Collaborative Modeling to Compare Different Breast Cancer Screening Strategies: A Decision Analysis for the US Preventive Services Task Force.

Importance: The effects of breast cancer incidence changes and advances in screening and treatment on outcomes of different screening strategies are not well known. Objective: To estimate outcomes of various mammography screening strategies. Design, Setting, and Population: Comparison of outcomes using 6 Cancer Intervention and Surveillance Modeling Network (CISNET) models and national data on breast cancer incidence, mammography performance, treatment effects, and other-cause mortality in US women without previous cancer diagnoses. Exposures: Thirty-six screening strategies with varying start ages (40, 45, 50 years) and stop ages (74, 79 years) with digital mammography or digital breast tomosynthesis (DBT) annually, biennially, or a combination of intervals. Strategies were evaluated for all women and for Black women, assuming 100% screening adherence and "real-world" treatment. Main Outcomes and Measures: Estimated lifetime benefits (breast cancer deaths averted, percent reduction in breast cancer mortality, life-years gained), harms (false-positive recalls, benign biopsies, overdiagnosis), and number of mammograms per 1000 women. Results: Biennial screening with DBT starting at age 40, 45, or 50 years until age 74 years averted a median of 8.2, 7.5, or 6.7 breast cancer deaths per 1000 women screened, respectively, vs no screening. Biennial DBT screening at age 40 to 74 years (vs no screening) was associated with a 30.0% breast cancer mortality reduction, 1376 false-positive recalls, and 14 overdiagnosed cases per 1000 women screened. Digital mammography screening benefits were similar to those for DBT but had more false-positive recalls. Annual screening increased benefits but resulted in more false-positive recalls and overdiagnosed cases. Benefit-to-harm ratios of continuing screening until age 79 years were similar or superior to stopping at age 74. In all strategies, women with higher-than-average breast cancer risk, higher breast density, and lower comorbidity level experienced greater screening benefits than other groups. Annual screening of Black women from age 40 to 49 years with biennial screening thereafter reduced breast cancer mortality disparities while maintaining similar benefit-to-harm trade-offs as for all women. Conclusions: This modeling analysis suggests that biennial mammography screening starting at age 40 years reduces breast cancer mortality and increases life-years gained per mammogram. More intensive screening for women with greater risk of breast cancer diagnosis or death can maintain similar benefit-to-harm trade-offs and reduce mortality disparities.

Alternative dosing regimen of exemestane in a randomized presurgical trial: the role of obesity in biomarker modulation.

In a 3-arm presurgical trial, four-six weeks exemestane 25 mg three times/week (TIW) was non-inferior to 25 mg/day (QD) in suppressing circulating estradiol in postmenopausal women with ER-positive breast cancer. Since obesity may decrease exemestane efficacy, we analyzed changes in sex steroids, adipokines, Ki-67, and drug levels in relation to obesity. Postmenopausal women with early-stage ER-positive breast cancer were randomized to either exemestane 25 mg QD (n = 57), 25 mg TIW (n = 57), or 25 mg/week (QW, n = 62) for 4-6 weeks before breast surgery. Serum and tissue pre- and post-treatment biomarkers were stratified by body mass index (BMI)< or ≥30 kg/m2. Post-treatment median exemestane and 17-OH exemestane levels were 5-6 times higher in the QD arm compared to the TIW arm. For obese women, TIW maintained comparable reductions to QD in systemic estradiol levels, although the reduction in estrone was less with the TIW regimen. There was less suppression of SHBG with the TIW versus the QD dose schedule in obese women which should result in less systemic bioavailable estrogens. Metabolically, the effect of the TIW regimen was similar to the QD regimen for obese women in terms of leptin suppression and increase in the adiponectin-leptin ratio. Reduction in tissue Ki-67 was less for obese women on the TIW regimen than QD, although changes were similar for non-obese women. Our findings suggest that TIW exemestane should be explored further for primary cancer prevention in both normal weight and obese cohorts.

A randomized Phase I pre-operative window trial of transdermal endoxifen in women planning mastectomy: Evaluation of dermal safety, intra-mammary drug distribution, and biologic effects.

