The Cooperative Familial Registry for Breast Cancer Studies: design and first year recruitment rates in Ontario

Recruiting families at risk for hereditary breast and ovarian cancer from a statewide cancer registry: a methodological study

PURPOSE

Cancer genetic services (counseling/testing) are recommended for women diagnosed with breast cancer younger than 45 years old (young breast cancer survivors-YBCS) and at-risk relatives. We present recruitment of YBCS, identification and recruitment of at-risk relatives, and YBCS willingness to contact their cancer-free, female relatives.

METHODS

A random sample of 3,000 YBCS, stratified by race (Black vs. White/Other), was identified through a population-based cancer registry and recruited in a randomized trial designed to increase use of cancer genetic services. Baseline demographic, clinical, and family characteristics, and variables associated with the Theory of Planned Behavior (TPB) were assessed as predictors of YBCS' willingness to contact at-risk relatives.

RESULTS

The 883 YBCS (33.2% response rate; 40% Black) who returned a survey had 1,875 at-risk relatives and were willing to contact 1,360 (72.5%). From 853 invited at-risk relatives (up to two relatives per YBCS), 442 responded (51.6% response rate). YBCS with larger families, with a previous diagnosis of depression, and motivated to comply with recommendations from family members were likely to contact a greater number of relatives. Black YBCS were more likely to contact younger relatives and those living further than 50 miles compared to White/Other YBCS.

CONCLUSION

It is feasible to recruit diverse families at risk for hereditary cancer from a population-based cancer registry. This recruitment approach can be used as a paradigm for harmonizing processes and increasing internal and external validity of large-scale public health genomic initiatives in the era of precision medicine.

Family-based genetic association study of insulin-like growth factor I microsatellite markers and premenopausal breast cancer risk

Several studies suggest that higher circulating insulin-like growth factor I (IGF-I) levels are associated with premenopausal breast cancer risk. Breast cancer risk and circulating IGF-I concentration appear to be partly heritable, thus genetic variation at IGF1 could influence IGF-I levels and breast cancer risk. We investigated the association of IGF1 CA repeat variants with premenopausal breast cancer risk using a family-based design. The study sample included 840 families from the Ontario Familial Breast Cancer Registry (OFBCR) and the Australian Breast Cancer Family Registry (ABCFR). Three CA repeat variants, at 5', 3', and in intron 2 were genotyped (5'CA, 3'CA, In2CA). We found several nominally significant associations. The 5'CA-21 allele (P = 0.03) and In2CA-212 allele (P = 0.04) were associated with lower risk, and the In2CA-216 allele with higher risk (P = 0.04) for the combined ABCFR-OFBCR. These associations were not significant after taking into account multiple comparisons. In2CA-216 was more strongly associated with risk when we used a recessive instead of an additive model (P = 0.01). 5'CA alleles of repeat length 18-20 were associated with higher risk (P = 0.02), and 5'CA alleles of >20 repeats were associated with lower risk (P = 0.01). These associations were significant in the OFBCR (In2CA-216 recessive, P = 0.02; 5'CA 18-20 and >20 allele grouping, P = 0.01) but not strongly supported by the ABCFR (In2CA-216 recessive, P = 0.14; 5'CA 18-20, P = 0.25; 5'CA >20, P = 0.20). The associations we found could be due to chance as many comparisons were made. Our results do not strongly support an association between these IGF1 variants and breast cancer risk.

Expression profiling of familial breast cancers demonstrates higher expression of FGFR2 in BRCA2-associated tumors

BackgroundBRCA1- and BRCA2-associated tumors appear to have distinct molecular signatures. BRCA1-associated tumors are predominantly basal-like cancers, whereas BRCA2-associated tumors have a predominant luminal-like phenotype. These two molecular signatures reflect in part the two cell types found in the terminal duct lobular unit of the breast. To elucidate novel genes involved in these two spectra of breast tumorigenesis we performed global gene expression analysis on breast tumors from germline BRCA1 and BRCA2 mutation carriers. Methodology Breast tumor RNAs from 7 BRCA1 and 6 BRCA2 mutation carriers were profiled using UHN human 19K cDNA microarrays. Supervised univariate analyses were conducted to identify genes differentially expressed between BRCA1 and BRCA2-associated tumors. Selected discriminatory genes were validated using real time reverse transcription polymerase chain reaction in the tumor RNAs, and/or by immunohistochemistry (IHC) or by in situ hybridization (ISH) on tissue microarrays (TMAs) containing an independent set of 58 BRCA1 and 64 BRCA2-associated tumors. Results Genes more highly expressed in BRCA1-associated tumors included stathmin, osteopontin, TGFβ2 and Jagged 1 in addition to genes previously identified as characteristic of basal-like breast cancers. BRCA2-associated cancers were characterized by the higher relative expression of FGF1 and FGFR2. FGFR2 protein was also more highly expressed in BRCA2-associated cancers (P = 0.004). SignificanceBRCA1-associated tumours demonstrated increased expression of component genes of the Notch and TGFβ pathways whereas the higher expression of FGFR2 and FGF1 in BRCA2-associated cancers suggests the existence of an autocrine stimulatory loop.

