollution by petroleum compounds and chemical solvents has multiple negative environmental impacts. The aim of this research was to investigate the impacts of kerosene and gas oil pollutants on some physical and chemical properties, breakthrough curve (BTC), and water retention curve (SWRC) of silty clay soil during a 3-month period. Therefore, some water-saturated soils were artificially contaminated in the pulse condition inside some glassy cylinders by applying half and one pore volume of these pollutants, and then parametric investigations of the SWRC were performed using RETC software for Van Genukhten and Brooks-Corey equations in the various suctions and the soil properties were determined before and after pollution during 3 months. The results showed that gas oil and kerosene had a slight effect on soil pH and caused the cumulative enhancement in the soil respiration, increase in the bulk density and organic matter, and reduction in the soil porosity and electrical and saturated hydraulic conductivity. Furthermore, gas oil retention was significantly more than kerosene (almost 40%) in the soil. The survey of SWRC indicated that the contaminated soil samples had a little higher amount of moisture retention (just under 15% in most cases) compared to the unpolluted ones during this 3-month period. The parametric analysis of SWRC demonstrated an increase in the saturated water content, Θ s, from nearly 49% in the control sample to just under 53% in the polluted ones. Contaminants not only decreased the residual water content, Θ r, but also reduced the SWRC gradient, n, and amount of α parameter. The evaluation of both equations revealed more accurate prediction of SWRC's parameters by Van Genukhten compared to those of Brooks and Corey.

The risk of contralateral breast cancer in daughters of women with and without breast cancer

We aimed to estimate the 15-year and lifetime risks of contralateral breast cancer in breast cancer patients according to the age of diagnosis of the first cancer and the history of breast cancer in the mother. The risks of contralateral breast cancer were estimated for all 78,775 breast cancer patients in the Swedish Family-Cancer Database (age at diagnosis of first breast cancer <70 years). The risk of experiencing a contralateral breast cancer within 15 years of diagnosis was 8.4% [95% confidence interval (CI): 8.1-8.7%] for women with an unaffected mother, was 12% (95%CI: 11-13%) for a woman with a mother with unilateral breast cancer and was 13% (95%CI: 9.5-17%) for women with a mother with bilateral breast cancer. In early-onset diagnosed women (<50 years) with an unaffected mother, the risk of contralateral breast cancer until age 80 was 23% (95%CI: 20-26%) and for late-onset (50-69 years) diagnosed women it was 17% (95%CI: 14-21%). In a woman with a mother with an early-onset unilateral breast cancer, risk of contralateral breast cancer by age 80 was 35% (95%CI: 25-46%). Women with a mother with early-onset bilateral breast cancer had 31% (95%CI: 12-67%) lifetime risk of contralateral breast cancer. The risk of contralateral breast cancer is higher for daughters of breast cancer patients than for daughters of women without breast cancer. Maternal cancer history and age at onset of first breast cancer in women should be taken into account when counseling breast cancer patients about their risk of contralateral breast cancer.

A simple-to-use method incorporating genomic markers into prostate cancer risk prediction tools facilitated future validation

OBJECTIVES

To incorporate single-nucleotide polymorphisms (SNPs) into the Prostate Cancer Prevention Trial Risk Calculator (PCPTRC).

STUDY DESIGN AND SETTING

A multivariate random-effects meta-analysis of likelihood ratios (LRs) for 30 validated SNPs was performed, allowing the incorporation of linkage disequilibrium. LRs for an SNP were defined as the ratio of the probability of observing the SNP in prostate cancer cases relative to controls and estimated by published allele or genotype frequencies. LRs were multiplied by the PCPTRC prior odds of prostate cancer to provide updated posterior odds.

RESULTS

In the meta-analysis (prostate cancer cases/controls = 386,538/985,968), all but two of the SNPs had at least one statistically significant allele LR (P < 0.05). The two SNPs with the largest LRs were rs16901979 [LR = 1.575 for one risk allele, 2.552 for two risk alleles (homozygous)] and rs1447295 (LR = 1.307 and 1.887, respectively).

CONCLUSION

The substantial investment in genome-wide association studies to discover SNPs associated with prostate cancer risk and the ability to integrate these findings into the PCPTRC allows investigators to validate these observations, to determine the clinical impact, and to ultimately improve clinical practice in the early detection of the most common cancer in men.

Metastatic sites and survival in lung cancer

OBJECTIVES

Population-based data on metastatic sites and survival in site-specific metastases are lacking for lung cancer and for any cancer because most cancer registries do not record metastases. This study uses a novel population-based approach to identify metastases from both death certificates and national inpatient data to describe metastatic pathways in lung cancer patients.

MATERIALS AND METHODS

17,431 deceased lung cancer patients diagnosed 2002-2010 were identified from the nationwide Swedish Cancer Registry, which is based on compulsory reports. The influence of age at diagnosis, sex, and histological subtype on metastatic spread was investigated. Survival in metastatic lung cancer was assessed by histology and metastatic site.

