Testing for causality between systematically identified risk factors and glioma: a Mendelian randomization study.

BACKGROUND: Whilst epidemiological studies have provided evidence of associations between certain risk factors and glioma onset, inferring causality has proven challenging. Using Mendelian randomization (MR), we assessed whether associations of 36 reported glioma risk factors showed evidence of a causal relationship. METHODS: We performed a systematic search of MEDLINE from inception to October 2018 to identify candidate risk factors and conducted a meta-analysis of two glioma genome-wide association studies (5739 cases and 5501 controls) to form our exposure and outcome datasets. MR analyses were performed using genetic variants to proxy for candidate risk factors. We investigated whether risk factors differed by subtype diagnosis (either glioblastoma (n = 3112) or non-glioblastoma (n = 2411)). MR estimates for each risk factor were determined using multiplicative random effects inverse-variance weighting (IVW). Sensitivity analyses investigated potential pleiotropy using MR-Egger regression, the weighted median estimator, and the mode-based estimator. To increase power, trait-specific polygenic risk scores were used to test the association of a genetically predicated increase in each risk factor with glioma onset. RESULTS: Our systematic search identified 36 risk factors that could be proxied using genetic variants. Using MR, we found evidence that four genetically predicted traits increased risk of glioma, glioblastoma or non-glioblastoma: longer leukocyte telomere length, liability to allergic disease, increased alcohol consumption and liability to childhood extreme obesity (> 3 standard deviations from the mean). Two traits decreased risk of non-glioblastoma cancers: increased low-density lipoprotein cholesterol (LDLc) and triglyceride levels. Our findings were similar across sensitivity analyses that made allowance for pleiotropy (genetic confounding). CONCLUSIONS: Our comprehensive investigation provides evidence of a causal link between both genetically predicted leukocyte telomere length, allergic disease, alcohol consumption, childhood extreme obesity, and LDLc and triglyceride levels, and glioma. The findings from our study warrant further research to uncover mechanisms that implicate these traits in glioma onset.

Genome-wide association study identifies variants associated with hair length in Brangus cattle.

Thermal stress limits beef cattle production and a shorter hair coat is a key thermoregulative adaptation that allows cattle to lose heat more efficiently. The objective of this study was to identify genetic variants associated with the length of the undercoat and topcoat of cattle utilizing 1456 Brangus heifers genotyped with the Bovine GGP F250 array. Seven SNPs in the PCCA gene were significantly associated with undercoat length. PCCA belongs to the biotin transport and metabolism pathway. Biotin deficiency has been reported to cause hair loss. Four SNPs in an 110 kb including a missense mutation in the PRLR gene were significantly associated with topcoat length. Whereas the association of this polymorphism with hair length is novel, the SLICK mutation in PRLR has previously been demonstrated to significantly impact hair length in cattle. These newly detected genetic variants may contribute to a shorter hair coat and more thermotolerant animals.

Early participant-reported symptoms as predictors of adherence to anastrozole in the International Breast Cancer Intervention Studies II.

Background: Anastrozole reduces breast cancer risk in women at high risk, but implementing preventive therapy in clinical practice is difficult. Here, we evaluate adherence to anastrozole in the International Breast Cancer Intervention Study (IBIS)-II prevention and ductal carcinoma in situ (DCIS) trials, and its association with early symptoms. Patients and methods: In the prevention trial, 3864 postmenopausal women were randomized to placebo versus anastrozole. A total of 2980 postmenopausal women with DCIS were randomized to tamoxifen versus anastrozole. Adherence to trial medication was calculated using the Kaplan-Meier method and all P-values were two-sided. Results: In the prevention trial, adherence was 65.8% [anastrozole (65.7%) versus placebo (65.9%); HR = 0.97 (0.87-1.09), P = 0.6]. Adherence was lower for those reporting arthralgia in the placebo group (P = 0.02) or gynecological symptoms in the anastrozole group (P = 0.003), compared with those not reporting these symptoms at 6 months. In the DCIS study, adherence was 66.7% [anastrozole (67.5%) versus tamoxifen (65.8%); HR = 1.06 (0.94-1.20), P = 0.4]. Hot flashes were associated with greater adherence in the anastrozole arm (P = 0.02). In both studies, symptoms were mostly mild or moderately severe, and adherence decreased with increasing severity for most symptoms. Drop-outs were highest in the first 1.5 years of therapy in both trials. Conclusions: In the IBIS-II prevention and DCIS trials, over two-thirds of women were adherent to therapy, with no differences by treatment groups. Participants who reported specific symptoms in the IBIS-II prevention trial had a small but significant effect on adherence, which strengthened as severity increased. Strategies to promote adherence should target the first year of preventive therapy.