Testing three different cancer genetics registry recruitment methods with Hispanic cancer patients and their family members previously registered in local cancer registries in Texas

OBJECTIVE

To increase accrual among Hispanics to the Cancer Genetics Network national cancer genetics registry.

METHODS

Drawing from South Texas cancer registries, 444 Hispanic men and women were randomly assigned to one of three experimental conditions: standard direct-mailed procedures (X1), X1 plus culturally tailored materials (X2), and X2 plus interpersonal phone contact (X3). Participants were also surveyed about the effectiveness of the education materials and the phone contact. A refusal survey was provided for those who declined to join the study.

RESULTS

A total of 154 individuals joined the Cancer Genetics Network. The X3 condition yielded the greatest accrual (43.2%) compared to X1 (30.9%) and X2 (29.9%; p < 0.05). Tailored materials appeared to have no effect but were highly regarded. The main reasons for not participating were a lack of interest and time requirements.

CONCLUSION

Interpersonal communication can have a powerful effect on recruitment. However, more research is needed to determine the cost-efficacy of more labor-intensive approaches to registry accrual.

When research seems like clinical care: a qualitative study of the communication of individual cancer genetic research results

Background

Research ethicists have recently declared a new ethical imperative: that researchers should communicate the results of research to participants. For some analysts, the obligation is restricted to the communication of the general findings or conclusions of the study. However, other analysts extend the obligation to the disclosure of individual research results, especially where these results are perceived to have clinical relevance. Several scholars have advanced cogent critiques of the putative obligation to disclose individual research results. They question whether ethical goals are served by disclosure or violated by non-disclosure, and whether the communication of research results respects ethically salient differences between research practices and clinical care. Empirical data on these questions are limited. Available evidence suggests, on the one hand, growing support for disclosure, and on the other, the potential for significant harm.

Methods

This paper explores the implications of the disclosure of individual research results for the relationship between research and clinical care through analysis of research-based cancer genetic testing in Ontario, Canada in the late 1990s. We analyze a set of 30 interviews with key informants involved with research-based cancer genetic testing before the publicly funded clinical service became available in 2000.

Results

We advance three insights: First, the communication of individual research results makes research practices seem like clinical services for our respondents. Second, while valuing the way in which research enables a form of clinical access, our respondents experience these quasi-clinical services as inadequate. Finally, our respondents recognize the ways in which their experience with these quasi-clinical services is influenced by research imperatives, but understand and interpret the significance and appropriateness of these influences in different ways.

Conclusion

Our findings suggest that the hybrid state created through the disclosure of research results about individuals that are perceived to be clinically relevant may produce neither sufficiently adequate clinical care nor sufficiently ethical research practices. These findings raise questions about the extent to which research can, and should, be made to serve clinical purposes, and suggest the need for further deliberation regarding any ethical obligation to communicate individual research results.

Polymorphisms cMyc-N11S and p27-V109G and breast cancer risk and prognosis

BACKGROUND

cMyc and p27 are key genes implicated in carcinogenesis. Whether polymorphisms in these genes affect breast cancer risk or prognosis is still unclear. In this study, we focus on a rare non-synonymous polymorphism in cMyc (N11S) and a common polymorphism in p27 (V109G) and determine their role in risk and prognosis using data collected from the Ontario Breast Cancer Family Registry.

METHODS

Risk factor data was collected at baseline on a large group of women (cases = 1,115 and population-based controls = 710) and clinical data (including treatment and follow-up) were collected prospectively by periodic review of medical records for a subset of cases (N = 967) for nearly a decade. A centralized pathology review was conducted. Unconditional logistic regression was used to determine the association of polymorphisms with breast cancer risk and the Cox proportional hazards model was used to determine their association with survival.

