Association of dry matter intake and energy balance prepartum and postpartum with health disorders postpartum: Part II. Ketosis and clinical mastitis

The main objective of this study was to determine the association of dry matter intake as percentage of body weight (DMI%BW) and energy balance (EB) prepartum (-21 d relative to parturition) and postpartum (28 d) with ketosis (n = 189) and clinical mastitis (n = 79). For this, DMI%BW and EB were the independent variables and ketosis and clinical mastitis were the dependent variables. A secondary objective was to evaluate prepartum DMI%BW and EB as predictors of ketosis and clinical mastitis. For this, ketosis and clinical mastitis were the independent variables and DMI%BW and EB were the dependent variables. Data from 476 cows from 9 experiments were compiled. Clinical mastitis was diagnosed if milk from 1 or more quarters was abnormal in color, viscosity, or consistency, with or without accompanying heat, pain, redness, or swelling of the quarter or generalized illness, during the first 28 d postpartum. Ketosis was defined as the presence of acetoacetate in urine that resulted in any color change [5 mg/dL (trace) or higher] in the urine test strip (Ketostix, Bayer, Leverkusen, Germany). Cows that developed ketosis had lesser DMI%BW and lesser EB on d -5, -3, -2, and -1 than cows without ketosis. Each 0.1-percentage point decrease in the average DMI%BW and each 1-Mcal decrease in the average of EB in the last 3 d prepartum increased the odds of having ketosis by 8 and 5%, respectively. Cut-offs for DMI%BW and EB during the last 3 d prepartum to predict ketosis were established and were ≤1.5%/d and ≤1.1 Mcal/d, respectively. Cows that developed ketosis had lesser postpartum DMI%BW and EB and greater energy-corrected milk (ECM) than cows without ketosis. Cows that developed clinical mastitis had lesser DMI%BW but similar prepartum EB compared with cows without clinical mastitis. Each 0.1-percentage point decrease in the average DMI%BW and each 1-Mcal decrease in the average EB in the last 3 d prepartum increased the odds of having clinical mastitis by 10 and 8%, respectively. The average DMI%BW and EB during the last 3 d prepartum produced significant cut-offs to predict clinical mastitis postpartum, which were ≤1.2%/d and ≤1.0 Mcal/d, respectively. Cows that developed clinical mastitis had lesser postpartum DMI%BW from d 3 to 15 and on d 17; greater EB on d 18, from d 21 to 23, and on d 26; and lesser ECM. The main limitation in this study is that the time-order of disease relative to DMI%BW and ECM is inconsistent such that postpartum outcomes were measured before and after disease, which was diagnosed at variable intervals after calving. In summary, measures of prepartum DMI were associated with and were predictors of ketosis and clinical mastitis postpartum, although the effect sizes were small.

Association of dry matter intake and energy balance prepartum and postpartum with health disorders postpartum: Part I. Calving disorders and metritis

The main objective of this study was to determine the association of dry matter intake as percentage of body weight (DMI%BW) and energy balance (EB) prepartum (-21 d relative to parturition) and postpartum (28 d) with calving disorders (CDZ; dystocia, twins, and stillbirths; n = 101) and metritis (n = 114). For this, DMI%BW and EB were the independent variables and CDZ and metritis were the dependent variables. A secondary objective was to evaluate prepartum DMI%BW and EB as predictors of CDZ and metritis. For this, CDZ and metritis were the independent variables and DMI%BW and EB were the dependent variables. Data from 476 cows from 9 experiments were compiled. Cows that developed CDZ had lesser postpartum DMI%BW from d 3 to 12 and lesser energy-corrected milk (ECM) than cows that did not develop CDZ. Dry matter intake as percentage of BW and EB prepartum did not affect the odds of CDZ. Cows with metritis had lesser prepartum DMI%BW and EB. Each 0.1-percentage point decrease in the average DMI%BW and each 1-Mcal decrease in the average EB in the last 3 d prepartum increased the odds of having metritis by 8%. The average DMI%BW and EB during the last 3 d prepartum produced significant cut-offs to predict metritis postpartum, which were ≤1.6%/d and ≤2.5 Mcal/d, respectively. Cows that developed metritis had lesser overall postpartum DMI%BW and ECM and lesser EB from d 2 to 5 and from d 7 to 11 than cows that did not develop metritis. The main limitation in this study is that the time-order of disease relative to DMI%BW and ECM is inconsistent such that postpartum outcomes were measured before and after disease, which was diagnosed at variable intervals after calving. In summary, prepartum DMI%BW and EB were associated with and were predictors of metritis although the effect sizes were small for metritis, and calving disorders and metritis were associated with decreased DMI%BW and ECM postpartum.

