Prevention of breast cancer in the context of a national breast screening programme

Breast cancer is not only increasing in the west but also particularly rapidly in eastern countries where traditionally the incidence has been low. The rise in incidence is mainly related to changes in reproductive patterns and lifestyle. These trends could potentially be reversed by defining women at greatest risk and offering appropriate preventive measures. A model for this approach was the establishment of Family History Clinics (FHCs), which have resulted in improved survival in younger women at high risk. New predictive models of risk that include reproductive and lifestyle factors, mammographic density and measurement of risk-associated single nucleotide polymorphisms (SNPs) may give more precise information concerning risk and enable better targeting for mammographic screening programmes and of preventive measures. Endocrine prevention using anti-oestrogens and aromatase inhibitors is effective, and observational studies suggest lifestyle modification may also be effective. However, referral to FHCs is opportunistic and predominantly includes younger women. A better approach for identifying older women at risk may be to use national breast screening programmes. Here were described pilot studies to assess whether the routine assessment of breast cancer risk is feasible within a population-based screening programme, whether the feedback and advice on risk-reducing interventions would be welcomed and taken up, and to consider whether the screening interval should be modified according to breast cancer risk.

BRCA1 testing should be offered to individuals with triple-negative breast cancer diagnosed below 50 years

BACKGROUND

Triple-negative (TN) tumours are the predominant breast cancer subtype in BRCA1 mutation carriers. Recently, it was proposed that all individuals below 50 years of age with TN breast cancer should be offered BRCA testing. We have evaluated the BRCA1 mutation frequency and the implications for clinical practice of undertaking genetic testing in women with TN breast cancer.

METHODS

We undertook BRCA1 mutation analysis in 308 individuals with TN breast cancer, 159 individuals from unselected series of breast cancer and 149 individuals from series ascertained on the basis of young age and/or family history.

RESULTS

BRCA1 mutations were present in 45 out of 308 individuals. Individuals with TN cancer <50 years had >10% likelihood of carrying a BRCA1 mutation in both the unselected (11 out of 58, 19%) and selected (26 out of 111, 23%) series. However, over a third would not have been offered testing using existing criteria. We estimate that testing all individuals with TN breast cancer <50 years would generate an extra 1200 tests annually in England.

CONCLUSION

Women with TN breast cancer diagnosed below 50 years have >10% likelihood of carrying a BRCA1 mutation and are therefore eligible for testing in most centres. However, implementation may place short-term logistical and financial burdens on genetic services.

Familial breast cancer: is it time to move from a reactive to a proactive role?

In 2004 the NICE guidelines on familial breast cancer advised Health Care Professionals that they should not actively seek to identify women with a family history of breast cancer. We have carried out a review of the evidence base and a large scale questionnaire survey of health professionals in four European countries. There is overwhelming support amongst GPs and surgeons against the premise that that health care professionals should not be proactive in identifying patients at risk of familial breast cancer. This that suggest the time is right to overturn the NICE decision.

Genetic testing and screening of individuals at risk of NF2

Genetic testing and management of the at-risk individual for neurofibromatosis type 2 (NF2) is complicated by the well-documented risk of mosaicism that causes a milder later onset more asymmetrical disease course. Risks of NF2 were derived from genetic testing of over 1000 individuals through the Manchester NF2-testing service. Individuals are at risk of NF2 or have 'potential' NF2 if they have features of the disease that fall short of diagnostic criteria or are the first-degree relative of someone with NF2 or suspected NF2. The present protocol devised for the Nationally Commissioned Group (NCG) NF2 service in England addresses the risks, genetic testing and screening protocol for individuals at risk of NF2. Screening with cranial magnetic resonance imaging is advised until the risk of NF2 falls below a pragmatic threshold of 1%. Multiple case scenarios are shown to illustrate how to use the protocol.

P3-09-02: Intermittent Dietary Carbohydrate Restriction Enables Weight Loss and Reduces Breast Cancer Risk Biomarkers

Background: Energy restriction is a potential strategy for breast cancer prevention but is difficult to achieve and maintain. We found that intermittent energy restriction (2 days strict dieting week) is comparable to the standard approach of moderate daily restriction for weight loss and marginally better for improving insulin sensitivity, but no easier to follow1. In this follow on study we wished to test whether 2 novel intermittent low carbohydrate/low energy diets were feasible and easier to follow than a standard daily energy restriction. Design: Randomised comparison of 3 dietary types over 4 months in 115 overweight or obese (mean body mass index 31.0 [±5.3 SD] kg/m2) women at increased risk of breast cancer (lifetime risk &gt; 1 in 6).

