Advanced cutaneous squamous cell carcinoma: Impact of age on the safety and efficacy of cemiplimab and the prognostic significance of blood biomarkers

INTRODUCTION

Age-related differences in the safety profile of cemiplimab for patients with locally advanced or metastatic cutaneous squamous cell carcinoma (cSCC) have not been well described. We investigated the association of increasing age with immune related adverse events (irAE) from cemiplimab, efficacy outcomes, and the prognostic significance of pre-treatment blood biomarkers in contemporary practice.

MATERIALS AND METHODS

Patients starting first-line cemiplimab for locally advanced or metastatic cSCC at British Columbia Cancer between April 2019 and January 2023 were identified. Landmark four-month logistic regression analysis compared the odds of developing irAE or sequelae amongst patients aged <75 years to those aged 75-84 or ≥ 85. Objective responses were determined using Response Evaluation Criteria in Solid Tumors version 1.1. Univariable Cox proportional hazard (PH) regression modelling of factors associated with overall survival (OS) was performed.

RESULTS

Of 106 patients, the proportions aged <75, 75-84, and ≥ 85 years were 34%, 45%, and 21%, respectively. Overall, the proportion of patients with irAE ≥ grade 3, cemiplimab discontinuation, and hospitalization for immune toxicity was 27.4%, 31.1%, and 11.3%, respectively. There was no clear association between age and the odds of high grade irAE. However, increased odds of cemiplimab discontinuation was observed in patients aged 75-84 years (p = 0.05). Patients ≥85 years had increased hospitalizations due to irAE (OR = 5.00, 95% CI = 0.97-37.52) with two treatment-related deaths. Objective responses were similar across age cohorts (50.0%, 60.4%, and 54.5%) but progressive disease was higher in the age ≥ 85 group (22.2%, 18.8%, and 31.8%). On Cox PH regression analysis, age ≥ 85 years (vs. <75), Eastern Cooperative Oncology Group performance status 2-3 (vs. 0-1), and neutrophil to lymphocyte ratio (NLR) ≥7.80 (vs. <7.80) were associated with shorter survival.

DISCUSSION

While the odds of high grade irAE were similar across age groups, significant age-related differences in treatment discontinuation and hospitalization due to immune toxicity were observed. Despite a higher incidence of primary progression and shorter OS in the oldest cohort, cemiplimab yielded robust objective responses regardless of age. Higher pre-treatment NLR was associated with shorter survival and the cut-point identified requires further study.

Temporal and spatial variation of domoic acid along Canada's coast

Shellfish poisonings have posed severe risks to human health globally. The Canadian Shellfish Sanitation Program was established in 1948 to monitor the toxin levels at shellfish harvesting sites along the coast of six provinces in Canada. Domoic acid has been a causal toxin for amnesic shellfish poisoning, and a macro-scale analysis of the temporal and spatial variation of domoic acid along Canada's coast were conducted in this study. We aggregated the toxin levels by week in blue mussel (Mytilus edulis) and soft-shell clam (Mya arenaria) samples, respectively, over a one-year scale. The subsequent application of Functional Principal Component Analysis unveiled that magnitudes of seasonal variation and peaked DA levels around early summer, spring, or mid-fall formed the largest variation in the toxin levels in blue mussels along coastlines of British Columbia and Prince Edward Island and in soft-shell calms along those of New Brunswick and Nova Scotia. In Quebec, the DA levels were low and varied mostly in terms of the overall magnitude across spring to fall. Downstream correlation analyses in British Columbia further discovered that, at most sites, the strongest correlations were negative between precipitation as well as inorganic nutrients (including nitrate, nitrite, phosphate, and silicate) on one side and DA a few weeks afterward on the other. These findings indicated associations between amnesic shellfish poisoning and environmental stresses.

Longitudinal Study of Paralytic Shellfish Toxins along Canada's Coast

Paralytic shellfish toxins (PST) in shellfish products have led to severe risks to human health. To monitor the risk, the Canadian Shellfish Sanitation Program has been collecting longitudinal PST measurements in blue mussel (Mytilus edulis) and soft-shell clam (Mya arenaria) samples in six coastal provinces of Canada. The spatial distributions of major temporal variation patterns were studied via Functional Principal Component Analysis. Seasonal increases in PST contamination were found to vary the most in terms of magnitude along the coastlines, which provides support for location-specific management of the time-sensitive PST contamination. In British Columbia, the first functional principal component (FPC1) indicated the variance among the magnitudes, while FPC2 indicated the seasonality of the PST levels, which tended to be positively correlated with the abundance of dianoflagellates Alexandrium spp., and negatively with precipitation and inorganic nutrients. These findings indicate the underlying mechanism of PST variation in various geographical settings. In New Brunswick, Prince Edward, and Nova Scotia, the top FPCs indicated that the PST contamination differed mostly in the seasonal increase of the PST level during summer.

First-line osimertinib for patients with EGFR-mutated advanced non-small cell lung cancer: efficacy and safety during the COVID-19 pandemic

Background

The FLAURA trial demonstrated improved overall survival (OS) with first-line osimertinib for patients with epidermal growth factor receptor (EGFR)-mutated advanced non-small cell lung cancer (NSCLC). We studied the efficacy and safety of osimertinib in a cohort treated during the coronavirus disease 2019 (COVID-19) pandemic.

Methods

Patients diagnosed with EGFR-mutated advanced NSCLC between 11 March 2020 to 31 December 2021 who received first-line osimertinib in British Columbia, Canada were identified retrospectively. Kaplan-Meier curves of OS and progression-free survival (PFS) from the start of osimertinib were plotted. The associations of baseline characteristics with PFS, and development of pneumonitis or dose reductions due to toxicity with OS were evaluated with hazard ratios estimated using univariable and multivariable Cox models.

Results

The cohort comprised 231 individuals. 58.7% of patients with de novo advanced NSCLC were initially diagnosed after presentation to the Emergency Room. At osimertinib initiation, 31.6% were aged ≥75 years and 45.5% had an Eastern Cooperative Oncology Group performance status (ECOG PS) ≥2. Median PFS and OS were 18.0 months [95% confidence interval (CI): 16.1-26.2] and 25.4 months (95% CI: 20.3-not reached), respectively. On multivariable analysis, age ≥75 years (vs. <75), ECOG PS 2/3 (vs. 0/1), ECOG PS 4 (vs. 0/1), current smokers (vs. never smokers), programmed death ligand 1 (PD-L1) expression ≥50% (vs. <1%), and L858R mutation (vs. exon 19 deletion) were associated with shorter PFS. Among 110 patients who progressed, 33.6% received subsequent therapy. A proportion of 16.5% of the cohort developed grade ≥3 adverse events. Pneumonitis from osimertinib (3.9% incidence) was weakly associated with shorter OS (hazard ratio: 2.59, 95% CI: 0.94-7.12, P=0.066); dose reductions were not associated with worse OS. 10.8% of patients developed COVID-19.

Conclusions

In a cohort receiving first-line osimertinib during the COVID-19 pandemic, ECOG PS ≥2 was observed in nearly half of patients at treatment initiation contributing to a median OS shorter than in FLAURA. The incidence of severe adverse events was low and dose reduction for drug toxicity did not impact OS. Identifying and reducing barriers to the diagnosis of NSCLC during the COVID-19 pandemic are required.