mTORC2/Akt activation in adipocytes is required for adipose tissue inflammation in tuberculosis

Background

Mycobacterium tuberculosis has co-evolved with the human host, adapting to exploit the immune system for persistence and transmission. While immunity to tuberculosis (TB) has been intensively studied in the lung and lymphoid system, little is known about the participation of adipose tissues and non-immune cells in the host-pathogen interaction during this systemic disease.

Methods

C57BL/6J mice were aerosol infected with M. tuberculosis Erdman and presence of the bacteria and the fitness of the white and brown adipose tissues, liver and skeletal muscle were studied compared to uninfected mice.

Findings

M. tuberculosis infection in mice stimulated immune cell infiltration in visceral, and brown adipose tissue. Despite the absence of detectable bacterial dissemination to fat tissues, adipocytes produced localized pro-inflammatory signals that disrupted adipocyte lipid metabolism, resulting in adipocyte hypertrophy. Paradoxically, this resulted in increased insulin sensitivity and systemic glucose tolerance. Adipose tissue inflammation and enhanced glucose tolerance also developed in obese mice after aerosol M. tuberculosis infection. We found that infection induced adipose tissue Akt signaling, while inhibition of the Akt activator mTORC2 in adipocytes reversed TB-associated adipose tissue inflammation and cell hypertrophy.

Interpretation

Our study reveals a systemic response to aerosol M. tuberculosis infection that regulates adipose tissue lipid homeostasis through mTORC2/Akt signaling in adipocytes. Adipose tissue inflammation in TB is not simply a passive infiltration with leukocytes but requires the mechanistic participation of adipocyte signals.

Effects of neratinib on health-related quality of life in women with HER2-positive early-stage breast cancer: longitudinal analyses from the randomized phase III ExteNET trial

BACKGROUND

We report longitudinal health-related quality-of-life (HRQoL) data from the international, randomized, double-blind, placebo-controlled phase III ExteNET study, which demonstrated an invasive disease-free survival benefit of extended adjuvant therapy with neratinib over placebo in human epidermal growth factor receptor-2-positive early-stage breast cancer.

PATIENTS AND METHODS

Women (N  = 2840) with early-stage HER2-positive breast cancer who had completed trastuzumab-based adjuvant therapy were randomly assigned to neratinib 240  mg/day or placebo for 12  months. HRQoL was an exploratory end point. Patients completed the Functional Assessment of Cancer Therapy-Breast (FACT-B) and EuroQol 5-Dimensions (EQ-5D) questionnaires at baseline and months 1, 3, 6, 9, and 12. Changes from baseline were compared using analysis of covariance with no imputation for missing values. Sensitivity analyses used alternative methods. Changes in HRQoL scores were regarded as clinically meaningful if they exceeded previously reported important differences (IDs).