Diets:

1. A restricted low carbohydrate diet (RLCD): 650 kcal and &lt;50g carbohydrate / day for 2 days per week

2. Ad lib low carbohydrate diet (ALCD): &lt;50g / day for 2 days per week with other food types (e.g. protein) ad lib

3. A standard daily restricted Mediterranean diet (DRMD): ∼ 1500kcal/day for 7 days per week

Methods: Weight, anthropometrics, blood markers for breast cancer; insulin resistance, oxidative stress markers, leptin, adiponectin, lipids, inflammatory markers IGF-1 were assessed at baseline, 1, 3 and 4 months.

Results: 88/114 completed the study (77%, drop outs 6 RLCD, 8 ALCD 12 DRMD). Last observation carried forward analyses show both intermittent low carbohydrate diets were superior to standard daily restriction for reducing weight and body fat: mean (95% confidence interval [CI]) change in body fat for RLCD was −4.3 (−5.6 to −3.0) kg, for ALCD −4.1 (−5.2 to −3.1) kg vs. −2.4 (−3.4 to −1.2) kg for DRMD (P value for difference between groups = 0.02). The intermittent groups had greater improvement in insulin resistance: mean (95% CI) change for RLCD was −22 (−35 to −11) %, ALCD −14 (−27 to −5%) % vs. −4 (−16 to 9) % for DRMD (P = 0.02). Other biomarkers are being assayed currently.

Conclusion: Greater weight loss, fewer drop outs and greater reductions in insulin resistance with the novel intermittent low carbohydrate diets indicate that these are alternative approaches for energy restriction for potentially reducing risk of breast cancer and other diseases.

Reference:

1Harvie MN, Pegington M, Mattson MP, Frystyk J, Dillon B, Evans G et al. The effects of intermittent or continuous energy restriction on weight loss and metabolic disease risk markers: a randomized trial in young overweight women. Int.J Obes (Lond) 35; 714–27, 2011. This study is funded by the Genesis Breast Cancer Prevention Appeal: www.genesisuk.org

Citation Information: Cancer Res 2011;71(24 Suppl):Abstract nr P3-09-02.

Menopausal symptoms and bone health in women undertaking risk reducing bilateral salpingo-oophorectomy: significant bone health issues in those not taking HRT

BACKGROUND

Women at high ovarian cancer risk, especially those with mutations in BRCA1/BRCA2, are encouraged to undergo bilateral risk-reducing salpingo-oophorectomy (BRRSPO) prior to the natural menopause. The decision to use HRT to cover the period of oestrogen deprivation up to 50 years of age is difficult because of balancing the considerations of breast cancer risk, bone and cardiovascular health.

METHODS

We reviewed by questionnaire 289 women after BRRSPO aged ≤48 years because of high ovarian cancer risk; 212 (73%) of women responded.

RESULTS

Previous HRT users (n=67) had significantly worse endocrine symptom scores than 67 current users (P=0.006). A total of 123 (58%) of women had ≥24 months of oestrogen deprivation <50 years with 78 (37%) never taking HRT. Bone density (DXA) evaluations were available on 119 (56%) women: bone loss with a T score of ≤-1.0 was present in 5 out of 31 (16%) women with no period of oestrogen deprivation <50 years compared with 37 out of 78 (47%) of those with ≥24 months of oestrogen deprivation (P=0.03).

INTERPRETATION

Women undergoing BRRSPO <50 years should be counselled concerning the risks/benefits of HRT, taking into consideration the benefits on symptoms, bone health and cardiovascular health, and that the risks of breast cancer from oestrogen-only HRT appear to be relatively small.

