Assessing the real-world (RW) efficacy and toxicity of docetaxel (D) for the treatment of metastatic castrate sensitive prostate cancer (mCSPC): A single institution experience

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Background: While D has been shown to prolong survival and improve quality of life in men with mCSPC in clinical trial settings, less is known about its effectiveness in the RW setting. Furthermore, it is uncertain whether the timing of D affects toxicity and outcome. We aimed to identify effectiveness and toxicity outcomes as well as patient (pt) characteristics and prescribing patterns at our institution. Methods: In this retrospective chart analysis, we identified 70 pts with mCSPC who were treated with D between June 2014 and September 2018 at an academic cancer centre in Toronto. The main outcomes studied included time to castrate resistance (TCR), change in PSA, number of cycles completed, and rates of febrile neutropenia (FN). We also analyzed pt subgroups including pts starting D <50 days after the start of androgen deprivation therapy (ADT) versus those starting >50 days after ADT initiation. Results: The median age of our pts was 69 (IQR: 64-74). The median follow-up time was 598 days. 79% of pts had high volume disease per CHAARTED criteria, 73% had de novo metastatic disease and 85% had bone-only disease. The median TCR from the start of ADT was 12.3 months. The median change in PSA from pre-ADT to post-D nadir was 99%. The mean D dose intensity was 86% of the ideal dose and 91% of pts completed all 6 cycles of D. 11% of pts were diagnosed with FN during treatment. 6% of pts required treatment delays and 19% required toxicity-related dose reductions. Subgroup analysis showed that patients (n=41) who received D >50 days from the start of ADT did not have significant differences in TCR, rates of FN, need for a decrease in dose intensity or treatment delays compared to those starting <50 days after ADT (n=29). Conclusions: D can be delivered safely in RW pts, with low rates of FN, however, there is evidence of an efficacy-effectiveness gap with a shorter TCR compared to that observed in CTs. The timing of D (<50 days vs. >50 days) does not appear to have an impact on outcome or toxicity.

A survey to determine patients’ (pts) opinions of a clinical trial (CT) comparing intermittent (int) versus continuous (cont) androgen receptor signaling inhibitor (ARSi) therapy for the treatment of advanced prostate cancer

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Background: Several therapies have shown a survival benefit and improvements in pt-reported quality of life in metastatic prostate cancer (mPC) including ARSis, such as abiraterone (A) and enzalutamide (E). While both are fairly well tolerated, there is a wide range of side effects associated with them. In addition, both of these medications are costly. The purpose of this study was to obtain pts’ opinions regarding potential participation in a randomized CT comparing int to cont treatment with A and E. Methods: We approached ambulatory pts diagnosed with mPC between August 2018 and October 2018 to complete a questionnaire eliciting their preferences regarding participation in a CT comparing int to cont treatment with A or E. A total of 105 patients completed the survey. We collected information regarding pts’ current/prior therapies, their interest in being treated with an int strategy and reasons for or against participating in a randomized CT with int versus cont treatment. Results: The median age of our pts was 72 years (IQR: 67 -78). 30% of patients had prior experience with an ARSi (A 10%, E 20%). 51% of pts were receiving either A (28%) or E (23%) at the time of the survey. 76% of pts indicated that they would generally be interested (27%) or very interested (49%) in participating in CTs, and 65% of patients were interested (19%) or very interested (46%) in participating in a CT involving int ARSi therapy. The reasons for participating include the prospect of less side effects (49%), less medication burden (39%), and cost-savings (15%). The reasons for not participating include the possibility of the cancer worsening off treatment (55%), the possibility of worse overall survival (48%), and the possibility of developing cancer-related symptoms in the off-phase (39%). Conclusions: The majority of pts surveyed would be interested in participating in a randomized CT that would include int versus cont treatment with an ARSi. In a complementary study, we are surveying oncologists to determine the ideal patient cohort for such a study, as well as acceptable triggers for treatment interruption and resumption.

