Gillian Crawford

Long-term effect of aspirin on cancer risk in carriers of hereditary colorectal cancer: an analysis from the CAPP2 randomised controlled trial

Summary Background Observational studies report reduced colorectal cancer in regular aspirin consumers. Randomised controlled trials have shown reduced risk of adenomas but none have employed prevention of colorectal cancer as a primary endpoint. The CAPP2 trial aimed to investigate the antineoplastic effects of aspirin and a resistant starch in carriers of Lynch syndrome, the major form of hereditary colorectal cancer; we now report long-term follow-up of participants randomly assigned to aspirin or placebo. Methods In the CAPP2 randomised trial, carriers of Lynch syndrome were randomly assigned in a two-by-two factorial design to 600 mg aspirin or aspirin placebo or 30 g resistant starch or starch placebo, for up to 4 years. Randomisation was in blocks of 16 with provision for optional single-agent randomisation and extended postintervention double-blind follow-up; participants and investigators were masked to treatment allocation. The primary endpoint was development of colorectal cancer. Analysis was by intention to treat and per protocol. This trial is registered, ISRCTN59521990. Results 861 participants were randomly assigned to aspirin or aspirin placebo. At a mean follow-up of 55·7 months, 48 participants had developed 53 primary colorectal cancers (18 of 427 randomly assigned to aspirin, 30 of 434 to aspirin placebo). Intention-to-treat analysis of time to first colorectal cancer showed a hazard ratio (HR) of 0·63 (95% CI 0·35–1·13, p=0·12). Poisson regression taking account of multiple primary events gave an incidence rate ratio (IRR) of 0·56 (95% CI 0·32–0·99, p=0·05). For participants completing 2 years of intervention (258 aspirin, 250 aspirin placebo), per-protocol analysis yielded an HR of 0·41 (0·19–0·86, p=0·02) and an IRR of 0·37 (0·18–0·78, p=0·008). No data for adverse events were available postintervention; during the intervention, adverse events did not differ between aspirin and placebo groups. Interpretation 600 mg aspirin per day for a mean of 25 months substantially reduced cancer incidence after 55·7 months in carriers of hereditary colorectal cancer. Further studies are needed to establish the optimum dose and duration of aspirin treatment. Funding European Union; Cancer Research UK; Bayer Corporation; National Starch and Chemical Co; UK Medical Research Council; Newcastle Hospitals trustees; Cancer Council of Victoria Australia; THRIPP South Africa; The Finnish Cancer Foundation; SIAK Switzerland; Bayer Pharma.

An investigation of patients’ motivations for their participation in genetics-related research

Design: Qualitative interview study. Participants: Fifty-nine patients with a family history of cancer who attend a regional cancer genetics clinic in the UK were interviewed about their current and previous research experiences. Findings: Interviewees gave a range of explanations for research participation. These were categorised as (a) social—research participation benefits the wider society by progressing science and improving treatment for everyone; (b) familial—research participation may improve healthcare and benefit current or future generations of the participant’s family; and (c) personal—research participation provides therapeutic or non-therapeutic benefits for oneself. Conclusions: We discuss the distinction drawn between motives for research participation focused upon self (personal) and others (familial/social), and observe that personal, social and familial motives can be seen as interdependent. For example, research participation that is undertaken to benefit others, particularly relatives, may also offer a number of personal benefits for self, such as enabling participants to feel that they have discharged their social or familial obligations. We argue for the need to move away from simple, static, individualised notions of research participation to a more complex, dynamic and inherently social account.

Long-term effect of resistant starch on cancer risk in carriers of hereditary colorectal cancer: an analysis from the CAPP2 randomised controlled trial.