Evaluation of the XRCC1 gene as a phenotypic modifier in BRCA1/2 mutation carriers. Results from the consortium of investigators of modifiers of BRCA1/BRCA2

BACKGROUND

Single-nucleotide polymorphisms (SNPs) in genes involved in DNA repair are good candidates to be tested as phenotypic modifiers for carriers of mutations in the high-risk susceptibility genes BRCA1 and BRCA2. The base excision repair (BER) pathway could be particularly interesting given the relation of synthetic lethality that exists between one of the components of the pathway, PARP1, and both BRCA1 and BRCA2. In this study, we have evaluated the XRCC1 gene that participates in the BER pathway, as phenotypic modifier of BRCA1 and BRCA2.

METHODS

Three common SNPs in the gene, c.-77C>T (rs3213245) p.Arg280His (rs25489) and p.Gln399Arg (rs25487) were analysed in a series of 701 BRCA1 and 576 BRCA2 mutation carriers.

RESULTS

An association was observed between p.Arg280His-rs25489 and breast cancer risk for BRCA2 mutation carriers, with rare homozygotes at increased risk relative to common homozygotes (hazard ratio: 22.3, 95% confidence interval: 14.3-34, P<0.001). This association was further tested in a second series of 4480 BRCA1 and 3016 BRCA2 mutation carriers from the Consortium of Investigators of Modifiers of BRCA1 and BRCA2.

CONCLUSIONS AND INTERPRETATION

No evidence of association was found when the larger series was analysed which lead us to conclude that none of the three SNPs are significant modifiers of breast cancer risk for mutation carriers.

RASSF1A polymorphism in familial breast cancer

Inactivation or loss of the tumour suppressor Ras associated domain family 1 isoform A (RASSF1A) allele has been described in breast cancer. Recently, a missense polymorphism predicting p.A331S in RASSF1A was associated with an increased risk of breast cancer and early-onset breast cancer in BRCA1 and BRCA2 mutation carriers. We genotyped p.A331S RASSF1A in 854 independent, familial, white breast cancer patients (645 BRCA mutation negative, 119 BRCA1 and 90 BRCA2 positive) and compared the genotype in 331 healthy women. The RASSF1A p.A331S variant was not more common in the familial breast cancer cases than in the controls (P = 0.27). Subset analysis demonstrated no association in the BRCA1 (P = 0.26), BRCA2 (P = 0.16) or BRCA negative (P = 0.30) samples. Hence, the RASSF1A p.A331S polymorphism is not confirmed as a significant germline contributor to familial breast cancer susceptibility.

Targeted prostate cancer screening in men with mutations in BRCA1 and BRCA2 detects aggressive prostate cancer: preliminary analysis of the results of the IMPACT study

OBJECTIVE

To evaluate the role of targeted prostate cancer screening in men with BRCA1 or BRCA2 mutations, an international study, IMPACT (Identification of Men with a genetic predisposition to ProstAte Cancer: Targeted screening in BRCA1/2 mutation carriers and controls), was established. This is the first multicentre screening study targeted at men with a known genetic predisposition to prostate cancer. A preliminary analysis of the data is reported.

PATIENTS AND METHODS

Men aged 40-69 years from families with BRCA1 or BRCA2 mutations were offered annual prostate specific antigen (PSA) testing, and those with PSA > 3 ng/mL, were offered a prostate biopsy. Controls were men age-matched (± 5 years) who were negative for the familial mutation.

RESULTS

In total, 300 men were recruited (205 mutation carriers; 89 BRCA1, 116 BRCA2 and 95 controls) over 33 months. At the baseline screen (year 1), 7.0% (21/300) underwent a prostate biopsy. Prostate cancer was diagnosed in ten individuals, a prevalence of 3.3%. The positive predictive value of PSA screening in this cohort was 47·6% (10/21). One prostate cancer was diagnosed at year 2. Of the 11 prostate cancers diagnosed, nine were in mutation carriers, two in controls, and eight were clinically significant.

CONCLUSIONS

The present study shows that the positive predictive value of PSA screening in BRCA mutation carriers is high and that screening detects clinically significant prostate cancer. These results support the rationale for continued screening in such men.