Personalized use of metronomic cyclophosphamide for DNA repair deficient castration-resistant prostate cancer: A phase II trial

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Background: There is a continued need to identify novel targets for the treatment of metastatic, castration-resistant prostate cancer (mCRPC). DNA damage repair (DDR) aberrations are emerging as such a target: 20%-30% of mCRPCs harbor DDR gene aberrations, rendering tumors particularly sensitive to DNA damaging agents and poly ADP-ribose polymerase inhibitor (PARPi) therapy. 88% of men with DDR deficient mCRPC responded to the PARPi olaparib in a phase II trial, whereas in unselected mCRPC patients the metronomic use of the DNA damaging agent cyclophosphamide (CPA) resulted in response rates of 25-60%. Intriguingly, in randomized phase II trials of unselected ovarian and triple-negative breast cancer (ie tumor types enriched for DDR defects), metronomic CPA alone was as active as metronomic CPA plus the PARPi veliparib. Based on this we hypothesize that DDR deficient mCRPC is particularly sensitive to metronomic CPA. To the best of our knowledge this is the first attempt to utilize metronomic CPA in a personalized manner. Our study has the potential to define metronomic CPA as an affordable and well-tolerated alternative to PARPi therapy in men with DDR deficient mCRPC. Methods: To study if metronomic CPA achieves a similar response rate (ie ≥85%) in DDR deficient mCRPC as seen with olaparib, men with mCRPC progressing after 1-2 lines of systemic therapy will undergo circulating tumor DNA based testing for BRCA1/2 or ATM aberrations. Patients with such aberrations will proceed with metronomic CPA (50 mg po daily). Primary endpoint: RECIST 1.1 and/or ≥50% PSA response rate at 12 weeks. Secondary endpoints include biochemical, radiological and clinical progression-free survival. Applying the Optimal Simon's Two-Stage design, and using a type I error rate of 0.05 and a power of 0.8, in the first stage we plan to enroll 14 patients. If there are ≤10 or fewer responses, the study will be stopped. Otherwise, another 19 patients will be accrued as part of the second stage.

Skull Base 3D Modeling of Rigid Buttress for Gasket-Seal Closure Using Operative Endoscopic Imaging: Cadaveric Feasibility

Surgical defect closure following endonasal transsphenoidal tumor resection is a critical component of procedural success. Three-dimensional (3D) modeling of relevant skull base anatomy during resection can potentially facilitate design of a custom rigid buttress for gasket-seal closure; however, access to conventional cross-sectional imaging intraoperatively is limited and cumbersome. Endoscopic imaging, by contrast, is always available. This work demonstrates the feasibility of 3D modeling of the visible skull base through structure-from-motion photogrammetric postprocessing techniques, providing a suitable template to design a gasket-seal buttress. Additionally, endoscopic 3D reconstruction of skull base surface anatomy may represent a more robust depiction of the surgical defect than is available by conventional 3D modeling with computed tomography, which suboptimally recapitulates very thin bones and mucosal surfaces typical of this regional anatomy.

Soil and water bioengineering: Practice and research needs for reconciling natural hazard control and ecological restoration

Soil and water bioengineering is a technology that encourages scientists and practitioners to combine their knowledge and skills in the management of ecosystems with a common goal to maximize benefits to both man and the natural environment. It involves techniques that use plants as living building materials, for: (i) natural hazard control (e.g., soil erosion, torrential floods and landslides) and (ii) ecological restoration or nature-based re-introduction of species on degraded lands, river embankments, and disturbed environments. For a bioengineering project to be successful, engineers are required to highlight all the potential benefits and ecosystem services by documenting the technical, ecological, economic and social values. The novel approaches used by bioengineers raise questions for researchers and necessitate innovation from practitioners to design bioengineering concepts and techniques. Our objective in this paper, therefore, is to highlight the practice and research needs in soil and water bioengineering for reconciling natural hazard control and ecological restoration. Firstly, we review the definition and development of bioengineering technology, while stressing issues concerning the design, implementation, and monitoring of bioengineering actions. Secondly, we highlight the need to reconcile natural hazard control and ecological restoration by posing novel practice and research questions.

Cost-effectiveness of yoga for managing musculoskeletal conditions in the workplace

Background

Back pain and musculoskeletal conditions negatively affect the health-related quality of life (HRQL) of employees and generate substantial costs to employers.

Aims

To assess the cost-effectiveness of yoga for managing musculoskeletal conditions.