RESULTS

Of the 2840 patients (intention-to-treat population), 2407 patients were evaluable for FACT-B (neratinib, N  = 1171; placebo, N  = 1236) and 2427 patients for EQ-5D (neratinib, N  = 1186; placebo, N  = 1241). Questionnaire completion rates exceeded 85%. Neratinib was associated with a decrease in global HRQoL scores at month 1 compared with placebo (adjusted mean differences: FACT-B total, -2.9 points; EQ-5D index, -0.02), after which between-group differences diminished at later time-points. Except for the FACT-B physical well-being (PWB) subscale at month 1; all between-group differences were less than reported IDs. The FACT-B breast cancer-specific subscale showed small improvements with neratinib at months 3-9, but all were less than IDs. Sensitivity analyses exploring missing data did not change the results.

CONCLUSIONS

Extended adjuvant neratinib was associated with a transient, reversible decrease in HRQoL during the first month of treatment, possibly linked to treatment-related diarrhea. With the exception of the PWB subscale at month 1, all neratinib-related HRQoL changes did not reach clinically meaningful thresholds. ClinicalTrials.gov: NCT00878709.

Abstract P6-17-07: Gene signatures and subtype changes during HER2 dual blockade in PAM50 HER2-enriched HER2-positive breast cancer

Background: HER2-positive (HER2+) breast cancer (BC) is composed of 4 molecular subtypes: Luminal A and B, HER2-enriched (HER2-E) and Basal-like. Among them, the HER2-E is highly sensitive to anti-HER2 treatment. However, ˜60% of HER2-E tumors do not achieve a pathological complete response (pCR) following neoadjuvant dual HER2 blockade without chemotherapy. Here, we aimed to better understand the molecular changes of the HER2-E subtype during anti-HER2 treatment.

Methods: Gene expression was evaluated in 101 patients with HER2-E tumors from the PAMELA neoadjuvant phase II trial (Lancet Oncol 2017). Briefly, women with HER2+ BC were treated with lapatinib and trastuzumab (and hormonal therapy if hormone receptor [HR]-positive) for 18 weeks. The median time between the last dose of treatment and surgery was 35 days (range=213; interquartile range=16). Expression of the PAM50 genes and 6 PAM50 signatures (Luminal A, Luminal B, HER2-E, Basal-like, normal-like and the PAM50 proliferation score) were determined using the nCounter platform at baseline (n=101), after 2 weeks of treatment (n=96) and in residual tumors (non-pCR) at surgery (n=57). Same analyses were done in 2 HER2+/HER2-E cell line models (BT474 [HR+] and SKBR3 [HR-]) following in vitro treatment with trastuzumab in combination with lapatinib. Biological changes between 2 time-points were determined by paired t-tests with a false discovery rate (FDR) <5%.

Results: After 2 weeks of treatment, 85.7% and 94.6% of the 56 genes/signatures were found differentially expressed (FDR<5%) in HER2-E/HR+ (n=35) and HER2-E/HR- (n=61) tumors, respectively. The two gene lists were highly correlated (correlation coefficient=0.93). Overall, a significant relative increase in Luminal A and normal-like signature scores, and a relative decrease in proliferation, HER2-E and Luminal B signature scores, were observed between baseline and week 2. Interestingly, a PAM50 subtype switch to Luminal A was observed in 31.6% and 4.8% of HER2-E/HR+ and HER2-E/HR- tumors. In BT474 and SKBR3, all genes/signatures were also found differentially expressed (FDR<5%) following 72h of dual HER2 blockade. The in vitro findings recapitulated the in vivo findings in 80-86% of the genes/signatures. Similar to tumors, a switch to a Luminal A subtype following dual HER2 blockade was observed in BT474 but not in SKBR3. Finally, 92.9% of the 56 genes/signatures were found differentially expressed (FDR<5%) in residual tumors at surgery compared to week 2. Contrary to the findings in the first 2 weeks of treatment, a general rebound effect in gene expression was observed between week 2 and surgery. Similarly, a rebound effect was observed in 60% of the genes/signatures in BT474 after removing anti-HER2 therapy for 72h, leading to a subtype switch from Luminal A back to HER2-E.