Breast cancer prevention only requires local exposure of the breast to active drug. However, oral preventive agents entail systemic exposure, causing adverse effects that limit acceptance by high-risk women. Drug-delivery through the breast skin is an attractive option, but requires demonstration of dermal safety and drug distribution throughout the breast. We formulated the tamoxifen metabolite (E/Z)-endoxifen for transdermal delivery and tested it in a placebo-controlled, double-blinded Phase I trial with dose escalation from 10 to 20 mg daily. The primary endpoint was dermal toxicity. Thirty-two women planning mastectomy were randomized (2:1) to endoxifen-gel or placebo-gel applied to both breasts for 3-5 weeks. Both doses of endoxifen-gel incurred no dermal or systemic toxicity compared to placebo. All endoxifen-treated breasts contained the drug at each of five sampling locations; the median per-person tissue concentration in the treated participants was 0.6 ng/g (IQR 0.4-1.6), significantly higher (p < 0.001) than the median plasma concentration (0.2 ng/mL, IQR 0.2-0.2). The median ratio of the more potent (Z)-isomer to (E)-isomer at each breast location was 1.50 (IQR 0.96-2.54, p < 0.05). No discernible effects of breast size or adiposity on tissue concentrations were observed. At the endoxifen doses and duration used, and the tissue concentration achieved, we observed a non-significant overall reduction of tumor proliferation (Ki67 LI) and significant downregulation of gene signatures known to promote cancer invasion (FN1, SERPINH1, PLOD2, PDGFA, ITGAV) (p = 0.03). Transdermal endoxifen is an important potential breast cancer prevention agent but formulations with better dermal penetration are needed.

Presurgical Oral Tamoxifen vs Transdermal 4-Hydroxytamoxifen in Women With Ductal Carcinoma In Situ: A Randomized Clinical Trial.

Importance: Oral tamoxifen citrate benefits women with ductal carcinoma in situ (DCIS), but concern about toxic effects has limited acceptance. Previous pilot studies have suggested transdermal 4-hydroxytamoxifen gel has equivalent antiproliferative efficacy to oral tamoxifen, with low systemic exposure. Objective: To demonstrate that 4-hydroxytamoxifen gel applied to the breast skin is noninferior to oral tamoxifen in its antiproliferative effect in DCIS lesions. Design, Setting, and Participants: This randomized, double-blind, phase 2 preoperative window trial was performed at multicenter breast surgery referral practices from May 31, 2017, to January 27, 2021. Among 408 women with estrogen receptor-positive DCIS who were approached, 120 consented and 100 initiated study treatment. The most common reasons for nonparticipation were surgical delay, disinterest in research, and concerns about toxic effects. Data were analyzed from January 26, 2021, to October 5, 2022. Intervention: Random assignment to oral tamoxifen citrate, 20 mg/d, and gel placebo or 4-hydroxytamoxifen gel, 2 mg/d per breast, and oral placebo, for 4 to 10 weeks, followed by DCIS resection. Main Outcomes and Measures: The primary end point was absolute change in DCIS Ki-67 labeling index (Ki67-LI). Secondary end points included 12-gene DCIS Score, breast tissue tamoxifen metabolite concentrations, tamoxifen-responsive plasma protein levels, and patient-reported symptoms. Noninferiority of Ki67-LI reduction by 4-hydroxytamoxifen gel was tested using analysis of covariance; within- and between-arm comparisons were performed with paired t tests for mean values or the Wilcoxon rank sum test for medians. Results: Of 90 participants completing treatment (mean [SD] age, 55 [11] years; 8 [8.9%] Asian, 16 [17.8%] Black, 8 [8.9%] Latina, and 53 [58.9%] White), 15 lacked residual DCIS in the surgical sample, leaving 75 evaluable for the primary end point analysis (40 in the oral tamoxifen group and 35 in the 4-hydroxytamoxifen gel group). Posttreatment Ki67-LI was 3.3% higher (80% CI, 2.1%-4.6%) in the 4-hydroxytamoxifen gel group compared with the oral tamoxifen group, exceeding the noninferiority margin (2.6%). The DCIS Score decreased more with oral tamoxifen treatment (-16 [95% CI, -22 to -9.4]) than with 4-hydroxytamoxifen gel (-1.8 [95% CI, -5.8 to 2.3]). The median 4-hydroxytamoxifen concentrations deep in the breast were nonsignificantly higher in the oral tamoxifen group (5.7 [IQR, 4.0-7.9] vs 3.8 [IQR, 1.3-7.9] ng/g), whereas endoxifen was abundant in the oral tamoxifen group and minimal in the 4-hydroxytamoxifen gel group (median, 13.0 [IQR, 8.9-20.6] vs 0.3 [IQR, 0-0.3] ng/g; P < .001). Oral tamoxifen caused expected adverse changes in plasma protein levels and vasomotor symptoms, with minimal changes in the transdermal group. Conclusions and Relevance: In this randomized clinical trial, antiproliferative noninferiority of 4-hydroxytamoxifen gel to oral tamoxifen was not confirmed, potentially owing to endoxifen exposure differences. New transdermal approaches must deliver higher drug quantities and/or include the most potent metabolites. Trial Registration: ClinicalTrials.gov Identifier: NCT02993159.