Methods

A randomized controlled trial evaluated an 8-week yoga programme, with a 6-month follow-up, for National Health Service (NHS) employees. Effectiveness in managing musculoskeletal conditions was assessed using repeated-measures generalized linear modelling for the Roland-Morris Disability Questionnaire (RDQ) and the Keele STarT Back Screening Tool. Cost-effectiveness was determined using area-under-the-curve linear regression for assessing HRQL from healthcare and societal perspectives. The incremental cost per quality-adjusted life year (QALY) was also calculated. Sickness absence was measured using electronic staff records at 6 months.

Results

There were 151 participants. At 6 months, mean differences between groups favouring yoga were observed for RDQ [-0.63 (95% CI, -1.78, 0.48)], Keele STarT [-0.28 (95% CI, -0.97, 0.07)] and HRQL (0.016 QALY gain). From a healthcare perspective, yoga yielded an incremental cost-effectiveness ratio of £2103 per QALY. Given a willingness to pay for an additional QALY of £20 000, the probability of yoga being cost-effective was 95%. From a societal perspective, yoga was the dominant treatment compared with usual care. At 6 months, electronic staff records showed that yoga participants missed a total of 2 working days due to musculoskeletal conditions compared with 43 days for usual care participants.

Conclusions

Yoga for NHS employees may enhance HRQL, reduce disability associated with back pain, lower sickness absence due to musculoskeletal conditions and is likely to be cost-effective.

Critical care usage after major gastrointestinal and liver surgery: a prospective, multicentre observational study

BACKGROUND

Patient selection for critical care admission must balance patient safety with optimal resource allocation. This study aimed to determine the relationship between critical care admission, and postoperative mortality after abdominal surgery.

METHODS

This prespecified secondary analysis of a multicentre, prospective, observational study included consecutive patients enrolled in the DISCOVER study from UK and Republic of Ireland undergoing major gastrointestinal and liver surgery between October and December 2014. The primary outcome was 30-day mortality. Multivariate logistic regression was used to explore associations between critical care admission (planned and unplanned) and mortality, and inter-centre variation in critical care admission after emergency laparotomy.

RESULTS

Of 4529 patients included, 37.8% (n=1713) underwent planned critical care admissions from theatre. Some 3.1% (n=86/2816) admitted to ward-level care subsequently underwent unplanned critical care admission. Overall 30-day mortality was 2.9% (n=133/4519), and the risk-adjusted association between 30-day mortality and critical care admission was higher in unplanned [odds ratio (OR): 8.65, 95% confidence interval (CI): 3.51-19.97) than planned admissions (OR: 2.32, 95% CI: 1.43-3.85). Some 26.7% of patients (n=1210/4529) underwent emergency laparotomies. After adjustment, 49.3% (95% CI: 46.8-51.9%, P<0.001) were predicted to have planned critical care admissions, with 7% (n=10/145) of centres outside the 95% CI.

CONCLUSIONS

After risk adjustment, no 30-day survival benefit was identified for either planned or unplanned postoperative admissions to critical care within this cohort. This likely represents appropriate admission of the highest-risk patients. Planned admissions in selected, intermediate-risk patients may present a strategy to mitigate the risk of unplanned admission. Substantial inter-centre variation exists in planned critical care admissions after emergency laparotomies.

Electrical impedance tomography for non-invasive assessment of stroke volume variation in health and experimental lung injury

BACKGROUND

Functional imaging by thoracic electrical impedance tomography (EIT) is a non-invasive approach to continuously assess central stroke volume variation (SVV) for guiding fluid therapy. The early available data were from healthy lungs without injury-related changes in thoracic impedance as a potentially influencing factor. The aim of this study was to evaluate SVV measured by EIT (SVV_EIT) against SVV from pulse contour analysis (SVV_PC) in an experimental animal model of acute lung injury at different lung volumes.

METHODS

We conducted a randomized controlled trial in 30 anaesthetized domestic pigs. SVV_EIT was calculated automatically analysing heart-lung interactions in a set of pixels representing the aorta. Each initial analysis was performed automatically and unsupervised using predefined frequency domain algorithms that had not previously been used in the study population. After baseline measurements in normal lung conditions, lung injury was induced either by repeated broncho-alveolar lavage (n=15) or by intravenous administration of oleic acid (n=15) and SVV_EIT was remeasured.