CD8 + T cell infiltration is associated with improved survival and negatively correlates with hypoxia in clear cell ovarian cancer

Unlike other histological types of epithelial ovarian carcinoma, clear cell ovarian carcinoma (CCOC) has poor response to therapy. In many other carcinomas, expression of the hypoxia-related enzyme Carbonic anhydrase IX (CAIX) by cancer cells is associated with poor prognosis, while the presence of CD8 + tumor-infiltrating lymphocytes (TIL) is positively prognostic. We employed [¹⁸F]EF5-PET/CT imaging, transcriptome profiling, and spatially-resolved histological analysis to evaluate relationships between CAIX, CD8, and survival in CCOC. Tissue microarrays (TMAs) were evaluated for 218 cases in the Canadian COEUR study. Non-spatial relationships between CAIX and CD8 were investigated using Spearman rank correlation, negative binomial regression and gene set enrichment analysis. Spatial relationships at the cell level were investigated using the cross K-function. Survival analysis was used to assess the relationship of CAIX and CD8 with patient survival for 154 cases. CD8 + T cell infiltration positively predicted survival with estimated hazard ratio 0.974 (95% CI 0.950, 1000). The negative binomial regression analysis found a strong TMA effect (p-value < 0.0001). It also indicated a negative association between CD8 and CAIX overall (p-value = 0.0171) and in stroma (p-value = 0.0050) but not in tumor (p-value = 0.173). Examination of the spatial association between the locations of CD8 + T cells and CAIX cells found a significant amount of heterogeneity in the first TMA, while in the second TMA there was a clear signal indicating negative spatial association in stromal regions. These results suggest that hypoxia may contribute to immune exclusion, primarily mediated by effects in stroma.

Dynamics of fecal coliform bacteria along Canada's coast

The vast coastline provides Canada with a flourishing seafood industry including bivalve shellfish production. To sustain a healthy bivalve molluscan shellfish production, the Canadian Shellfish Sanitation Program was established to monitor the health of shellfish harvesting habitats, and fecal coliform bacteria data have been collected at nearly 15,000 marine sample sites across six coastal provinces in Canada since 1979. We applied Functional Principal Component Analysis and subsequent correlation analyses to find annual variation patterns of bacteria levels at sites in each province. The overall magnitude and the seasonality of fecal contamination were modelled by functional principal component one and two, respectively. The amplitude was related to human and warm-blooded animal activities; the seasonality was strongly correlated with river discharge driven by precipitation and snow melt in British Columbia, but such correlation in provinces along the Atlantic coast could not be properly evaluated due to lack of data during winter.

Time to Treatment With Nivolumab or Pembrolizumab for Patients With Advanced Melanoma in Everyday Practice

Background The anti-programmed cell death one antibodies (Anti-PD-1 Ab) pembrolizumab or nivolumab are commonly prescribed to patients with advanced melanoma. The purpose of the current study is to identify baseline clinical characteristics associated with time to treatment initiation (TTI) of pembrolizumab or nivolumab for advanced melanoma and whether treatment delays are associated with differences in survival outcomes. Methods All patients receiving Anti-PD-1 Ab as a first-line treatment for advanced melanoma outside of clinical trials at British Columbia Cancer Agency between 10/2015 and 10/2019 were identified retrospectively. TTI was defined as the interval from pathologic diagnosis of advanced melanoma to first Anti-PD-1 Ab treatment. To determine the association between TTI and baseline characteristics, multivariable Cox proportional hazard regression analyses provided an estimate of the instantaneous relative risk of starting treatment at any time point (hazard ratio [HR] >1 indicates shorter TTI). To describe changes in overall survival (OS) observed for each four-week delay in treatment initiation, multivariable cox proportional hazard regression modelling was also performed. Results In a cohort of 302 patients, the median TTI was 52 days (interquartile range 30.2-99.0). Pulmonary metastases (M1b)/non-central nervous system visceral metastases (M1c) vs. metastases to skin or non-regional lymph nodes (M1a)(HR=1.50, 95% CI=1.12-2.02; p=0.007) and pre-treatment Eastern Cooperative Oncology Group Performance Status (ECOG PS) >1 (vs 0/1, HR=1.50, 95% CI= 1.11-2.01; p=0.008) were associated with earlier TTI. An association between treatment delay and improved OS was observed. Conclusion Patients having visceral metastases and poor baseline ECOG PS were more likely to initiate Anti-PD-1 Ab sooner. The association of shorter TTI with worse OS likely represents confounding by indication (urgent treatment offered to patients with aggressive disease).

Immune related adverse events and treatment discontinuation in patients older and younger than 75 years with advanced melanoma receiving nivolumab or pembrolizumab

BACKGROUND

Programmed cell-death 1 antibodies (PD-1 Ab) improve overall survival (OS) for patients with advanced melanoma in trials; however, safety data in patients ≥75 years are lacking. The prognostic significance of and risk factors for PD-1 Ab discontinuation due immune related adverse events (irAE) are also uncertain.

METHODS

Patients with advanced melanoma receiving frontline PD-1 Ab at British Columbia Cancer outside of clinical trials between 10/2015-10/2019 were retrospectively analyzed. The incidence and subtypes of irAE were compared between age subgroups <75 and ≥ 75 years. Univariable logistic regression identified variables associated with treatment discontinuation within four months of PD-1 Ab initiation. Cox proportional hazard regression models were used to determine factors significantly associated with OS.

RESULTS

302 patients were identified, of whom 126 (41.7%) were ≥ 75 years. During all follow-up, 15.9% of patients experienced irAE grade 3/4 and 27.2% of the cohort stopped PD-1 Ab due to immune toxicity. irAE incidence, hospitalization, and need for steroids by the four-month landmark were similar amongst age groups. Advanced age was not associated with risk of PD-1 Ab discontinuation from irAE on logistic regression. For the entire cohort, pre-treatment factors associated with shorter OS on multivariable analysis were ECOG performance status ≥1, M1d stage, lactate dehydrogenase >224, and neutrophil/ lymphocyte ratio ≥ 5. On four-month landmark multivariable analysis, treatment discontinuation due to irAE was significantly associated with worse OS.

CONCLUSION

Patients aged ≥75 years experienced similar irAE rates and treatment discontinuation for immune toxicity compared to younger patients. As PD-1 Ab discontinuation due to irAE was associated with shorter OS, efforts to treat irAE early are warranted to potentially avoid therapy cessation.

Survival Outcomes Following Discontinuation of Ipilimumab and Nivolumab for Advanced Melanoma in a Population-based Cohort

AIMS

Induction ipilimumab and nivolumab followed by maintenance nivolumab improve overall survival compared with ipilimumab alone in patients with advanced melanoma, but immune-related adverse events (irAE) occur commonly. The need for induction discontinuation because of irAE and the relationship between irAE and survival in non-trials patients are unclear.

MATERIALS AND METHODS

Patients with unresectable stage III-IV melanoma receiving first-line combination immunotherapy at one of six centres between December 2017 and February 2020 outside of trials were identified retrospectively. Landmark 12-week Kaplan-Meier analyses and log-rank tests were used to evaluate associations between discontinuation of induction therapy on overall survival and time to treatment failure (TTF). Multivariable analysis of factors influencing overall survival and TTF was undertaken.

RESULTS

Among 95 patients, the median age was 62 years, 38.9% had Eastern Cooperative Oncology Group performance status ≥1 and 22.1% had brain metastases. The median follow-up for the whole cohort was 19.8 months by the reverse Kaplan-Meier method. Any grade and grade 3-4 irAE were noted in 78.9% and 44.2% of the cohort, respectively. 44.2% of patients completed induction immunotherapy, whereas 41.1% did not due to irAE. Twelve-week landmark overall survival and TTF were similar in patients who completed induction versus those who did not due to irAE. On multivariable analysis, any grade irAE (versus none) was associated with longer overall survival (hazard ratio = 0.35, 95% confidence interval 0.15-0.82, P = 0.02) and TTF (hazard ratio = 0.38, 95% confidence interval = 0.17-0.81, P = 0.01). Grade 3-4 irAE correlated with longer TTF (hazard ratio = 0.45, 95% confidence interval = 0.20-1.01, P = 0.05).

CONCLUSION

In this population-based cohort, discontinuation of induction immunotherapy as a result of irAE did not adversely affect overall survival or TTF. irAE observed during ipilimumab and nivolumab induction were associated with improved survival outcomes.

