Abstract P2-02-14: Circulating tumor DNA predicts clinical outcome in early stage triple negative breast cancer

Background- Triple negative breast cancer (TNBC) is the most aggressive subtype of breast cancer as these patients have the highest risk of recurrence and death. Only 35% of TNBC patients achieve a pathologic complete response (pCR) following neoadjuvant chemotherapy. Patients who do not achieve pCR have a 27% risk of distant recurrence and ultimate death at 3 years compared to 9% for pCR. Unidentified micrometastases are responsible for ultimate overt progression and death. Developing strategies to identify patients with minimal residual disease following curative treatment is an unmet need. Circulating tumor DNA (ctDNA) can characterize and monitor advanced cancers. In this study, we sought to assess if ctDNA can predict clinical outcome in TNBC.

Methods-Biospecimens were obtained from patients with stages II and III TNBC enrolled on a neoadjuvant trial (NCT02124902). Patients have a research biopsy and plasma for ctDNA collected at baseline, cycle 1 day 3, definitive surgery for those with residual disease, and at recurrence for those who relapse. Plasma for ctDNA is also collected every 6 months for 5 years after treatment. Patients receive docetaxel and carboplatin every 3 weeks X 6 cycles. Surgery is 3-5 weeks after chemotherapy. Six patients' serial tumor samples and germline DNA were studied by whole exome sequencing. The median sequencing depth was 90.13x. Sequencing was performed on samples with high cellularity (≥50%). All 6 patients also had serial ctDNA analyzed using Swift Biosciences Accel-Amplicon™ 56G Oncology Panel v2. After identifying somatic mutations in each breast tumor series, we determined the subset of mutations that intersected with the regions targeted by the Swift 56 gene panel. We then evaluated whether corresponding mutations could be detected in ctDNA, and if ctDNA predicted clinical outcome.

Results-Four of the 6 patients were non-pCR with residual disease following chemotherapy. We identified 627 somatic variants by exome analysis that were called by at least two somatic variant callers and passed additional quality filtering steps. Of these, 10 variants overlapped with the Swift panel. TP53 variants were identified in all 6 patients' tumor tissue samples. At least one TP53 variant was identified in 4 patients' baseline pre-chemotherapy ctDNA samples. Both pCR patients had either no detectable ctDNA TP53 mutations (NTN007-ref. in baseline tumor tissue was 19.58% variant allele frequency [VAF]); or clearance of ctDNA following chemotherapy from 4.45% VAF at baseline to 0.06% following chemotherapy (NTN004-ref. in baseline tumor tissue 37.34% VAF). Three non-PCR patients had persistent TP53 mutations in ctDNA during the treatment course. One non-pCR patient did not have detectable mutations in ctDNA. The only patient with recurrent disease whose ctDNA TP53 mutation persisted during the treatment course (baseline VAF-1.65%, cycle 1 day 3-0.78%, definitive surgery-0.09%), was found to have a higher ctDNA VAF at recurrence (29.55%).

Conclusion-In this pilot study, mutation tracking by ctDNA is sensitive and distinguishes pCR from non-pCR in TNBC patients receiving neoadjuvant chemotherapy. ctDNA also identifies recurrence following curative therapy. Evaluating ctDNA as a biomarker of outcome in TNBC is warranted.

Citation Format: Ademuyiwa F, Feng Y-Y, Skidmore Z, Kunisaki J, Walker J, Fulton R, Krysiak K, Skinner T, Weilbaecher K, Ma C, Griffith O, Griffith M. Circulating tumor DNA predicts clinical outcome in early stage 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 P2-02-14.

[Acupuncture covered by statutory health insurance in Germany : An observational study based on claims data]

BACKGROUND

The coverage for acupuncture for chronic lower back or knee pain by the statutory health insurance was introduced in 2007. The aim of this study was to investigate characteristics of patients and providers of acupuncture and temporal and regional trends in the utilization of acupuncture.

METHODS

This retrospective observational study used anonymized statutory health insurance claims data from a sample of roughly four million subjects. The sample is representative of the German population regarding age and gender in 2013.

RESULTS

Lower back pain was the most common coded indication (86%) for billing acupuncture. Women were more often treated with acupuncture than men; the mean age was 61.1 years. For 63% acupuncture was billed in 2014 for the first time, 37% already had an acupuncture treatment in 2012 or 2013. Premature termination (<6 sessions) was observed in 14% of all insurants receiving acupuncture for the first time in 2014 for knee pain and in 21% of those with back pain. Overall there was a statistically significant decrease in the utilization of acupuncture from 2008 to 2015. Regional differences between East and West Germany and city states were observed. Half of all acupuncture treatments in 2014 were provided by 11% of all physicians who billed acupuncture at least once.