RESULTS

The protocol was completed in 28 animals. A total of 123 pairs of SVV measurements were acquired. Correlation coefficients (r) between SVV_EIT and SVV_PC were 0.77 in healthy lungs, 0.84 after broncho-alveolar lavage, and 0.48 after lung injury from oleic acid.

CONCLUSIONS

EIT provides automated calculation of a dynamic preload index of fluid responsiveness (SVV_EIT) that is non-invasively derived from a central haemodynamic signal. However, alterations in thoracic impedance induced by lung injury influence this method.

Improving support for smoking cessation in medical oncology patients: A quality improvement initiative

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Background: Smoking cessation is integral to cancer care. Active smoking is associated with increased toxicity of treatment, poorer response to therapy and is associated with worse overall survival. Patients who quit smoking at diagnosis have better survival outcomes. Cancer Care Ontario has aimed to improve rates of smoking screening and referral to smoking cessation programs based on the validated Ottawa model. Methods: We aimed to implement an “opt-out” referral process for recent or current smokers to a smoking cessation program at the Credit Valley Hospital. We aimed to achieve a referral rate of 20%, based on an institutional baseline of 8.5% and a provincially defined target of 20%. Key stakeholders targeted included nursing, administration, physicians, smoking cessation counsellors and patients. Sequential education interventions were delivered to address gaps in patient and provider knowledge; these included grand rounds, an informal lecture and an educational pamphlet. Results: After the initiative was launched, the referral rate increased from 8.5% to 14.3%. The impact of each intervention is summarized in Table 1. Conclusions: Smoking cessation referrals increased with new process but not to target. Patient refusals lead to a low rate of referral, warranting efforts aimed at addressing patient barriers. Future outcome measures may include smoking cessation rates. [Table: see text]

Does the risk of emergency department visits and hospitalizations during systemic therapy for cancer influence patient decisions regarding treatment?

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Background: When different treatments (tx) produce similar prognostic outcomes, other tx attributes such as toxicity may impact tx preferences. We conducted a discrete choice experiment to evaluate how patients’ value the risk of an emergency department visit (ED) or hospitalization during treatment when deciding about chemotherapy. Methods: Patients with breast, head and neck or colorectal cancer who were contemplating, receiving or had previously received systemic treatment were recruited from 2 academic cancer centres in Toronto, Ontario. Each participant completed 10 choice tasks (5 each in the adjuvant and metastatic settings, respectively) from a possible 128 combinations. Each choice task prompted them to choose between two hypothetical systemic therapies, based on 3 attributes (likelihood of benefit, risk of requiring an ED visit and risk of hospitalization during treatment) that varied across 4 levels. Data was analyzed using a multinomial logit model and individual part-worth utility (PWU) values were estimated using hierarchal Bayes routines. Results: Between 06/2015 and 09/2017, 293 patients completed the survey. Most patients were female (76%), had a diagnosis of breast cancer (63%) and were currently receiving systemic therapy (72%). 59% of patients were receiving tx with curative intent. PWU values varied as expected with higher PWUs seen for higher treatment benefit, lower risk of ED visits and lower risk of hospitalization. Treatment benefit was the most important decision attribute in both the adjuvant (59%, 95%CI 57.8-60.1%) and metastatic (67.7%, 95%CI 66.8-68.7%) scenarios, followed by risk of hospitalization (18.8 vs 22.8%) then risk of ED visits (13.5 vs 18.3%). Results were the same when stratified by patient’s own treatment intent. Conclusions: While the risks of hospitalization and ED visits contribute to patient tx preferences, the extent of tx benefit was the most important attribute regardless of treatment intent.