Phase II Trial of Nelipepimut-S Peptide Vaccine in Women with Ductal Carcinoma In Situ.

NeuVax is a vaccine comprised of the HER2-derived MHC class I peptide E75 (nelipepimut-S, NPS) combined with GM-CSF. We completed a randomized trial of preoperative vaccination with NeuVax versus GM-CSF alone in patients with ductal carcinoma in situ (DCIS). The primary objective was to evaluate for NPS-specific cytotoxic T lymphocyte (CTL) responses. Patients with human leukocyte antigen (HLA)-A2-positive DCIS were enrolled and randomized 2:1 to NeuVax versus GM-CSF alone and received two inoculations prior to surgery. The number of NPS-specific CTL was measured pre-vaccination, at surgery, and 1 and 3 to 6 months post-operation by dextramer assay. Differences in CTL responses between groups and between pre-vaccination and 1-month post-operation were analyzed using a two-sample t test or Wilcoxon rank sum test. The incidence and severity of adverse events were compared between groups. Overall, 45 patients were registered; 20 patients were HLA-A2 negative, 7 declined participation, 1 withdrew, and 4 failed screening for other reasons. The remaining 13 were randomized to NeuVax (n = 9) or GM-CSF alone (n = 4). Vaccination was well-tolerated with similar treatment-related toxicity between groups with the majority (>89%) of adverse events being grade 1. The percentage of NPS-specific CTLs increased in both arms between baseline (pre-vaccination) and 1-month post-operation. The increase was numerically greater in the NPS+GM-CSF arm, but the difference was not statistically significant. NPS+GM-CSF is safe and well-tolerated when given preoperatively to patients with DCIS. In patients with HLA-A2-positive DCIS, two inoculations with NPS+GM-CSF can induce in vivo immunity and a continued antigen-specific T-cell response 1-month postsurgery. PREVENTION RELEVANCE: This trial showed that vaccination of patients with HLA-A2-positive DCIS with NeuVax in the preoperative setting can induce a sustained antigen-specific T-cell response. This provides proof of principle that vaccination in the preoperative or adjuvant setting may stimulate an adaptive immune response that could potentially prevent disease recurrence.

Efficacy of Alternative Dose Regimens of Exemestane in Postmenopausal Women With Stage 0 to II Estrogen Receptor-Positive Breast Cancer: A Randomized Clinical Trial.