Comparisons of simulation results between passive and active fluid structure interaction models for left ventricle in hypertrophic obstructive cardiomyopathy

BACKGROUND

Patient-specific active fluid-structure interactions (FSI) model is a useful approach to non-invasively investigate the hemodynamics in the heart. However, it takes a lot of effort to obtain the proper external force boundary conditions for active models, which heavily restrained the time-sensitive clinical applications of active computational models.

METHODS

The simulation results of 12 passive FSI models based on 6 patients' pre-operative and post-operative CT images were compared with corresponding active models to investigate the differences in hemodynamics and cardiac mechanics between these models.

RESULTS

In comparing the passive and active models, it was found that there was no significant difference in pressure difference and shear stress on mitral valve leaflet (MVL) at the pre-SAM time point, but a significant difference was found in wall stress on the inner boundary of left ventricle (endocardium). It was also found that pressure difference on the coapted MVL and the shear stress on MVL were significantly decreased after successful surgery in both active and passive models.

CONCLUSION

Our results suggested that the passive models may provide good approximated hemodynamic results at 5% RR interval, which is crucial for analyzing the initiation of systolic anterior motion (SAM). Comparing to active models, the passive models decrease the complexity of the modeling construction and the difficulty of convergence significantly. These findings suggest that, with proper boundary conditions and sufficient clinical data, the passive computational model may be a good substitution model for the active model to perform hemodynamic analysis of the initiation of SAM.

Prognostic significance of the neutrophil-to-lymphocyte ratio and platelet-to-lymphocyte ratio for advanced non-small cell lung cancer patients with high PD-L1 tumor expression receiving pembrolizumab

Background

We investigated the association of peripheral blood inflammatory markers with overall survival (OS) in pembrolizumab treated advanced non-small cell lung cancer (aNSCLC) patients with programmed death ligand 1 (PD-L1) expression ≥50%. Clinical risk factors for development of immune-related adverse events (irAE) were also explored.

Methods

aNSCLC patients with high PD-L1 expression receiving pembrolizumab monotherapy outside of clinical trials were identified retrospectively. All patients were treated at one of six British Columbia Cancer clinics between August 2017 and June 2019. Patients were dichotomized using baseline neutrophil-to-lymphocyte ratio (NLR, </≥6.4) and platelet-to-lymphocyte ratio (PLR, </≥441.8). Factors associated with OS were assessed with Cox proportional hazard models. Logistic regression models were utilized in landmark analysis of risk factors for irAE.

Results

Among 220 patients, median age was 70.0 years, 55.0% were female, 40.5% had baseline Eastern Cooperative Oncology Group performance status (ECOG PS) 2/3, and 95.5% received frontline pembrolizumab. Median OS for the cohort was 11.8 months (95% CI: 8.7–15.4). On multivariable analysis, baseline NLR ≥6.4 [hazard ratio (HR): 2.31, 95% confidence interval (CI): 1.46–3.64, P<0.001], baseline PLR ≥441.8 (HR: 2.03, 95% CI 1.22–3.37, P=0.006), and pre-treatment ECOG PS 2/3 (HR: 2.19, 95% CI: 1.48–3.26, P<0.001) were associated with worse OS. The incidence of any grade irAE and irAE grade ≥3 were 40.5% and 12.3%, respectively. ECOG PS 2/3 (vs. 0/1) patients were at 3.76-fold higher risk of developing an irAE by the 8-month landmark (P=0.002).

Conclusions

High NLR and PLR were associated with shorter OS in a cohort of patients receiving largely frontline pembrolizumab for aNSCLC in routine practice. ECOG PS 2/3 was associated with higher risk of developing an irAE. Given that NLR and PLR values are easily obtainable, prospective studies are warranted to confirm their prognostic significance in this patient population and explore a predictive utility.

Treatment of non-small-cell lung cancer after progression on nivolumab or pembrolizumab

Background

Although PD-1 antibodies (PD1 Ab) are the standard of care for advanced non-small-cell lung cancer (ansclc), most patients will progress. We compared survival outcomes for patients with ansclc who received systemic therapy (st) after progression and for those who did not. Additionally, clinical characteristics that predicted receipt of st after PD1 Ab failure were evaluated.

Methods

All patients with ansclc in British Columbia initiated on nivolumab or pembrolizumab between June 2015 and November 2017, with subsequent progression, were identified. Eligibility criteria for additional st included an Eastern Cooperative Oncology Group (ecog) performance status (ps) of 3 or less and survival for more than 30 days from the last PD1 Ab treatment. Post-progression survival (pps) was assessed by landmark analysis. Baseline characteristics associated with pps were identified by multivariable analysis.

Results

Of 94 patients meeting the eligibility criteria, 33 received st after progression. In 75.6%, a PD1 Ab was received as first- or second-line treatment. The most common sts were erlotinib (36.4%) and docetaxel (27.3%). No statistically significant difference in median pps was observed between patients who did and did not receive st within 30 days of their last PD1 Ab treatment (6.9 months vs. 3.6 months, log-rank p = 0.15.) In multivariable analysis, factors associated with increased pps included an ecog ps of 0 or 1 compared with 2 or 3 [hazard ratio (hr): 0.42; 95% confidence interval (ci): 0.24 to 0.73; p = 0.002] and any response compared with no response to PD1 Ab (hr: 0.54; 95% ci: 0.33 to 0.90; p = 0.02).

Conclusions

In this cohort, only 35.1% of patients eligible for post-PD1 Ab therapy received st. Post-progression survival was not significantly affected by receipt of post-progression therapy. Prospective trials are needed to clarify the benefit of post-PD1 Ab treatments.

Pembrolizumab (Pem) for advanced non-small cell lung cancer (aNSCLC): Efficacy and safety in everyday clinical practice

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Background: In clinical trials, Pem improves overall survival (OS) compared to chemotherapy in a subset of patients (pts) with aNSCLC. Immune related adverse events (irAE) have correlated with improved OS in some studies. We explored efficacy and safety of Pem in a provincial population. Methods: aNSCLC pts treated with Pem between 06/2015 and 08/2018 at BC Cancer were retrospectively identified. Kaplan-Meier curves of OS from initiation of Pem were plotted and multivariable analysis (MVA) was performed with Cox proportional hazard regression models. 3, 6, and 9 month landmark Kaplan-Meier analysis was performed and log-rank tests used to determine the association of irAE subtypes with OS. Multivariable logistic regression models for irAE within 3 months of Pem initiation were also fit. Results: Characteristics of the 190 pt cohort: median age 70y (41-91), ECOG PS 2/3 at start of Pem: 34.2%, squamous histology: 22.1%, EGFR mutation: 3.7%, brain (13.7%) or liver (8.9%) metastases, PD-L1 expression ≥ 50%: 92.6%, treatment line: 1st/ ≥2nd: 74.2%/25.8%. Median cycles delivered 7 (range 1-35). With median survival follow-up of 6.1 months (range 0.03-39.8 months) and 43% pts decreased, median OS of Pem in the 1st line and ≥2nd line settings were 24.3 months (95% CI, 9.7-not reached, NR) and 13.4 months (95% CI, 8.1-NR), respectively. Pts with ECOG PS 2/3 had lower OS vs. ECOG PS 0/1 (5.8 months vs. 16.7 months, log-rank p < 0.0001). On MVA, only ECOG PS (p < 0.001) was associated with OS. 66 pts (34.7% of cohort) experienced 89 irAE; most common irAE: dermatitis (20pts), hypothyroidism (13pts), and pneumonitis (10pts). 8.4% of cohort developed grade 3 or 4 irAE; no grade 5 irAE. The odds of a grade ≥ 3 irAE within 3 months was 6.3 fold higher if ECOG 2/3 vs. 0/1 (p = 0.05). A weak association between pneumonitis and decreased OS at 9 month landmark (p = 0.09) was seen; otherwise no association with irAE subtypes at 3, 6, and 9 month landmarks was observed. Conclusions: In the whole cohort, clinical efficacy and toxicity of Pem was consistent with registration trials. Pts with ECOG PS 2/3 had a significantly lower OS and higher odds of developing grade ≥ 3 irAE than those with good ECOG PS 0/1.