DISCUSSION

Higher utilization of acupuncture by women reflects the epidemiology of back and knee pain and their preference for alternative complementary medicine. On the one hand, the large proportion of patients treated repeatedly with acupuncture suggests perceived benefits. On the other hand, provision of acupuncture services is decreasing continuously and a relevant proportion of subjects are terminating treatment prematurely.

Correction to: Abstracts : 29th European Congress of Pathology

Due to an error with the registration system, the following abstract was regrettably omitted from the Poster Sessions. The abstract should have been included as PS-10-021 and displayed on page S166.

Does regional loss of bone density explain low trauma distal forearm fractures in men (the Mr F study)?

The pathogenesis of low trauma wrist fractures in men is not fully understood. This study found that these men have lower bone mineral density at the forearm itself, as well as the hip and spine, and has shown that forearm bone mineral density is the best predictor of wrist fracture.

INTRODUCTION

Men with distal forearm fractures have reduced bone density at the lumbar spine and hip sites, an increased risk of osteoporosis and a higher incidence of further fractures. The aim of this case-control study was to investigate whether or not there is a regional loss of bone mineral density (BMD) at the forearm between men with and without distal forearm fractures.

METHODS

Sixty-one men with low trauma distal forearm fracture and 59 age-matched bone healthy control subjects were recruited. All subjects underwent a DXA scan of forearm, hip and spine, biochemical investigations, health questionnaires, SF-36v2 and Fracture Risk Assessment Tool (FRAX). The non-fractured arm was investigated in subjects with fracture and both forearms in control subjects.

RESULTS

BMD was significantly lower at the ultradistal forearm in men with fracture compared to control subjects, in both the dominant (mean (SD) 0.386 g/cm² (0.049) versus 0.436 g/cm² (0.054), p < 0.001) and non-dominant arm (mean (SD) 0.387 g/cm² (0.060) versus 0.432 g/cm² (0.061), p = 0.001). Fracture subjects also had a significantly lower BMD at hip and spine sites compared with control subjects. Logistic regression analysis showed that the best predictor of forearm fracture was ultradistal forearm BMD (OR = 0.871 (0.805-0.943), p = 0.001), with the likelihood of fracture decreasing by 12.9% for every 0.01 g/cm² increase in ultradistal forearm BMD.

CONCLUSIONS

Men with low trauma distal forearm fracture have significantly lower regional BMD at the ultradistal forearm, which contributes to an increased forearm fracture risk. They also have generalised reduction in BMD, so that low trauma forearm fractures in men should be considered as indicator fractures for osteoporosis.

Abstract 664: Analytical validation and clinical utility of an immunohistochemical PD-L1 diagnostic assay for treatment with durvalumab in urothelial carcinoma patients

Background: A high quality programmed cell death ligand-1 (PD-L1) diagnostic may help to identify patients (pts) most likely to respond to anti-PD-L1/programmed cell death-1 (PD-1) therapy. Here we describe a PD-L1 immunohistochemical (IHC) diagnostic test developed for urothelial carcinoma (UC) pts treated with durvalumab.

Methods: The IHC assay uses an anti-human PD-L1 rabbit mAb optimized for detection of both tumor cell (TC) and tumor-associated immune cell (IC) PD-L1 expression with the OptiView DAB IHC Detection Kit on the automated VENTANA BenchMark ULTRA platform. The assay was validated for intended use in UC formalin-fixed, paraffin-embedded samples in a series of studies that addressed sensitivity, specificity, robustness and precision and implemented in Study CD-ON-MEDI4736-1108 (NCT01693562). Pts were evaluated using the VENTANA PD-L1 (SP263) Assay at a prespecified PD-L1 expression cut-off. Efficacy was analyzed in pts with PD-L1 low/negative (defined as TC &lt;25% and IC &lt;25%) UC and in pts with PD-L1 high (defined as TC ≥25% or IC ≥25%) UC.

Results: The VENTANA PD-L1 (SP263) Assay met all the predefined acceptance criteria (average positive agreement and average negative agreement &gt;85%), showing analytical specificity, sensitivity and precision. It demonstrated ≥97% and ≥85% inter-reader precision agreement for TC and IC respectively. For intra-reader precision, it demonstrated &gt;96% and &gt;87% agreement for TC and IC respectively. For intra-day performance, the assay demonstrated ≥96% agreement for TC and IC and for inter-day performance, it demonstrated ≥98% and 100% agreement for TC and IC respectively. Precision studies for inter-antibody lot, inter-detection kit lot and intra-platform demonstrated &gt;97% agreement for both TC and IC. Inter-laboratory testing was performed at 3 external laboratories and demonstrated an overall agreement rate of 92.3%. The VENTANA PD-L1 (SP263) Assay was implemented in Study CD-ON-MEDI4736-1108 and durvalumab demonstrated clinical activity and durability of response in both PD-L1 high and PD-L1 low/negative subgroups, yet with different response rates. In addition, given the high negative predictive value of the assay, it is especially helpful in evaluating the likelihood of response to durvalumab; pts who were classified as PD-L1 high with the VENTANA PD-L1 (SP263) Assay tended to have a higher objective response rate per RECIST v1.1 than pts who were PD-L1 low/negative.

