Integrating Patient-Reported Outcomes Into Prognostication in Gastroesophageal Cancer: Results of a Population-Based Retrospective Cohort Analysis

BACKGROUND

Patient-reported outcomes measures (PROM) are self-reflections of an individual's physical functioning and emotional well-being. The Edmonton Symptom Assessment Scale (ESAS) is a simple and validated PRO tool of 10 common symptoms and a patient-reported functional status (PRFS) measure. The prognostic value of this tool is unknown in patients with gastroesophageal cancer (GEC). In this study, we examined the association between the ESAS score and overall survival (OS) in patients with GEC, the prognostication difference between ESAS and Eastern Cooperative Oncology Group (ECOG), and assessed the correlation between PRFS and the physician-reported ECOG performance status (PS).

METHODS

The study was a retrospective cohort study of 211 patients with GEC with localized (stages I-III) and metastatic disease who completed at least one baseline ESAS prior to treatment. Patients were grouped into 3 cohorts based on ESAS score. OS was assessed using the Kaplan-Meier method, and the concordance index (c-index) was calculated for ESAS and physician-reported ECOG. The agreement between PRFS and physician-ECOG was also assessed.

RESULTS

In total, 211 patients were included. The median age was 60.8 years; 90% of patients were ECOG PS 0-1; 38% of patients were stages I-III, while 62% were de novo metastatic patients. Median OS in low, moderate, high symptom burden (SB) patients' cohorts was 19.17 m, 16.39 mm, and 12.68 m, respectively (P < .04). The ability to predict death was similar between physician-ECOG and ESAS (c-index 0.56 and 0.5753, respectively) and PRFS and physician-ECOG (c-index of 0.5615 and 0.5545, respectively). The PS agreement between patients and physicians was 50% with a weighted Kappa of 0.27 (95% CI: 0.17-0.38).

CONCLUSION

Patient's SB seems to carry a prognostic significance. ESAS and physician-reported ECOG exhibit comparable prognostic values. Physicians and patients can frequently have divergent opinions on PS. ESAS takes a patient-centered approach and should be encouraged in practice among patients with GEC as an additional tool for prognostication.

Integrating patient-reported-outcomes into prognostication in gastroesophageal cancer: Results of a population-based retrospective cohort analysis

320

Background: Patient reported outcomes (PRO) measures are accurate self-reflections of an individual’s physical functioning and emotional well-being. The prognostic value is unknown in gastroesophageal (GE) cancer patients (pts). The Edmonton Symptom Assessment Scale (ESAS) is a simple and validated 10-item PRO tool which uses a 0 to 10 rating of ten common symptoms (total rating 0-100). In this study, we examined the association between the ESAS score and overall survival (OS) in pts with localized and metastatic GE adenocarcinoma (GEA). Methods: This study is based on the retrospective cohort database of pts with localized (stage I-III) and metastatic GEA. We included pts who were diagnosed with GEA between 2011 and 2021 and completed at least 1 baseline ESAS prior to the treatment. Pts were grouped into 3 cohorts based as follows: High symptom burden (SB) ESAS score ≥ 26, Moderate SB (11-25) or low SB (0-10). OS was defined as time from the first visit date to death. OS was assessed using the Kaplan-Meier method and significance was set at 2-sided P < 0.05. Univariate statistical analyses were used to examine the relationships between OS and multiple variables in the presentation. Results: 233 pts met the inclusion criteria: median age was 60.8y [51.4, 69.4]; 58% of pts were ECOG PS 1; 81% were non-Asian and 18.9% Asian; 67.4% of pts were male and 32.6% female. In terms of tumor location, gastric represented 47.2% of pts, GEJ 40.8% and esophageal 12.0% primaries; 43.7% pts were stage I-III, while 56.3% were de-novo metastatic pts. Median OS in Low, Mod, High SB pts cohorts were 22.7m, 17.6mm, & 14.6m, respectively (p < 0.036). Although worse OS and worse ESAS levels were not statistically significant in the localized pts (p, 505) and metastatic subgroup (p 0,092), there was a numerical tendency, especially in the metastatic pts. In the univariate analysis, there was a significant association between OS and high-symptom burden (Hazard ratio [HR] = 1.64 (95% CI, 1.12-2.38; p = 0.0104), ECOG ≥2 (HR= 2.79 (95% CI, 1.62-4.79; p = 0.0002) and metastatic pts (HR= 3.50 (95% CI, 2.51-4.86, p<0.0001). Conclusions: Higher SB based on ESAS was associated with poorer OS among GEA pts. ESAS is a reliable tool that carries a prognostic significance that could be used in practice.[Table: see text]

Pre-diagnostic delay among patients with curative esophageal and gastric cancer during the COVID-19 pandemic

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Background: The majority of esophageal and gastric cancers are diagnosed at an advanced stage with poor overall survival (OS), leading some to propose screening, even in countries with a low incidence. Whether diagnostic delay from symptom onset has any impact on OS is unclear. We investigated this question in the peri-COVID19 pandemic era. Methods: We retrospectively analyzed a cohort of 308 patients with esophageal, gastroesophageal junction, or gastric carcinoma treated with curative intent at the Princess Margaret Cancer Centre from January 2017 to December 2021. Clinical details pertaining to the initial presentation were determined through a retrospective chart review. OS was estimated using the Kaplan-Meier method. Cox proportional hazards regression models were used to assess the association between pre-diagnostic interval with OS adjusting for baseline patient characteristics. Results: The median interval from symptom onset to diagnosis was 98 days (IQR 47-169 days). Using a cox proportional hazard model, prolonged pre-diagnostic interval was not associated with worse OS (HR 1.00, P=0.62). Comparing patients diagnosed before and during the COVID19 pandemic, there was a notable increase in diagnostic delay with median pre-diagnostic interval increasing from 92 to 126 days (P=0.007). Median age at time of diagnosis was 69.6 during the pandemic vs 64.7 before the pandemic. Linear regression showed squamous cell histology was significantly associated with increasing time to initial diagnosis (P=0.04). Looking at other delay metrics, there were no changes in time interval from diagnosis to treatment during versus before the pandemic (median = 1.7 weeks for both), and there was no change in time from diagnosis to resection in those patients who underwent surgery. Conclusions: The COVID19 pandemic caused significant diagnostic delay for patients presenting with curative esophageal and gastric cancer. We found no evidence of pandemic-related health system delays in treatment, once a diagnosis was made. The lack of correlation of pre-diagnostic interval with OS may reflect underlying tumour biology as the driving force that determines prognosis.

Comparison of four clinical prognostic scores in patients with advanced gastric and esophageal cancer

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Background: While several clinical scoring systems exist to aid prognostication and patient (pt) selection for clinical trials in oncology, none are standardly used. We compared the ability of four prognostic scores to predict overall survival (OS) in pts with advanced gastric and esophageal (GE) cancer. Methods: Pts with advanced (unresectable or metastatic) GE cancer receiving first-line palliative-intent systemic therapy at the Princess Margaret Cancer Centre from 2007 to 2020 were included. High prognostic risk pts were identified using four scoring systems: Royal Marsden Hospital (RMH), MD Anderson Cancer Centre (MDACC), Gustave Roussy Immune Score (GRIm-S) and MD Anderson Immune Checkpoint Inhibitor (MDA-ICI) score. OS was estimated using the Kaplan-Meier method and compared between risk groups (high vs. not-high) for each scoring system using the log-rank test. Cox proportional hazards models were used to analyze the association between each prognostic score and OS, adjusting for baseline clinical factors. Harrell’s c-index was used to evaluate predictive discrimination of the models. Time-dependent AUCs were used to measure predictive ability for early death (within 90 days). Results: In total, 451 pts with advanced GE cancer were included. The median age was 59 years, 68% were male, 51% had ECOG status 0-1, 63% presented with de novo metastatic disease. The proportion of pts categorized as high risk was: RMH 25% (N=113), MDACC 13% (N=95), GRIm-S 24% (N=109), MDA-ICI 26% (N=117). In all scoring systems, high risk pts had significantly shorter OS (median OS 7.9 versus 12.2 months for RMH high vs. low risk, p<0.001; 6.8 vs. 11.9 months p<0.001 for MDACC; 5.3 vs. 13 months p<0.001 for GRIm-S; 8.2 vs. 12.2 months p<0.001 for MDA-ICI). On multivariable analysis, each prognostic score was significantly associated with OS (Table). The GRIm-S had the highest predictive discrimination (c-index 0.645 [0.612-0.678]) and highest predictive ability for early death (AUC 0.754 [0.675-0.832]). Conclusions: All four prognostic scoring systems compared had reasonable accuracy in predicting OS for patients with advanced GE cancer. The higher accuracy for predicting early death may render the GRIm-S as preferable. These tools can aid oncologists in discussions about prognosis, therapeutic decision-making and patient selection for clinical trials.[Table: see text]

Survival prediction using radiomic signatures in metastatic gastric and esophageal adenocarcinoma (GEA)

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Background: Radiomic characterisation of tumour phenotypes can generate image-driven biomarkers that potentially aid in clinical decision-making. We sought to identify radiomic features in metastatic GEA that may be predictive for survival outcomes. Methods: A retrospective analysis between 2009-20 identified patients (pts) with metastatic GEA. All pts received chemotherapy (CTx), with a ‘baseline’ and 8-12 week ‘on-treatment’ contrast-enhanced CT chest/abdomen/pelvis performed. Radiomic analysis was performed with LIFEx (livexsoft.org). Population demographics and clinical outcomes were recorded. Univariable Cox proportional hazards model (UVA) assessed clinical variables (n=26) predictive of overall survival (OS) and progression-free survival (PFS) with p=0.05 indicating significance. Multivariable Cox model (MVA) was used to assess radiomic features (n=78) in the presence of clinical variables. Concordance index (C-index) was calculated to assess model performance (≥0.7 = high predictive accuracy). A ‘validation’ cohort analysis was performed to validate the model. Results: 166 pts were identified (primary cohort n=143; validation cohort n=23). 123 had de-novo metastatic disease, 43 recurrence following curative-intent therapy. In the primary cohort the median age was 58.1y, 101 (71%) were male, 120 (84%) were non-Asian and 131 (92%) were ECOG 0-1. Similar demographics were observed in the validation cohort. Both ‘baseline’ and ‘on-treatment’ scans UVA identified Her2 status, ethnicity, and the number of CTx cycles as predictive of PFS, while ECOG, brain metastases, neutrophil count (ANC), albumin and number of CTx cycles were predictive of OS. ‘Baseline’ model analysis for PFS and OS identified consistent radiomic features (HUskewness; HUpeakSphere), with an observed C-index 0.6 and 0.657 respectively. No radiomic features were identified on ‘on-treatment’ PFS analysis. ‘On-treatment’ OS analysis is shown in the table with 3 radiomic features (SHAPE Surface; SHAPE Compacity; PARAMS ZSpatial-Resampling) predictive for OS. The C-index is 0.76. Analysis of the validation cohort supported the model (C-index 0.815) for ‘on-treatment’ OS. Conclusions: Radiomic analysis identified a number of features associated with PFS and OS. The features specifically identified on ‘on-treatment’ scans were highly predictive for OS. Our analysis suggests radiomic features in addition to clinical variables can be predictive of outcome in patients with metastatic GEA receiving CTx.[Table: see text]

Predictors of survival after metastasectomy of oligometastatic recurrence following gastroesophageal cancer treatment