Pembrolizumab for advanced nonsmall cell lung cancer: Efficacy and safety in everyday clinical practice

OBJECTIVES

While pembrolizumab improves overall survival (OS) in a subset of advanced nonsmall cell lung cancer (aNSCLC) patients (pts) in clinical trials, individuals with poor Eastern Cooperative Oncology Group performance status (ECOG PS) were excluded. Furthermore, some studies have identified a potential link between improved pt outcomes and development of immune related adverse events (irAE.) In a large provincial cohort, we studied the efficacy and safety of pembrolizumab for poor ECOG PS pts and whether irAE correlate with improved OS.

MATERIALS AND METHODS

aNSCLC pts treated with pembrolizumab between 06/2015 and 08/2018 at BC Cancer were retrospectively identified. Kaplan-Meier curves of OS from initiation of pembrolizumab were plotted. 3-, 6-, and 9- month landmark Kaplan-Meier analysis was performed and log-rank tests used to determine an association of irAE subtypes with OS. Multivariable logistic regression identified variables associated with grade ≥3 irAE within 3 months of pembrolizumab initiation.

RESULTS

Of 190 pts, 74.2% were treatment naïve and 92.6% had PD-L1 expression ≥ 50%. Median OS in the 1st line and ≥2nd line settings were 24.3 months (95% CI, 9.7-not reached, NR) and 13.4 months (95% CI, 8.1-NR), respectively. Pts with ECOG PS 2/3 had lower median OS than if ECOG PS 0/1 (5.8 months vs. 16.7 months, p < 0.0001). In multivariable analysis, the odds of grade ≥ 3 irAE within 3 months was 6.3 fold higher if ECOG PS 2/3 versus 0/1 (p = 0.05). Development of pneumonitis at the 9 month landmark weakly correlated with decreased OS (p = 0.09).

CONCLUSION

In the studied cohort, ECOG PS 2/3 pts had a significantly lower OS and greater odds of experiencing high-grade irAE than if ECOG PS 0/1. Development of irAE did not result in improved OS. Randomized trials to determine benefit of pembrolizumab for poor ECOG PS pts are needed.

Toward A Population-Based Approach to End-Of-Life Care Surveillance in Canada: Initial Efforts and Lessons

This paper describes a project undertaken by the Hospice Palliative End-of-Life Care Surveillance Team Network — one of four Cancer Surveillance and Epidemiology Networks established by the Canadian Partnership Against Cancer in 2009 to create information products that can be used to inform cancer control. The project was designed to improve the quality and use of existing electronic patient databases in its member organizations. The project's intent was to better understand terminally ill cancer patients in their final year of life, with noncancer as comparison. The network created an early design for a Web-based end-of-life care surveillance system prototype. Using a flagging process, anonymized data sets on cancer/ noncancer palliative patients and those who died in 2008–2009 were extracted and analyzed. The Australian palliative approach was adapted as the conceptual model based on the data sets available. Common data elements were defined then mapped to local data sets to create a common data set. Information products were created as online reports. Throughout the project, members were engaged in knowledge translation. Overall, the project was well received by network members. There are still major data-quality and linkage issues that require further work.

Conversion of Karnofsky Performance Status (Kps) and Eastern Cooperative Oncology Group Performance Status (Ecog) to Palliative Performance Scale (Pps), and the interchangeability of Pps and Kps in Prognostic Tools

Aim: The aim of our study was to assess whether the Karnofsky Performance Status (KPS), the Eastern Cooperative Oncology Group (ECOG) Performance Status, and the Palliative Performance Scale (PPS) are interchangeable individually or within two prognostic tools: the Palliative Prognostic Score (PaP) and the Palliative Prognostic Index (PPI). Methods: We performed a subset analysis of a prospective comparative study of functional and prognostic tools and clinician prediction of survival. We studied 955 patients with advanced life-limiting illnesses (cancer and non-cancer) in the acute care and community settings. We used a descriptive statistical model and Spearman's rank correlation to assess these interchangeabilities. Results: There is a direct positive linear relationship between the KPS and the PPS, and a direct negative linear relationship between these tools and the ECOG. Exchange of the KPS and the PPS was possible within the PaP and the PPI. Conclusion: The PPS and the KPS can be used interchangeably as functional tools and within prognostic tools. The ECOG is interchangeable with the PPS and the KPS, but this interchange-ability is population-specific.

Subventricular Zone Radiation Dose and Outcome for Glioblastoma Treated Between 2006 and 2012

Objective Stem cells residing in the subventricular zone (SVZ) may be related to recurrence, potentially affecting outcome in glioblastoma (GBM). This study investigated the relationship of SVZ radiation dose and survival in a large cohort treated with surgery and chemoradiotherapy (CRT). Methods Patients with GBM treated between 2006 and 2012 (n = 370) were identified. SVZs were contoured from planning computed tomography (CT) with magnetic resonance imaging (MRI) registration where available. Dose was extracted from dose volume histograms. Kaplan-Meier (KM) progression-free survival (PFS) and overall survival (OS) estimates were compared with log-rank tests for SVZ doses. Multivariate analysis (MVA) identified clinical and treatment-related factors significantly associated with outcome. Results Median follow-up was 16.4 months, 48.1% underwent gross total resection (GTR), 37.5% subtotal resection, and 14.4% biopsy without resection. Median PFS was 8.9 months (95% CI: 8.3-9.8 months), and OS was 16.5 months (95% CI: 15.2-17.6 months). PFS was significantly lower for older age (>50 years, P = 0.045), poor Karnofsky performance status (KPS, P = 0.049), multifocality (P < 0.001), and incomplete adjuvant chemotherapy (P < 0.001). Worse OS was associated with poor KPS (P = 0.001), biopsy only (P = 0.003), multifocality (P = 0.009), and failure to complete adjuvant chemotherapy (P < 0.001). SVZ dose was not associated with outcome for any of the dose levels assessed. On MVA, multifocality was associated with worse PFS (P < 0.01). Poor performance status and biopsy only were associated with worse OS (both P < 0.01). Conclusion In this analysis of a large cohort of GBM treated with surgery and CRT, increased SVZ dose was not associated with improved survival.

Safety and clinical efficacy of programmed cell death 1 antibodies (PD-1 Ab) in patients with advanced non-small cell lung cancer (NSCLC)

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Background: In advanced NSCLC, clinical trials have shown significant benefits to pembrolizumab (P) and nivolumab (N). At BC Cancer, clinicians utilize protocol based algorithms to manage immune related adverse events (irAE). The incidence of irAE and efficacy of PD-1 Ab in everyday practice might differ from clinical trials. Methods: Advanced NSCLC patients (pts) treated with N or P between 11/2015 to 10/2017 at BC Cancer were identified. Demographic, tumor, treatment details, and frequency and grade (Gr, CTCAE v4.0) of irAE, were abstracted. Kaplan-Meier curves of median overall survival (OS) from initiation of PD-1 Ab were generated. Multivariable analysis (MVA) with 6-week landmark analysis was performed with Cox proportional hazard regression models. Results: Characteristics of cohort (230 N- and 41 P- treated): median age 64y (range 39-82), non-squamous histology 75%, ECOG PS > 1 at start of PD-1 Ab 31%, brain metastases (mets) 13%, liver mets 12%, and median Charlson Comorbidity Index (CCI) score 6. One hundred sixteen pts experienced 169 separate irAE: Gr1(74), Gr2 (68), Gr3(13), Gr4(10), Gr 5(4). Pneumonitis (14.6% vs. 4.8%, p = 0.041) and arthralgias (12.2% vs. 3.5%, p = 0.044) were more common in P than N. Steroids were administered to 25.2% of N pts and 19.5% of P pts (p = 0.557). Median follow-up from initiation of PD-1 Ab was 8.1months (range 0.1-33.9); median OS (95% CI) for N was 9.2 months (7.75-12.4) and for P was 13.5 months (10.6-not reached). 6-week landmark MVA for whole cohort revealed that male sex (p = 0.051), CCI≥3 (p < 0.001), ECOG PS > 1 (p < 0.001), liver mets (p = 0.017) and development of irAE > Gr2 versus no irAE (p = 0.036) were associated with decreased OS. Age, smoking status, histology, brain mets, EGFR status, irAE Gr 1/2 versus no irAE, and type of PD-1 Ab were not significant. Conclusions: Severe irAE were rare; pneumonitis and arthralgias were more common in P- than N- treated patients. The association with CCI, ECOG PS, and liver mets with decreased OS are consistent with literature. Association of severe irAE with shorter OS might reflect the need for improved physician education in irAE treatment algorithms.