RESULTS

Our results suggest that while cMyc-N11S can be considered a putatively functional polymorphism located in the N-terminal domain, it is not associated with risk, tumor characteristics or survival. The p27-G109 allele was associated with a modest protective effect in adjusted analyses and higher T stage. We found no evidence to suggest that p27-V109G alone or in combination with cMyc-N11S was associated with survival. Age at onset and first-degree family history of breast or ovarian cancer did not significantly modify the association of these polymorphisms with breast cancer risk.

CONCLUSION

Further work is recommended to understand the potential functional role of these specific non-synonymous amino acid changes and a larger, more comprehensive investigation of genetic variation in these genes (e.g., using a tagSNP approach) in combination with other relevant genes is needed as well as consideration for treatment effects when assessing their potential role in prognosis.

Influence of young age at diagnosis and family history of breast or ovarian cancer on breast cancer outcomes in a population-based cohort study

PURPOSE

The objective of this study was to examine the association of: (i) diagnosis at age </=35, (ii) first-degree family history of breast or ovarian cancer (BOC) and (iii) a research based definition of genetic risk, with tumor characteristics, treatment and survival in breast cancer (BC).

PATIENTS AND METHODS

Consenting female participants in the population-based Ontario Familial Breast Cancer Registry diagnosed with primary invasive BC between 1996 and 1998 were followed prospectively until 2005.

RESULTS

Among 967 women, 105 were </=35 years old at diagnosis and 686 were classified as genetic risk cases, including 349 with a first-degree family history. Individuals diagnosed at age </=35 were more likely to self-detect tumors, to present with inflammatory BC, to have invasive ductal carcinoma of no special type, high T stage, and tumors with lymphovascular invasion (LVI), high grade and negative estrogen receptors. Younger women were more likely to receive chemotherapy and less likely to receive hormonal therapy. Diagnosis </=35 years old was associated with significantly reduced distant recurrence free survival, an effect that did not persist after adjustment for tumor and treatment related variables. Poor outcomes were restricted to younger women with hormone responsive BC. Family history was associated with increased rates of mammographic detection of BC, lower tumor stage and less frequent inflammatory BC, but had no association with BC outcomes.

CONCLUSION

Women diagnosed with BC at age </=35 have more aggressive tumors; these adverse tumor characteristics, rather than age, lead to poor outcomes. Family history was not associated with survival.

Predictors of participation in clinical and psychosocial follow-up of the kConFab breast cancer family cohort

INTRODUCTION

Prospective collection of epidemiological, psychosocial and outcome data in large breast cancer family cohorts should provide less biased data than retrospective studies regarding penetrance of breast cancer and modifiers of genetic risk.

METHODS

The Kathleen Cuningham Foundation for Research into Breast Cancer (kConFab) recently commenced 3-yearly follow-up on over 750 families with multiple cases of breast cancer. Clinical follow-up was by mailed self-report questionnaire to all participants, while psychosocial follow-up was only of unaffected women and consisted of two components: a mailed questionnaire and an interview regarding stressful life events.

RESULTS

To date, 1928 of 2748 (70%) participants returned the clinical follow-up questionnaire (10% opted out, 16% were non-responders, and 4% were not contactable). Of the unaffected females who returned the clinical follow-up questionnaire, 91% participated in the psychosocial follow-up. In multivariate analyses, sex, personal cancer status, marital status, age and educational status were independent predictors of response to the clinical follow-up questionnaire, and number of female children, age, and family history of breast cancer were independent predictors of response to the psychosocial follow-up.

CONCLUSIONS

A first round of 3-yearly clinical and psychosocial follow-up using a mailed questionnaire was feasible in this cohort. High response rates were achieved by employing intensive tracing and reminder strategies. The predictors of response for the clinical and psychosocial follow-up components of this study should be considered in designing similar follow-up strategies for other family cancer cohorts.

A survey of the SWISS researchers on the impact of sibling privacy protections on pedigree recruitment

To understand the perceptions and attitudes about privacy safeguards in research and investigate the impact of letter-based proband-initiated contact on recruitment, we surveyed researchers in the Siblings With Ischemic Stroke Study (SWISS). All 49 actively recruiting sites provided at least 1 response, and 61% reported that potential probands were enthusiastic. Although 66% of researchers valued proband-initiated contact, only 23% said that probands viewed this strategy as important to protecting the privacy of siblings. A substantial minority of researchers (37%) said the strategy impeded enrollment, and 44% said it was overly burdensome to probands.