Young age at first pregnancy does protect against early onset breast cancer in BRCA1 and BRCA2 mutation carriers.

PURPOSE: Previous research assessing the impact of pregnancy and age at first pregnancy on breast cancer risk in BRCA1 and BRCA2 mutation carriers has produced conflicting results, with some studies showing an increased risk following early first pregnancy in contrast to the reduced risk in the general population of women. The present study addresses these inconsistencies. METHODS: Female BRCA1 and BRCA2 carriers from North West England were assessed for breast cancer incidence prior to 50 years of age comparing those with an early first full-term pregnancy (< 21 years) to those without a full-term pregnancy. Breast cancer incidence per decade from 20 years and Kaplan-Meier analyses were performed. RESULTS: 2424 female mutation carriers (1278 BRCA1; 1146 BRCA2) developed 990 breast cancers under the age of 50 years. Women who had their first term pregnancy prior to age 21 (n = 441) had a lower cancer incidence especially between age 30-39 years. Kaplan-Meier analysis showed an odds ratio of 0.78 for BRCA1 (p = 0.005) and 0.73 for BRCA2 (p = 0.002). CONCLUSIONS: The present study demonstrates a clear protective effect of early first pregnancy on breast cancer risk in both BRCA1 and BRCA2 mutation carriers.

'For me it's about not feeling like I'm on a diet': a thematic analysis of women's experiences of an intermittent energy restricted diet to reduce breast cancer risk.

BACKGROUND: Weight-loss programmes requiring intermittent energy restriction offer an alternative to continuous energy restriction programmes that typically have low adherence. We reported greater weight loss, better adherence and spontaneous reduced energy intake on healthy eating days with intermittent as opposed to continuous energy restriction. The present study aims to explore why intermittent energy restriction diets exert these positive effects. METHODS: Semi-structured interviews were carried out with 13 women aged 39-62 years, who followed a 4-month intermittent energy restriction (2 days of low energy/low carbohydrate, 5 days of healthy eating). Nine of the 13 women successfully lost >5% of their total body weight. Data were analysed using thematic analysis. RESULTS: The intermittent regimen redefined the meaning of dieting and normal eating. Women reconceptualised dieting as only two low energy days per week, even though this often differed from their pre-diet eating patterns. Women reported that they could adhere more closely to the rules of the intermittent diet compared to previously attempted continuous diets. They found that the intermittent diet was less cognitively demanding because the restrictive and clear rules of the intermittent diet were easier to understand and easier to follow than with continuous dieting. CONCLUSIONS: Many participants found intermittent dieting preferable to previous experiences of continuous dieting. The findings provide some insight into the ways in which intermittent dieting is successful, and why it could be considered a viable alternative to continuous energy restriction for weight loss.

False-negative MRI breast screening in high-risk women.

AIM: To determine the frequency of and reasons for false-negative breast magnetic resonance imaging (MRI) examinations in high-risk women undergoing annual screening. MATERIALS AND METHODS: The family history clinic database was interrogated and women at high risk of breast cancer who had undergone screening MRI and been diagnosed with breast cancer within 2 years of the MRI examination were identified. All available MRI examinations were reviewed and classified by two radiologists. RESULTS: Of 32 women diagnosed with breast cancer, 23 had MRI images available for review. Fourteen were diagnosed at MRI, four at interim mammography, two symptomatically, one incidentally on ultrasound, and two at risk-reducing mastectomy. Ten women (43%) had potentially avoidable delays in diagnosis. The preceding MRIs were classified as false-negative screens in five women (one prevalent, four incident), false-negative assessment in seven and minimal signs in three (three women were assigned dual classifications). Common reasons for diagnostic delay included small enhancing masses that were overlooked, areas of non-mass enhancement that showed little or no change between screens, false reassurance from normal conventional imaging at assessment, and overreliance on short-interval repeat MRI. CONCLUSION: Small enhancing foci, masses, and areas of segmental non-mass enhancement are common MRI features of early breast cancer. Lack of change of non-mass enhancement on serial examinations does not exclude malignancy. Double reading of both screening and assessment examinations is recommended. Ready access to MRI biopsy is essential. Short-interval repeat MRI should be limited to reassessing low suspicion areas likely to be benign glandular enhancement. Annual mammography remains important in these women.