Transcriptomics investigation of thyroid hormone disruption in the olfactory system of the Rana [Lithobates] catesbeiana tadpole

Thyroid hormones (THs) regulate vertebrate growth, development, and metabolism. Despite their importance, there is a need for effective detection of TH-disruption by endocrine disrupting chemicals (EDCs). The frog olfactory system substantially remodels during TH-dependent metamorphosis and the objective of the present study is to examine olfactory system gene expression for TH biomarkers that can evaluate the biological effects of complex mixtures such as municipal wastewater. We first examine classic TH-response gene transcripts using reverse transcription-quantitative real-time polymerase chain reaction (RT-qPCR) in the olfactory epithelium (OE) and olfactory bulb (OB) of premetamorphic Rana (Lithobates) catesbeiana tadpoles after 48 h exposure to biologically-relevant concentrations of the THs, 3,5,3'-triiodothyronine (T3) and L-thyroxine (T4), or 17-beta estradiol (E2); a hormone that can crosstalk with THs. As the OE was particularly sensitive to THs, further RNA-seq analysis found >30,000 TH-responsive contigs. In contrast, E2 affected 267 contigs of which only 57 overlapped with THs suggesting that E2 has limited effect on the OE at this developmental phase. Gene ontology enrichment analyses identified sensory perception and nucleoside diphosphate phosphorylation as the top affected terms for THs and E2, respectively. Using classic and additional RNA-seq-derived TH-response gene transcripts, we queried TH-disrupting activity in municipal wastewater effluent from two different treatment systems: anaerobic membrane bioreactor (AnMBR) and membrane enhanced biological phosphorous removal (MEBPR). While we observed physical EDC removal in both systems, some TH disruption activity was retained in the effluents. This work lays an important foundation for linking TH-dependent gene expression with olfactory system function in amphibians.

A Bayesian group sparse multi-task regression model for imaging genetics

MOTIVATION

Recent advances in technology for brain imaging and high-throughput genotyping have motivated studies examining the influence of genetic variation on brain structure. Wang et al. have developed an approach for the analysis of imaging genomic studies using penalized multi-task regression with regularization based on a novel group l2,1-norm penalty which encourages structured sparsity at both the gene level and SNP level. While incorporating a number of useful features, the proposed method only furnishes a point estimate of the regression coefficients; techniques for conducting statistical inference are not provided. A new Bayesian method is proposed here to overcome this limitation.

RESULTS

We develop a Bayesian hierarchical modeling formulation where the posterior mode corresponds to the estimator proposed by Wang et al. and an approach that allows for full posterior inference including the construction of interval estimates for the regression parameters. We show that the proposed hierarchical model can be expressed as a three-level Gaussian scale mixture and this representation facilitates the use of a Gibbs sampling algorithm for posterior simulation. Simulation studies demonstrate that the interval estimates obtained using our approach achieve adequate coverage probabilities that outperform those obtained from the nonparametric bootstrap. Our proposed methodology is applied to the analysis of neuroimaging and genetic data collected as part of the Alzheimer's Disease Neuroimaging Initiative (ADNI), and this analysis of the ADNI cohort demonstrates clearly the value added of incorporating interval estimation beyond only point estimation when relating SNPs to brain imaging endophenotypes.

AVAILABILITY AND IMPLEMENTATION

Software and sample data is available as an R package 'bgsmtr' that can be downloaded from The Comprehensive R Archive Network (CRAN).

CONTACT

nathoo@uvic.ca.

SUPPLEMENTARY INFORMATION

Supplementary data are available at Bioinformatics online.

Performance of a RT-PCR Assay in Comparison to FISH and Immunohistochemistry for the Detection of ALK in Non-Small Cell Lung Cancer

Patients with lung cancers harboring an activating anaplastic lymphoma kinase (ALK) rearrangement respond favorably to ALK inhibitor therapy. Fluorescence in situ hybridization (FISH) and immunohistochemistry (IHC) are validated and widely used screening tests for ALK rearrangements but both methods have limitations. The ALK RGQ RT-PCR Kit (RT-PCR) is a single tube quantitative real-time PCR assay for high throughput and automated interpretation of ALK expression. In this study, we performed a direct comparison of formalin-fixed paraffin-embedded (FFPE) lung cancer specimens using all three ALK detection methods. The RT-PCR test (diagnostic cut-off ΔC_t of ≤8) was shown to be highly sensitive (100%) when compared to FISH and IHC. Sequencing of RNA detected full-length ALK transcripts or EML4-ALK and KIF5B-ALK fusion variants in discordant cases in which ALK expression was detected by the ALK RT-PCR test but negative by FISH and IHC. The overall specificity of the RT-PCR test for the detection of ALK in cases without full-length ALK expression was 94% in comparison to FISH and sequencing. These data support the ALK RT-PCR test as a highly efficient and reliable diagnostic screening approach to identify patients with non-small cell lung cancer whose tumors are driven by oncogenic ALK.

Applying STOPP Guidelines in Primary Care Through Electronic Medical Record Decision Support: Randomized Control Trial Highlighting the Importance of Data Quality

Background

Potentially Inappropriate Prescriptions (PIPs) are a common cause of morbidity, particularly in the elderly.

Objective

We sought to understand how the Screening Tool of Older People’s Prescriptions (STOPP) prescribing criteria, implemented in a routinely used primary care Electronic Medical Record (EMR), could impact PIP rates in community (non-academic) primary care practices.

Methods

We conducted a mixed-method, pragmatic, cluster, randomized control trial in research naïve primary care practices. Phase 1: In the randomized controlled trial, 40 fully automated STOPP rules were implemented as EMR alerts during a 16-week intervention period. The control group did not receive the 40 STOPP rules (but received other alerts). Participants were recruited through the OSCAR EMR user group mailing list and in person at user group meetings. Results were assessed by querying EMR data PIPs. EMR data quality probes were included. Phase 2: physicians were invited to participate in 1-hour semi-structured interviews to discuss the results.

Results

In the EMR, 40 STOPP rules were successfully implemented. Phase 1: A total of 28 physicians from 8 practices were recruited (16 in intervention and 12 in control groups). The calculated PIP rate was 2.6% (138/5308) (control) and 4.11% (768/18,668) (intervention) at baseline. No change in PIPs was observed through the intervention (P=.80). Data quality probes generally showed low use of problem list and medication list. Phase 2: A total of 5 physicians participated. All the participants felt that they were aware of the alerts but commented on workflow and presentation challenges.

Conclusions

The calculated PIP rate was markedly less than the expected rate found in literature (2.6% and 4.0% vs 20% in literature). Data quality probes highlighted issues related to completeness of data in areas of the EMR used for PIP reporting and by the decision support such as problem and medication lists. Users also highlighted areas for better integration of STOPP guidelines with prescribing workflows. Many of the STOPP criteria can be implemented in EMRs using simple logic. However, data quality in EMRs continues to be a challenge and was a limiting step in the effectiveness of the decision support in this study. This is important as decision makers continue to fund implementation and adoption of EMRs with the expectation of the use of advanced tools (such as decision support) without ongoing review of data quality and improvement.