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Background: Recurrent gastroesophageal (GE) carcinomas carry a poor prognosis and are usually treated with palliative chemotherapy (CTX). However, recent studies suggest that certain patients with oligometastatic recurrence can have long term survival after metastasectomy. Appropriate patient selection for metastasectomy remains a challenge, as few predictors of overall survival (OS) after metastasectomy have been identified. Our primary aim was to identify predictors of OS following metastasectomy in GE cancers. Methods: We conducted a retrospective study of GE cancer patients treated from 2007 to 2015 using the Princess Margaret Hospital Cancer Registry. We included patients who underwent curative-intent surgery or definitive chemoradiation (CRT) for localized GE cancer who then had single organ recurrence treated with metastasectomy. The probability of OS from date of recurrence was estimated with the Kaplan Meier method. Predictors of OS after metastasectomy for isolated recurrence were determined using Cox proportional hazards analysis. Covariates included time to recurrence (interval from curative-intent surgery or completion of definitive CRT), site of recurrence (lung/non-lung), sex, age and race (Asian/Non-Asian). Within the multivariable model, predictors with a p-value less than 0.05 were deemed significant. Results: Of 44 patients, median age was 58 years (28-78), and 59% were male. Primary sites were: esophagus 25%, GE junction 41% and gastric 34%. Treatment of the primary was: surgery alone 13%, surgery and (neo)adjuvant CTX 76%, and CRT 11%. Recurrent sites were brain 22%, ovary 20%, lung 18%, bone 7%, adrenals 7%, liver 7%, distant lymph node 6%, and other 13%. The median follow up time was 38.9 months. The 1, 3 and 5-year (yr) OS following metastasectomy were 79% (95% CI 68-92%), 40% (27-58%) and 28% (16-49%). Univariable analysis revealed that time to recurrence greater than 1 yr (HR=0.45 95% CI 0.21-0.93, p=0.032) and lung site recurrence (HR=0.16 95% CI 0.04-0.67, p=0.012) were associated with longer OS. On multivariable analysis, only lung site recurrence was significant (HR=0.12 95% CI 0.03-0.54, p=0.0056). The 1, 3 and 5-yr OS for patients after resection of isolated lung recurrence were 100% (95% CI 100-100%), 86% (63-100%) and 69% (40-100%). Conclusions: In our study, patients with isolated pulmonary recurrences demonstrated prolonged overall survival following metastasectomy. These patients could be considered for resection following recurrence of GE cancer. [Table: see text]

Gastric and gastroesophageal adenocarcinoma survival outcomes relative to completion of perioperative fluorouracil, leucovorin, oxaliplatin, and docetaxel (FLOT): A single-center retrospective analysis

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Background: Perioperative FLOT is standard-of-care for locally advanced resectable gastric and gastroesophageal (GEJ) adenocarcinoma. Completion of perioperative chemotherapy (8 cycles) is potentially jeopardised by significant toxicity and intolerance. Only 46% of patients completed all cycles in the initial phase 2/3 trial (FLOT-AIO). We sought to determine the rate of treatment completion in a real-world population and any subsequent impact on survival of incomplete treatment. Methods: A retrospective analysis of gastric and GEJ adenocarcinoma patients treated with perioperative FLOT at Princess Margaret Cancer Centre, Toronto between September 2017 and July 2020 was performed. The rate of perioperative FLOT administration, disease-free survival (DFS) and overall survival (OS) was analysed, with outcomes compared between patients that completed perioperative FLOT and those that didn’t. Results: 32 patients were identified as receiving neoadjuvant FLOT. Mean age was 61.5y, 26 (81%) were male and 29 (91%) were non-Asian. All patients were ECOG 0-1. The median number of neoadjuvant cycles was 4. 29 (91%) had surgery (2 = disease progression; 1 = declined surgery). 10 (34%) patients had minimal/nil response upon resection (College of American Pathologists Tumour Regression Grading (TRG) Score 3), 5 of whom received adjuvant FLOT whilst 5 did not (p0.28). 10 (34%) patients did not receive adjuvant FLOT, 18 (62%) did and 1 received 8 cycles of neoadjuvant chemotherapy. Nil demographic differences were observed between ‘yes’ and ‘no’ adjuvant FLOT groups. The reasons for not having adjuvant chemotherapy were: metastatic disease diagnosed post-operatively (n = 2), TRG Score 3 (n = 4), patient declined further chemotherapy (n = 1), reduced performance status and/or toxicity (n = 2), and the patient requiring treatment for a second malignancy (n = 2). 10 (34%) patients completed perioperative chemotherapy. Median DFS was 12.5m (95% CI 7.9-12.5) for ‘no’ FLOT’ and was not-reached for ‘yes’ FLOT (p = 0.29). 18m DFS was 50% (95% CI 27-93) v 81% (95% CI 64-100) respectively. The median OS for ‘no’ adjuvant FLOT was 16.7m (95% CI 11.5-16.7) with 5 deaths. Zero deaths due to malignancy had occurred at 23.3m in those who received adjuvant FLOT (p0.00164). 1 death in the ‘yes’ group occurred due to interstitial lung disease. Conclusions: In our small population size 34% of patients completed perioperative FLOT. Whilst nil statistically significant difference was observed in mDFS, an improved mOS was observed in those that received adjuvant FLOT suggesting an importance in receiving the maximum number of cycles of chemotherapy. Given the challenges of administering adjuvant FLOT future trials into the feasibility and efficacy of 8 cycles of neoadjuvant FLOT should be considered.

Impact of age on outcomes and symptoms in patients with advanced gastroesophageal cancer (GEC)

193

Background: Although age is a non-modifiable risk factor for most cancers, alone it is not very helpful in deciding on the best treatment for patients. Insufficient data exist in the oldest old ( > 75 years) compared to young-old (65-75 years) and to younger ( < 65 years) patients with de novo metastatic GEC regarding which factors influence response and outcomes. Methods: We retrospectively assessed all patients with de novo metastatic GEC seen from 2006-2015 at the Princess Margaret Cancer Center in Toronto-Ontario, Canada. We used Kaplan-Meier plots and Cox proportional hazards analyses to examine factors associated with progression-free survival (PFS) and overall survival (OS). To examine patient-reported outcomes we used the Edmonton Symptom Assessment System (ESAS) in the first six months of therapy using cross-sectional and longitudinal analyses. Results: A total of 580 de novo metastatic GEC patients were seen between 2006 and 2015. Of these (14%) were oldest old, (31%) were young-old (age 65-75) and 54% were younger ( < 65 years). Most patients (67-80%) were male. Median OS for the entire cohort was 9.1 mo. (95% confidence interval (CI) 8.0 – 10.1); the shortest OS was in the oldest old group at 4.5 mo. compared to 8.7 mo. in young-old and 9.8 mo. in younger group, p < 0.001. PFS was also significantly different among the age groups (4.4 mo., 6.1 mo., and 6.5 mo., respectively), p = 0.0145. In a multivariate model predictors for OS were age (young-old group), number of metastasis, and Eastern Cooperative Oncology Group (ECOG) performance scale (PS). Similar predictors were found for PFS; however, age was not a significant factor. Of the 55 patients who provided ESAS data, 58% were < 65 and 42% were age≥ 65. The most common symptoms at presentation were fatigue, appetite, and well-being. There were no differences by age group (all p > 0.05). Conclusions: Patients age > 75 have poorer OS compared to younger age groups but PFS does not differ, suggesting similar benefits with treatment in appropriately selected older adults with advanced GEC. Symptom profiles were similar with age. Further comprehensive care is needed for older patients with advanced GEC to improve their survival.

Pre-treatment psychoeducational intervention and outcomes in head and neck cancer patients undergoing radiotherapy

BACKGROUND

To investigate the relationship between attendance to a pre-treatment psychoeducational intervention (prehab) with treatment outcomes and toxicities in patients receiving radiotherapy for head and neck cancers (HNCs).

METHODS

Patients were included from prehab inception in 2013 to 2017, comparing overall survival (OS), locoregional recurrence-free survival (LRFS), and locoregional recurrence (LRR) between prehab attendees (PA) and non-attendees (PNA). Multivariable analysis was performed for OS and LRFS.

RESULTS

Among 864 PA and 1128 PNA, 2-year OS was 88% vs 80% (p < 0.001), and LRFS was 84% vs 75% (p < 0.001). On multivariable analysis (MVA), OS and LRFS were independently and unfavourably associated with PNA. The PA cohort had a lower frequency of a "rocky treatment course" compared with the PNA cohort (52/150, 35% vs 71/150, 47%; p = 0.034).

CONCLUSIONS

Prehab at our institution is associated with improved long-term oncologic outcomes. Prospective data is needed to better understand this association.

Prognostic significance of nutritional markers in metastatic gastric and esophageal adenocarcinoma

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Background: Malnutrition and sarcopenia (defined as low skeletal muscle mass) are recognized as poor prognostic factors in many cancers. Studies to date in gastroesophageal cancer have largely focused on patients (pts) undergoing curative intent surgery. This study aims to evaluate the prognostic utility of nutritional markers and sarcopenia in pts with de novo metastatic gastric and esophageal adenocarcinoma (GEA). Methods: Pts with de novo metastatic GEA seen at the Princess Margaret Cancer Centre from 2010-2016 with available pre-treatment abdominal computed tomography imaging were identified from an institutional database. Nutritional index (NRI) was calculated using weight and albumin, with moderate/severe malnutrition defined as NRI < 97.5. Skeletal muscle index (SMI) normalized by height was calculated at the L3 level using Slice-O-Matic software. Sarcopenia was defined as SMI < 34.4cm2/m2 in women and < 45.4cm2/m2 in men based on previously established consensus. Results: Of 175 consecutive pts, median age was 61, 69% were male, 79% had ECOG performance status 0-1, and 71% received chemotherapy. Median BMI was 24.2 (range 15.7-39.8), 70% of pts had > 5% weight loss in the preceding 3 months, and 29% had moderate/severe malnutrition. 68 pts (39%) were sarcopenic, of whom 46% were malnourished. Median overall survival (OS) was 9.3 months (95% CI 7.3-11.4) for all pts. OS was significantly worse in malnourished pts (5.5 vs 10.9 months, p = 0.000475) and displayed a non-significant trend in sarcopenic pts (7.8 vs 10.6 months, p = 0.186). On univariable Cox proportional hazards (PH) analysis, ECOG (p < 0.001), number of metastatic sites (p = 0.029) and NRI (p < 0.001) were significant prognostic factors, while BMI (p = 0.57) and sarcopenia (p = 0.19) were not. On multivariable Cox PH analysis, ECOG (p < 0.001) and NRI (p = 0.025) remained significant as poor prognostic factors for OS. Conclusions: This study demonstrates in a large cohort of de novo metastatic GEA pts that ECOG and NRI were significantly associated with poor OS. NRI was superior to BMI alone. Early identification of malnourished pts using NRI may allow for supportive interventions to optimize nutritional status. Further study is needed to determine whether these factors can be modified to improve prognosis in these pts.

Outcomes relative to paclitaxel dose-intensity when administered with ramucirumab in gastric and gastroesophageal junction (GEJ) adenocarcinoma

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Background: Combination paclitaxel (PTX) and ramucirumab (RAM) is standard second-line treatment for gastric and GEJ cancers. Peripheral neuropathy (PN) is considered a potential obstacle to administering a maximal dose of PTX, potentially limiting efficacy. We sought to determine the dose-intensity and outcomes for patients receiving this treatment. Methods: A retrospective analysis of gastric and GEJ cancer patients treated at Princess Margaret Cancer Centre (2012-2017) was performed identifying all patients who received PTX and RAM during their treatment course. The primary objective was to determine the dose-intensity of PTX administration. Secondary objectives included identification of the reason for dose-reduction (DR), and comparing progression-free survival (PFS) and overall survival (OS) in relation to PTX DR. Results: 45 patients were included in the study. Mean age was 57.2y, 34 (76%) were male, 7 (16%) were Asian, 5 (11%) patients were her2 positive. 42 (93%) patients received first-line treatment containing a potential neuro-toxic agent (cisplatin, oxaliplatin, docetaxel or paclitaxel). 22 (49%) subjects required PTX DR. The median number of cycles administered for subjects not requiring a DR and those with dose-reduced PTX was 3 v 6 (p < 0.001) respectively, with the median number of PTX doses administered 8 v 15 (p0.0022). The mean dose-intensity was 100 v 83% (p < 0.001). PN was the reason for DR in 32% (n = 7) of subjects, whilst neutropenia was 41% (n = 9). The reason for treatment cessation was disease progression in 91% of subjects, irrespective of whether they required a DR or not. Median PFS was 2.8m (95% CI 2.1-4.8) (100% dose PTX) and 5.5m (95% CI 4.8-8.6) in those requiring a DR (p0.0006). Median OS, measured from the initial diagnosis of incurable/metastatic disease was 16.4m (95% CI 13.7-22.9) and 18.5m (95% CI 14.9-47.5) respectively (p0.0953). Conclusions: Approximately half of the patients required a PTX DR, of whom a clinically significant 32% were DR due to PN, slightly less than those DR due to neutropenia. PFS was longer in those requiring a DR, which may reflect that those on treatment longer are more likely to experience toxicity and require a subsequent DR. PTX DR did not significantly affect OS, thus whilst PTX toxicity remains a clinical concern we did not identify that a DR resulted in an appreciable difference in treatment efficacy.