Rates of loss of heterozygosity and mitotic recombination in NF2 schwannomas, sporadic vestibular schwannomas and schwannomatosis schwannomas

Biallelic inactivation of the NF2 gene occurs in the majority of schwannomas. This usually involves a combination of a point mutation or multiexon deletion, in conjunction with either a second point mutation or loss of heterozygosity (LOH). We have performed DNA sequence and dosage analysis of the NF2 gene in a panel of 239 schwannoma tumours: 97 neurofibromatosis type 2 (NF2)-related schwannomas, 104 sporadic vestibular schwannomas (VS) and 38 schwannomatosis-related schwannomas. In total, we identified germline NF2 mutations in 86 out of 97 (89%) NF2 patients and a second mutational event in 77 out of 97 (79%). LOH was by far the most common form of second hit. A combination of microsatellite analysis with either conventional comparative genomic hybridization (CGH) or multiplex ligation-dependent probe amplification (MLPA) identified mitotic recombination (MR) as the cause of LOH in 14 out of 72 (19%) total evaluable tumours. Among sporadic VS, at least one NF2 mutation was identified by sequence analysis or MLPA in 65 out of 98 (66%) tumours. LOH occurred in 54 out of 96 (56%) evaluable tumours, but MR only accounted for 5 out of 77 (6%) tested. LOH was present in 28 out of 34 (82%) schwannomatosis-related schwannomas. In all eight patients who had previously tested positive for a germline SMARCB1 mutation, this involved loss of the whole, or part of the long arm, of chromosome 22. In contrast, 5 out of 22 (23%) tumours from patients with no germline SMARCB1 mutation exhibited MR. High-resolution Affymetrix SNP6 genotyping and copy number (CN) analysis (Affymetrix, Santa Clara, CA, USA) were used to determine the chromosomal breakpoint locations in tumours with MR. A range of unique recombination sites, spanning approximately 11.4 Mb, were identified. This study shows that MR is a mechanism of LOH in NF2 and SMARCB1-negative schwannomatosis-related schwannomas, occurring less frequently in sporadic VS. We found no evidence of MR in SMARCB1-positive schwannomatosis, suggesting that susceptibility to MR varies according to the disease context.

Polymyxin B-Induced Release of Low-Molecular-Weight, Heat-Labile Enterotoxin from Escherichia coli

Polymyxin B-induced release of enterotoxin from Escherichia coli strain H-10407 was demonstrated. Incubation of E. coli cells derived from 6-h cultures with polymyxin caused the rapid release of enterotoxin with a molecular weight of approximately 20,000, as estimated by the gel filtration technique. The rapidity of the release of enterotoxin indicates that it probably resides in the periplasmic space of the cell. The low-molecular-weight enterotoxin possessed vascular permeability factor and diarrheagenic activities, both of which were found to be heat-labile. The permeability factor activity of this enterotoxin was neutralized by antisera prepared against crude E. coli enterotoxin, Vibrio cholerae enterotoxin (choleragen), and V. cholerae toxoid (choleragenoid), respectively. Supernatant fluids of 6-h E. coli cultures did not contain this molecular form of enterotoxin but did contain very high-molecular-weight, heat-labile enterotoxin. Incubation of cells derived from older (18 h) cultures with polymyxin caused the release of both low- (20,000) and high-molecular-weight forms of enterotoxin. We concluded that either the 20,000-dalton form of heat-labile enterotoxin is not released by E. coli under in vitro growth conditions or that enterotoxin released in this form is rapidly destroyed or inactivated.

SMARCB1 mutations are not a common cause of multiple meningiomas

BACKGROUND

Schwannomas and meningiomas are both part of the tumour spectrum of neurofibromatosis type 2 (NF2) and are associated with somatic loss of chromosome 22. They are also found commonly within the general population, unrelated to NF2. Germline SMARCB1 mutations have recently been identified as a pathogenic cause of a subset of familial schwannomatosis cases, and SMARCB1 is a candidate gene for causation of both schwannomas and meningiomas. Recently, Bacci et al reported a germline SMARCB1 mutation associated with familial schwannomatosis and multiple meningiomas. They concluded that SMARCB1 mutations can predispose to multiple meningiomas.

METHODS

We screened the SMARCB1 gene in a panel of 47 patients with multiple meningioma unrelated to NF2.

RESULTS

We found no germline mutations.

CONCLUSION

We conclude that while meningiomas may be associated with the schwannomatosis phenotype, SMARCB1 is not a major contributor to multiple meningioma disease.

Outcome from surgery for vestibular schwannomas in children

OBJECT

A review of sporadic and NF2-related vestibular schwannoma surgery in children (under 18 years of age) with a specific interest in resection rates, recurrence, facial nerve outcomes, hearing preservation, hearing rehabilitation and genetic analysis.