Conclusions: Dual HER2 blockade in the HER2-E subtype induces large biological changes that lead to a more low-proliferative Luminal A phenotype both in tumors and in vitro models, especially in HER2-E/HR+ disease. These phenotypic changes are reversible upon stopping anti-HER2 treatment. This finding supports the use of maintenance anti-HER2 treatment +/- endocrine therapy (if HR+) in advanced HER2+ BC.

Citation Format: Brasó-Maristany F, Griguolo G, Llombart-Cussac A, Pascual T, Paré L, Bermejo B, Oliveira M, Morales S, Martinez N, Vidal M, Pernas S, Lopez R, Muñoz M, Galvan P, Garau I, Manso L, Alarcón J, Martínez E, Villagrasa P, Cortés J, Prat A. Gene signatures and subtype changes during HER2 dual blockade in PAM50 HER2-enriched HER2-positive breast cancer [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr P6-17-07.

Abstract P6-18-18: Phase I trial of eribulin and everolimus in patients with metastatic triple negative breast cancer

Background: Alteration of PI3K/Akt/mTOR pathway is the most common genomic abnormality detected in triple negative breast cancer (TNBC). Everolimus acts synergistically with eribulin in inducing apoptosis in TNBC cell lines and xenografts in our preclinical study. This phase I trial was designed to test the safety and tolerability of combining eribulin and everolimus in patients (pts) with metastatic TNBC.

Methods: The overall objective of this study was to describe the safety and toxicities of the combination. The secondary objective was to assess activity based on response rate (RR) and progression free survival (PFS). Eligibility criteria included pts with metastatic TNBC, ECOG 0-2, 0-3 lines of prior chemotherapy in metastatic setting, and prior treatment with anthracycline and/or taxane therapy. The study utilized the toxicity equivalence range (TEQR) design with a target equivalence range for dose-limiting toxicities (DLTs) of 0.20-0.35. The recommended phase 2 dose (RP2D) will be the dose closest to the target of 0.25 below 0.51 based on isotonic regression.Three dosing levels of the combinations were tested: level A1 (everolimus 5mg daily; eribulin 1.4 mg/m2 days 1, 8 every 3 weeks), level A2 (everolimus 7.5mg daily; eribulin 1.4 mg/m2, days 1, 8 every 3 weeks), level B1(everolimus 5mg daily; eribulin 1.1 mg/m2 days 1, 8 every 3 weeks). Nanostring RNA analysis and genomic mutation analysis were conducted in 16 pts with available tumor tissue.

Results: A total of 27 pts were enrolled. Median age was 55 years (range 36-76). Two pts were ineligible due to HER2+ on repeat biopsy and were only included in the toxicity analysis. Dose level B1 (everolimus 5mg daily and eribulin 1.1 mg/m2 days 1, 8 every 3 weeks) was determined to be the RP2D doses. The DLTs were neutropenia, stomatitis and hyperglycemia. Across all cycles, 59% (16/27) had a ≥ Gr3 toxicity attributed to treatment at the possible or above level. 44% (12/27) had Gr3 heme-toxicities. The most common toxicities were ≥ Gr3 neutropenia (10 pts), Gr3 lymphopenia (6 pts) and ≥ Gr3 leukopenia (7 pts). 33% (9/27) had Gr3 non-heme toxicities. The most common were Gr3 stomatitis (3 pts), Gr3 hyperglycemia (3 pts) and Gr3 fatigue (5 pts). The median number of cycles completed was 4 (0-8). 68% (17/25) had a dose modification or hold, 14 of 25 (56%) were for eribulin and 15 of 25 (60%) were for everolimus. Of 25 eligible pts, 8 (32%) achieved a best response as partial response, 11 (44%) had stable disease and 6 (24%) had progression. 80% (20/25) experienced progression by RECIST or showed clinical progression, and the median time to progression was 2.7 mo (95% CI (2.2, 4.6)). At the time of this analysis, 16 participants had died, median OS was 6.3 mo (95% CI (5.3, undefined)). Two pts are still being followed on treatment. PI3K-Akt-mTOR pathway genes and mutations profiles were studied.