Low prevalence of HER2 positivity amongst BRCA1 and BRCA2 mutation carriers and in primary BRCA screens.

The aim of this study is to delineate more clearly the prevalence of HER2+ breast cancer in women with germline BRCA1/2 mutations. For this purpose, we analysed primary mutation screens on women with breast cancer with unequivocal HER2 amplification and assessed the proportion of BRCA1 and BRCA2 breast cancers that were HER2+ comparing this with the existing literature. The results are that 1063 primary BRCA screens had confirmed tumour HER2 status. If HER2+ only 2.5 % (4/156) and 3.2 % (5/156) of women had a BRCA1 or BRCA2 mutation identified respectively; compared to 27.7 % (115/415) and 8.2 % (34/415) with triple negative tumours. Only 2.1 % (4/195) women with BRCA1-related breast cancer had HER2 amplified breast cancers rising to 6.8 % (n = 12, p = 0.04) in BRCA2. These rates are in keeping with most of the existing literature except a recent large multicenter report which documented higher rates but with no control group. The study concluded that true HER2-amplified breast cancers are rare amongst BRCA1 mutation carriers and are less common in BRCA2 than background rates.

Intensive breast screening in BRCA2 mutation carriers is associated with reduced breast cancer specific and all cause mortality.

BACKGROUND: The addition of annual MRI screening to mammography has heightened optimism that intensive screening along with improved treatments may substantially improve life expectancy of women at high risk of breast cancer. However, survival data from BRCA2 mutation carriers undergoing intensive combined breast screening are scarce. METHODS: We have collated the results of screening with either annual mammography or mammography with MRI in female BRCA2 mutation carriers in Manchester and Oslo and use a Manchester control group of BRCA2 mutation carriers who had their first breast cancer diagnosed without intensive screening. RESULTS: Eighty-seven BRCA2 mutation carriers had undergone combined (n = 34) or mammography (n = 53) screening compared to 274 without such intensive screening. Ten year breast cancer specific survival was 100 % in the combined group (95 % CI 82.5-100 %) and 85.5 % (95 % CI 72.6-98.4 %) in the mammography group compared to 74.6 % (95 % CI 66.6-82.6 %) in the control group. Better survival was driven by lymph node status (negative in 67 % of screened vs 39 % of unscreened women; p < 0.001) and a significantly greater proportion of intensively screened women had invasive breast cancers <2 cm at diagnosis (74.6 % vs 50.4 %; p = 0.002). CONCLUSION: Intensive combined breast cancer screening with annual MRI and mammography appears to improve survival from breast cancer in BRCA2 mutation carriers. Data from larger groups are required to confirm the effectiveness of combined screening in BRCA2 carriers.

Development and validation of a symptom-based severity score for haemorrhoidal disease: the Sodergren score.

AIM: One major obstacle in assessing the efficacy of treatment of haemorrhoids and the comparison of trials has been the lack of a standardized, validated symptom severity score. This study aimed to develop an objective, validated symptom-based score of severity for haemorrhoids that can be used to compare treatments, monitor disease and assist in surgical decisions. METHOD: A symptom and quality-of-life questionnaire was developed from the literature in conjunction with expert surgical opinion. The questionnaire was circulated to patients with confirmed haemorrhoids. A statistical model was used to derive a weighted score of symptoms most affecting patients' quality of life. Patients who were offered operative treatment were independently judged by specialists to have more severe symptoms, with further validation of the scoring system against treatment. RESULTS: Forty-five patients were included in final validation analysis, of whom 44 (98%) reported multiple symptoms, the most common being rectal bleeding. Patient-reported effects on quality of life were 47.5 ± 36.3 (1-100 visual analogue scale). Calculated symptom severity scores were used to compare patients receiving operative or ambulatory care, with significant difference in the scores (7.7 ± 3.9 vs 2.8 ± 3.5, P = 0.002) and a receiver operating characteristic area under the curve of 0.842. CONCLUSION: A novel validated score for the assessment of haemorrhoidal disease adopting a standardized global score for symptom severity may have important implications in future for research, assessment and the management of this common pathology.

A pilot randomised controlled trial evaluating postoperative packing of the perianal abscess.