Trial Registration

Clinicaltrials.gov NCT02130895; https://clinicaltrials.gov/ct2/show/NCT02130895 (Archived by WebCite at http://www.webcitation.org/6qyFigSYT)

Effect of Referral Patterns and Treatment Type on Oncologic Outcomes for Women with Ductal Carcinoma In Situ

Objective

Management of ductal carcinoma in situ (DCIS) remains controversial. This study examined long-term outcomes in a population-based cohort of patients with pure DCIS treated with breast-conserving surgery (BCS) alone, BCS + radiotherapy (RT), and mastectomy. Outcomes were compared between patients referred versus not referred for oncologic assessment after definitive surgery.

Materials and methods

Subjects were 2575 women diagnosed between 1985 and 1999. Data from several electronic databases were linked and analyzed. Outcomes were invasive local recurrence-free survival (ILRFS), mastectomy-free survival (MFS), breast cancer-specific survival (BCSS), and overall survival (OS).

Results

Median follow-up time was 9.8 years. Overall, 56% (n = 1448) of subjects were referred to a cancer centre. Factors associated with non-referral were older age, comorbidities, and travel distance. Ten-year MFS, BCSS, and OS were higher among referred patients (all p ≤ 0.001). In cohorts treated with BCS alone (n = 1314) vs. BCS + RT (n = 510) vs. mastectomy (n = 751), 10-year ILRFS were 93.7% vs. 96.6% vs. 97.7%, (p < 0.001) and BCSS were 97.6% vs. 99.8% vs. 98.6%, (p = 0.01). Corresponding rates of ipsilateral invasive breast relapse at 10 years were 6.3% after BCS alone, 3.4% after BCS + RT, and 2.3% after mastectomy (p < 0.001). On multivariable analysis, factors associated with improved ILRFS were older age at diagnosis, low comorbidity score, absence of comedo histology, mastectomy, and post-BCS RT.

Conclusion

Patients with DCIS referred for oncologic assessment were more likely to undergo post-BCS RT, resulting in lower mastectomy and higher survival rates compared to non-referred patients. Patients with significant comorbidities were less likely to be referred and experienced lower ILRFS and BCSS. Referral for multidisciplinary oncologic assessment after surgery is warranted to individualize management and optimize outcomes for patients with DCIS.

Abstract P1-11-01: The effect of close and positive surgical margins on 10-year local recurrence and survival outcomes in women treated with breast conserving surgery plus adjuvant radiotherapy

This abstract was withdrawn by the authors.

Implementation of Novel Design Features for qPCR-Based eDNA Assessment

Environmental stewardship requires timely, accurate information related to the status of a given ecosystem and the species that occupy it. Recent advances in the application of the highly sensitive real-time quantitative polymerase chain reaction (qPCR) towards identification of constituents within environmental DNA (eDNA) now allow targeted detection of the presence of species-specific biological material within a localized geographic region. However, as with all molecular techniques predicated on the specificity and sensitivity of the PCR assay, careful validation of each eDNA qPCR assay in development must be performed both under controlled laboratory conditions and when challenged with field-derived eDNA samples. Such a step-wise approach forms the basis for incorporation of innovative qPCR design features that strengthen the implementation and interpretation of the eDNA assay. This includes empirical determination that the qPCR assay is refractory to the presence of human DNA and the use of a tripartite assay approach comprised of 1) a primer set targeting plant chloroplast that evaluates the presence of amplifiable DNA from field samples to increase confidence in a negative result, 2) an animal group primer set to increase confidence in the assay result, and 3) a species-specific primer set to assess presence of DNA from the target species. To demonstrate this methodology, we generated eDNA assays specific for the North American bullfrog (Lithobates (Rana) catesbeiana) and the Rocky Mountain tailed frog (Ascaphus montanus) and characterized each with respect to detection sensitivity and specificity with demonstrated performance in a field survey scenario. The qPCR design features presented herein address specific challenges of eDNA assays thereby increasing their interpretative power.

Assessing Conformance with Benford's Law: Goodness-Of-Fit Tests and Simultaneous Confidence Intervals

Benford’s Law is a probability distribution for the first significant digits of numbers, for example, the first significant digits of the numbers 871 and 0.22 are 8 and 2 respectively. The law is particularly remarkable because many types of data are considered to be consistent with Benford’s Law and scientists and investigators have applied it in diverse areas, for example, diagnostic tests for mathematical models in Biology, Genomics, Neuroscience, image analysis and fraud detection. In this article we present and compare statistically sound methods for assessing conformance of data with Benford’s Law, including discrete versions of Cramér-von Mises (CvM) statistical tests and simultaneous confidence intervals. We demonstrate that the common use of many binomial confidence intervals leads to rejection of Benford too often for truly Benford data. Based on our investigation, we recommend that the CvM statistic Ud2, Pearson’s chi-square statistic and 100(1 − α)% Goodman’s simultaneous confidence intervals be computed when assessing conformance with Benford’s Law. Visual inspection of the data with simultaneous confidence intervals is useful for understanding departures from Benford and the influence of sample size.

The NARC (Nonsteroidal Anti-inflammatory in Renal Colic) Trial. Single-dose intravenous ketorolac versus titrated intravenous meperidine in acute renal colic: a randomized clinical trial

Objectives:

Intravenous (IV) opioid titration is an accepted method of relieving acute renal colic. Studies have shown that nonsteroidal anti-inflammatory drugs (NSAIDs) are also effective in this setting. Our objective was to compare single-dose ketorolac and titrated meperidine, both administered intravenously, with respect to speed and degree of analgesia, adverse effects and functional status. Our primary hypothesis was that these agents provide equivalent analgesia within 60 minutes. Our secondary hypotheses were that ketorolac-treated patients would experience fewer adverse effects and would be better able to resume usual activity.

Methods:

This was a multicentre, double-blind randomized equivalence trial in a convenience sample of patients age 18–65 with moderate or severe renal colic, documented by intravenous pyelogram, ultrasound or stone passage. Meperidine-treated patients received 50 mg IV meperidine at 0 minutes, then 25–50 mg every 15 minutes as needed for ongoing pain. Ketorolac-treated patients received 30 mg IV ketorolac at 0 minutes and placebo injections every 15 minutes as needed. Pain levels and adverse effects were assessed every 15 minutes, and functional status was evaluated at 60 minutes. Our primary outcome was the proportion of patients with mild or no pain at 60 minutes.

Results:

Overall, 49 of 77 meperidine-treated patients (64%; 95% confidence interval [CI], 53%–75%) and 47 of 65 ketorolac-treated patients (72%; 95% CI, 61%–83%) achieved successful pain relief at 60 minutes (pvalue for equivalence = 0.002). Ten percent of meperidine-treated patients and 44% of ketorolac-treated patients were able to resume usual activity at 60 minutes (p= 0.001).

Conclusions:

In the doses studied, single-dose IV ketorolac is as effective as titrated IV meperidine for the relief of acute renal colic and causes less functional impairment.

Identification of patients at very low risk of local recurrence after breast-conserving surgery

PURPOSE

To identify clinical and pathological factors that identify groups of women with stage I breast cancer with a 5-year risk of local recurrence (LR) ≤1.5% after breast-conserving therapy (BCS) plus whole-breast radiation therapy (RT).

METHODS AND MATERIALS

Study subjects were 5974 patients ≥50 years of age whose cancer was diagnosed between 1989 and 2006, and were referred with pT1 pN0 invasive breast cancer treated with BCS and RT. Cases of 5- and 10-year LR were examined using Kaplan-Meier methods. Recursive partitioning analysis was performed in patients treated with and without endocrine therapy to identify combinations of factors associated with a 5-year LR risk ≤1.5%.