Clinicopathological features and treatment outcomes of young patients with gastric and esophageal cancers

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Background: Gastric and esophageal (GE) cancers most commonly occur in older adults in their 60’s.However, there are inconsistent reports about prognosis in adolescent and young adult (AYA) pts, and treatment patterns and outcomes in this population have not been well characterized. Methods: A retrospective analysis was performed for AYA (age 18-40 years) pts with histologic diagnosis of GE cancers who presented to Princess Margaret Cancer Centre from 2008 to 2016. The Kaplan-Meier method was used to analyze progression free (PFS) and overall survival (OS). Results: We identified 57 AYA GE cancer pts (30 gastric, 27 esophageal). Baseline features included: median age 35 years, 51% female (70% in gastric, 30% in esophageal), 82% with Eastern Cooperative Oncology Group performance status 0-1, 82% Charlson Comorbidity Index 0, 54% stage IV. For gastric pts, 53% had diffuse subtype and 47% had signet ring adenocarcinoma. Most had negative family history (77%). Curative intent and palliative treatment was used in 23 (40%) and 34 pts (60%) respectively. In curative pts, 48% had neoadjuvant therapy, 52% had upfront surgery. Of pts who underwent curative resection, 62% had pT3/T4 and 38% had pN2/N3 disease; 5-year OS rate was 37% (95% CI 20-67). Of the palliative pts, 91% received systemic therapy. First-line regimen included triplet (81%) and doublet chemotherapy (13%), administered for a median of 6 cycles. Median PFS was 7.4 months. Second- and third-line treatments were administered in 14 and 3 pts respectively, 1 pt was treated beyond third-line. Median OS in palliative pts was 12.1 months (95% CI 8-21.3). Conclusions: Our gastric AYA pts had increased female predominance and diffuse histology. Many AYA pts had advanced GE cancer at diagnosis, with over half of pts presenting with metastatic disease. In both the curative and palliative setting, AYA pts did not appear to have better survival outcomes despite having few comorbidities, suggesting they may have more aggressive biology.

Impact of body measurements (BM) on overall survival (OS) and quality of life (QoL) in real-world patients (pts) with metastatic esophageal cancer

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Background: Body fat and muscle influence prognosis in many cancer types. However, this association is unclear for real-world MEC pts, who are often in worse performance status than their previous baseline. In addition, the relationship of BM at presentation and QoL is unknown. We used real-world MEC pts to assess the importance of BM in OS and QoL. Methods: BM were done at baseline computed tomography in MEC pts, treated from 2006-2014 at the Princess Margaret Cancer Centre. Two radiologists (correlation 0.9-1.0) assessed L3 level using SliceOMatic to determine Skeletal Muscle Index (SMI - muscle area at L3 normalized by height), Visceral Adiposity Tissue (VAT), and Subcutaneous Adiposity Tissue (SAT). We used previously published cut-offs for sarcopenia based on sex and BMI, and the highest tertile as the cut-off for adiposity. We used prospectively collected QoL surveys including EuroQol 5D-5L (EQ5D) and the Functional Assessment of Cancer Therapy – Esophageal (FACT-E). Results: Of 200 pts, 164 (82%) were male, 180 (92%) were non-Asian; mean age was 62 y; ECOG: 0-1 = 142 (71%), 2 = 58 (29%); 69% had adenocarcinoma; 5% were underweight, 44% normal weight, 30% overweight, and 21% obese. 40 (20%) pts completed QoL measures. We found that 104 (52%) were sarcopenic at baseline, 66 (33%) had high VAT, and 67 (34%) had high SAT. A multivariable Cox model showed that sarcopenia and VAT were independent prognostic variables for three-year OS: sarcopenia increased the risk of death by 50% (adjusted hazard ratio, aHR 1.50, p 0.02), whereas every 100-cm2 increase in VAT improved OS by 24% (aHR 0.76, p 0.03). Finally, sarcopenic pts had significantly worse physical well-being (p 0.01) on FACT-E after adjusting for sex and age. Numerically, the EQ5D also showed lower scores in sarcopenic pts but this was not statistically significant (p 0.18). Conclusions: In MEC pts, sarcopenia and low visceral adiposity result in worse OS; sarcopenia is also significantly associated with poor QoL. Future work will need to focus on potential rehabilitation strategies such as nutritional support and exercise training to offset the poor prognosis associated with sarcopenia and reduced adiposity. [Table: see text]

Patterns of disease, treatment, and outcomes of esophageal cancer arising within a previous radiation treatment field

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Background: Esophageal cancer arising within a previous radiation treatment field (ECRF) is rare. The patterns of disease, treatment and outcomes in these patients (pts) have not been well characterized. Methods: A retrospective analysis was performed for pts treated for esophageal cancer at the Princess Margaret Cancer Centre from 2002-2016. Electronic medical records of all pts with a histologic diagnosis of esophageal cancer occurring within the field of previous radiotherapy were reviewed. The Kaplan-Meier method was used to calculate progression free survival (PFS) and overall survival (OS). Results: Of 31 ECRF pts identified, the most common prior cancer was head and neck (45%), median radiation (RT) dose 50Gy, median time to diagnosis of esophageal cancer 12 years. Features at diagnosis of ECRF included: median age 71 years, 58% male, 87% with performance status (PS) 0-1, 77% squamous cell carcinoma, 19% stage IV. Treatment intent was curative in 16 pts, palliative in 15 (Table). Reasons for palliative treatment were: 40% metastatic, 53% comorbidities/PS, 7% anatomic factors. Of resected pts, 36% had a pT1-2 tumour, 55% pN0, 69% R0. For curative pts, median PFS was 26.2 months (95%CI 10.9-34.4) with a 3 year PFS rate of 35% (95% CI 15-81). Median OS for curative pts was 26.4 months (95%CI 17.8-105.5) with a 3 year OS rate of 43% (95% CI 22-83). Most palliative pts were unable to have chemotherapy due to comorbidities and PS. Median OS for palliative pts was 9.5 months (95% CI 3.6-15.4). Conclusions: Most ECRF pts presented with earlier stage disease; however, more than a third of these could not have aggressive curative treatment due to comorbidities and/or PS. Most curative pts had surgery alone. Few palliative pts had chemotherapy, largely due to poor clinical status. Our data suggest that outcomes in both curative and palliative ECRF pts may be limited by the ability to tolerate standard of care treatments.

[Table: see text]

Blood-based-inflammation-markers, body mass index, and survival of nonmetastatic esophageal cancer

324

Background: Blood-based-inflammation-markers (BBIM) and Body Mass Index (BMI) have been associated with overall survival (OS) in a number of cancers. Inflammation and obesity have biological interactions. We evaluated the role of Neutrophil-to-Lymphocyte-Ratio (NLR), Platelet-to-Lymphocyte-Ratio (PLR) and Systemic-Inflammation-Index (SII) in conjunction with BMI as predictors of OS in localized/locally-advanced-esophageal cancer (LEC/LAEC). Methods: LEC/LAEC patients treated from 2006-2014 had the following variables analyzed both as continuous and categorical: BMI (low <25 kg/m2, high ≥25 kg/m2), NLR (low <4, high ≥4), PLR (low <232, high ≥232), and SII (low <1375, high ≥1375), with OS. Univariate (UVA) and Multivariate analysis (MVA) were analyzed using Cox regression (adjusted hazard ratios, aHR; 95% Confidence Intervals, CI). MVA models of OS were built, assessing different categorical combinations of BBIM factors with and without BMI. Results: Of 411 pts, 79% were males, median age was 63.5 years, 67% were adenocarcinomas; Stage I/II/III: 14%, 28%, 59%; Median BMI was 26.5kg/m2 and BMI distribution was: 3% underweight, 40% normal weight, 37% overweight and 20% obese. After a median follow-up of 87 months, 204 pts recurred, and 257 died. In MVA, BMI alone had no impact on OS (aHR 0.89, CI 0.7-1.1, p=0.15); individually as continuous variables, higher SII (p=0.03) and higher NLR (p=0.006) were inversely associated with OS whereas higher PLR was not (p=0.10). In an MVA of categorical combinations of BMI and BBIM on OS, patients in the high-BMI/low-PLR group were at lower risk of death when compared to all other groups (aHR=0.65, 95%CI:0.5-0.8, p=0.007). Similar non-statistically significant trends were shown when SII and NLR were individually combined with BMI (aHR=0.77, 95%CI:0.6-1.0, p=0.09; aHR=0.74, 95%CI:0.5-1.0, p=0.05, respectively). Conclusions: Our results suggest that in LEC/LAEC pts, high BMI and low PLR together are associated with improved OS when compared to pts with low BMI and/or high PLR. NLR and SII alone were associated with OS. Further studies evaluating the underlying mechanisms of BBMI, in particular PLR and inflammation/obesity are warranted.

Clinicopathological features and treatment outcomes of young patients with gastric and esophageal cancers

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Background: Gastric and esophageal (GE) cancers most commonly occur in older adults in their 60’s. There are inconsistent reports about prognosis in adolescent and young adult (AYA) pts, and treatment patterns and outcomes in this population have not been well characterized. Methods: A retrospective analysis was performed for AYA (age < 40) pts with GE cancers who presented to Princess Margaret Cancer Centre from 2008 to 2016. The Kaplan-Meier method was used to analyze progression free (PFS) and overall survival (OS). Results: We identified 57 AYA GE cancer pts (30 gastric, 27 esophageal). Features at diagnosis included: median age 35, 51% female (70% in gastric, 30% in esophageal), 82% with performance status 0-1, 83% Charlson Comorbidity Index 0, 54% stage IV. For gastric pts, 53% had diffuse histology and 47% had signet ring adenocarcinoma. There was a negative family history of gastric or esophageal cancer in 77% of pts. Curative intent treatment was used in 23 pts, palliative in 34. In curative pts, 48% had neoadjuvant therapy, 52% had upfront surgery. Of pts who underwent surgery, 57% had T3 or T4a disease and 38% had N2 or N3 disease. Median OS in curative pts was 39.9 months (95% CI 19.7-69.9), with a 5-year OS rate of 37% (95% CI 20-67). Of the palliative pts, 91% had chemotherapy. First line chemotherapy was a triplet regimen in 80%, doublet in 13%. The median number of treatment cycles on first line chemotherapy was 6, with a median PFS of 7.4 months (95% CI 5.4-10.5). At progression, 14 pts had second line treatment, 3 pts had third line and only 1 pt was treated beyond third line. Median OS in palliative pts was 12.1 months (95% CI 8-21.3). Conclusions: Consistent with the literature, our gastric AYA pts had increased female predominance and diffuse histology. Many AYA pts had advanced disease at diagnosis, with over half of pts presenting with metastatic disease. In both the curative and palliative setting, AYA pts did not have better survival outcomes despite being young with few comorbidities, suggesting they may have more aggressive biology.