Abstract P5-20-17: Safety of continuing chemotherapy in overt left ventricular dysfunction using antibodies to human epidermal growth factor receptor-2: A retrospective study

Introduction: Trastuzumab is a monoclonal antibody that targets the human epidermal growth factor receptor (HER)-2 and significantly improves survival in HER-2 positive early stage breast cancer. However, trastuzumab is also known to cause cardiotoxicity. Guidelines recommend withholding or discontinuing trastuzumab if left ventricular ejection fraction (LVEF) falls ≥15% from baseline, or to &lt;50%, but there is little evidence to support this strategy. Additionally, premature discontinuation of trastuzumab may lead to poorer cancer outcomes. Trastuzumab cardiotoxicity is frequently reversible, and the use of angiotensin converting enzyme-inhibitors (ACE-I) and beta blockers is highly effective at treating impaired LVEF in other patient populations. We therefore hypothesize that it is safe to continue trastuzumab in patients with asymptomatic or mildly symptomatic fall in LVEF, when concomitantly treated with ACE-I and beta blockers.

Methods: In this retrospective chart review, we identified 18 consecutive patients with stage 1-3 HER-2 positive breast cancer patients who had a decline in LVEF meeting the criteria above to withhold trastuzumab, and who were referred to our cardio-oncology service from the beginning of 2015 to March 2017. These patients were offered and consented to receive ongoing trastuzumab accompanied by ACE-I and/or beta blocker. Data on patient demographics, cancer therapies, clinical features, LVEF, and cardiac medications were extracted from medical charts.

Results: Among the 18 patients identified, all were women, 12 (67%) were estrogen receptor positive, and 7 progesterone receptor positive (39%). 11 (61%) of patients had a left-sided breast cancer, 6 (33%) had right-sided breast cancer, and 1 (5%) had an unspecified side breast cancer. 17 (94%) of patients had previously undergone radiation therapy, and 4 (22%) had experienced a recurrence. 16 patients had received a prior anthracycline regimen (10 sequentially, 6 concurrently). The patients were treated with one or a combination of the following medications: carvedilol (n=13), ramipril (n=12), bisoprolol (n=1), candesartan (n=2), rosuvastatin (n=2), atorvastatin (n=2). The patients were followed up for an average of 7 months after starting cardiac therapy. Table 1 summarizes the mean±SD LVEF values over the follow up time period. All patient except one (94%) completed trastuzumab treatment successfully. This patient with concomitant moderate-severe mitral regurgitation was hospitalized for pulmonary edema. Trastuzumab was discontinued and LVEF has subsequently returned to normal values.

Table 1: LVEF progression from baseline to end of follow-upMean±SD LVEF at baseline57.59±5.49%Mean±SD LVEF on referral to cardio-oncology clinic50.75±4.76%Mean±SD LVEF at end of follow-up56.35±3.50%

Conclusion: Treating cardiac dysfunction related to trastuzumab in a cardio-oncology clinic, using beta blockers and ACE-I may enable completion of trastuzumab therapy. Randomized trials are necessary before it can be widely recommended, however findings from our experience suggest this may be a promising new treatment strategy.

Citation Format: Bharaj UK, Leong D, Dhesy-Thind S, Ellis P, Mukherjee S, Bordeleau L, Phillips C, Brown M, Kumar Tyagi N. Safety of continuing chemotherapy in overt left ventricular dysfunction using antibodies to human epidermal growth factor receptor-2: A retrospective study [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 P5-20-17.

Abstract PD2-13: Benefits to breast screening beyond mortality reduction

Background

The value of population-based mammographic screening has been questioned by those who believe that the reduction in mortality from earlier diagnosis is outweighed by harms including overdiagnosis and overtreatment. Much of these commentaries assume that all Early-Stage Breast Cancer (ESBC) is treated the same way after diagnosis; with extensive therapies including surgery, radiotherapy and chemotherapy being standard.

Intensity of treatment received is rarely mentioned in the debate. We hypothesised that those diagnosed through a screening program (Active Screeners (AS)) would receive less extensive surgical treatment and less intense adjuvant therapies than those not recently screened (NRS). If demonstrated, these differences would form an important component of the debate over the role of mammographic screening.

Methods

Retrospective analysis of a consecutive cohort of female patients aged 50-69 and managed for ESBC (invasive or DCIS) during 2007-2013 within a large metropolitan Breast Service, diagnosed either via a population screening program (AS) or outside of the program (NRS). Data on patient characteristics, symptoms, mode of detection, tumour pathology, surgical intervention and adjuvant treatment recommendations were derived from prospectively collected Multi-Disciplinary Meeting (MDM) records. Patients with metastatic disease or prior treatment for breast cancer were excluded.