RESULTS

The median follow-up was 8.61 years. Median age was 63 years of age (range, 50 to 91). Overall 5-year LR was 1.5% (95% confidence interval [CI], 1.2%-1.9%) and 10-year LR was 3.4% (95% CI, 2.8%-4.0%). Of 2830 patients treated with endocrine therapy, patient subsets identified with 5-year LR ≤1.5% included patients with grade 1 histology (n=1038; LR, 0.2%; 95% CI, 0%-0.5%) or grade 2 histology plus ≥60 years of age (n=843; LR, 0.5%; 95% CI, 0%-1.0%). Ten-year LR for these groups were 0.8% (95% CI, 0.1%-1.6%) and 0.9% (95% CI, 0.2%-1.6%), respectively. Of 3144 patients treated without endocrine therapy, patients with grade 1 histology plus clear margins had 5-year LR ≤1.5% (n=821; LR, 0.6%; 95% CI, 0.1%-1.2%). Ten-year LR for this group was 2.2% (95% CI, 1.0%-3.4%).

CONCLUSIONS

Histologic grade, age, margin status, and use of endocrine therapy identified 45% of a population-based cohort of female patients over age 50 with stage I breast cancer with a 5-year LR risk ≤1.5% after BCS plus RT. Prospective study is needed to evaluate the safety of omitting RT in patients with such a low risk of LR.

Local recurrence in women with stage I breast cancer: declining rates over time in a large, population-based cohort

PURPOSE

To evaluate whether local recurrence (LR) risk has changed over time among women with stage I breast cancer treated with breast-conserving therapy.

METHODS AND MATERIALS

Subjects were 5974 women aged ≥50 years diagnosis with pT1N0 breast cancer from 1989 to 2006, treated with breast-conserving surgery and radiation therapy. Clinicopathologic characteristics, treatment, and LR outcomes were compared among 4 cohorts stratified by year of diagnosis: 1989 to 1993 (n=1077), 1994 to 1998 (n=1633), 1999 to 2002 (n=1622), and 2003 to 2006 (n=1642). Multivariable analysis was performed, with year of diagnosis as a continuous variable.

RESULTS

Median follow-up time was 8.6 years. Among patients diagnosed in 1989 to 1993, 1994 to 1998, 1999 to 2002, and 2003 to 2006, the proportions of grade 1 tumors increased (16% vs 29% vs 40% vs 39%, respectively, P<.001). Surgical margin clearance rates increased from 82% to 93% to 95% and 88%, respectively (P<.001). Over time, the proportions of unknown estrogen receptor (ER) status decreased (29% vs 10% vs 1.2% vs 0.5%, respectively, P<.001), whereas ER-positive tumors increased (56% vs 77% vs 86% vs 86%, respectively, P<.001). Hormone therapy use increased (23% vs 23% vs 62% vs 73%, respectively, P<.001), and chemotherapy use increased (2% vs 5% vs 10% vs 13%, respectively, P<.001). The 5-year cumulative incidence rates of LR over the 4 time periods were 2.8% vs 1.7% vs 0.9% vs 0.8%, respectively (Gray's test, P<.001). On competing risk multivariable analysis, year of diagnosis was significantly associated with decreased LR (hazard ratio, 0.92 per year, P=.0003). Relative to grade 1 histology, grades 2, 3, and unknown were associated with increased LR. Hormone therapy use was associated with reduced LR.

CONCLUSION

Significant changes in the multimodality management of stage I breast cancer have occurred over the past 2 decades. More favorable-risk tumors were diagnosed, and margin clearance and systemic therapy use increased. These changes contributed to the observed declining LR rates among patients treated with breast-conserving therapy.

Metabolomic insights into system-wide coordination of vertebrate metamorphosis

Background

After completion of embryogenesis, many organisms experience an additional obligatory developmental transition to attain a substantially different juvenile or adult form. During anuran metamorphosis, the aquatic tadpole undergoes drastic morphological changes and remodelling of tissues and organs to become a froglet. Thyroid hormones are required to initiate the process, but the mechanism whereby the many requisite changes are coordinated between organs and tissues is poorly understood. Metabolites are often highly conserved biomolecules between species and are the closest reflection of phenotype. Due to the extensive distribution of blood throughout the organism, examination of the metabolites contained therein provides a system-wide overview of the coordinated changes experienced during metamorphosis. We performed an untargeted metabolomic analysis on serum samples from naturally-metamorphosing Rana catesbeiana from tadpoles to froglets using ultraperformance liquid chromatography coupled to a mass spectrometer. Total and aqueous metabolite extracts were obtained from each serum sample to select for nonpolar and polar metabolites, respectively, and selected metabolites were validated by running authentic compounds.

Results

The majority of the detected metabolites (74%) showed statistically significant abundance changes (p_adj < 0.001) between metamorphic stages. We observed extensive remodelling of five core metabolic pathways: arginine and purine/pyrimidine, cysteine/methionine, sphingolipid, and eicosanoid metabolism and the urea cycle, and found evidence for a major role for lipids during this postembryonic process. Metabolites traditionally linked to human disease states were found to have biological linkages to the system-wide changes occuring during the events leading up to overt morphological change.

Conclusions

To our knowledge, this is the first wide-scale metabolomic study of vertebrate metamorphosis identifying fundamental pathways involved in the coordination of this important developmental process and paves the way for metabolomic studies on other metamorphic systems including fish and insects.

"Out-gel" tryptic digestion procedure for chemical cross-linking studies with mass spectrometric detection

SDS-PAGE is one of the most powerful protein separation techniques, and in-gel digestion is the leading method for converting proteins separated by SDS-PAGE into peptides suitable for mass spectrometry-based proteomic studies. In in-gel digestion, proteins are digested within the gel matrix, and the resulting peptides are extracted into an appropriate buffer. Transfer of the digested peptides to the liquid phase for subsequent mass spectrometric analysis, however, may be hampered by peptide-specific characteristics, including size, shape, poor solubility, adsorption to the polyacrylamide, and-in the case of cross-linking applications-by the branched structure of the peptides produced. This can be a limitation in cross-linking studies where efficient recoveries of the cross-linked peptides are critical. To overcome this limitation, we have developed a modification to the standard in-gel digestion procedure for SDS-PAGE-separated cross-linked proteins, based on older passive diffusion methods. By omitting the gel staining and gel fixation steps, intact proteins or cross-linked protein complexes can move through the gel and into the buffer solution. Digestion of the entire protein in the buffer outside the gel increases the probability that most of the proteolytic peptides produced will be present in the final digest solution. The resulting peptide mixture is then freed of SDS and concentrated using SCX (strong cation exchange) zip-tips and analyzed by mass spectrometry. For standard protein identification studies and the recovery of noncross-linked peptides, the in-gel procedure outperformed the out-gel procedure, but for cross-linking studies with enrichable cross-linkers (such as CBDPS), the standard out-gel procedure allowed the recoveries of cross-links not recovered via the in-gel method. Labeling experiments showed that, with an enrichable cross-linker, 93% of the cross-links showed better or equal recoveries with the out-gel procedure, as compared to the in-gel procedure. It should be noted that this method is not designed to replace in-gel digestion for most proteomics applications. However, by using the out-gel method, we were able to detect twice as many interprotein CBDPS cross-links from the histone H2A/H2B complex as were found in the in-gel digested sample.

Training mid-level providers on palliative care: bringing advanced directives and symptom assessment and management to community oncology practices

Palliative care services are not available in most outpatient oncology practices. A program training 11 mid-level providers from oncology practices on advanced directive discussions and supportive symptom assessment and management performed by palliative care specialists was completed. A follow-up session 9 months later identified barriers to implementation. Of the 11 mid-level providers, 8 participated in the follow-up session, and 9 of the 11 providers implemented advanced directive's discussions and symptom assessment and management for patients with metastatic cancer. Main barriers included uncertainties about reimbursement, patients' lack of knowledge about palliative care, and lack of access to supportive services. This program successfully promoted advanced directive discussions and supportive/palliative care symptom assessment and management to community oncology practices, which will hopefully translate into improved quality of life for patients with metastatic cancer.