Muscle wasting, visceral and subcutaneous adiposity, inflammation, nutritional deficiencies, and metastatic esophageal cancer (MEC) prognosis

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Background: MEC, associated with fatigue and dysphagia, leads to loss of skeletal muscle mass, malnutrition, subcutaneous and visceral adiposity. Cancer inflammation mobilizes muscle and adipose tissue, potentially leading to cachexia and sarcopenia. Supportive management depends on understanding the cancer frailty determinants that lead to poor outcomes. Methods: We retrospectively identified de novo MEC patients pts treated in Toronto, Canada (2007-2014). Body composition including visceral (VA) and subcutaneous adiposity (SA) at L3 level were assessed with baseline CT scans using SliceOMatic software by two outcome-blinded radiologists (Intraclass correlation, 0.92-1.00). Sarcopenia was assessed using Skeletal Muscle Index (SMI) with cut-offs defined either by optimized-stratification (OpS) or gender-dependent consensus cutoffs (GdC). Cox proportional hazard models generated adjusted hazard ratios (aHR). Results: Of 101 patients, 82% were male; 96% Caucasian; median age at diagnosis 61y (29-88); mean body mass index (BMI) 25.4; 69%/31% adeno/squamous cell carcinoma; median overall and progression free survival were: 6.4 (OS) and 3.9 mos (PFS). Median follow-up time was 5.6 mos. SMI-OpS and SMI-GdC were correlated (Rho = 0.67). Nutritional risk index, BMI, neutrophil-to-lymphocyte and neutrophil-to-platelet ratios were not associated with outcome (p > 0.20, each comparison). However, univariable analyses identified serum albumin, LDH, and either SMI-OpS or SMI-GdC as being associated with OS. In multivariable models, sarcopenia was associated with worse OS (SMI-OpS aHR = 1.93 (1.0-3.7) p = 0.046; SMI-GdC aHR = 2.30 (1.3-4.1) p = 0.004), and worse PFS (SMI-OpS aHR = 2.16 (1.2-4.0) p = 0.01; SMI-GdC aHR = 1.66 (1.0-2.9) p = 0.07)). In 55 pts receiving chemotherapy at diagnosis, less VA (p = 0.01) and SA (p = 0.02), as continuous variables, were associated with worse OS. Conclusions: Though no associations were found between nutritional deficiencies or inflammatory markers and prognosis, there was approximately a two-fold worse prognosis in the presence of sarcopenia, and associations with loss of adiposity. (JB/AFF/DR/MM contributed equally).

Impact of adjuvant chemotherapy and cumulative cisplatin dose in locally advanced nasopharyngeal carcinoma (LA-NPC) treated with definitive chemoradiotherapy

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Background: Total cumulative cisplatin dose (CDDP-D) (concurrent/induction/adjuvant) in multimodality therapy for LA-NPC has been associated with survival at centers in Asia. We evaluated the survival impact of adjuvant chemotherapy (adj chemo) and total CDDP-D in a large, single institution Canadian cohort of LA-NPC. Methods: Patients (Pts) withWHO type II and III LA-NPC treated with concurrent IMRT with high-dose CDDP and adj chemo with CDDP/Carboplatin and 5-FU (maximum total/adjuvant CDDP-D= 540/240 mg/m2) between 2003-2016 were analyzed. EBER status was tested by ISH. Staging was classified by UICC/AJCC7thedition TNM. Kaplan-Meier 5-year (5y) for overall survival (OS) and recurrence-free survival (RFS) were calculated and compared by log-rank test betweenstage, adj chemo (yes vs no) and total CDDP-D (>300 vs ≤300mg/m2). Multivariable analysis (MVA) identified survival predictors. Results: A total of 312 pts were evaluated: median age = 49.8 (range 17.4-75.9); EBER+/-/unknown=67%/1%/32%; stage II/III/IV=2%/51%/47%; T4=36%; N3=17%; adj chemo=83% (21% switched to carboplatin); median total/adjuvant CDDP-D=380/160 mg/m2; median follow-up 7.6 years (range 0.6-14.9). 5y OS differed by stage II-III vs IV (95% vs 80%, p<0.001) and total CDDP-D >300 vs ≤300mg/m2 (89% vs 83%, p=0.02). Adj chemo and total CDDP-D impacted 5y OS in stage IV (table). 5y RFS was higher in stage IV with total CDDP-D >300 vs ≤300mg/m2 (74% vs 59%, p=0.03), with a trend in locoregional control (LRC) (91% vs 80%, p=0.05) but not significant on distant control (DC) (78% vs 72%, p=0.36). Conclusions: Total CDDP-D >300 mg/m2 impacts OS in the overall cohort. The benefit of adj chemo and total CDDP-D on OS and RFS is significant in stage IV but not stage II-III LA-NPC, mainly due to higher LRC rather than DC. [Table: see text]

Prognostic significance of sarcopenia in metastatic esophageal squamous cell carcinoma

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Background: Sarcopenia is defined as low skeletal muscle mass and represents a quantifiable marker of frailty. Disease related symptoms of anorexia, nausea and dysphagia, in addition to reduced physical activity contribute to muscle wasting in metastatic esophageal squamous cell cancer (MESCC) patients. This study set out to evaluate the prognostic utility of sarcopenia and its association with nutritional indices. Methods: MESCC patients (pts) with available abdominal CT imaging, attending Princess Margaret Cancer Centre between 2011 and 2016, were identified from the institutional database. Skeletal muscle index (SMI), normalized by height, was calculated at the third lumbar (L3) vertebra using SliceOMatic software. SMI cutoffs for sarcopenia were 34.4cm2/m2 in females and 45.4cm2/m2 in males based on previously established consensus. Nutritional risk index (NRI) was calculated using weight and albumin with malnutrition defined as < 97.5. Results: Of the 58 pts analyzed, 26 presented with de novo MESCC, median age was 64 (range 48-85), 30 pts were ECOG PS ≤1 and 45% received systemic therapy. 93% of pts experienced weight loss > 5% in the 3 months preceding diagnosis and median BMI was 20.4 (range 16.3-34.9). Twenty-four (41%) pts were sarcopenic (SP) with differences in BMI and NRI (p < 0.05) compared to non-sarcopenic (NSP) pts. Median BMI in SP pts was 18.9 (16.3-25.6), 46% had a BMI < 18.5 and none were obese (BMI ≥ 30). By NRI, 58% of SP pts were malnourished. Males comprised 71% of SP pts (p = 0.03) but no difference from NSP MESCC pts was identified with age, race, ECOG PS or smoking status with univariate analysis. Median overall survival (OS) was 6 months; 4.2 in SP pts and 6.2 in NSP pts. Significant difference was identified with NRI (p = .0.009) but not sarcopenia (p = 0.247) or BMI (p = 0.393). With a multi-variate Cox model for NRI and sarcopenia, including age, sex, race, and ECOG PS, only ECOG PS was a significant predictor of mortality, HR for 2-3 vs 0-1 of 5.4 (2.5-11.9) p < 0.001. Conclusions: Sarcopenia at diagnosis was not associated with OS. NRI was superior to BMI alone with respect to discriminating pt outcomes, however ECOG PS was the only measure significantly associated with survival.

Impact of adjuvant therapy in patients with a microscopically positive margin after resection for gastroesophageal cancer

4069

Background: A microscopically positive (R1) resection margin following resection for gastroesophageal (GE) cancer has been documented to be a poor prognostic factor. The optimal strategy and impact of different modalities of adjuvant treatment for an R1 resection margin remain unclear. Methods: A retrospective analysis was performed for patients (pts) with GE cancer treated at the Princess Margaret Cancer Centre from 2006-2016. Electronic medical records of all pts with an R1 resection margin were reviewed. Kaplan-Meier and Cox proportional hazards methods were used to analyze recurrence free survival (RFS) and overall survival (OS) with stage and neoadjuvant treatment as covariates in the multivariate analysis. Results: We identified 78 GE cancer pts with an R1 resection. 11% had neoadjuvant chemotherapy, 14% chemoradiation (CRT), 75% surgery alone. 28% had involvement of the proximal margin, 13% distal, 56% radial, 3% had multiple positive margins. By the American Joint Committee on Cancer 7th edition classification, 88% had a pT3-4 tumour, 66% pN2-3 nodal involvement, 64% grade 3, 68% with lymphovascular invasion. 3% were pathological stage I, 21% stage II and 74% stage III. Adjuvant therapy was given in 46% of R1 pts (24% CRT, 18% chemotherapy alone, 3% radiation alone, 1% reoperation). Median RFS for all pts was 12.6 months (95% CI 10.3-17.2). Site of first recurrence was 71% distant, 16% locoregional, 13% mixed. Median OS was 29.3 months (95% CI 22.9-50) for all pts. The 5 year survival rate was 23% (95% CI 12%-43%). There was no significant difference in RFS (log-rank test p = 0.63, adjusted p = 0.14) or OS (log-rank test p = 0.68, adjusted p = 0.65) regardless of adjuvant therapy. Conclusions: Most pts with positive margins after resection for GE cancer had advanced pathologic stage and prognosis was poor. Our study did not find improved RFS or OS with adjuvant treatment and only one pt had reresection. The main failure pattern was distant recurrence, suggesting that pts being considered for adjuvant RT should be carefully selected. Further studies are required to determine factors to select pts with good prognosis despite a positive margin, or those who may benefit from adjuvant treatment.

Surveillance and outcomes after curative resection for gastroesophageal adenocarcinoma (GEAC)

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Background: Although commonly performed, evidence supporting routine surveillance testing (SvT) in patients (pts) with resected GEAC is lacking. We evaluated patterns of relapse, frequency of salvage therapy and outcomes among pts with resected GEAC who underwent surveillance. Methods: Between 2011 and 2016, 210 consecutive pts with GEAC followed at Princess Margaret Cancer Center after resection were reviewed. SvT was any investigation performed in the absence of pt-reported symptoms, abnormal physical exam findings, or bloodwork. Relapse patterns were classified as locoregional (LRR; surgical anastomosis/gastroesophageal lumen/regional nodes) or distant (DR; beyond locoregional). Time-to-relapse (TTR) and overall survival (OS) were calculated from initial diagnosis, post recurrence survival (PRS) from initial relapse. Results: Median age was 64.1 years. Esophageal (14%), gastroesophageal junction (40%), and gastric adenocarcinomas (45%) were treated with surgery alone (29%), surgery plus perioperative chemotherapy (26%) or surgery plus chemoradiation (45%). SvT included imaging (71%), endoscopy (19%), tumor markers (6%), and clinical visits alone (9%). After median follow-up of 38.3 months (mo) (range 5.6-122.3), 3- and 5-year OS rates were 68% (95% confidence interval (CI) 62-75%) and 56% (95% CI 49-64%) respectively. Among 97 relapses (46%), 51 were detected by SvT, 45 by symptoms. Relapse patterns included LRR alone (4%), DR alone (86%) and both (10%). The majority of relapses (93%) occurred within 3 years. Pts with SvT-detected relapse had similar median TTR (16.2 vs 13.3 mo, p = 0.40) but longer PRS (16.5 vs 4.6 mo, p < 0.001) and OS (36.2 vs 23.7 mo, p = 0.004) than pts with symptomatic relapse. Salvage therapy in 4 pts (2%) resulted in post recurrence disease-free survival ≥2 years. Duration of palliative chemotherapy was similar between 28 pts with SvT-detected relapse and 18 pts with symptomatic relapses (3.9 vs 3.3 mo, p = 0.64). Conclusions: Following curative resection, 96% of relapses were distant. Routine SvT rarely enabled successful salvage therapy and did not extend duration of palliative chemotherapy. Longer OS in SvT-detected relapses was not due to earlier disease detection. These findings do not support routine SvT in pts with resected GEAC.

Ramucirumab with cisplatin and fluoropyrimidine as first-line therapy in patients with metastatic gastric or junctional adenocarcinoma (RAINFALL): a double-blind, randomised, placebo-controlled, phase 3 trial

BACKGROUND

VEGF and VEGF receptor 2 (VEGFR-2)-mediated signalling and angiogenesis can contribute to the pathogenesis and progression of gastric cancer. We aimed to assess whether the addition of ramucirumab, a VEGFR-2 antagonist monoclonal antibody, to first-line chemotherapy improves outcomes in patients with metastatic gastric or gastro-oesophageal junction adenocarcinoma.

METHODS

For this double-blind, randomised, placebo-controlled, phase 3 trial done at 126 centres in 20 countries, we recruited patients aged 18 years or older with metastatic, HER2-negative gastric or gastro-oesophageal junction adenocarcinoma, an Eastern Cooperative Oncology Group (ECOG) performance status of 0 or 1, and adequate organ function. Eligible patients were randomly assigned (1:1) with an interactive web response system to receive cisplatin (80 mg/m2, on the first day) plus capecitabine (1000 mg/m2, twice daily for 14 days), every 21 days, and either ramucirumab (8 mg/kg) or placebo on days 1 and 8, every 21 days. 5-Fluorouracil (800 mg/m2 intravenous infusion on days 1-5) was permitted in patients unable to take capecitabine. The primary endpoint was investigator-assessed progression-free survival, analysed by intention to treat in the first 508 patients. We did a sensitivity analysis of the primary endpoint, including a central review of CT scans. Overall survival was a key secondary endpoint. This study is registered with ClinicalTrials.gov, number NCT02314117.