Conclusions: These data show that determination of PD-L1 expression in TC and IC in UC pts using the VENTANA PD-L1 (SP263) Assay is precise and highly reproducible and highlight the utility of the assay in a clinical setting. The VENTANA SP263 Assay is especially helpful in informing pts and physicians on the likelihood of response to durvalumab, but not for the purpose of restricting treatment to only PD-L1 high pts.

Citation Format: M Zajac, A M. Boothman, Y Ben, A Gupta, J Antal, X Jin, A Nielsen, G Manriquez, C Barker, P Wang, P Patil, N Schechter, M Rebelatto, J Walker. Analytical validation and clinical utility of an immunohistochemical PD-L1 diagnostic assay for treatment with durvalumab in urothelial carcinoma patients [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 664. doi:10.1158/1538-7445.AM2017-664

Abstract 656: PD-L1 expression in primary lesions vs metastatic sites and by demographics in advanced urothelial carcinoma samples

Background: Determination of programmed cell death ligand-1 (PD-L1) expression levels in tumors may help physicians understand which patients (pts) are most likely to respond to anti-PD-1/PD-L1 therapies in urothelial carcinoma (UC). Understanding the impact of different sample types and demographics on PD-L1 expression is important to determine suitability of tumor biopsies for testing.

Methods: As of July 24, 2016, 363 pts screened in the UC cohort of Study CD-ON-MEDI4736-1108 (NCT01693562) had tissue available for analysis and 47 pts had provided paired primary and metastatic samples. FFPE samples were tested in a central laboratory with the VENTANA PD-L1 (SP263) Assay using a BenchMark ULTRA instrument. Pts were classified as having either PD-L1 high (PD-L1 expression ≥25% either on tumour cells [TC] or immune cells [IC]) or PD-L1 low/negative (&lt;25% on TC and IC) tumors. PD-L1 high prevalence was reported in primary vs metastatic sites, and by age, sex and race.

Results: PD-L1 status was evaluable for 332/363 (91.5%) pts (175/332 [52.7%] PD-L1 high and 157/332 [47.3%] PD-L1 low/negative) whose UC specimens were tested (intent to diagnose [ITD] population). Overall percentage agreement between paired primary and metastatic samples, based on combined TC/IC scoring ≥25%, was 74.5% (95% CI 59.7 - 86.1%). In the ITD population, using only the samples from which patient PD-L1 expression status was determined, PD-L1 high prevalence in primary and metastatic samples was 57.1% and 50.9% respectively (p=0.343, not significant). The proportion of pts with PD-L1 high status was not enriched in any demographic group (Table).

Conclusions: Initial data from UC pts in Study 1108 showed similar PD-L1 high prevalence in primary and metastatic lesions and good concordance between paired primary and metastatic samples. These results build optimism that samples obtained from either location could be used to determine PD-L1 status. Further data are needed to confirm these findings.

Patients screened for UC cohort with evaluable PD-L1 result - ITD population (n = 332)ParameterPD-L1 high, n (%)P valueAge, years&lt;65 (n=131)73 (55.7%)0.438≥65 (n=201)102 (50.8%)SexMale (n=236)127 (53.8%)0.610Female (n=96)48 (50.0%)RaceAsian (n=52)23 (44.2%)Asian vs White: 0.406Black or African American (n=10)6 (60.0%)White (n=218)113 (51.8%)Other (n=9)4 (44.4%)

Citation Format: M Zajac, A M. Boothman, Y Ben, A Gupta, X Jin, J Antal, A Sharpe, M Scott, M Rebelatto, J Walker. PD-L1 expression in primary lesions vs metastatic sites and by demographics in advanced urothelial carcinoma samples [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 656. doi:10.1158/1538-7445.AM2017-656

Affective concordance in couples: a cross-sectional analysis of depression and anxiety consultations within a population of 13,507 couples in primary care

BACKGROUND

Depression and anxiety are common and have a significant impact on the individual and wider society. One theory proposed to explain a heightened risk for depression and anxiety is affective concordance in couples (e.g. influence of shared mood states, shared health beliefs). Whilst research has shown concordance for severe psychiatric illnesses and general mood in couples, little attention has been given to concordance for common psychiatric conditions such as depression and anxiety. The aims of this study were to test affective concordance in couples and examine potential influences on concordance.