Importance: Successful therapeutic cancer prevention requires definition of the minimal effective dose. Aromatase inhibitors decrease breast cancer incidence in high-risk women, but use in prevention and compliance in adjuvant settings are hampered by adverse events. Objective: To compare the noninferiority percentage change of estradiol in postmenopausal women with estrogen receptor-positive breast cancer given exemestane, 25 mg, 3 times weekly or once weekly vs a standard daily dose with a noninferiority margin of -6%. Design, Setting, and Participants: This multicenter, presurgical, double-blind phase 2b randomized clinical trial evaluated 2 alternative dosing schedules of exemestane. Postmenopausal women with estrogen receptor-positive breast cancer who were candidates for breast surgery were screened from February 1, 2017, to August 31, 2019. Blood samples were collected at baseline and final visit; tissue biomarker changes were assessed from diagnostic biopsy and surgical specimen. Biomarkers were measured in different laboratories between April 2020 and December 2021. Interventions: Exemestane, 25 mg, once daily, 3 times weekly, or once weekly for 4 to 6 weeks before surgery. Main Outcomes and Measures: Serum estradiol concentrations were measured by solid-phase extraction followed by liquid chromatography-tandem mass spectrometry detection. Toxic effects were evaluated using the National Cancer Institute terminology criteria, and Ki-67 was assessed by immunohistochemistry. Results: A total of 180 women were randomized into 1 of the 3 arms; median (IQR) age was 66 (60-71) years, 63 (60-69) years, and 65 (61-70) years in the once-daily, 3-times-weekly, and once-weekly arms, respectively. In the intention-to-treat population (n = 171), the least square mean percentage change of serum estradiol was -89%, -85%, and -60% for exemestane once daily (n = 55), 3 times weekly (n = 56), and once weekly (n = 60), respectively. The difference in estradiol percentage change between the once-daily and 3-times-weekly arms was -3.6% (P for noninferiority = .37), whereas in compliant participants (n = 153), it was 2.0% (97.5% lower confidence limit, -5.6%; P for noninferiority = .02). Among secondary end points, Ki-67 and progesterone receptor were reduced in all arms, with median absolute percentage changes of -7.5%, -5.0%, and -4.0% for Ki-67 in the once-daily, 3-times-weekly, and once-weekly arms, respectively (once daily vs 3 times weekly, P = .31; once daily vs once weekly, P = .06), and -17.0%, -9.0%, and -7.0% for progesterone receptor, respectively. Sex hormone-binding globulin and high-density lipoprotein cholesterol had a better profile among participants in the 3-times-weekly arm compared with once-daily arm. Adverse events were similar in all arms. Conclusions and Relevance: In this randomized clinical trial, exemestane, 25 mg, given 3 times weekly in compliant patients was noninferior to the once-daily dosage in decreasing serum estradiol. This new schedule should be further studied in prevention studies and in women who do not tolerate the daily dose in the adjuvant setting. Trial Registration: ClinicalTrials.gov Identifier: NCT02598557; EudraCT: 2015-005063-16.

Phase I Dose Escalation Study of Topical Bexarotene in Women at High Risk for Breast Cancer.

PREVENTION RELEVANCE: Bexarotene is a rexinoid that has been shown to prevent mammary tumors in mouse models but oral dosing has toxicities. This phase I study evaluates topical bexarotene, as a potential chemoprevention agent, for safety and toxicity in high-risk women for breast cancer.

Breast cancer risk for women with diabetes and the impact of metformin: A meta-analysis.

BACKGROUND: Diabetes mellitus has been associated with increased breast cancer (BC) risk; however, the magnitude of this effect is uncertain. This study focused on BC risk for women with type 2 diabetes mellitus (T2DM). METHODS: Two separate meta-analyses were conducted (1) to estimate the relative risk (RR) of BC for women with T2DM and (2) to evaluate the risk of BC for women with T2DM associated with the use of metformin, a common diabetes treatment. In addition, subgroup analyses adjusting for obesity as measured by body mass index (BMI) and menopausal status were also performed. Studies were identified via PubMed/Scopus database and manual search through April 2021. RESULTS: A total of 30 and 15 studies were included in the first and second meta-analyses, respectively. The summary RR of BC for women with T2DM was 1.15 (95% confidence interval [CI], 1.09-1.21). The subgroup analyses adjusting BMI and adjusting BMI and menopause resulted in a summary RR of 1.22 (95% CI, 1.15-1.30) and 1.20 (95% CI, 1.05-1.36), respectively. For women with T2DM, the summary RR of BC was 0.82 (95% CI, 0.60-1.12) for metformin users compared with nonmetformin users. CONCLUSIONS: Women with T2DM were more likely to be diagnosed with BC and this association was strengthened by adjusting for BMI and menopausal status. No statistically significant reduction of BC risk was observed among metformin users. IMPACT: These two meta-analyses can inform decision-making for women with type 2 diabetes regarding their use of metformin and the use of screening mammography for early detection of breast cancer.

The 2018 World Cancer Research Fund (WCRF)/American Institute for Cancer Research (AICR) score and diabetes risk in the Diabetes Prevention Program Outcomes Study (DPPOS).