Polymorphisms XRCC1-R399Q and XRCC3-T241M and the Risk of Breast Cancer at the Ontario Site of the Breast Cancer Family Registry

This study investigates the role of two nonsynonymous single nucleotide polymorphisms in DNA repair genes, X-ray repair cross-complementing group 1 (XRCC1)-R399Q and X-ray repair cross-complementing group 3 (XRCC3)-T241M, in breast cancer. Incident cases of invasive breast cancer in Caucasian women [n = 402, mean age = 45.7 (SD = 6.2) years] and female Caucasian controls [n = 402, mean age = 45.2 (6.5) years] frequency matched on 5-year age intervals were identified from the Ontario Familial Breast Cancer Registry. No evidence for a main effect of the XRCC1-R399Q genotype on breast cancer risk was observed. Estimates of risk for a family history (FH) of breast cancer compared with no FH differed by XRCC1-R399Q genotype (P value for interaction = 0.001). Homozygote XRCC1-399 R/R individuals and FH+ were at a 2.92-fold [95% confidence interval (95% CI) = 1.47–5.79] increased risk of disease compared with FH− individuals; the estimate of risk increased for R/Q heterozygotes with FH+ [odds ratio (OR) = 3.85, 95% CI = 1.94–7.65] but not for Q/Q homozygotes with FH+ (OR = 0.54, 95% CI = 0.20–1.47) compared with homozygous R/R and FH− individuals. A marginal positive association for XRCC3-241 M/M compared with T/T genotype was found (OR = 1.44, 95% CI = 0.94–2.19), but the heterozygous T/M was not associated with an increase in risk (OR = 0.96, 95% CI = 0.71–1.32). There was also some evidence for a combined effect of body mass index and XRCC3-T241M on estimates of risk. Our results suggest that these polymorphisms may influence breast cancer risk by modifying the effect of risk factors such as FH. There is a need for further study into the role of these polymorphisms as effect modifiers.

Regressive logistic and proportional hazards disease models for within-family analyses of measured genotypes, with application to a CYP17 polymorphism and breast cancer

Various statistical methods have been proposed to evaluate associations between measured genetic variants and disease, including some using family designs. For breast cancer and rare variants, we applied a modified segregation analysis method that uses the population cancer incidence and population-based case families in which a mutation is known to be segregating. Here we extend the method to a common polymorphism, and use a regressive logistic approach to model familial aggregation by conditioning each individual on their mother's breast cancer history. We considered three models: 1) class A regressive logistic model; 2) age-of-onset regressive logistic model; and 3) proportional hazards familial model. Maximum likelihood estimates were calculated using the software MENDEL. We applied these methods to data from the Australian Breast Cancer Family Study on the CYP17 5'UTR T-->C MspA1 polymorphism measured for 1,447 case probands, 787 controls, and 213 relatives of case probands found to have the CC genotype. Breast cancer data for first- and second-degree relatives of case probands were used. The three methods gave consistent estimates. The best-fitting model involved a recessive inheritance, with homozygotes being at an increased risk of 47% (95% CI, 28-68%). The cumulative risk of the disease up to age 70 years was estimated to be 10% or 22% for a CYP17 homozygote whose mother was unaffected or affected, respectively. This analytical approach is well-suited to the data that arise from population-based case-control-family studies, in which cases, controls and relatives are studied, and genotype is measured for some but not all subjects.

A population-based study of the extent of surgical resection of potentially curable colon cancer

BACKGROUND

We attempted to determine factors contributing to the extent of initial curative resection for colon cancer in a population-based cohort. Total abdominal colectomy with ileorectal anastomosis (TAC-IR) may be considered for young patients or those with a colorectal cancer family history to prevent metachronous lesions and facilitate surveillance.

METHODS

All Ontario patients newly diagnosed with colon cancer over 12 months beginning in July 1997 were staged at the time of surgery. The extent of resection was compared with variables, including familial risk obtained from the Ontario Familial Colon Cancer Registry.

RESULTS

Complete staging was possible for 86% of patients. A total of 1223 patients had a potentially curative resection: 17%, 46%, and 36% were stage I, II, and III, respectively. Patients were more likely to receive a TAC-IR if they were < or = 50 years old (odds ratio [OR], 3.5; 95% confidence interval [CI], 1.8-6.6), if they had a synchronous lesion (OR, 28.37; 95% CI, 12.2-61.2), or if they were at a teaching hospital (OR, 2.8; 95% CI, 1.6-4.7), but not if they had a family history (OR,.7; 95% CI,.3- 1.5).

CONCLUSIONS

Young age, teaching hospital, and multiple cancers but not family history were important factors for performing a TAC-IR.