Conclusion: Eribulin 1.1 mg/m2 days 1, 8 and everolimus 5mg daily was defined as the RP2D. Genomic analysis is currently underway to understand the molecular mechanisms of resistance.

Citation Format: Yuan Y, Yost S, Blanchard S, Yin H, Li M, Robinson K, Tang A, Martinez N, Leong L, Somlo G, Tank Patel N, Waisman J, Portnow J, Hurria A, Luu T-H, Mortimer J. Phase I trial of eribulin and everolimus in patients with metastatic triple negative breast cancer [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr P6-18-18.

Abstract P2-13-01: Efficacy of neratinib in hormone receptor-positive patients who initiated treatment within 1 year of completing trastuzumab-based adjuvant therapy in HER2+ early-stage breast cancer: Subgroup analyses from the phase III ExteNET trial

Background: The international, randomized, placebo-controlled phase III ExteNET trial showed that 1 year (yr) of neratinib 240 mg/day after trastuzumab-based adjuvant therapy significantly improved invasive disease-free survival (iDFS) in 2840 patients with early-stage HER2+ breast cancer at 2 yr (hazard ratio 0.67; 95% CI 0.50–0.91; p=0.009) [Chan 2016] and 5 yr (hazard ratio 0.73; 95% CI 0.57-0.92; p=0.008) [Martin 2017]. A prespecified subgroup analysis by hormone receptor (HR) status suggested enhanced efficacy with neratinib in patients with HR+ (2-yr hazard ratio 0.51; 95% CI 0.33–0.77) vs. HR– tumors (2-yr hazard ratio 0.93; 95% CI 0.60–1.43). The efficacy of neratinib was also greater in patients who initiated treatment within 1 yr of prior trastuzumab compared with those who started neratinib later. The European Medicines Agency's Committee for Medicinal Products for Human Use recently recommended neratinib for use in patients with HR+ tumors who initiate treatment within 1 yr of completing trastuzumab-based adjuvant therapy. Subgroup analyses from ExteNET examining iDFS benefits in this patient population are presented here.

Methods: Patients with early-stage HER2+ breast cancer who completed trastuzumab-based (neo)adjuvant therapy were assigned to oral neratinib 240 mg/day or placebo for 1 yr. Randomization was stratified by HR status (determined locally before trial entry), nodal status, and trastuzumab regimen. Endocrine therapy was allowed in patients with HR+ disease. The primary endpoint, iDFS, was tested by 2-sided log-rank test and hazard ratios (95% CI) were estimated using Cox proportional hazards models. Kaplan-Meier methods were used to estimate iDFS rates. Secondary endpoints were DFS-DCIS, time to distant recurrence, distant DFS, and CNS recurrences. The primary analysis was conducted at 2 yr, and a sensitivity analysis conducted at 5 yr. Clinicaltrials.gov:NCT00878709.

Results: Of the 2840 patients (neratinib, n=1420; placebo, n=1420), 1631 (57%) had HR+ disease (neratinib, n=816; placebo, n=815). Most (93%) HR+ patients were receiving endocrine therapy at baseline. 1334 of 1631 (82%) patients with HR+ tumors were randomized to start neratinib within 1 yr of last trastuzumab dose (neratinib, n=670; placebo, n=664). iDFS benefits from neratinib in this population are shown in the table. Secondary endpoints were also improved with neratinib vs. placebo in this population. Safety data in this subset will be presented at the meeting.