FINDINGS

Between Jan 28, 2015, and Sept 16, 2016, 645 patients were randomly assigned to receive ramucirumab plus fluoropyrimidine and cisplatin (n=326) or placebo plus fluoropyrimidine and cisplatin (n=319). Investigator-assessed progression-free survival was significantly longer in the ramucirumab group than the placebo group (hazard ratio [HR] 0·753, 95% CI 0·607-0·935, p=0·0106; median progression-free survival 5·7 months [5·5-6·5] vs 5·4 months [4·5-5·7]). A sensitivity analysis based on central independent review of the radiological images did not corroborate the investigator-assessed difference in progression-free survival (HR 0·961, 95% CI 0·768-1·203, p=0·74). There was no difference in overall survival between groups (0·962, 0·801-1·156, p=0·6757; median overall survival 11·2 months [9·9-11·9] in the ramucirumab group vs 10·7 months [9·5-11·9] in the placebo group). The most common grade 3-4 adverse events were neutropenia (85 [26%] of 323 patients in the ramucirumab group vs 85 [27%] of 315 in the placebo group), anaemia (39 [12%] vs 44 [14%]), and hypertension (32 [10%] vs 5 [2%]). The incidence of any-grade serious adverse events was 160 (50%) of 323 patients in the ramucirumab group and 149 (47%) of 315 patients in the placebo group. The most common serious adverse events were vomiting (14 [4%] in the ramucirumab group vs 21 [7%] in the placebo group) and diarrhoea (11 [3%] vs 19 [6%]). There were seven deaths in each group, either during study treatment or within 30 days of discontinuing study treatment, which were the result of treatment-related adverse events. In the ramucirumab group, these adverse events were acute kidney injury, cardiac arrest, gastric haemorrhage, peritonitis, pneumothorax, septic shock, and sudden death (n=1 of each). In the placebo group, these adverse events were cerebrovascular accident (n=1), multiple organ dysfunction syndrome (n=2), pulmonary embolism (n=2), sepsis (n=1), and small intestine perforation (n=1).

INTERPRETATION

Although the primary analysis for progression-free survival was statistically significant, this outcome was not confirmed in a sensitivity analysis of progression-free survival by central independent review, and did not improve overall survival. Therefore, the addition of ramucirumab to cisplatin plus fluoropyrimidine chemotherapy is not recommended as first-line treatment for this patient population.

FUNDING

Eli Lilly and Company.

Prognostic significance of malnutrition in metastatic esophageal squamous cell carcinoma

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Background: Disease related symptoms including anorexia, nausea and dysphagia lead patients with esophageal cancer to become malnourished. Malnourishment can result in systemic inflammation, reduced treatment tolerance, poorer quality of life and decreased overall survival. Currently weight loss is the main clinical measure of malnutrition, and thus we set out to evaluate the prognostic utility of alternative screening tools of malnutrition. Methods: Patients with metastatic esophageal squamous cell cancer (MESCC) attending the Princess Margaret Cancer Centre, between January 2011 and December 2016, were identified from the institutional gastroesophageal database. Nutritional Risk Score (NRS), Nutritional Risk Index (NRI) and Neutrophil Lymphocyte Ratio (NLR) were calculated and correlated with clinical-pathological variables and survival. Malnutrition was defined as NRS ≥ 3, NRI < 97.5 and NLR ≥ 3. Results: Of the 64 consecutive patients, 30 (47%) presented with de novo metastatic disease and 34 (53%) with recurrence. The median age was 62 years (range 40-85), 47 patients were ECOG PS ≤ 2 and 29 (45%) received systemic chemotherapy. 90% of patients experienced weight loss > 5% prior to diagnosis and median BMI was 20.1 (range 14.3-34.9). NRI identified 37 (58%) and NRS 45 (70%) patients as malnourished. Both were associated with poorer ECOG PS (p = 0.012 and p = 0.027 respectively). No difference was identified with sex, smoking status or albumin with univariate analysis. NRI did not associate significantly with age. Median overall survival was 5months; 8.1-9 months with normal nutrition and 2.8-3.2 months in malnourished patients. Kaplan Meier analysis revealed significant difference in overall survival (malnutrition vs. normal nutrition) using NRS (p = 0.029) and NRI (p = 0.001) but not weight (p = 0.509) or NLR (p = 0.69). Conclusions: Patients with MESCC identified as malnourished at the time of diagnosis have inferior survival outcomes. Malnutrition tools are superior to weight alone with respect to discriminating outcomes in this patient population. Further investigation is needed in larger patient cohorts; to identify those at risk, initiate early supportive interventions and improve patient outcomes.

Impact of adjuvant therapy in patients with a microscopically positive margin after resection for gastroesophageal cancer

164

Background: A microscopically positive (R1) resection margin following resection for gastroesophageal (GE) cancer has been documented to be a poor prognostic factor. The optimal strategy and impact of different modalities of adjuvant treatment for an R1 resection margin remain unclear. Methods: A retrospective analysis was performed for patients (pts) with GE cancer treated at the Princess Margaret Cancer Centre from 2006-2016. Electronic medical records of all pts with an R1 resection margin were reviewed. Kaplan-Meier and Cox proportional hazards methods were used to analyze recurrence free survival (RFS) and overall survival (OS) with stage and neoadjuvant treatment as covariates in the multivariate analysis. Results: We identified 78 GE cancer pts with an R1 resection. 11% had neoadjuvant chemotherapy, 14% chemoradiation (CRT), 75% surgery alone. 28% had involvement of the proximal margin, 13% distal, 56% radial, 3% had multiple positive margins. By the American Joint Committee on Cancer 7th edition classification, 88% had a pT3-4 tumour, 66% pN2-3 nodal involvement, 64% grade 3, 68% with lymphovascular invasion. 3% were pathological stage I, 21% stage II and 74% stage III. Adjuvant therapy was given in 46% of R1 pts (24% CRT, 18% chemotherapy alone, 3% radiation alone, 1% reoperation). Median RFS for all pts was 12.6 months (95% CI 10.3-17.2). Site of first recurrence was 71% distant, 16% locoregional, 13% mixed. Median OS was 29.3 months (95% CI 22.9-50) for all pts. The 5 year survival rate was 23% (95% CI 12%-43%). There was no significant difference in RFS (log-rank test p= 0.63, adjusted p= 0.14) or OS (log-rank test p= 0.68, adjusted p= 0.65) regardless of adjuvant therapy. Conclusions: Most pts with positive margins after resection for GE cancer had advanced pathologic stage and prognosis was poor. Our study did not find improved RFS or OS with adjuvant treatment and only one pt had reresection. The main failure pattern was distant recurrence, suggesting that pts being considered for adjuvant RT should be carefully selected. Further studies are required to determine factors to select pts with good prognosis despite a positive margin, or those who may benefit from adjuvant treatment.

An updated retrospective review of the safety and efficacy of sorafenib for recurrent hepatocellular carcinoma post-liver transplantation

313

Background: Orthotopic liver transplantation (OLT) is a potentially curative treatment for hepatocellular carcinoma (HCC). Despite an estimated recurrence rate between 15%-20%, there is currently no proven systemic therapy for the treatment of HCC relapse post OLT. Sorafenib has been a standard therapy for advanced HCC however data is lacking for the safety and efficacy of sorafenib in the setting of concurrent immunosuppressive agents. Methods: A retrospective review was performed of patients who received sorafenib for HCC relapse after OLT. Data on patient characteristics, treatment toxicity and efficacy was collected. The primary objectives were to evaluate toxicity and safety of sorafenib when used in combination with immunosuppressive therapies such as calcineurin and mTOR inhibitors. Secondary objectives were objective response rate, progression free survival (PFS), and time on therapy. Results: 35 patients over the last 11 years received sorafenib for HCC recurrence following OLT. 54.3% of patients received concurrent immunosuppression with tacrolimus. Toxicity from sorafenib was as expected, with no cases of acute or chronic organ rejection whilst on treatment. The median maximum tolerated dose was 400 mg a day with 40% of patients requiring dose reductions. The incidence of any adverse events (AEs) was 88.6%, with 17.1% having Grade 3-4 toxicity. Incidence of Grade 3-4 liver dysfunction was higher than historical studies at 6%. The overall response rate was 2.8% with a median PFS of 2.8 months. Median time on sorafenib was 3.1 months. Conclusions: There is a paucity of evidence guiding treatment of HCC recurrence following OLT. This retrospective review is one of the largest in the literature and shows that sorafenib used concurrently with immunosuppressive therapy for organ transplant is safe, with no precipitation of acute or chronic rejection, although liver function should be monitored closely. The median PFS in our cohort was shorter than expected. The efficacy of other agents should be explored in this population.[Table: see text]

Surveillance and outcomes after curative resection for gastroesophageal adenocarcinoma (GEAC)

162

Background: Although commonly performed, the benefit of routine surveillance testing (SvT) following curative resection of GEAC is undefined. We aimed to determine frequency of successful salvage therapy (SST) in patients (pts) with relapsed GEAC who were surveyed post curative therapy. Methods: Between 2011 and 2016, 210 consecutive pts with locally advanced GEAC underwent curative surgery and subsequent surveillance at Princess Margaret Cancer Center. SST was defined as any potentially curative therapy for recurrence which resulted in post-recurrence survival (PRS) two years without further relapse. Time-to-event outcomes were analyzed using Kaplan-Meier and Cox regression methods. Results: Median age was 64.1 years. Esophageal (14%), gastroesophageal junction (41%), and gastric adenocarcinomas (45%) were included. Pts received surgery alone (29%), surgery with perioperative chemotherapy (26%) or perioperative chemoradiation (45%) as primary curative therapy. At median follow-up of 33.6 months (m, range 6.0-122.4), 3- and 5-year overall survival (OS) rates were 68% (95% CI 61-75%) and 59% (95% CI 51-68%) respectively. SvT modalities included imaging (69%), endoscopy (19%), tumor markers (4%), and clinical visits only (9%). Recurrences occurred in 95 (45%) pts, 51% were surveillance-detected (SvDR), and 47% were non-SvDR. Types of recurrences included locoregional only (4%), distant (87%) or both (9%). Salvage therapy was attempted in 14 pts (7%) with SvDR and 1 with non-SvDR. In four pts with SvDR (1.9%) salvage therapy was successful with chemoradiation or surgery perioperative chemotherapy, six were unsuccessful, and 5 had immature follow-up. Compared with pts with non-SvDR, pts with SvDR had longer median OS (34.8 vs. 24.0m, p=0.03) and PRS (14.4 vs. 4.8m, p < 0.001), and similar time-to-relapse (15.6 vs. 12.0m, p = 0.67). Palliative chemotherapy was administered in 25 pts with SvDR and 18 pts with non-SvDR with similar median duration (3.5m vs. 3.3m, p=0.64). Conclusions: Following curative therapy, 96% of relapses were distant. SvT enabled SST in only 1.9% of pts, and did not extend duration of palliative chemotherapy. These data do not support the use of routine SvT in resected GEAC.