BACKGROUND: The 2018 World Cancer Research Fund/American Institute for Cancer Research (WCRF/AICR) 3rd expert report highlights up-to-date Cancer Prevention Recommendations that may reduce burdens of many chronic diseases, including diabetes. This study examined if following a lifestyle that aligns with the recommendations - assessed via the 2018 WCRF/AICR Score - was associated with lower risk of type 2 diabetes in high-risk adults participating in the Diabetes Prevention Program Outcomes Study (DPPOS). METHODS: The Diabetes Prevention Program (DPP) randomized adults at high risk for diabetes to receive a lifestyle intervention (ILS), metformin (MET) or a placebo (PLB) (mean: 3.2 years), with additional follow-up in DPPOS for 11 years (mean: 15 years total). 2018 WCRF/AICR Scores included seven components: body weight, physical activity, plant-based foods, fast foods, red and processed meat, sugar-sweetened beverages, and alcohol; the optional breastfeeding component was excluded. Scores ranged 0-7 points (with greater scores indicating greater alignment with the recommendations) and were estimated at years 0, 1, 5, 6, 9, and 15 (N=3,147). Fasting glucose and HbA1c were measured every six months and oral glucose tolerance tests were performed annually. Adjusted Cox proportional hazard ratios (HRs) and 95% confidence intervals (CIs) were used to examine the association of both Score changes from years 0-1 and time-dependent Score changes on diabetes risk through DPP and year 15. RESULTS: Scores improved within all groups over 15 years (p<0.001); ILS Scores improved more than MET or PLB Scores after 1 year (p<0.001). For every 1-unit improvement from years 0-1, there was a 31% and 15% lower diabetes risk in ILS (95% CI: 0.56-0.84) and PLB (95% CI: 0.72-0.97) through DPP, and no significant association in MET. Associations were greatest among American Indian participants, followed by non-Hispanic White and Hispanic participants. Score changes from years 0-1 and time-dependent Score changes in ILS and PLB remained associated with lower risk through year 15. CONCLUSIONS: Score improvements were associated with long-term, lower diabetes risk among high-risk adults randomized to ILS and PLB, but not MET. Future research should explore impact of the Score on cancer risk. TRIAL REGISTRATION: Diabetes Prevention Program: NCT00004992 ; Diabetes Prevention Program Outcomes Study: NCT00038727.

Lessons from the Failure to Complete a Trial of Denosumab in Women With a Pathogenic BRCA1/2 Variant Scheduling Risk-Reducing Salpingo-Oophorectomy.

Female carriers of pathogenic/likely pathogenic (P/LP) BRCA1/2 variants are at increased risk of developing breast and ovarian cancer. Currently, the only effective strategy for ovarian cancer risk reduction is risk-reducing bilateral salpingo-oophorectomy (RR-BSO), which carries adverse effects related to early menopause. There is ongoing investigation of inhibition of the RANK ligand (RANKL) with denosumab as a means of chemoprevention for breast cancer in carriers of BRCA1 P/LP variants. Through the NCI Division of Cancer Prevention (DCP) Early Phase Clinical Trials Prevention Consortia, a presurgical pilot study of denosumab was developed in premenopausal carriers of P/LP BRCA1/2 variants scheduled for RR-BSO with the goal of collecting valuable data on the biologic effects of denosumab on gynecologic tissue. The study was terminated early due to the inability to accrue participants. Challenges which impacted the conduct of this study included a study design with highly selective eligibility criteria and requirements and the COVID-19 pandemic. It is critical to reflect on these issues to enhance the successful completion of future prevention studies in individuals with hereditary cancer syndromes.

Time-Restricted Feeding Studies and Possible Human Benefit.

Metabolic syndrome consists of a constellation of clinical factors associated with an increased risk of cardiovascular disease, type 2 diabetes, and cancer. Preclinical studies demonstrate that restricting the time during a 24-hour period when an obese animal eats (time-restricted feeding) leads to metabolic benefits. These benefits, which may or may not be associated with weight loss, often lead to improvements in glucose tolerance and insulin sensitivity. Studies seeking to determine whether similar benefits result when humans restrict daily eating time (time-restricted eating) are less mature and less consistent in their findings. In this commentary, we outline some of the exciting preclinical findings, the challenges that preliminary studies in humans present, and efforts of the US National Institutes of Health and specifically the National Cancer Institute to address the role of time-restricted eating in cancer.

Report from an NCI Roundtable: Cancer Prevention in Primary Care.