BACKGROUND Observational studies report that higher intake of dietary fibre (a heterogeneous mix including non-starch polysaccharides and resistant starches) is associated with reduced risk of colorectal cancer, but no randomised trials with prevention of colorectal cancer as a primary endpoint have been done. We assessed the effect of resistant starch on the incidence of colorectal cancer. METHODS In the CAPP2 study, individuals with Lynch syndrome were randomly assigned in a two-by-two factorial design to receive 600 mg aspirin or aspirin placebo or 30 g resistant starch or starch placebo, for up to 4 years. Randomisation was done with a block size of 16. Post-intervention, patients entered into double-blind follow-up; participants and investigators were masked to treatment allocation. The primary endpoint for this analysis was development of colorectal cancer in participants randomly assigned to resistant starch or resistant-starch placebo with both intention-to-treat and per-protocol analyses. This study is registered, ISRCTN 59521990. FINDINGS 463 patients were randomly assigned to receive resistant starch and 455 to receive resistant-starch placebo. At a median follow-up 52·7 months (IQR 28·9-78·4), 53 participants developed 61 primary colorectal cancers (27 of 463 participants randomly assigned to resistant starch, 26 of 455 participants assigned to resistant-starch placebo). Intention-to-treat analysis of time to first colorectal cancer showed a hazard ratio (HR) of 1·40 (95% CI 0·78-2·56; p=0·26) and Poisson regression accounting for multiple primary events gave an incidence rate ratio (IRR) of 1·15 (95% CI 0·66-2·00; p=0·61). For those completing 2 years of intervention, per-protocol analysis yielded a HR of 1·09 (0·55-2·19, p=0·80) and an IRR of 0·98 (0·51-1·88, p=0·95). No information on adverse events was gathered during post-intervention follow-up. INTERPRETATION Resistant starch had no detectable effect on cancer development in carriers of hereditary colorectal cancer. Dietary supplementation with resistant starch does not emulate the apparently protective effect of diets rich in dietary fibre against colorectal cancer. FUNDING European Union, Cancer Research UK, Bayer Corporation, National Starch and Chemical Co, UK Medical Research Council, Newcastle Hospitals Trustees, Cancer Council of Victoria Australia, THRIPP South Africa, The Finnish Cancer Foundation, SIAK Switzerland, and Bayer Pharma.

Defining and managing incidental findings in genetic and genomic practice

The rapidly declining costs and increasing speeds of whole-genome analysis mean that genetic testing is undergoing a shift from targeted approaches to broader ones that look at the entire genome. As whole-genome technologies gain widespread use, questions about the management of so-called incidental findings—those unrelated to the question being asked—need urgent consideration. In this review, we bring together current understanding and arguments about (1) appropriate terminology, (2) the determination of clinical utility and when to disclose incidental findings, (3) the differences in management and disclosure in clinical, research and commercial contexts and (4) ethical and practical issues about familial implications and recontacting those tested. We recommend that greater international consensus is developed around the disclosure and management of incidental findings, with particular attention to when, and how, less clear-cut results should be communicated. We suggest that there is no single term that captures all the issues around these kinds of findings and that different terms may, therefore, need to be used in different settings. We also encourage the use of clear consent processes, but suggest that the absence of consent should not always preclude disclosure. Finally, we recommend further research to identify ways to implement the use of a genome output as a resource, accessible over time, to facilitate appropriate disclosure and recontact when the significance of a previously unclear incidental finding is clarified.

Genetic medicine and incidental findings: it is more complicated than deciding whether to disclose or not

Purpose:The aim of this study was to explore the clinical management of incidental findings. Advances in the speed and sensitivity of genetic technologies have not only improved the diagnostic rate but also result in an increase in unanticipated diagnoses. Recent debate on such “incidental findings” has considered whether or not to actively search for and, then, disclose incidental findings. In our experience, many incidental findings need to be investigated in family members before their clinical significance can be assessed. This adds complexity to the debate about disclosure.Methods:Using anonymized clinical examples, we illustrate the downstream implications when a result reveals an incidental abnormality of potential clinical significance that is not related to the reasons for doing the test.Results:Our examples illustrate that the determination of clinical significance may require participation of family members in both testing and surveillance.Conclusion:The need to investigate multiple relatives in order to decide whether or not a finding is clinically significant has implications for consent and disclosure practices. Communication with, and care for, relatives who have no reason to suspect particular diagnoses is a challenge for any health-care service. These costs also need to be taken into account as genetic testing enters mainstream medicine.Genet Med 15 11, 896–899.Genetics in Medicine (2013); 15 11, 896–899. doi:10.1038/gim.2013.165

Health-care professionals' responsibility to patients' relatives in genetic medicine: a systematic review and synthesis of empirical research.