Survival outcomes for de novo versus relapsed stage IV gastric and gastroesophageal junction (GEJ) adenocarcinoma

148

Background: In gastric/GEJ cancer, 40% of patients (pts) are metastatic at diagnosis ( de novo stage IV) and up to 70% with locoregional disease recur (relapsed stage IV). We compared survival outcomes between de novo vs relapsed stage IV. Methods: A retrospective observational study of stage IV gastric/GEJ pts was conducted (2012-2015). Overall survival (OS) was from date of stage IV diagnosis. PFS1 defined the period from stage IV diagnosis to first progression. PFS2 was from first to second progression. For relapsed stage IV pts, disease-free interval (DFI) was the period from initial diagnosis to metastatic relapse. Cox proportional hazards models compared OS, PFS1 and PFS2 between de novo vs relapsed stage IV pts, stratified by DFI [ < 6, 6-12 and > 12 months (mo)] and controlled for baseline patient characteristics. Results: Of 198 pts, 62% were male and median age was 64 years (26-93), with 64% gastric and 36% GEJ adenocarcinomas. Primary therapy for locoregional pts included surgery (75%), perioperative chemotherapy (42%) and radiotherapy (42%). De novo and relapsed stage IV pts represented 68% and 32% of the cohort respectively. Median follow-up was 13 mo. Controlled for age, performance status and Charlson comorbidity index, there were no significant differences in OS (median OS 12.5 ( de novo) vs 12.2 mo (relapsed); HR 1.22, 95% CI 0.83-1.77, p = 0.31), PFS1 (6.8 vs 7.4 mo; HR 1.00, 95% CI 0.65-1.56, p = 0.98) or PFS2 (3.8 vs 3.0 mo; HR 1.03, 95% CI 0.44-2.41, p = 0.95). Median OS for relapsed stage IV patients were different by DFI groups (log-rank p = 0.02): 22.9 mo (for DFI > 12mo; n = 31), 11.2 mo (DFI 6-12; n = 19) and 7.5 mo (DFI < 6; n = 14). Additionally, OS was significantly better if the DFI was greater than 12 mo, compared with de novo stage IV (HR 0.50, 95% CI 0.28-0.88, p = 0.02). Conclusions: There was no observed difference in the natural history of de novo vs relapsed stage IV gastric/GEJ pts. DFI was strongly prognostic with median OS (from date of relapse) approaching 2 years for relapsed pts with DFI > 12 mo. In addition to implications for treatment strategy, tumor biology within subgroups should be examined to identify novel biomarkers and potential therapeutic targets.

Screening for cancer-associated dysphagia: The development of two rapid tools for use in observational studies and routine care

164

Background: Dysphagia as a cancer symptom can be associated with significant morbidity. We developed dysphagia screener tools for use in observational studies (Phase 1) and routine symptom monitoring in clinical care (Phase 2). Methods: Various dysphagia or odynophagia screening questions, selected after an expert panel reviewed content, criterion, and construct validity, were compared to either FACT-E Swallowing Index Cut-Off Values (SICV) or to questions adapted from the Patient Reported Outcomes for Common Terminology Criteria for Adverse Events (PRO-CTCAE). Sensitivity, specificity and patient acceptability were assessed. Results: In developing a tool for observational studies (Phase 1; n = 178 esophageal cancer patients), the screening question, “How are you currently eating?” had the highest sensitivities and specificities against various SICV cut-offs, with the best optimal cut-off associated with the clinical outcome of weight loss (80% sensitivity, 75% specificity). When developing a rapid screening tool for routine symptom monitoring (Phase 2; 255 head and neck, gastro-esophageal, and patients undergoing thoracic radiation), a single question screener (“Do you experience any difficulty or pain upon swallowing?”) versus a PRO-CTCAE-like gold standard generated sensitivities between 86-94% and specificities between 93-100%. The screening question (+/- follow-up questions where indicated) had a median completion time of under 2 minutes, and > 90% of patients were happy to complete the survey on an electronic tablet, did not feel that survey completion made their clinic visit more difficult, and did not find the questions upsetting or distressful. Conclusions: Two screener tools (for prospective observational studies “How are you currently eating?”, and for routine clinical monitoring “Do you experience any difficulty or pain upon swallowing?”) can effectively screen dysphagia symptoms without increasing cancer outpatient clinic burden.

Management of metastatic gastric and esophageal cancer in older adults

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Background: Older adults are under-represented or excluded from pivotal trials of palliative chemotherapy for metastatic gastric and esophageal (GE) cancers. Little is known about how older patients are treated in the real world. The objective of this study was to examine the impact of age on treatment and survival. Methods: Patients aged ≥65 years were identified from a retrospective database of patients with metastatic GE cancer (Princess Margaret Cancer Centre; 2011-2016). The impact of age ≥75 years (old-old) versus (vs.) 65-74 years (young-old) on treatment and survival was assessed using multivariable logistic and Cox proportional hazard regression models, respectively, adjusted for known prognostic factors including sex, comorbidity, primary site, histology, grade, stage at initial diagnosis, metastatic sites, and chemotherapy use. Results: Of 183 patients, median age was 72 (range 65-92) years; 31% were old-old. Old-old patients were less likely to be treated with any chemotherapy (12.3% vs. 45.2% young-old; adjusted odds ratio = 0.12 (95% confidence interval (CI) 0.05-0.31)). With a median follow-up of 5.7 months, 135 (74%) had died during follow-up; median overall survival (OS) was 5.2 months (mo) for the old-old vs. 8.4 mo (young-old). There was no significant difference in survival between the two groups after adjustment for known prognostic factors (old-old vs. young-old: univariable hazard ratio (HR) 1.75 (95% CI 1.2-2.5); adjusted HR 1.1 (95% CI 0.7-1.7). Treatment with any chemotherapy was associated with an improvement in survival: adjusted HR 0.34 (95%CI 0.22-0.52). Conclusions: In this single-centre study of older adults with metastatic GE cancer, there was an overall low rate of treatment with chemotherapy; those ≥75 were rarely treated. After accounting for known prognostic factors, there was no observed difference in survival between patients ≥75 and those 65 to 74. Comprehensive geriatric assessment may improve treatment selection in the older population. [Table: see text]

Outcomes for advanced HER2-positive gastroesophageal cancer by anatomical location: Experience from the Princess Margaret Cancer Centre

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Background: The landmark ToGA trial established trastuzumab (T) based therapy as the standard of care for advanced HER2+ gastric and gastroesophageal junction cancer. However, outcomes for T based therapy for HER2+ esophageal cancer have not been well characterized. Methods: We conducted a retrospective analysis of patients (pts) with HER2+ gastroesophageal cancer receiving T based therapy at our institution from 2011-2016. Distal esophagus ( < 35 cm) and Siewert type I/II tumours were defined as esophageal (E). Siewert type III and stomach tumours were defined as gastric (G). Trained abstractors collected pt demographics and treatment details. Overall survival (OS) and progression-free survival (PFS) were calculated from the date of first T treatment. Chi-square tests, t-tests and Cox proportional hazards models were applied where appropriate. Results: We identified 87 pts with advanced HER2+ disease. 62% (n = 54) had de novo metastatic (M1) disease. 57 patients were treated with T based therapy, with median age 57 years (IQR 48-67), 91% baseline performance status 0-1, 19% female, and 7% Asian. 63% (n = 36) had E and 37% (n = 21) had G primary tumours. 67% (n = 38) presented with M1 disease. 33% (n = 19) underwent surgery with curative intent and received T based therapy at recurrence. Baseline characteristics were balanced between the E and G groups. Survival data were available for 51 patients. The E and G groups did not have significant differences in PFS (median 9.5 vs. 9.1 months, HR 0.89 (95% CI 0.44-1.80), p = 0.74) or in OS (median 15.8 vs. 14.2 months, HR 0.88 (95% CI 0.42-1.82), p = 0.73). 63% (n = 36) were treated with subsequent systemic therapy after progression on T, with 23 receiving one line, 9 receiving two lines and 4 receiving three additional lines of treatment. The number subsequent therapies received was similar between E and G groups. Conclusions: Although patients with distal esophagus tumours were not included in the ToGA trial, our analysis suggests that patients with E and G tumours had similar outcomes. Our contemporary cohort had comparable survival outcomes relative to patients receiving T in the ToGA trial (median PFS = 6.7 months, median OS = 13.8 months).

Relationship between human epidermal growth factor receptor 2 (HER2) status and central nervous system metastases in gastroesophageal cancer

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Background: Central nervous system (CNS) metastases (mets) in gastroesophageal (GE) cancers are rare. There have only been limited studies examining the role of HER2 status in CNS mets in GE cancers. Methods: A retrospective analysis was performed for patients (pts) treated for GE cancers at the Princess Margaret Cancer Centre from 2011-2016. Quantitative and qualitative data were collected for all pts with CNS mets. Kaplan-Meier method was used to calculate overall survival (OS) and CNS progression free survival (PFS) for CNS mets pts. Results: Of 34 GE cancer pts diagnosed with CNS mets, 11 were HER2+, 11 HER2- and 12 had unknown HER2 status. Median time from initial cancer diagnosis to CNS mets was 10.3 months (13.4 in HER2+, 5.8 in HER2-, 11.7 in HER2 unknown). Characteristics at CNS mets diagnosis included: median age 63; 85% male; 74% had extracranial systemic mets; performance status ECOG 0-1 (64%), 2 (12%), 3-4 (24%). Treatment for CNS mets is shown in Table 1. Median OS from diagnosis of CNS mets was 6.1 months (95%CI 3.2-16.4) for all pts, 17.1 (95%CI 9.9-NA) in HER2+, 1.8 (95%CI 0.6-NA) in HER2-, 6.0 (95%CI 1.9-NA) in HER2 unknown, p=0.01. Median OS from initial cancer diagnosis was 18.5 months (95%CI 13.6-33.7) for all pts, 28.9 (95%CI 21.32-NA) in HER2+, 10.8 (95%CI 6.37-NA) in HER2-, 18.6 (95%CI 10-NA) in HER2 unknown, p=0.015. The 1 year CNS PFS rate was 35% (95%CI 22.1 – 55.5%) for all pts, 53% (95%CI 29.9 – 94%) in HER2+, 18.2% (95%CI 5.3 – 63.7%) in HER2-, 33% (95%CI 15 – 74.2%) in HER2 unknown, p=0.053. Conclusions: HER2+ pts tended to develop CNS mets later than HER2-. HER2+ pts were more likely to receive CNS-directed interventions, with more HER2+ pts having surgery for CNS mets while more HER2- had supportive care. This analysis is the first to suggest that in pts with CNS mets, HER2+ pts had longer survival than HER2-, both from initial diagnosis and after developing CNS metastases.[Table: see text]

Tumor platinum concentrations and pathological responses following preoperative cisplatin-containing chemotherapy in gastric or gastroesophageal junction cancer patients

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Background: Perioperative chemotherapy plus surgical resection is a standard of care for locally advanced gastric or gastroesophageal junction (GEJ) cancers. There is a wide range in tumor response following cisplatin-containing preoperative chemotherapy. We investigated the relationship between tumor platinum levels and pathological tumor responses in gastric or GEJ cancer patients following preoperative chemotherapy. Methods: Tumor and adjacent normal tissues were retrieved. Pathological responses were assessed per standard criteria. Tissue platinum concentrations were determined with high-performance liquid chromatography mass spectrometry. Platinum distribution in tissue components was evaluated with imaging mass cytometry. Tissue collagen content was evaluated using trichrome staining. Results: Ten patients were enrolled in this study. Nine patients received 3 cycles of preoperative chemotherapy and 1 received 2 cycles. The median cumulative cisplatin dose was 166.8 mg/m2 (range: 95.9–181.1 mg/m2). Surgery was performed at a median time of 49 days (range: 28–72 days) after the last cycle of chemotherapy. The mean platinum level in tumor tissue in patients with any response was 893 ± 460 pg, significantly higher than in those with no response [38.8 ± 8.8 pg (p = 0.007)]. The collagen content was significantly higher in patients with any response than in those with no response (37.4 ± 6.8% vs. 11.5 ± 8.6%, p < 0.05). Platinum preferentially bound to collagen. Conclusions: Platinum was detectable in surgical specimens up to 72 days after preoperative chemotherapy. Higher tumor platinum concentration correlated with improved pathological response. Collagen binding potentially explained the high interpatient variability in tumor platinum concentrations.