METHODS

A retrospective analysis of prospectively collected data of 35 consecutively operated vestibular schwannomas in 29 paediatric patients that underwent 38 operations between 1992 and 2007. Pre- and post-operative radiology, facial nerve function, pure tone audiogram and speech discrimination tests were performed with a mean follow-up of 4.5 years. Tumour and blood mutations were analysed in 86% of patients.

RESULTS

Total resection was achieved in all sporadic cases and 68% of NF2 cases. Near total resection led to tumour recurrence in 5 out of 10 cases. The facial nerve was anatomically preserved in 92%. Facial nerve function was excellent to good (Grades 1-3) in 88% with outcome related to tumour size. Hearing preservation was successful in 3 of 11 cases.

CONCLUSIONS

Surgery with complete resection results in excellent tumour control, but it is more difficult to attain total resection in NF2 with a relatively high recurrence rate of persistently growing tumours. A better facial outcome is associated with smaller tumours, near-total resection and first time surgery. Hearing preservation is possible in a minority. Hearing rehabilitation can be successful by utilising cochlear implants and auditory brain stem implants (ABI) as appropriate. Overall there is a low complication rate and results are comparable with adult series.

Further genotype--phenotype correlations in neurofibromatosis 2

Neurofibromatosis 2 (NF2) is caused by mutations in the NF2 gene predisposing carriers to develop nervous system tumours. Different NF2 mutations result in either loss/reduced protein function or gain of protein function (abnormally behaving mutant allele i.e. truncated protein potentially causing dominant negative effect). We present a comparison between the clinical presentations of patients with mutations that are predicted to produce truncated protein (nonsense/frameshift mutations) to those that results in loss of protein expression (large deletions) to elucidate further genotype-phenotype correlations in NF2. Patients with nonsense/frameshift mutations have a younger age of diagnosis and a higher prevalence/proportion of meningiomas (p = 0.002, p = 0.014), spinal tumours (p = 0.004, p = 0.004) and non-VIII cranial nerve tumours (p = 0.006, p = 0.003). We also found younger age of diagnosis of vestibular schwannomas (p = 0.007), higher mean numbers of cutaneous lesions (p = 0.003) and spinal tumours (p = 0.006) in these patients. With respect to NF2 symptoms, we found younger age of onset of hearing loss (p = 0.010), tinnitus (p = 0.002), paraesthesiae (p = 0.073), wasting and weakness (p = 0.001) and headaches (p = 0.049) in patients with nonsense/frameshift mutations. Our comparison shows, additional, new correlations between mutations in the NF2 gene and the NF2 disease phenotype, and this further confirms that nonsense/frameshift mutations are associated with more severe NF2 symptoms. Therefore patients with this class of NF2 mutation should be followed up closely.

Evaluation of a candidate breast cancer associated SNP in ERCC4 as a risk modifier in BRCA1 and BRCA2 mutation carriers. Results from the Consortium of Investigators of Modifiers of BRCA1/BRCA2 (CIMBA)

Background:

In this study we aimed to evaluate the role of a SNP in intron 1 of the ERCC4 gene (rs744154), previously reported to be associated with a reduced risk of breast cancer in the general population, as a breast cancer risk modifier in BRCA1 and BRCA2 mutation carriers.

Methods:

We have genotyped rs744154 in 9408 BRCA1 and 5632 BRCA2 mutation carriers from the Consortium of Investigators of Modifiers of BRCA1/2 (CIMBA) and assessed its association with breast cancer risk using a retrospective weighted cohort approach.

Results:

We found no evidence of association with breast cancer risk for BRCA1 (per-allele HR: 0.98, 95% CI: 0.93–1.04, P=0.5) or BRCA2 (per-allele HR: 0.97, 95% CI: 0.89–1.06, P=0.5) mutation carriers.

Conclusion:

This SNP is not a significant modifier of breast cancer risk for mutation carriers, though weak associations cannot be ruled out.