Purpose:The extent of the responsibility of health-care professionals (HCPs) to ensure that patients’ relatives are told of their risk is unclear. Current international guidelines take confidentiality to the individual patient as the default position, but some suggest that disclosure could be default and genetic information could be conceptualized as familial.Methods:Our systematic review and synthesis of 17 studies explored the attitudes of HCPs, patients, and the public regarding the extent of HCPs’ responsibility to relatives with respect to disclosure.Results:Health-care professionals generally felt a responsibility to patients’ relatives but perceived a variety of reasons why it would be difficult to act on this responsibility. Public/patient views were more wide-ranging. Participants identified several competing and overlapping arguments for and against HCP disclosure: guidelines do not permit/mandate it, privacy, medical benefit, impact on family dynamics, quality of communication, and respecting autonomy.Conclusion:We argue that HCPs can sometimes share genetic information without breaching confidentiality and that they could factor into their considerations the potential harm to family dynamics of nondisclosure. However, we need more nuanced research about their responsibilities to relatives, particularly as genomic tests are used more frequently in clinical practice.Genet Med 18 4, 290–301.

Healthcare professionals’ and researchers’ understanding of cancer genetics activities: a qualitative interview study

Aims: To describe individuals’ perceptions of the activities that take place within the cancer genetics clinic, the relationships between these activities and how these relationships are sustained. Design: Qualitative interview study. Participants: Forty individuals involved in carrying out cancer genetics research in either a clinical (n = 28) or research-only (n = 12) capacity in the UK. Findings: Interviewees perceive research and clinical practice in the subspecialty of cancer genetics as interdependent. The boundary between research and clinical practice is described as vague or blurred, and this ambiguity is regarded as being sustained by a range of methodological, ethical and economic factors. The implications of these findings for the “therapeutic misconception” are explored. It is argued that while research participation is seen as having therapeutic benefit for individual patients, the interviewees are not labouring under any misconceptions about the relationship between research and clinical care. It is suggested that concepts such as the “therapeutic misconception” may have less relevance in highly technological specialities that are characterised by a developing evidence base.

First case report of Muir-Torre syndrome associated with non-small cell lung cancer.

The eponymous Muir–Torre syndrome (MTS) is a clinical variant of hereditary non polyposis colorectal cancer, and is defined as an autosomal dominant condition with simultaneous sebaceous neoplasms of the skin and visceral malignant disease resulting from germline mutations in the DNA mismatch repair (MMR) genes. To date the most common visceral malignancy described is colorectal cancer, which is seen in approximately 50% of cases. Other clearly associated tumours include endometrial adenocarcinomas, urothelial transitional cell carcinomas, upper gastrointestinal adenocarcinomas, sebaceous adenomas and ovarian (often mucinous) carcinomas. Here we report the first recorded case of adenocarcinoma of the lung with loss of MMR gene function to be identified in a patient with MTS. The MMR deficient lung tumour demonstrated less aggressive clinical behaviour compared with a synchronous MMR proficient lung adenocarcinoma.

A more fitting term in the incidental findings debate: one term does not fit all situations.

A more fitting term in the incidental findings debate: one term does not fit all situations

Rescue Obligations and Collective Approaches: Complexities in Genomics

We agree with Garrett (2015) that too hasty an application of a duty to rescue in a wide variety of cases should be questioned and that the “purported duty to regularly return incidental findings i...