RESULTS

The most frequent metastatic sites were the nervous system, bone, liver, respiratory system, and adrenal gland. Liver (35%) and nervous system (47%) metastases were common in patients with metastases from small cell lung cancer, and bone (39%) and respiratory system (22%) metastases in adenocarcinoma. Women (43% vs. 35%) and younger patients had more metastases to the nervous system. Median survival after diagnosis was 13 months for non-metastatic and five months for metastatic lung cancer. In this novel data, liver metastases conferred the worst prognosis (three months), especially for large cell histology. Bone metastases also featured poor survival, whereas survival in respiratory and nervous system metastases was better.

CONCLUSION

Metastatic sites and survival in metastatic lung cancer is influenced by sex, histological subtype, and age at diagnosis. Liver and bone metastases signal poor survival, compared with nervous system metastases.

Abstract 1293: Familial melanoma by histology and age guiding clinical genetic counseling: joint data from five Nordic countries

Background: We aimed to estimate lifetime cumulative risk of melanoma (CRM) in relatives of patients with melanoma by histology and age at diagnosis in patients and relatives.

Methods: A population-based cohort of 238,724 first-degree relatives of 46,091 melanoma patients diagnosed in 1955-2010 in Nordic countries was followed for cancer incidence.

Findings: The CRM (0-79 years) in first-degree relatives of a patient with superficial spreading (SSM), nodular (NM), or lentigo maligna (LMM) melanoma was quite similar, ranging from 2.5% to 2.9%, which represents about 2-fold increase over the general population risk. When one melanoma patient in the family was diagnosed before age 30, the CRM was 3.2%. When there were ≥2 melanoma patients diagnosed before age 30 in a family, CRM for relatives was 13.8%, 5.8% for diagnoses at age 30-59, and 4.8% for diagnoses at age 60 or older. Depending on age at diagnosis of same-sex twins (not known whether monozygotic or dizygotic), their CRM was 7.4-21.3%. Although no familial case of concordant histological types of acral lentiginous/desmoplastic/compound nevus/spindle cell melanomas or malignant blue nevus (MBN) was found, familial risks of discordant histological types of melanoma were interchangeably high for most of the types, e.g. higher risk of SSM when a first-degree relative had NM [standardized incidence ratios (SIR)=2.6, 95%CI=2.1-3.3, n=72] or ALM (4.0, 95%CI=1.5-8.8, n=6) and vice versa. There was a tendency toward concordant age at diagnosis of melanoma among relatives of melanoma patients.

Interpretation: This study provides clinically relevant absolute and relative risk estimates for family members of melanoma patients by age at diagnosis in patients and relatives. Our finding may suggest that the role of genetic or environmental factors in the differentiation of histological types of melanoma is not as strong as its role in the development of melanoma as such.

Citation Format: Mahdi Fallah, Eero Pukkala, Kristina Sundquist, Steinar Tretli, Jørgen H. Olsen, Laufey Tryggvadottir. Familial melanoma by histology and age guiding clinical genetic counseling: joint data from five Nordic countries. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 1293. doi:10.1158/1538-7445.AM2014-1293

Incorporation of detailed family history from the Swedish Family Cancer Database into the PCPT risk calculator

PURPOSE

A detailed family history provides an inexpensive alternative to genetic profiling for individual risk assessment. We updated the PCPT Risk Calculator to include detailed family histories.

MATERIALS AND METHODS

The study included 55,168 prostate cancer cases and 638,218 controls from the Swedish Family Cancer Database who were 55 years old or older in 1999 and had at least 1 male first-degree relative 40 years old or older and 1 female first-degree relative 30 years old or older. Likelihood ratios, calculated as the ratio of risk of observing a specific family history pattern in a prostate cancer case compared to a control, were used to update the PCPT Risk Calculator.

RESULTS

Having at least 1 relative with prostate cancer increased the risk of prostate cancer. The likelihood ratio was 1.63 for 1 first-degree relative 60 years old or older at diagnosis (10.1% of cancer cases vs 6.2% of controls), 2.47 if the relative was younger than 60 years (1.5% vs 0.6%), 3.46 for 2 or more relatives 60 years old or older (1.2% vs 0.3%) and 5.68 for 2 or more relatives younger than 60 years (0.05% vs 0.009%). Among men with no diagnosed first-degree relatives the likelihood ratio was 1.09 for 1 or more second-degree relatives diagnosed with prostate cancer (12.7% vs 11.7%). Additional first-degree relatives with breast cancer, or first-degree or second-degree relatives with prostate cancer compounded these risks.

CONCLUSIONS

A detailed family history is an independent predictor of prostate cancer compared to commonly used risk factors. It should be incorporated into decision making for biopsy. Compared with other costly biomarkers it is inexpensive and universally available.