Baseline anemia in patients with biliary tract cancer (BTC) and its association with survival: A retrospective cohort study

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Background: The prognostic significance of anemia in BTC is unknown, but is common and may be multifactorial; data regarding its causes are limited. This study interrogated a large institutional database to examine the effect of anemia on overall survival (OS) in BTC, and explore factors associated with anemia. Methods: This Princess Margaret Cancer Centre cohort study included patients with BTC with available baseline hemoglobin (Hb) (1987-2016). Anemia was defined as Hb < 132 mg/dL for men > 60 years, < 137mg/dL for men aged 20-59, and < 122mg/dL in women. Additional relevant covariates were included in multivariable Cox regression for OS, and linear regression for association with Hb. Results: Of 1398 patients included, 711 (51%) were anemic at baseline (mean Hb 112 mg/dL). Anemic versus non-anemic patients were older (median age 66 vs 64 yrs, p = 0.006), had worse ECOG PS (12% ECOG 2-3 vs 6%, p < .001), BMI < 20 (31% vs 27%, p = 0.006) and elevated neutrophil:lymphocyte ratio (NLR), (64% vs 47%, p < .001), but cancer staging was not significantly different. Anemia was associated with shorter OS on univariate (HR 1.35, p < .001) and multivariable (HR 1.39, p < .001) regression (Table). Factors associated with lower Hb included older age, male gender, worse ECOG PS, tumor site, thrombocytopenia, elevated NLR. Conclusions: Baseline anemia was associated with shorter survival following diagnosis of BTC, independent of tumor stage or ECOG PS. Clinicians should be aware of this prognostic marker; validation in prospective datasets is warranted. [Table: see text]

KEYNOTE-059 cohort 1: Pembrolizumab (Pembro) monotherapy in previously treated advanced gastric or gastroesophageal junction (G/GEJ) cancer in patients (Pts) with PD-L1+ tumors—Asian subgroup analysis

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Background: The US FDA approved pembro for treating pts with 1) recurrent locally advanced or metastatic G/GEJ adenocarcinoma, whose disease has progressed on or after ≥2 prior therapies and whose tumors express PD-L1 (combined positive score [CPS] ≥1), and 2) unresectable or metastatic, microsatellite instability-high (MSI-H) solid tumors that have progressed after prior therapy and who have no fitting options. We report Asian subgroup analyses from cohort 1 of KEYNOTE-059 (NCT02335411), a global, phase 2 study in advanced G/GEJ cancer. Methods: Eligible pts had measurable recurrent or metastatic G/GEJ adenocarcinoma whose disease has progressed on ≥2 prior chemotherapy regimens. Pts received pembro 200 mg Q3W up to 2 y. PD-L1+ tumors had a CPS ≥1. Primary end points were ORR (RECIST 1.1, by central review) and safety. Results: Cohort 1 enrolled 259 pts; 57% had PD-L1+ tumors. MSI status was evaluable in 174 tumor samples; of these, 7 were MSI-H. At data cutoff (4/21/2017), median (range) follow-up was 6 mo (1-25). Overall ORR was 12% (95% CI, 8-17) and median (range) DOR was 14 mo (2-19+). PFS6-mo rate was 15% and OS6-mo rate was 46%. In pts with PD-L1+ tumors, ORR was 16% (95% CI, 11-23) and median (range) DOR was 14 mo (3+-19+). In pts with PD-L1+ tumors, PFS6-mo rate was 20% and OS6-mo rate was 50%. In pts with MSI-H tumors, ORR was 57% (95% CI, 18-90) and median (range) DOR was not reached (5-14+ mo). In cohort 1, 41 pts were Asian and 218 pts were non-Asian. PD-L1+ tumors occurred in 42% of Asian pts and 60% of non-Asian pts. ORR was 12% (95% CI, 2-36) in Asian pts with PD-L1+ tumors and 17% (95% CI, 11-24) in non-Asian pts with PD-L1+ tumors. One of 7 pts with MSI-H tumors was Asian; this pt had CR. Grade 3-5 treatment-related AEs occurred in 17% and 18% of Asian and non-Asian pts, similar to the overall cohort. Conclusions: Pembro showed durable clinical benefit in previously treated pts with advanced G/GEJ cancer, especially those with PD-L1+ or MSI-H tumors. Safety and efficacy were similar in Asian and non-Asian pts. These findings highlight pembro as a standard treatment option in Asian and non-Asian pts with advanced G/GEJ cancer. Clinical trial information: NCT02335411.

Comparison of bimodality versus trimodality therapy for esophageal or gastroesophageal junction (GEJ) cancer: Experience from the Princess Margaret Cancer Centre

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Background: There are no phase 3 trials comparing definitive chemoradiation (bimodality) versus. perioperative chemoradiation (trimodality) for locoregional esophageal/GEJ cancer. Methods: A retrospective analysis (2011-2015) compared bimodality and trimodality therapy in patients (pts) with locoregional esophageal/GEJ cancer treated with curative intent. Overall survival (OS) and disease-free survival (DFS) were calculated from the date of diagnosis. Uni- and multivariable Cox proportional hazards regression adjusted for patient and disease factors. Results: Of 108 patients, 82 (76%) were male. Mean ages were 69.5 ± 11.0 years (bimodality; N = 41) and 60.5 ± 11.1 years (trimodality; N = 67). For bimodality pts, 37% had adenocarcinoma and 63% had squamous cell carcinoma (SCC). For trimodality pts, 79% had adenocarcinoma and 21% had SCC (p < 0.0001). Bimodality pts received a higher radiation dose compared to trimodality pts (50.1 ± 6.7 vs. 45.2 ± 6.4 Gy). Median follow-up was 49.3 months. We found no significant OS difference between bimodality (27.0 months) and trimodality therapy (29.8 months) in the overall cohort (p = 0.57) (4 year OS rate: 42% vs. 38%). In the subgroup with adenocarcinoma histology, trimodality therapy significantly improved OS and DFS compared to bimodality (OS: 31.8 vs. 10.4 months, hazard ratio (HR) 0.34, 95% confidence interval (CI) 0.18-0.66, p = 0.001; DFS: 15.0 vs. 6.7 months; HR 0.39, 95%CI 0.21-0.73, p = 0.003). In the SCC subgroup, median OS and DFS were similar (OS: not reached vs. 29.2 months, p = 0.48; DFS: 27.0 vs. 24.0, p = 0.96). Using multivariable regression with AIC backward selection, the only retained prognostic factors were treatment modality (p = 0.06) and histology (p = 0.01). Conclusions: Our findings support preferential use of trimodality therapy for pts with adenocarcinoma histology given superior OS and DFS, whereas bimodality and trimodality therapy appeared comparable in pts with SCC histology. Pending confirmation in a larger series with longer follow-up, these findings suggest differential treatment algorithms for locoregional esophageal and GEJ cancer based on tumor histology.

Patterns of recurrence and outcomes after curative resection of locally advanced HER2-positive gastroesophageal cancer (HPGEC)

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Background: Literature on recurrence and outcomes of HPGEC is scarce. The aim of this study was to determine pattern of recurrence and outcomes after curative intent surgery for locally advanced HPGEC. Methods: A retrospective database was used to identify consecutive patients with gastroesophageal adenocarcinomas undergoing curative intent resection between 2011 and 2016 at the Princess Margaret Cancer Centre. Clinico-demographic data were extracted from the electronic health record. Patterns of relapse are classified as nonvisceral (defined as recurrences in the bone, peritoneal or both), visceral (not nonvisceral, including the brain), or both. Time to relapse (TTR) and overall survival (OS) were calculated from date of histologic diagnosis. Results: Of 45 patients with HPGEC, 78% were male, and 91% were non-Asian. Median age was 64.4 years (interquartile range [IQR] 53, 70); 60% were gastroesophageal junction, 24% were gastric, and 16% were esophageal adenocarcinomas; 31% were poorly differentiated tumors while 68% had clinical or pathological node positive disease. Complete R0 resection occurred in 93%, and 84% had received perioperative therapy (31% with perioperative chemotherapy; 40% with pre-operative chemoradiation; 9% with post-operative chemoradiation). With a median follow-up time of 26.0 months. relapse rate of HPGEC at last follow-up was 78%. Among first relapses, 94% were distant, while 6% were local recurrences. Among distant relapses, visceral recurrences occurred in 85%, nonvisceral in 3%, and 12% patients had both visceral and nonvisceral recurrences. None had peritoneal only recurrence. Median TTR was 12.2 months (IQR 8.8, 23.5), while median post-recurrence survival was 9.7 months (IQR 4.7, 16.3). Of the entire cohort, 2-year OS was 53% and 3-year OS was 26%. Conclusions: More than three-quarters of patients with HPGEC experienced recurrence after curative intent multimodality therapy. Our results suggest that HPGEC rarely relapse with peritoneal only disease or local recurrence, thereby calling into question the utility for aggressive surveillance, pending verification from larger cohorts.

Comparison of chemoradiotherapy (CRT) using carboplatin/paclitaxel (CP) versus cisplatin/5-FU (CF) for esophageal or gastroesophageal junctional (GEJ) cancer

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Background: For resectable esophageal or GEJ cancer, trimodality therapy improves survival compared to surgery alone and represents the current standard of care. The optimal CRT regimen for neoadjuvant or definitive treatment of locoregional esophageal or GEJ cancer remains uncertain. Methods: A retrospective comparison of CF and CP for locoregional esophageal or GEJ cancer (2011-2015) was performed. Overall survival (OS) and disease-free survival (DFS) were assessed using multivariable Cox proportional hazards regression, controlling for age, performance status and Charlson comorbidity index. Results: 101 patients (pts) were identified (61 CF, 40 CP). 75% were male. Median age was 62 years (range 30-84). Primary sites were esophageal (52%, with 65% squamous histology) and GEJ (48%). Surgery was undertaken in 34 (56%) CF and 27 (68%) CP pts. Median follow-up was 43 months. Overall, there was a non-significant trend for improved OS with CF compared to CP (HR 0.61, 95% CI 0.33-1.14, p = 0.12). In the subgroup having surgery (N = 61), we found no significant difference in OS (HR 0.99, 95% CI 0.39-2.55, p = 0.99). In the subgroup without surgery (N = 40), CF was significantly superior to CP (HR 0.21, 95% CI 0.08-0.53, p < 0.001). Comparing only pts in this subgroup who received equitable radiation doses (N = 33), CF was still significantly superior to CP (HR 0.09, 95% CI 0.03-0.32, p < 0.001). OS was similar by histology (adenocarcinoma/squamous) in all-comers (p = 0.54), and in CF (p = 0.90) and CP subgroups (p = 0.63). DFS results corresponded with OS. There was a non-significant numerical difference in pCR rates between CF (31%) and CP (18%) (p = 0.35), which were lower than previously reported. Conclusions: Survival is similar for CF and CP CRT regimens in pts undergoing trimodality therapy, but for those who do not proceed to surgery, it appears that CF is more effective than CP. Clinicians may prefer CP for surgical candidates given its favourable toxicity profile. However, when treating with definitive CRT, CF may be preferable to CP as a standard regimen.

Outcomes for patients ≥75 years with localized gastroesophageal cancer: Experience from the Princess Margaret Cancer Centre

10037

Background: The optimal treatment and outcome for elderly patients (pts) with localized gastroesophageal (GE) cancer remains unclear as they are underrepresented in clinical trials. We aimed to assess survival in pts ≥75 years according to treatment received. Methods: A retrospective analysis was performed for all pts aged ≥75 years with GE cancer treated in 2012-2014. Frailty was measured using the Charlson comorbidity index (CCI) and ECOG performance status (PS). Overall survival (OS) and disease-free survival (DFS) were assessed via uni- and multivariable Cox proportional hazards regression, adjusting for demographics. Logistic regression analyses were used to examine factors impacting treatment choices. Results: Of 105 pts, median age was 81 years (range: 75-99), primary sites were esophageal (55%, with 43% squamous histology) and gastric (45%). Baseline characteristics included: PS: 0 (31%), 1 (42%), 2 (16%), 3 (10%), 4 (1%); and CCI: 0 (34%), 1 (25%), 2 (19%), ≥3 (22%). Treatment received included radiotherapy alone (RT) (31%); surgery alone (29%); surgery plus adjuvant chemotherapy (chemo) and/or RT (14%); chemoradiation alone (7%) and supportive care (18%). In univariable analyses; age < 85 (p = 0.003), PS < 2 (p = 0.03) and surgery (p < 0.001) were associated with improved OS. Chemo and RT, either alone or in combination, did not significantly improve OS. In multivariable analyses; surgery (HR 0.38, 95% CI 0.21-0.70, p = 0.002) was the only independent predictor for improved OS. Patients with good PS (p = 0.01), gastric disease site (p = 0.01) and adenocarcinoma histology (p = 0.02) were more likely to undergo surgery. Conclusions: At our institution, relatively few pts ≥75 years received multimodality therapy for localized GE cancers. Those pts ≥75 years who underwent surgery had excellent outcomes, but they were well-selected. Comprehensive assessment should be considered for pts ≥75 years with localized GE cancer to ensure optimal treatment selection, particularly given the potential benefit of surgery.