The TP53 Arg72Pro and MDM2 309G>T polymorphisms are not associated with breast cancer risk in BRCA1 and BRCA2 mutation carriers

Background:

The TP53 pathway, in which TP53 and its negative regulator MDM2 are the central elements, has an important role in carcinogenesis, particularly in BRCA1- and BRCA2-mediated carcinogenesis. A single nucleotide polymorphism (SNP) in the promoter region of MDM2 (309T>G, rs2279744) and a coding SNP of TP53 (Arg72Pro, rs1042522) have been shown to be of functional significance.

Methods:

To investigate whether these SNPs modify breast cancer risk for BRCA1 and BRCA2 mutation carriers, we pooled genotype data on the TP53 Arg72Pro SNP in 7011 mutation carriers and on the MDM2 309T>G SNP in 2222 mutation carriers from the Consortium of Investigators of Modifiers of BRCA1/2 (CIMBA). Data were analysed using a Cox proportional hazards model within a retrospective likelihood framework.

Results:

No association was found between these SNPs and breast cancer risk for BRCA1 (TP53: per-allele hazard ratio (HR)=1.01, 95% confidence interval (CI): 0.93–1.10, P_trend=0.77; MDM2: HR=0.96, 95%CI: 0.84–1.09, P_trend=0.54) or for BRCA2 mutation carriers (TP53: HR=0.99, 95%CI: 0.87–1.12, P_trend=0.83; MDM2: HR=0.98, 95%CI: 0.80–1.21, P_trend=0.88). We also evaluated the potential combined effects of both SNPs on breast cancer risk, however, none of their combined genotypes showed any evidence of association.

Conclusion:

There was no evidence that TP53 Arg72Pro or MDM2 309T>G, either singly or in combination, influence breast cancer risk in BRCA1 or BRCA2 mutation carriers.

Childhood predictive genetic testing for Li-Fraumeni syndrome

Presymptomatic genetic testing in childhood for adult onset conditions is generally discouraged as it does not directly benefit the child and removes their autonomy. In certain cancer prone conditions such as Familial Adenomatous Polyposis and Von Hippel Lindau disease there are risks of disease in childhood and benefit to children not inheriting a mutation in being able to forego unpleasant screening tests. Li-Fraumeni syndrome caused by constitutional TP53 mutations there are also implications in childhood with a risk of around 20% of a childhood malignancy. However, as yet no evidence based surveillance programme has been identified. We describe our experience of childhood testing for four children in two Li-Fraumeni families caused by TP53 mutations.

Cumulative lifetime incidence of extracolonic cancers in Lynch syndrome: a report of 121 families with proven mutations

Lynch syndrome or hereditary non-polyposis colorectal cancer is caused by mutations of DNA mismatch repair (MMR) genes. The extracolonic tumour spectrum includes endometrial, ovarian, gastric, small bowel, pancreatic, hepatobiliary, brain, and urothelial neoplasms. Families were referred on the basis of clinical criteria. Tumour immunohistochemistry and microsatellite testing were performed. Appropriate patients underwent sequencing of relevant exons of the MMR genes. Proven and obligate mutation carriers and first-degree relatives (FDRs) with a Lynch syndrome spectrum cancer were considered mutation carriers, as were a proportion of untested, unaffected FDRs based on the proportion of unaffected relatives testing positive in each age group. Kaplan-Meier analysis of risk to 70 years was calculated. One hundred and eighty-four Lynch syndrome spectrum extracolonic cancers in 839 proven, obligate, or assumed mutation carriers were analysed. Cumulative risk for females of an extracolonic tumour is 47.4% (95% CI 43.9-50.8). The risk to males is 26.5% (95% CI 22.6-30.4). There was no reduction in gynaecological malignancies due to gynaecological screening (examination, transvaginal ultrasound scan, hysteroscopy and endometrial biopsy). Males have a higher risk of gastric cancer than females (p = 0.0003). Gastric cancer risk in those born after 1935 does not justify surveillance. These penetrance estimates have been corrected for ascertainment bias and are appropriate for those referred to a high-risk clinic.

Use of assistive technology by students with dyslexia in post-secondary education

PURPOSE

To identify the types and mix of technology (hardware and software) provided to post-secondary students with dyslexia under the UK's Disabled Student Allowance (DSA), and to determine the students' satisfaction with, and use of, the equipment provided and to examine their experiences with training.