PURPOSE: Traditional management of a perianal abscess involves incision and drainage followed by packing of the cavity until healing by secondary intention is complete. The evidence supporting this is lacking however, and regular postoperative packing is time-consuming, painful and costly. This pilot study aimed to assess whether healing could be achieved safely without packing and to obtain preliminary results to enable sample size calculation in order to facilitate the implementation of a large multicentre randomised controlled trial. ClinicalTrials.gov Identifier: NCT01853267. METHODS: Fourteen patients with perianal abscesses were randomised to packing or non-packing of the abscess cavity postoperatively. Outcome measures were time to healing, abscess recurrence, fistula formation and postoperative pain. RESULTS: Healing in the non-packing group was faster compared to the packing group: mean 26.8 days (95 % confidence interval 22.7 to 30.7) vs 19.5 days (13.6 to 25.4); P = 0.047. There were no differences in recurrence rates between the groups (37.5 % packing group vs 33.3 % non-packing group; P = 0.580) at a median follow-up of 90.0 weeks (interquartile range (IQR) 26.0). In patients presenting with recurrence, one fistula was found in the packing group with no fistulas in the non-packing group. The non-packing group reported less pain 2 weeks postoperatively: median (IQR) 2.00 (3.00) vs 0.00 (1.00); (P = 0.030). CONCLUSION: Within the limitations of a small sample population, the results of this pilot study suggest that not packing the perianal abscess cavity after incision and drainage is safe. Our results show not packing confers less pain with a faster healing time compared with the conventional packing method, and this is a novel finding. These results need to be corroborated in the setting of a larger multicentre randomised controlled trial.

Uptake of tamoxifen in consecutive premenopausal women under surveillance in a high-risk breast cancer clinic.

BACKGROUND: Randomised trials of tamoxifen versus placebo indicate that tamoxifen reduces breast cancer risk by approximately 33%, yet uptake is low. Approximately 10% of women in our clinic entered the IBIS-I prevention trial. We assess the uptake of tamoxifen in a consecutive series of premenopausal women not in a trial and explore the reasons for uptake through interviews. METHODS: All eligible women between 33 and 46 years at ≥17% lifetime risk of breast cancer and undergoing annual mammography in our service were invited to take a 5-year course of tamoxifen. Reasons for accepting (n=15) or declining (n=15) were explored using semi-structured interviews. RESULTS: Of 1279 eligible women, 136 (10.6%) decided to take tamoxifen. Women >40 years (74 out of 553 (13.4%)) and those at higher non-BRCA-associated risk were more likely to accept tamoxifen (129 out of 1109 (11.6%)). Interviews highlighted four themes surrounding decision making: perceived impact of side effects, the impact of others' experience on beliefs about tamoxifen, tamoxifen as a 'cancer drug', and daily reminder of cancer risk. CONCLUSIONS: Tamoxifen uptake was similar to previously ascertained uptake in a randomised controlled trial (IBIS-I). Concerns were similar in women who did or did not accept tamoxifen. Decision making appeared to be embedded in the experience of significant others.

Relationships between CYP2D6 phenotype, breast cancer and hot flushes in women at high risk of breast cancer receiving prophylactic tamoxifen: results from the IBIS-I trial.

BACKGROUND: Several studies have reported discordant results regarding the impact of the CYP2D6 phenotype on both the effectiveness and the degree of endocrine symptoms associated with tamoxifen. Other studies have suggested that menopausal symptoms may be a predictive factor to tamoxifen response. METHODS: We investigated the relationship between the CYP2D6-predicted phenotype and tamoxifen response in a nested case-control study among women from the International Breast cancer Intervention Study (IBIS-I), which evaluated tamoxifen in the preventive setting. RESULTS: In this retrospective analysis of the tamoxifen-treated women in the IBIS-I study, 9 women (16.6%) who developed oestrogen receptor-positive invasive breast cancer had a 2D6 poor or intermediate metaboliser phenotype compared with 45 (20.6%) controls. Adjusted matched logistic regression revealed no significant difference between cases and controls for extensive vs intermediate metaboliser phenotype (OR=0.81 (0.30-2.23), P=0.7) or extensive vs poor metaboliser phenotype (OR=1.02 (0.31-3.32), P=0.9). Controls in the tamoxifen group with a poor metaboliser phenotype developed nonsignificantly fewer hot flushes compared with those with an extensive metaboliser phenotype (OR=0.40 (0.12-1.31)), but those with the intermediate phenotype developed nonsignificantly more hot flushes (OR=1.38 (0.58-3.29)) in an unadjusted analysis. CONCLUSION: Data from the preventive IBIS-I study did not support an association between the CYP2D6 phenotype and breast cancer outcome or the development of endocrine symptoms in tamoxifen-treated women.