Table. iDFS in patients with an interval between last trastuzumab dose and randomization of ≤1 yr

 HR+ population (N=1334)ITT population (N=2297)  Hazard ratiob  Hazard ratiob  Δ, %a(95% CI)P-valueΔ, %a(95% CI)P-value2-yr analysisc+4.50.490.002+2.90.630.006  (0.30–0.78)  (0.45–0.88) 5-yr analysisd+5.10.580.002+3.20.700.006  (0.41–0.82)  (0.54–0.90) aDifference in iDFS rates between neratinib vs. placebo; bNeratinib vs. placebo; cData cut-off: July 2014; dData cut-off: March 2017

Conclusions: Neratinib may have enhanced and sustained efficacy in patients with HR+ disease who initiate treatment within 1 yr of trastuzumab-based adjuvant therapy.

Citation Format: Gnant M, Martin M, Holmes F-A, Jackisch C, Chia SK, Iwata H, Moy B, Martinez N, Mansi J, Morales S, Ruiz-Borrego M, von Minckwitz G, Buyse M, Delaloge S, Bhandari M, Murias Rosales A, Galeano T, Fujita T, Luczak A, Barrios CH, Saura C, Rugo HS, Chien J, Johnston SR, Spencer M, Xu F, Barnett B, Chan A, Ejlertsen B. Efficacy of neratinib in hormone receptor-positive patients who initiated treatment within 1 year of completing trastuzumab-based adjuvant therapy in HER2+ early-stage breast cancer: Subgroup analyses from the phase III ExteNET trial [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr P2-13-01.

Abstract P6-17-08: Dynamics of tumor-infiltrating lymphocytes (TILs) during neoadjuvant dual HER2 blockade in HER2-positive (HER2+) breast cancer in the absence of chemotherapy

Background: TILs in HER2+ breast cancer (BC) predict 1) prognosis in early setting, 2) complete pathological response (pCR) following neoadjuvant antiHER2-based therapy and 3) response to trastuzumab and pembrolizumab in the metastatic setting. However, less is known regarding changes in TILs during antiHER2-based treatment.

Methods: Stromal TILs where evaluated centrally using H/E slides in tumor samples from the PAMELA (NCT01973660) neoadjuvant phase II trial. Briefly, 151 women with HER2+ BC were treated with lapatinib and trastuzumab, and hormonal therapy if HR positive, for 18 weeks. TIL levels were determined at baseline (n=148), after 2 weeks of treatment (n=134) and at surgery (n=137). Expression of 560 genes, including immune-related genes (e.g. CD8A, CD4, PD1 and PDL1) was measured at the same timepoints (baseline n=151, 2-weeks n=144, surgery n=144) using the nCounter platform. Intrinsic subtyping at baseline was determined using the PAM50 gene expression predictor. Changes in TILs between 2 time-points were determined by paired t-tests. Correlation of TILs with gene expression was assessed by quantitative SAM analysis using a False Discovery Rate <1%. All statistical tests were two-sided and considered significant when p<0.05. All statistical analyses were carried out using the R software.

Results: Compared to baseline, a significant increase in TILs was observed at week 2 in HR- (p<0.001) and HER2-enriched (HER2-E) tumors (p=0.001), but not in HR+ (p=0.133) and non-HER2-E tumors (p=0.067). Within HR- and HER2-E tumors, increase in TILs at week 2 from baseline was observed regardless of pathological response at surgery (pCR and HR- [p=0.008]; RD and HR- [p=0.037]; pCR and HER2-E [p=0.010]; RD and HER2-E [p=0.056]). Compared to week 2, a significant decrease in TILs at surgery was observed in HR- (p=0.002) and HER2-E (p=0.003) tumors, but not in HR+ (p=0.616) and non-HER2-E tumors (p=0.578). Within HR- and HER2-E tumors, a significant decrease in TILs between week 2 and surgery was observed in tumors achieving pCR (p=0.004 and p=0.005), while, in tumors not achieving pCR, no significant tendency was observed (26.4% and 33.0% of tumors showed an increase and a decrease of TILs between week 2 and surgery). Nonetheless, the vast majority of residual tumors (non-pCR) at surgery had TILs above ≥5%: 34.3% 5-10%, 21.0% 10-20%, 15.2% 20-40% and 11.4% ≥40%. Finally, TILs scoring was found highly enriched (FDR<1%) for immune-related genes tracking activated CD8 T-cells (i.e. CD8A, CD3G, LAG3 and PD1). Expression of these immune genes consistently correlated with TIL levels across the 3 time-points.