METHOD

A telephone survey of 455 students with dyslexia who had received technology under the DSA from one equipment supplier was conducted over in the period September to December 2005. The survey obtained a mixture of quantitative data (responses to binary questions and selections from a five-point rating scale) and qualitative data (participants identifying positive and negative experiences with technology). In addition, the equipment supplier's database was used to determine the technology supplied to each of the participants.

RESULT

Technology provision is variable between students. The majority of students receive a recording device, text-to-speech software and concept mapping tools in addition to a standard computer system. Ninety percent of participants are satisfied or very satisfied with the hardware and the software that they receive. A total of 48.6% of participants received training, with 86.3% of those expressing satisfaction with the training they received. Of those that were offered training but elected not to receive it, the majority did so because they felt confident about their IT skills.

CONCLUSIONS

Students express satisfaction not only with the computer systems that they receive but also with the special-purpose software provided to support their studies. Significant numbers of students elect not to receive training and may, therefore, not be using their equipment to its best advantage.

Inherited predisposition to colorectal adenomas caused by multiple rare alleles of MUTYH but not OGG1, NUDT1, NTH1 or NEIL 1, 2 or 3

BACKGROUND

MUTYH-associated polyposis (MAP) is a recessive trait characterised by multiple colorectal adenomas and a high risk of colorectal cancer. MUTYH functions in the DNA base excision repair pathway and has a key role in the repair of oxidative DNA damage.

OBJECTIVES

To assess the contribution of inherited variants in genes involved in base excision repair and oxidative DNA damage including MUTYH, OGG1, NEIL1, NEIL2, NEIL3, NUDT1 and NTH1 to the multiple colorectal adenoma phenotype.

METHODS

Inherited variants of MUTYH, OGG1, NEIL1, NEIL2, NEIL3, NUDT1 and NTH1 were sought in 167 unrelated patients with multiple colorectal adenomas whose family histories were consistent with recessive inheritance. These variants were also characterised in approximately 300 population controls.

RESULTS

Thirty-three patients (20%) and no controls were MUTYH homozygotes or compound heterozygotes (ie, carried two mutations) and therefore had MAP. Eight different pathogenic MUTYH mutations were identified, of which four were novel. MAP cases had significantly more adenomas than non-MAP cases (p = 0.0009; exact test for trends in proportions) and presented earlier (p = 0.013; analysis of variance). Twenty-four protein-altering variants were identified upon screening of OGG1, NEIL1, NEIL2, NEIL3, NUDT1 and NTH1. However, all combinations of two (or more) variants that were identified at an individual locus in patients were also seen in controls, and no variants were significantly over-represented (or under-represented) in cases.

CONCLUSION

Multiple rare alleles of MUTYH are associated with autosomal recessive MAP, while OGG1, NEIL1, NEIL2, NEIL3, NUDT1 and NTH1 do not contribute significantly to autosomal recessive polyposis.

Colorectal cancer in HNPCC: cumulative lifetime incidence, survival and tumour distribution. A report of 121 families with proven mutations

Hereditary non-polyposis colorectal cancer (HNPCC) is an autosomal dominant condition caused by inactivating mutations of DNA mismatch repair (MMR) genes. An accurate estimation of colorectal cancer risk for mutation carriers is essential for counselling and rationalizing screening programmes. Families were referred on the basis of clinical criteria. Tumour immunohistochemistry and microsatellite testing were performed. Appropriate patients underwent sequencing of all relevant exons of the MMR genes. Proven and obligate mutation carriers and first-degree relatives (FDRs) with an HNPCC spectrum cancer were considered mutation carriers, as were a proportion of untested, unaffected FDRs based on the proportion of unaffected relatives testing positive in each age group. The cumulative lifetime risk was calculated by Kaplan-Meier analysis. Three hundred and forty-one colorectal cancers in 839 proven, obligate, or assumed mutation carriers were analysed. The cumulative risk to age 70 years for all mutation carriers combined was 50.4% (95% CI 47.8-52.9). The cumulative risk in males was 54.3% (95% CI 50.7-57.8), which was significantly higher than in females (log rank p = 0.02) who had a risk of 46.3% (95% CI 42.8-49.9). These penetrance estimates from HNPCC families attending high-risk clinics have been corrected for ascertainment bias and are appropriate risks for those referred to a high-risk clinic. Current colonoscopic screening guidelines are appropriate.