KEYNOTE-059 cohort 1: Efficacy and safety of pembrolizumab (pembro) monotherapy in patients with previously treated advanced gastric cancer

4003

Background: Pembro has shown promising antitumor activity and manageable safety in a phase 1 study of pts with previously treated advanced gastric cancer. We conducted a global, multicohort, phase 2 study of pembro in pts with advanced gastric or gastroesophageal junction (G/GEJ) cancer (KEYNOTE-059;NCT02335411). Methods: Cohort 1 enrolled 259 pts, aged ≥18 y with measurable recurrent or metastatic G/GEJ adenocarcinoma who had progressed on ≥2 prior chemotherapy regimens and had ECOG PS 0-1. Pts received pembro 200 mg Q3W up to 2 y or up to disease progression, investigator/pt decision to withdrawal, or unacceptable toxicity. PD-L1+pts had expression in ≥1% tumor or stromal cells using IHC (22C3 antibody). Primary end points: ORR (RECIST 1.1, by central review), safety, and tolerability. Results: Of 259 pts in cohort 1, 76.4% were men; median age was 62.0 y. 51.7% and 48.3% received pembro as 3rd-line (3L) and 4L+ therapy, respectively. 57.1% had PD-L1+ tumors. At data cutoff (Oct 19, 2016), median duration of follow-up was 5.4 mo (range, 0.5 to 18.7). Overall ORR (CR + PR) was 11.2% (95% CI, 7.6-15.7); 1.9% of pts (95% CI, 0.6-4.4) had CR, 9.3% had PR (95% CI, 6.0-13.5), 17% (95% CI, 12.6-22.1) had SD, and 55.6% (95% CI, 49.3-61.7) had PD. Median DOR was 8.1 mo (range, 1.4+ to 15.1+). ORR was 14.9% (95% CI, 9.4-22.1) in 3L pts and 7.2% (95% CI, 3.3-13.2) in 4L+. In PD-L1+ pts, ORR was 15.5% (95% CI, 10.1-22.4) with 2.0% (95% CI, 0.4-5.8) CR and 13.5% (95% CI, 8.5-20.1) PR; in PD-L1– pts, ORR was 5.5% (95% CI, 2.0-11.6), with 1.8% (95% CI, 0.2-6.5) CR and 3.7% (95% CI, 1.0-9.1) PR. In 3L pts with PD-L1+ tumors, ORR was 21.3% (95% CI, 12.7-32.3), with 4.0% (95% CI, 0.8-11.2) CR; in 3L pts with PD-L1– tumors, ORR was 6.9% (95% CI, 1.9-16.7), with 3.4% (95% CI, 0.4-11.9) CR. Grade 3-5 treatment-related AEs (TRAEs) occurred in 43 pts (16.6%). TRAEs led to discontinuation in 2 pts (abnormal LFT, bile duct stenosis) and were fatal in 2 pts (acute kidney injury, pleural effusion). Conclusions: Pembro showed encouraging efficacy and manageable safety after ≥2 prior lines of therapy in pts with advanced G/GEJ cancer in this large phase 2 trial. Survival and additional biomarker data, including MSI status, will be presented. Clinical trial information: NCT02335411.

Sorafenib treatment in recurrent hepatocellular carcinoma post liver transplantation

e15613

Background: Liver transplantation (LT) is a potentially curative treatment for patients (pts) with selective hepatocellular carcinoma (HCC). HCC recurrence post LT is estimated to be 15-20%. Data on systemic therapy post-recurrence is scarce and limited case series suggest that sorafenib (SOR) may have benefit in this population. We reviewed a single center experience with SOR in recurrent HCC post LT Methods: A retrospective review was conducted on pts with recurrent HCC post LT at University Health Network (UHN) who were treated with SOR. Pt characteristics were collected including age, gender, comorbidities, background liver disease, type of LT, and time to recurrence after LT. Treatment information collected included: initial SOR dose (and adjustments), adverse events (AEs), duration of treatment and survival. Results: Between 2006 and 2016, 24 pts were identified. The average age was 60 years (range: 18-72), most pts were male (20/4), living/cadaveric transplant: 11/13. HCC etiology included hepatitis B (10), alcohol (4), NASH (3), hepatitis C (2), hemochromatosis (2), Budd-Chiari (2) and unknown (1). The average time to recurrence of HCC was 16.08 (range: 1.5-60) months post OLT. There was a bimodal time to recurrence with a median of 6 months. SOR starting doses were 200 mg BID in 18 pts, 300 mg BID in 1 and 400 mg BID in 4. 14 pts required dose adjustment due to AEs, mainly relating to fatigue and palmar-plantar syndrome. The median time on treatment was 2.5 (range: 0.25-37) months. The average time to progression on SOR and/or discontinuation due to AEs was 4.30 (+/- 7.2) months. Conclusions: SOR is reasonably tolerated in pts with recurrent HCC post LT, with expected AE profiles. In this small case series, the median time on SOR was short and estimated time to progression was shorter than that in non-transplant HCC population. Overall, SOR has limited activity in this population, but selected pts may derive extended benefit. Better understanding of responders and investigations of other therapies are needed for this population.

Outcomes for patients ≥75 years with localized gastroesophageal cancer: Experience from the Princess Margaret Cancer Centre

189

Background: The optimal treatment and outcome for elderly patients (pts) with localized gastroesophageal (GE) cancer remains unclear as they are underrepresented in clinical trials. We aimed to assess survival in pts ≥ 75 years according to treatment received. Methods: A retrospective analysis was performed for all pts aged ≥ 75 years with GE cancer treated in 2012 and 2013. Frailty was measured using the Charlson comorbidity index (CCI) and ECOG performance status (PS). Overall survival (OS) and disease-free survival (DFS) were assessed via uni- and multivariable Cox proportional hazards regression, adjusting for demographics. Logistic regression analyses were used to examine factors impacting treatment choices. Results: Of 70 pts, median age was 82 years (range: 75-98), primary sites were esophageal (40%, with 61% squamous histology), GE junction (24%) and gastric (36%). Baseline characteristics included: PS: 0 (40%), 1 (39%), 2 (14%), 3 (7%); and CCI: 0 (36%), 1 (20%), 2 (21%), ≥ 3 (23%). Treatment received included surgery (33%), radiotherapy (RT) (31%); surgery plus adjuvant chemotherapy (chemo) and/or RT (9%); chemoradiation alone (7%) and 20% had no active treatment. In univariable analysis; age < 85 (p = 0.007) and surgery (p = 0.022) were associated with improved OS. Chemo and RT, either alone or in combination, did not significantly improve OS. In multivariable analysis; age < 85 (HR 0.46, 95% CI: 0.23-0.94, p = 0.034), surgery (HR 0.32, 95% CI: 0.14-0.74, p = 0.008) and CCI < 2 (HR 0.52, 95% CI: 0.27-0.99, p = 0.048) were identified as independent predictors for improved OS. Age ≥ 85 was significantly associated with omission of surgery (OR 3.61, 95% CI: 1.13-14.01, p = 0.041) but in contrast, PS ≥ 2 (p = 0.475) and CCI ≥ 2 (p = 0.939) were not predictive. Conclusions: At our institution, very few pts ≥ 75 years received multimodality therapy for localized GE cancers. Surgery was the only treatment modality associated with a significant survival advantage, and additional chemo and/or RT did not further improve OS. The only predictor for having surgery was age. Consequently, future studies should consider comprehensive assessment for surgery so that eligible elderly pts can benefit.

Comparison of chemoradiotherapy (CRT) with carboplatin/paclitaxel (CP) versus cisplatin/5-FU (CF) for esophageal or junctional cancer: Experience from the Princess Margaret Cancer Centre

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Background: The optimal CRT regimen for neoadjuvant or definitive treatment of locoregional esophageal or gastroesophageal junctional (GEJ) cancer is uncertain. There has been no direct comparison between concurrent Cisplatin/5-FU (CF) as per the CALGB 9781 trial (50.4 Gy) or Carboplatin/Paclitaxel (CP) as per the CROSS trial (41.4 Gy). Methods: A retrospective analysis comparing CF and CP was performed in all patients (pts) with locoregional esophageal or GEJ cancer treated in 2012-2014. Overall survival (OS) and disease-free survival (DFS) were assessed via uni- and multivariable Cox proportional hazards regression, adjusting for age, performance status and Charlson comorbidity index. Pathological complete response (pCR) rates were compared using Fisher’s exact test. Results: 64/86 (74%) pts were male. Median age was 64 years (range: 34-84). Primary sites were esophageal (56%, with 60% squamous histology) and GEJ (44%, with 11% squamous). 22 pts received CRT in 2012 (100% CF), 33 pts in 2013 (58% CF, 42% CP) and 31 pts in 2014 (16% CF, 84% CP). Surgery was undertaken in 19 (41%) CF and 27 (68%) CP pts. Median follow-up was 38 months. We found no significant OS difference between CF and CP overall (HR 0.82, 95% CI: 0.43-1.56, p = 0.55) or in the subgroup having surgery (n = 46; HR 2.01, 95% CI: 0.62-6.55, p = 0.25). However, in the subgroup without surgery (n = 40), CF (n = 27) was superior to CP (n = 13)(HR 0.11, 95% CI: 0.03-0.38, p < 0.001). OS was similar by histology (adenocarcinoma/squamous) in all-comers (p = 0.96), and in CF (p = 0.66) and CP subgroups (p = 0.66). DFS results were similar to OS. There was a non-significant numerical difference in pCR rates between CF (31%) and CP (18%) (p = 0.45). Conclusions: Survival is similar for CF and CP CRT regimens in patients undergoing trimodality therapy. pCR rates were comparable but lower than previously reported. In contrast, in the absence of surgical resection, CP given for CRT results in significantly inferior outcomes. Clinicians may prefer CP for surgical candidates given its toxicity profile. However, when treating with definitive CRT, CF may be preferable to CP as a standard regimen.

Sorafenib treatment in recurrent hepatocellular carcinoma post liver transplantation

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Background: Liver transplantation (LT) is a potentially curative treatment for patients (pts) with selective hepatocellular carcinoma (HCC). HCC recurrence post LT is estimated to be 15-20%. Data on systemic therapy post-recurrence is scarce and limited case series suggest that sorafenib (SOR) may have benefit in this population. We reviewed a single center experience with SOR in recurrent HCC post LT. Methods: A retrospective review was conducted on patients with recurrent HCC post LT at University Health Network (UHN) who were treated with SOR. Pt characteristics were collected including age, gender, comorbidities, background liver disease, type of LT, and time to recurrence after LT. Treatment information collected included: initial SOR dose and subsequent adjustments, adverse events (AEs), duration of treatment and survival. Results: Between 2006 and 2016, 24 patients were identified. The average age was 60 years (range: 18-72), most patients were male (20/4), living/cadaveric transplant: 11/13. HCC etiology included hepatitis B (10), alcohol (4), NASH (3), hepatitis C (2), hemochromatosis (2), Budd-Chiari (2) and unknown (1). The average time to recurrence of HCC was 16.08 (range: 1.5-60) months post LT. There was a bimodal time to recurrence with a median of 6 months. SOR starting doses were 200 mg BID in 18 pts, 300 mg BID in 1 and 400 mg BID in 4. 14 pts required dose adjustment due to AEs, mainly relating to fatigue and palmar-plantar syndrome. The median time on treatment was 2.5 (range: 0.25-37) months, 4/24 patients were on treatment > 6 months. The average time to progression on SOR and/or discontinuation due to AEs was 4.30 (+/- 7.2) months. Conclusions: SOR is reasonably tolerated in patients with recurrent HCC post LT, with expected AE profiles. In this small case series, the median time on sorafenib was short and estimated time to progression was shorter than that in non-transplant HCC population. Overall, sorafenib has limited activity in this population, but selected patients may derive extended benefit. Better understanding of responders and investigations of other therapies are needed for this population.