The Division of Cancer Prevention in the NCI sponsored a Roundtable with primary care providers (PCP) to determine barriers for integrating cancer prevention within primary care and discuss potential opportunities to overcome these barriers. The goals were to: (i) assess the cancer risk assessment tools available to PCPs; (ii) gather information on use of cancer prevention resources; and (iii) understand the needs of PCPs to facilitate the implementation of cancer prevention interventions beyond routine screening and interventions. The Roundtable discussion focused on challenges and potential research opportunities related to: (i) cancer risk assessment and management of high-risk individuals; (ii) cancer prevention interventions for risk reduction; (iii) electronic health records/electronic medical records; and (iv) patient engagement and information dissemination. Time constraints and inconsistent/evolving clinical guidelines are major barriers to effective implementation of cancer prevention within primary care. Social determinants of health are important factors that influence patients' adoption of recommended preventive interventions. Research is needed to determine the best means for implementation of cancer prevention across various communities and clinical settings. Additional studies are needed to develop tools that can help providers collect clinical data that can enable them to assess patients' cancer risk and implement appropriate preventive interventions.

Meta-analysis of agreement/concordance statistics in studies comparing self- vs clinician-collected samples for HPV testing in cervical cancer screening.

We conducted a meta-analysis of test agreement/concordance between human papillomavirus (HPV) testing in self-collected vs clinician-collected samples in 26 studies (10 071 participants) updating a previous meta-analysis on accuracy for cervical precancer. Pooled overall agreement was 88.7% (95% CI: 86.3%-90.9%), positive agreement was 84.6% (95% CI: 79.9%-88.7%), negative agreement was 91.7% (95% CI: 89.1%-94.0%) and kappa was 0.72 (95% CI: 0.66-0.78). Subgroup meta-analyses suggested higher overall agreement for target amplification-based DNA assays (90.4%) compared to signal amplification-based DNA assays (86.7%; P = .175) or RNA assays (82.3%; P < .001). HPV test agreement/concordance targets may provide criteria to extend existing validations toward alternative sampling approaches and devices/storage media.

Redefining precision cancer prevention to promote health equity.

Precision cancer prevention as it is currently envisioned is a targeted, molecular-based approach to intercept carcinogenesis before cancer develops or before it becomes untreatable. Unfortunately, due to systemic biases, current precision cancer prevention interventions might not be effective in all populations, especially in minoritized communities. In addition, not all cancer risk is attributable to genetic or even biological factors, but includes social determinants of health (SDH). Here, we propose a broader framework for precision cancer prevention, anchored in optimizing the benefits to harms for all people. We propose that precision cancer prevention considers not only what is being delivered, but also for whom, where, and how, with a goal of achieving cancer prevention health equity.

Effect of Metformin and Lifestyle Interventions on Mortality in the Diabetes Prevention Program and Diabetes Prevention Program Outcomes Study.

OBJECTIVE: To determine whether metformin or lifestyle modification can lower rates of all-cause and cause-specific mortality in the Diabetes Prevention Program and Diabetes Prevention Program Outcomes Study. RESEARCH DESIGN AND METHODS: From 1996 to 1999, 3,234 adults at high risk for type 2 diabetes were randomized to an intensive lifestyle intervention, masked metformin, or placebo. Placebo and lifestyle interventions stopped in 2001, and a modified lifestyle program was offered to everyone, but unmasked study metformin continued in those originally randomized. Causes of deaths through 31 December 2018 were adjudicated by blinded reviews. All-cause and cause-specific mortality hazard ratios (HRs) were estimated from Cox proportional hazards regression models and Fine-Gray models, respectively. RESULTS: Over a median of 21 years (interquartile range 20-21), 453 participants died. Cancer was the leading cause of death (n = 170), followed by cardiovascular disease (n = 131). Compared with placebo, metformin did not influence mortality from all causes (HR 0.99 [95% CI 0.79, 1.25]), cancer (HR 1.04 [95% CI 0.72, 1.52]), or cardiovascular disease (HR 1.08 [95% CI 0.70, 1.66]). Similarly, lifestyle modification did not impact all-cause (HR 1.02 [95% CI 0.81, 1.28]), cancer (HR 1.07 [95% CI 0.74, 1.55]), or cardiovascular disease (HR 1.18 [95% CI 0.77, 1.81]) mortality. Analyses adjusted for diabetes status and duration, BMI, cumulative glycemic exposure, and cardiovascular risks yielded results similar to those for all-cause mortality. CONCLUSIONS: Cancer was the leading cause of mortality among adults at high risk for type 2 diabetes. Although metformin and lifestyle modification prevented diabetes, neither strategy reduced all-cause, cancer, or cardiovascular mortality rates.

Metabolic Surgery and Cancer Risk: An Opportunity for Mechanistic Research.