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.

Patient reported outcome measures in a cohort of patients at high risk of breast cancer treated by bilateral risk reducing mastectomy and breast reconstruction.

BACKGROUND: Many women with increased lifetime risk of developing breast cancer, due to pathogenic gene variants or family history, choose to undergo bilateral risk reducing mastectomies (BRRM). Patient reported outcome measures (PROMS) are an increasingly important part of informed consent but are little studied in women undergoing BRRM. METHODS: We used a validated PROMS tool for breast reconstruction (BREAST-Q) in 297 women who had BRRM and breast reconstruction, 81% of whom had no malignancy (Benign Group, BG) and 19% in whom a perioperative breast cancer was diagnosed (Cancer Group, CG). 128 women also completed a Hospital Anxiety & Depression Score (HADS) questionnaire to test if preoperative HADS score could predict PROMS outcomes. RESULTS: Women in the CG had lower PROMS scores for satisfaction with their breasts, nipple reconstruction and sexual wellbeing. Both groups reported equal satisfaction with BRRM outcome and psychosocial well-being. Physical well-being PROMS of the abdomen and chest were high in women in both groups as were scores for satisfaction with the care they received. The CG group reported suboptimal quality of patient information. A higher presurgical HADS anxiety score predicted less favourable postoperative psychosocial well-being despite similar levels of satisfaction with aesthetic outcome. CONCLUSION: We show a high degree of patient reported satisfaction by woman undergoing BRRM and reconstruction. There was a negative association with a cancer diagnosis on quality of life PROMS and higher preoperative anxiety levels negatively affected postoperative psychosocial well-being. These important findings should be part of the informed consent process during preoperative counselling.

Safety of the use of gold nanoparticles conjugated with proinsulin peptide and administered by hollow microneedles as an immunotherapy in type 1 diabetes.

Antigen-specific immunotherapy is an immunomodulatory strategy for autoimmune diseases, such as type 1 diabetes, in which patients are treated with autoantigens to promote immune tolerance, stop autoimmune ß-cell destruction and prevent permanent dependence on exogenous insulin. In this study, human proinsulin peptide C19-A3 (known for its positive safety profile) was conjugated to ultrasmall gold nanoparticles (GNPs), an attractive drug delivery platform due to the potential anti-inflammatory properties of gold. We hypothesised that microneedle intradermal delivery of C19-A3 GNP may improve peptide pharmacokinetics and induce tolerogenic immunomodulation and proceeded to evaluate its safety and feasibility in a first-in-human trial. Allowing for the limitation of the small number of participants, intradermal administration of C19-A3 GNP appears safe and well tolerated in participants with type 1 diabetes. The associated prolonged skin retention of C19-A3 GNP after intradermal administration offers a number of possibilities to enhance its tolerogenic potential, which should be explored in future studies.

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.

Long-term effects of anastrozole on bone mineral density: 7-year results from the ATAC trial.

BACKGROUND: This 'Arimidex', Tamoxifen, Alone or in Combination (ATAC) trial sub-study examined the effects of anastrozole and tamoxifen on bone mineral density (BMD) following 5 years of treatment. PATIENTS AND METHODS: Lumbar spine and total hip BMD were assessed at years 6 and 7 in a total of 71 eligible patients. In total, 50 patients had evaluable data. RESULTS: Following anastrozole treatment, the lumbar spine median BMD increased by 2.35% (P=0.04) and 4.02% (P=0.0004) at years 6 and 7, while total hip median BMD increased by 0.71% (P=0.3) and 0.5% (P=0.8). After tamoxifen treatment, lumbar spine median BMD decreased by 0.79% (P=0.2) and 0.30% (P=0.9) at years 6 and 7, while total hip median BMD decreased by 2.09% (P=0.0003) and 2.52% (P=0.0002). Patients with a normal BMD or who were osteopenic at 5 years did not become osteoporotic. CONCLUSIONS: Anastrozole treatment-related bone loss did not continue into the off-treatment follow-up period. The recovery in lumbar spine BMD and absence of further loss at the hip is consistent with the reduction in the annual rate of fracture observed after treatment cessation in the main ATAC trial.