Conclusions: In early HER2+ BC, a general increase in TILs is observed following 2 weeks of dual HER2 blockade. This observation is mostly observed in HR- and HER2-E subtype, but regardless of pathological response at surgery. After 2 weeks of treatment, TILs consistently decrease in patients achieving a pCR, whereas two main patterns of TILs expression are observed in patients with residual disease at surgery. Nonetheless, most residual tumors at surgery are inflamed (i.e. TILs ≥5%) and might be good candidates for clinical trials evaluating adjuvant immune checkpoint inhibitors.

Citation Format: Griguolo G, Holgado E, Cortés J, Fasani R, Pascual T, Paré L, Bermejo B, Oliveira M, Morales S, Martinez N, Vidal M, Pernas S, Lopez R, Muñoz M, Galvan P, Garau I, Manso L, Alarcón J, Martínez E, Villagrasa P, LLombart-Cussac A, Prat A, Nuciforo P. Dynamics of tumor-infiltrating lymphocytes (TILs) during neoadjuvant dual HER2 blockade in HER2-positive (HER2+) breast cancer in the absence of chemotherapy [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr P6-17-08.

ICRP Publication 138: Ethical Foundations of the System of Radiological Protection

Abstract –

Despite a longstanding recognition that radiological protection is not only a matter of science, but also ethics, ICRP publications have rarely addressed the ethical foundations of the system of radiological protection explicitly. The purpose of this publication is to describe how the Commission has relied on ethical values, either intentionally or indirectly, in developing the system of radiological protection with the objective of presenting a coherent view of how ethics is part of this system. In so doing, it helps to clarify the inherent value judgements made in achieving the aim of the radiological protection system as underlined by the Commission in Publication 103. Although primarily addressed to the radiological protection community, this publication is also intended to address authorities, operators, workers, medical professionals, patients, the public, and its representatives (e.g. NGOs) acting in the interest of the protection of people and the environment. This publication provides the key steps concerning the scientific, ethical, and practical evolutions of the system of radiological protection since the first ICRP publication in 1928. It then describes the four core ethical values underpinning the present system: beneficence/ non-maleficence, prudence, justice, and dignity. It also discusses how these core ethical values relate to the principles of radiological protection, namely justification, optimisation, and limitation. The publication finally addresses key procedural values that are required for the practical implementation of the system, focusing on accountability, transparency, and inclusiveness. The Commission sees this publication as a founding document to be elaborated further in different situations and circumstances.

Ranking of Apparent Area for Different Shapes of Equal Area

36 figures of equal area but different form made up six form classes: triangles, quadrilaterals, polygons, ellipses, stars and irregular figures. 24 students presented with each set one at a time were asked to rank the figures from largest to smallest in perceived area. Next these Ss ranked sets including figures from the different shape classes, the sets being formed on the basis of ranks in the first task. Kendall's W and Friedman's χr2 were significant for rankings within all sets suggesting consistent and differentiated influences of form on apparent area. Significant negative correlations between figure perimeter and ranks of estimated area in Exp. 1 and their absence in Exp. 2 suggested perimeter is related to apparent area with only certain sets of figures.