Metabolic (bariatric) surgery (MBS) is recommended for individuals with a BMI > 40 kg/m2 or those with a BMI 35-40 kg/m2 who have one or more obesity related comorbidities. MBS leads to greater initial and sustained weight loss than nonsurgical weight loss approaches. MBS provides dramatic improvement in metabolic function, associated with a reduction in type 2 diabetes mellitus and cardiovascular risk. While the number of MBS procedures performed in the U.S. and worldwide continues to increase, they are still only performed on one percent of the affected population. MBS also appears to reduce the risk of certain obesity related cancers, although which cancers are favorably impacted vary by study, who benefits most is uncertain, and the mechanism(s) driving this risk reduction are mostly speculative. The goal of this manuscript is to highlight (1) emerging evidence that MBS influences cancer risk, and that the potential benefit appears to vary based on cancer, gender, surgical procedure, and likely other variables; (2) the role of the NIH in MBS research in T2DM and CV risk for many years, and more recently in cancer; and (3) the opportunity for research to understand the mechanism(s) by which MBS influences cancer. There is evidence that women benefit more from MBS than men, that MBS may actually increase the risk of colorectal cancer in both women and men, and there is speculation that the benefit in cancer risk reduction may vary according to which MBS procedure an individual undergoes. Herein, we review what is currently known, the historical role of government, especially the National Institutes of Health (NIH), in driving this research, and provide suggestions that we believe could lead to a better understanding of whether and how MBS impacts cancer risk, which cancers are impacted either favorably or unfavorably, the role of the NIH and other research agencies, and key questions to address that will help us to move the science forward.

Alternative dosing of exemestane in postmenopausal women with ER-positive breast cancer. Design and methods of a randomized presurgical trial.

INTRODUCTION: Aromatase inhibitors are effective in lowering breast cancer incidence among postmenopausal women, but adverse events represent a barrier to their acceptability and adherence as a preventive treatment. This study aims to assess whether lowering exemestane schedule may retain biological activity while improving tolerability in breast cancer patients. METHODS/DESIGN: We are conducting a, pre-surgical, non-inferiority phase IIb study in postmenopausal women with newly diagnosed estrogen receptor-positive breast cancer. Participants are randomized to receive either exemestane 25 mg/day or 25 mg/three times-week or once a week for 4 to 6 weeks prior to surgery. The primary endpoint is the percentage change of serum estradiol concentration between baseline and surgery comparing the three arms. Sample size of 180 women was calculated assuming a 6% non-inferiority of the percent change of estradiol in the lower dose arms compared with the 80% decrease predicted in the full dose arm, with 80% power and using a one-sided 5% significance level and a two-sample t-test. Main secondary outcomes are: safety; change in Ki-67 in cancer and adjacent pre-cancer tissue, circulating sex hormones, adipokines, lipid profile, insulin and glucose changes, in correlation with drug and metabolites concentrations. RESULTS AND DISCUSSION: The present paper is focused on methodology and operational aspects of the study. A total of 180 participants have ben enrolled. The trial is still blinded, and the analyses are ongoing. Despite the short term duration, results may have relevant implications for clinical management of women at increased risk of developing a ER positive breast cancer.

Local Transdermal Delivery of Telapristone Acetate Through Breast Skin, Compared With Oral Treatment: A Randomized Double-Blind, Placebo-Controlled Phase II Trial.

Oral breast cancer prevention medications entail systemic exposure, limiting acceptance by high-risk women. Delivery through the breast skin, although an attractive alternative, requires demonstration of drug distribution throughout the breast. We conducted a randomized double-blind, placebo-controlled phase II clinical trial comparing telapristone acetate, a progesterone receptor antagonist, administered orally (12 mg/day) or transdermally (12 mg/breast) for 4 ± 1 weeks to women planning mastectomy. Plasma and tissue concentrations, measured at five locations in the mastectomy specimen using liquid chromatography tandem mass spectrometry were compared. In 60 evaluable subjects, median drug concentration (ng/g tissue) was 103 (interquartile range (IQR): 46.3-336) in the oral vs. 2.82 (IQR: 1.4-5.5) in the transdermal group. Despite poor dermal permeation, within-breast drug distribution pattern was identical in both groups (R2  = 0.88, P = 0.006), demonstrating that transdermally and orally delivered drug is distributed similarly through the breast, and is strongly influenced by tissue adiposity (P < 0.0001). Other skin-penetrant drugs should be tested for breast cancer prevention.