METHODS

Study design is a 1-year cross-sectional study of anxiety and depression consultations in primary care. Data were obtained from a validated primary care database of recorded consultations. Outcome was the presence of an anxiety or depression Read Code (GP recorded reason for consultation) in the female (within the couple dyad), and exposure was a recorded Read Code of anxiety or depression in the male. Logistic regression was used to test associations with odds ratios (OR) and 95% confidence intervals (95% CI) reported. Statistical adjustment was carried out on potential influences of concordance; age, environment (deprivation), healthcare behaviour (consultation frequency), and comorbidity.

RESULTS

A population of 13,507 couples were identified in which 927 people consulted for anxiety and 538 for depression. Logistic regression showed a 3 times increase in odds of an anxiety consultation in females if their male partner had also consulted OR 2.98 (95% CI 2.15 to 4.13). For depression females were over 4 times the odds of consulting if their male partner had also consulted OR 4.45 (95% CI 2.79 to 7.09). Adjustment within a multivariable model showed some reduction in odds; concordant anxiety was reduced to 2.5 times odds OR 2.48 (95%CI 1.76 to 3.50) and depression reduced to OR 3.39 (2.07 to 5.54).

CONCLUSION

Results show significant associations for affective concordance in couples. Factors influencing concordance are comorbidity and environmental factors, however reasons for deciding to consult (positive or negative) are unknown. This study highlights the patients' social context as a factor in consultations for anxiety and depression and gives support to the consideration of the patient's household as an influence on mental health.

Microbiological problems and biofilms associated with Mycobacterium chimaera in heater-cooler units used for cardiopulmonary bypass

The role of heater-cooler units (HCUs) in the transmission of Mycobacterium chimaera during open heart surgery has been recognized since 2013. Subsequent investigations uncovered a remarkable global outbreak reflecting the wide distribution of implicated devices. HCUs are an essential component of cardiopulmonary bypass operations and their withdrawal would severely affect capacity for life-saving cardiac surgery. However, studies have demonstrated that many HCUs are contaminated with a wide range of micro-organisms, including M. chimaera and complex biofilms. Whole genome sequencing of M. chimaera isolates recovered from one manufacturer's HCUs, worldwide, has demonstrated a high level of genetic similarity, for which the most plausible hypothesis is a point source contamination of the devices. Dissemination of bioaerosols through breaches in the HCU water tanks is the most likely route of transmission and airborne bacteria have been shown to have reached the surgical field even with the use of ultraclean theatre ventilation. Controlling the microbiological quality of the water circulating in HCUs and reducing biofilm formation has been a major challenge for many hospitals. However, enhanced decontamination strategies have been recommended by manufacturers, and, although they are not always effective in eradicating M. chimaera from HCUs, UK hospitals have not reported any new cases of M. chimaera infection since implementing these mitigation strategies. Water safety groups in hospitals should be aware that water in medical devices such as HCUs may act as a vector in the transmission of potentially fatal water-borne infections.

Brain Development in Fetuses of Mothers with Diabetes: A Case-Control MR Imaging Study

BACKGROUND AND PURPOSE

Offspring exposed to maternal diabetes are at increased risk of neurocognitive impairment, but its origins are unknown. With MR imaging, we investigated the feasibility of comprehensive assessment of brain metabolism (¹H-MRS), microstructure (DWI), and macrostructure (structural MRI) in third-trimester fetuses in women with diabetes and determined normal ranges for the MR imaging parameters measured.

MATERIALS AND METHODS

Women with singleton pregnancies with diabetes (n = 26) and healthy controls (n = 26) were recruited prospectively for MR imaging studies between 34 and 38 weeks' gestation.

RESULTS

Data suitable for postprocessing were obtained from 79%, 71%, and 46% of women for ¹H-MRS, DWI, and structural MRI, respectively. There was no difference in the NAA/Cho and NAA/Cr ratios (mean [SD]) in the fetal brain in women with diabetes compared with controls (1.74 [0.79] versus 1.79 [0.64], P = .81; and 0.78 [0.28] versus 0.94 [0.36], P = .12, respectively), but the Cho/Cr ratio was marginally lower (0.46 [0.11] versus 0.53 [0.10], P = .04). There was no difference in mean [SD] anterior white, posterior white, and deep gray matter ADC between patients and controls (1.16 [0.12] versus 1.16 [0.08], P = .96; 1.54 [0.16] versus 1.59 [0.20], P = .56; and 1.49 [0.23] versus 1.52 [0.23], P = .89, respectively) or volume of the cerebrum (243.0 mL [22.7 mL] versus 253.8 mL [31.6 mL], P = .38).

CONCLUSIONS

Acquiring multimodal MR imaging of the fetal brain at 3T from pregnant women with diabetes is feasible. Further study of fetal brain metabolism in maternal diabetes is warranted.