Randomized study evaluating testosterone recovery using short-versus long-acting luteinizing hormone releasing hormone agonists

Introduction: We sought to compare the rate of return of testosteronelevels and sexual function in men with prostate cancerreceiving longer acting, 3-month preparation of luteinizing hormone-releasing hormone agonist (L-LHRH-A) versus shorter acting,1-month preparation of luteinizing hormone-releasing hormoneagonist (S-LHRH-A).Methods and Materials: Men with low to intermediate risk localizedprostate cancer were randomized to either L-LHRH-A (2-3 monthduration LHRH-A) or S-LHRH-A (6-1 month duration LHRH-A) ofandrogen suppression therapy (AST) and prostate brachytherapyusing iodine-125 radioisotopes. Serum total testosterone levels andPSA were recorded every 2 months for 2 years.Results: A planned target sample size of 100 was not achieveddue to insufficient accrual. A total of 55 patients were randomizedand 46 were used for analysis. The median time to recovery oftestosterone to baseline levels (calculated from end of AST) was 8and 4 months in the L-LHRH-A and S-LHRH-A arms, respectively(p = 0.268). The median time to testosterone recovery to lower limitof reference range was 4 and 2 months respectively (p = 0.087).Interpretation: This randomized study, which failed to reachaccrual target, showed a trend towards more rapid recovery oftestosterone levels using shorter acting LHRH-A. Another randomizedstudy would be required to validate these findings. Currently,there is insufficient evidence to recommend the use of shorteracting LHRH-A as a means of providing more rapid recovery oftestosterone levels.Introduction : Nous avons voulu comparer la vitesse de retourdes taux de testostérone et de la fonction sexuelle chez des hommesatteints d’un cancer de la prostate recevant un agoniste de laLHRH à longue durée d’action pendant 3 mois ou un agoniste dela LHRH à courte durée d’action pendant 1 mois.Matériel et méthodologie : Des hommes atteints d’un cancer dela prostate localisé avec risque faible à intermédiaire ont été randomiséspour recevoir soit un agoniste de la LHRH à longue duréed’action (2 doses trimestrielles) soit un antagoniste de la LHRHà courte durée d’action (6 doses mensuelles) comme traitementantiandrogène et une brachythérapie prostatique avec des radioisotopesde l’iode 125. Les taux sériques de testostérone totale etd’APS ont été notés tous les 2 mois pendant 2 ans.Résultats : L’échantillon prévu au départ de 100 patients n’apu être obtenu en raison d’un recrutement insuffisant. Au total,55 patients ont été randomisés et 46 ont été inclus dans les analyses.L’intervalle médian de retour à des taux normaux de testostérone(calculés à partir de la fin du traitement antiandrogène) étaitde 8 et 4 mois dans les groupes sous agoniste de la LHRH à longueet à courte durée d’action, respectivement (p = 0,268). L’intervallemédian requis pour que les taux de testostérone atteignent la limiteinférieure des valeurs de référence était de 4 et 2 mois, respectivement(p = 0,087).Interprétation : Cette étude randomisée, où on n’a pas réussi àobtenir le nombre de patients voulu, a montré une tendance vers unretour plus rapide des taux de testostérone avec un traitement paragoniste de la LHRH à courte durée d’action. Une autre étude randomiséeserait nécessaire pour valider ces résultats. Actuellement,on ne dispose pas de suffisamment de données pour recommanderun agoniste de la LHRH à courte durée d’action comme moyenpour ramener les taux de testostérone plus rapidement à la normale.

Conversion of Karnofsky Performance Status (KPS) and Eastern Cooperative Oncology Group Performance Status (ECOG) to Palliative Performance Scale (PPS), and the interchangeability of PPS and KPS in prognostic tools

AIM

The aim of our study was to assess whether the Karnofsky Performance Status (KPS), the Eastern Cooperative Oncology Group (ECOG) Performance Status, and the Palliative Performance Scale (PPS) are interchangeable individually or within two prognostic tools: the Palliative Prognostic Score (PaP) and the Palliative Prognostic Index (PPI).

METHODS

We performed a subset analysis of a prospective comparative study of functional and prognostic tools and clinician prediction of survival. We studied 955 patients with advanced life-limiting illnesses (cancer and noncancer) in the acute care and community settings. We used a descriptive statistical model and Spearman's rank correlation to assess these interchangeabilities.

RESULTS

There is a direct positive linear relationship between the KPS and the PPS, and a direct negative linear relationship between these tools and the ECOG. Exchange of the KPS and the PPS was possible within the PaP and the PPI.

CONCLUSION

The PPS and the KPS can be used interchangeably as functional tools and within prognostic tools. The ECOG is interchangeable with the PPS and the KPS, but this interchangeability is population-specific.

Toward a population-based approach to end-of-life care surveillance in Canada: initial efforts and lessons

This paper describes a project undertaken by the Hospice Palliative End-of-Life Care Surveillance Team Network--one of four Cancer Surveillance and Epidemiology Networks established by the Canadian Partnership Against Cancer in 2009 to create information products that can be used to inform cancer control. The project was designed to improve the quality and use of existing electronic patient databases in its member organizations. The project's intent was to better understand terminally ill cancer patients in their final year of life, with noncancer as comparison. The network created an early design for a Web-based end-of-life care surveillance system prototype. Using a flagging process, anonymized data sets on cancer/ noncancer palliative patients and those who died in 2008-2009 were extracted and analyzed. The Australian palliative approach was adapted as the conceptual model based on the data sets available. Common data elements were defined then mapped to local data sets to create a common data set. Information products were created as online reports. Throughout the project, members were engaged in knowledge translation. Overall, the project was well received by network members. There are still major data-quality and linkage issues that require further work.

Developing a multivariate electronic medical record integration model for primary health care

This paper describes the development of a multivariate electronic medical record (EMR) integration model for the primary health care setting. Our working hypothesis is that an integrated EMR is associated with high quality primary health care. Our assumption is that EMR integration should be viewed as a form of complex intervention with multiple interacting components that can impact the quality of care. Depending on how well the EMR is integrated in the practice setting, one can expect a corresponding change in the quality of care as measured through a set of primary health care quality indicators. To test the face validity of this model, a Delphi study is being planned where health care providers and information technology professionals involved with EMR adoption are polled for their feedback. This model has the potential to quantify and explain the factors that influence successful EMR integration to improve primary health care.

Reliability and validity of the Thai translation (Thai PPS Adult Suandok) of the Palliative Performance Scale (PPSv2)

PURPOSE

the Thai PPS Adult Suandok tool was translated from the Palliative Performance Scale (PPSv2) and had been used in Chiang Mai, Thailand for several years.

AIM

to test the reliability and validity of the Thai translation of PPSv2.

DESIGN

a set of 22 palliative cases were used to determine a PPS score on Time-1, and repeated two weeks later as Time-2. A survey questionnaire was also completed for qualitative analysis.

PARTICIPANTS

a total of 70 nurses and physicians from Maharaj Nakorn Hospital in Chiang Mai participated.

RESULTS

The Time-1 intraclass correlation coefficient (ICC) for absolute agreement is 0.911 (95% CI 0.86-0.96) and for consistency is 0.92 (95% CI 0.87-0.96). The Time-2 ICC for agreement is 0.905 (95% CI 0.85-0.95) and for consistency is 0.912 (95% CI 0.86-0.96). These findings indicate good agreement among participants and also were somewhat higher in the Time-2 re-test phase. Cohen's kappa score is 0.55, demonstrating a moderate agreement. Thematic analysis from the surveys showed that 91% felt PPS to be a valuable clinical tool overall, with it being 'very useful' or 'useful' in several areas, including care planning (78% and 20%), disease monitoring (69% and 27%) and prognostication (61% and 31%), respectively. Some respondents noted difficulty in determining appropriate scores in paraplegic patients or those with feeding tubes, while others found the instructions long or difficult.

CONCLUSION

the Thai PPS Adult Suandok translated tool has good inter- and intra-rater reliability and can be used regularly for clinical care.