The effect of pH on the dynamics of natural membranes

Pure phospholipids and membrane fragments from bacterial cells living under various conditions were studied against the influence of the surrounding acidity on the internal dynamics. For that we compared mean square displacements extracted from elastic incoherent neutron scattering data, measured both at low and at neutral pH, of the phospholipids 1,2-dimyristoyl-sn-glycero-3-phosphocholine and of samples from neutralophilic and acidophilic micro-organisms (some being hyperthermophilic and others mesophilic). The lipids showed a slight shift in the phase transition temperature of about 4 degrees under pH variation and became slightly more mobile at lower pH. The membrane fragments not used to extreme acidic conditions were significantly more sensitive to variations in the pH values, whereas the acidophilic and -tolerant samples were much less influenced by this parameter. They presented the higher softness at low pH, which was closer to their native condition. Such findings might be a hint for adaptation mechanisms to different acidity conditions.

Abstract OT1-05-02: A phase II clinical trial of the combination of pembrolizumab and selective androgen receptor modulator GTx-024 in patients with advanced androgen receptor positive triple negative breast cancer

Background: Androgen receptor (AR) targeted therapy and immunotherapy represent one of the most promising strategies for metastatic triple negative breast cancer (mTNBC), which accounts for 15-20% of all breast cancers. As a nonsteroidal selective androgen receptor modulator (SARM), GTx-024 demonstrated preclinical activity in AR+ TNBC PDX model. Pembrolizumab is a highly selective humanized monoclonal antibody of the programmed cell death 1 receptor (PD-1). The complementary modes of action and low potential for overlapping toxicity make the combination promising in patients with AR+ mTNBC.

Trial Design: This is an open-label Phase 2 study for AR+ mTNBC. Eligible participants receive pembrolizumab 200mg IV every 3 weeks in combination with GTx-024 18mg po daily.

Eligibility Criteria: Eligible patients must have AR+ (>10%, 1+ by IHC) TNBC; failed up to 2 lines of therapy in metastatic setting; and have measurable disease per RECIST1.1. Patients are excluded if they have had prior checkpoint inhibitors or AR targeted agents. Patients with current or prior use of testosterone, testosterone-like agents, androgenic compounds, or anti-androgens (including systemic steroids and immunosuppressive medications)are excluded, as well as current or prior history of noninfectious pneumonitis requiring systemic steroid therapy.

Specific Aims: The primary objective is to evaluate the safety/tolerability of GTx-024 and pembrolizumab and determine the response rate (CR or PR via RECIST 1.1) in patients with advanced AR+ TNBC. We will use clinical benefit rate (CBR), duration of response (DOR), PFS, and OS to test the efficacy of this novel drug combination.

Statistical Design: A Simon's MiniMax two-stage Phase 2 design will be utilized. Based on the previously reported response rate associated with single agent pembrolizumab (19%), we consider a response rate of 19% for the combination as discouraging, and a 39% response rate as encouraging. As a result, we will initially accrue 15 patients (including 6 patients from safety lead-in treated at the tolerable dose). If 2 or fewer patients respond, we will stop accrual for futility. Otherwise, the study will accrue an additional 14 patients for a total of 29 patients. With 29 patients, if only 8 or fewer respond (≤27.6%), the study will be considered discouraging unless secondary evidence of clinical benefit is substantial. With more than 8 patients responding out of the 29 patients, the combination would be considered promising. This design has 85% power to declare a true response rate of 39% as promising (power), and a 10% probability of declaring a true 19% response rate as encouraging (type I error). The probability of early termination if the true response rate is 19% is 44%.

Target Accrual: 29

Study Contact: Yuan Yuan MD PhD, City of Hope Comprehensive Cancer Center; Duarte, CA 91030; Email: yuyuan@coh.org

Citation Format: Yuan Y, Frankel P, Synold T, Lee P, Yost S, Martinez N, Tang A, Mendez B, Schmolze D, Apple S, Hurria A, Waisman J, Somlo G, Tank N, Sedrak M, Mortimer J. A phase II clinical trial of the combination of pembrolizumab and selective androgen receptor modulator GTx-024 in patients with advanced androgen receptor positive triple negative breast cancer [abstract]. In: Proceedings of the 2017 San Antonio Breast Cancer Symposium; 2017 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2018;78(4 Suppl):Abstract nr OT1-05-02.