Results

791 cases were identified (569 with screen-detected cancer, 53 with interval cancers and 169 cancers diagnosed in women not recently screened). Invasive cancers in the AS group were much smaller than in the NRS group – mean 17mm versus 26mm. The AS group had lower grade invasive cancer – grade 1, 2 and 3 were 27%, 42%, 31% - compared with 10%, 39% and 52% in the NRS group. The AS group were more likely to have ER+ve cancers (88% vs 80%) and less likely to have nodal involvement (26% vs 48%). For invasive breast cancer, the NRS group were more than twice as likely to undergo mastectomy than cancers in the AS group (35% vs 16%). Axillary dissections were more common in the NRS than the AS group (43% vs 19%). Adjuvant chemotherapy was recommended more frequently for the NRS group compared to the AS group (65% vs 37%), as was post mastectomy radiotherapy (58% vs 39%). Endocrine therapy was less often recommended to the NRS group (86% versus 77%).

Conclusion

Women diagnosed with early stage breast cancer who are participating in a population based screening program are less likely to receive mastectomy and/or axillary dissection, less likely to receive adjuvant chemotherapy and less likely to receive post-mastectomy radiotherapy. These differences in treatment intensity should be considered in the debate surrounding mammographic screening.

Citation Format: Elder KJ, Nickson C, Cooke S, Machalek D, Rose A, Mou A, Collins JP, Park A, De Boer R, Phillips C, Pridmore V, Farrugia H, Mann GB. Benefits to breast screening beyond mortality reduction [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 PD2-13.

Oral Sciences PhD Program Enrollment, Graduates, and Placement: 1994 to 2016

For decades, dental schools in the United States have endured a significant faculty shortage. Studies have determined that the top 2 sources of dental faculty are advanced education programs and private practice. Those who have completed both DDS and PhD training are considered prime candidates for dental faculty positions. However, there is no national database to track those trainees and no evidence to indicate that they entered academia upon graduation. The objective of this study was to assess outcomes of dental school-affiliated oral sciences PhD program enrollment, graduates, and placement between 1994 and 2016. Using the American Dental Association annual survey of advanced dental education programs not accredited by the Commission on Dental Accreditation and data obtained from 22 oral sciences PhD programs, we assessed student demographics, enrollment, graduation, and placement. Based on the data provided by program directors, the average new enrollment was 33, and graduation was 26 per year. A total of 605 graduated; 39 did not complete; and 168 were still in training. Among those 605 graduates, 211 were faculty in U.S. academic institutions, and 77 were faculty in foreign institutions. Given that vacant budgeted full-time faculty positions averaged 257 per year during this period, graduates from those oral sciences PhD programs who entered academia in the United States would have filled 9 (3.6%) vacant faculty positions per year. Therefore, PhD programs have consistently generated only a small pipeline of dental school faculty. Better mentoring to retain talent in academia is necessary. Stronger support and creative funding plans are essential to sustain the PhD program. Furthermore, the oral sciences PhD program database should be established and maintained by dental professional organizations to allow assessments of training models, trends of enrollment, graduation, and placement outcomes.

Embedding Anatomical or Functional Knowledge in Whole-Brain Multiple Kernel Learning Models

Pattern recognition models have been increasingly applied to neuroimaging data over the last two decades. These applications have ranged from cognitive neuroscience to clinical problems. A common limitation of these approaches is that they do not incorporate previous knowledge about the brain structure and function into the models. Previous knowledge can be embedded into pattern recognition models by imposing a grouping structure based on anatomically or functionally defined brain regions. In this work, we present a novel approach that uses group sparsity to model the whole brain multivariate pattern as a combination of regional patterns. More specifically, we use a sparse version of Multiple Kernel Learning (MKL) to simultaneously learn the contribution of each brain region, previously defined by an atlas, to the decision function. Our application of MKL provides two beneficial features: (1) it can lead to improved overall generalisation performance when the grouping structure imposed by the atlas is consistent with the data; (2) it can identify a subset of relevant brain regions for the predictive model. In order to investigate the effect of the grouping in the proposed MKL approach we compared the results of three different atlases using three different datasets. The method has been implemented in the new version of the open-source Pattern Recognition for Neuroimaging Toolbox (PRoNTo).