Plasma versus tissue tumor mutational burden as biomarkers of durvalumab plus tremelimumab response in patients with metastatic colorectal cancer in the CO.26 trial.

PURPOSE: Tissue derived tumor mutation burden (TMB) of ≥10 mutations/Mb is a histology agnostic biomarker for the immune checkpoint inhibitor (ICI) pembrolizumab. However, the dataset on which this was validated lacked colorectal cancers (CRCs), and there is limited evidence for immunotherapy benefit in CRC using this threshold. PATIENTS AND METHODS: CO.26 was a randomized phase II study of 180 patients comparing durvalumab and tremelimumab (D+T, n=119 patients) versus best supportive care (BSC, n=61 patients). ctDNA sequencing was available for 168 patients (n=118 D+T, n=50), of which 165 had evaluable plasma TMB (pTMB). Tissue sequencing was available for 108 patients. Optimal thresholds for stratifying patients based on overall survival were determined using a minimal p-value approach. This report includes the final overall survival analysis. RESULTS: Tissue TMB ≥10 mutations/Mb was not predictive of benefit from D+T compared to BSC in microsatellite stable (MSS) metastatic CRC (HR 0.71 [95% CI:0.28-1.80], p=0.47). No tissue TMB threshold could identify a high TMB group that benefited from ICI. In contrast, plasma TMB (pTMB) ≥28 mutations/Mb was predictive of benefit from D+T (HR=0.34 [95%CI:0.13-0.85], p=0.022), as was clonal pTMB ≥10.6 mutations/Mb (HR=0.10 [95%CI:0.014-0.79], p=0.029) and subclonal pTMB ≥25.9/Mb (HR=0.20 [95% CI:0.061-0.69], p=0.010). Higher pTMB was associated with length of time on cytotoxic agents (p=0.021) and prior anti-EGFR exposure (p=2.44x10-06). CONCLUSION: pTMB derived from either clonal or subclonal mutations may identify a group more likely to benefit from immunotherapy, though validation is required. Tissue TMB provided no predictive utility for immunotherapy in this trial.

Pembrolizumab Plus mFOLFOX7 or FOLFIRI for Microsatellite Stable/Mismatch Repair-Proficient Metastatic Colorectal Cancer: KEYNOTE-651 Cohorts B and D.

BACKGROUND: The phase 1b KEYNOTE-651 study evaluated pembrolizumab plus chemotherapy in microsatellite stable or mismatch repair-proficient metastatic colorectal cancer. PATIENTS AND METHODS: Patients with microsatellite stable or mismatch repair-proficient metastatic colorectal cancer received pembrolizumab 200 mg every 3 weeks plus 5-fluorouracil, leucovorin, oxaliplatin (previously untreated; cohort B) or 5-fluorouracil, leucovorin, irinotecan (previously treated with fluoropyrimidine plus oxaliplatin; cohort D) every 2 weeks. Primary end point was safety; investigator-assessed objective response rate per RECIST v1.1 was secondary and biomarker analysis was exploratory. RESULTS: Thirty-one patients were enrolled in cohort B and 32 in cohort D; median follow-up was 30.2 and 33.5 months, respectively. One dose-limiting toxicity (grade 3 small intestine obstruction) occurred in cohort D. In cohort B, grade 3 or 4 treatment-related adverse events (AEs) occurred in 18 patients (58%), most commonly neutropenia and decreased neutrophil count (n = 5 each). In cohort D, grade 3 or 4 treatment-related AEs occurred in 17 patients (53%), most commonly neutropenia (n = 7). No grade 5 treatment-related AEs occurred. Objective response rate was 61% in cohort B (KRAS wildtype: 71%; KRAS mutant: 53%) and 25% in cohort D (KRAS wildtype: 47%; KRAS mutant: 6%). In both cohorts, PD-L1 combined positive score and T-cell-inflamed gene expression profiles were higher and HER2 expression was lower in responders than nonresponders. No association between tumor mutational burden and response was observed. CONCLUSION: Pembrolizumab plus 5-fluorouracil, leucovorin, oxaliplatin/5-fluorouracil, leucovorin, irinotecan demonstrated an acceptable AE profile. Efficacy data appeared comparable with current standard of care (including by KRAS mutation status). Biomarker analyses were hypothesis-generating, warranting further exploration. GOV IDENTIFIER: ClinicalTrials.gov; NCT03374254.

Pembrolizumab Plus Binimetinib With or Without Chemotherapy for MSS/pMMR Metastatic Colorectal Cancer: Outcomes From KEYNOTE-651 Cohorts A, C, and E.

BACKGROUND: Cohorts A, C, and E of the phase Ib KEYNOTE-651 study evaluated pembrolizumab + binimetinib ± chemotherapy in microsatellite stable/mismatch repair-proficient metastatic colorectal cancer. PATIENTS AND METHODS: Patients received pembrolizumab 200 mg every 3 weeks plus binimetinib 30 mg twice daily alone (cohort A; previously treated with any chemotherapy) or with 5-fluorouracil, leucovorin, oxaliplatin (cohort C; previously untreated) or 5-fluorouracil, leucovorin, irinotecan (cohort E; previously treated with 1 line of therapy including fluoropyrimidine + oxaliplatin-based regimen) every 2 weeks. Binimetinib dose-escalation to 45 mg twice daily was planned in all cohorts using a modified toxicity probability interval design (target dose-limiting toxicity [DLT], 30%). The primary endpoint was safety; investigator-assessed objective response rate was secondary. RESULTS: In cohort A, 1/6 patients (17%) had DLTs with binimetinib 30 mg; none occurred in 14 patients with 45 mg. In cohort C, 3/9 patients (33%) had DLTs with binimetinib 30 mg; dose was not escalated to 45 mg. In cohort E, 1/5 patients (20%) had DLTs with binimetinib 30 mg; 5/10 patients (50%) had DLTs with 45 mg. Enrollment was stopped in cohort E binimetinib 45 mg and deescalated to 30 mg; 2/4 additional patients (50%) had DLTs with binimetinib 30 mg (total 3/9 [33%] had DLTs with binimetinib 30 mg). Objective response rate was 0% in cohort A, 9% in cohort C, and 15% in cohort E. CONCLUSION: Per DLT criteria, binimetinib + pembrolizumab (cohort A) was tolerable, binimetinib + pembrolizumab + 5-fluorouracil, leucovorin, oxaliplatin (cohort C) did not qualify for binimetinib dose escalation to 45 mg, and binimetinib + pembrolizumab + 5-fluorouracil, leucovorin, irinotecan (cohort E) required binimetinib dose reduction from 45 to 30 mg. No new safety findings were observed across cohorts. There was no apparent additive efficacy when binimetinib + pembrolizumab was added to chemotherapy. Data did not support continued enrollment in cohorts C and E.

Circulating Oncometabolite 2-hydroxyglutarate as a Potential Biomarker for Isocitrate Dehydrogenase (IDH1/2) Mutant Cholangiocarcinoma.

Isocitrate dehydrogenase (IDH) enzymes catalyze the decarboxylation of isocitrate to alpha-ketoglutarate (αKG). IDH1/2 mutations preferentially convert αKG to R-2-hydroxyglutarate (R2HG), resulting in R2HG accumulation in tumor tissues. We investigated circulating 2-hydroxyglutate (2HG) as potential biomarkers for patients with IDH-mutant (IDHmt) cholangiocarcinoma (CCA). R2HG and S-2-hydroxyglutarate (S2HG) levels in blood and tumor tissues were analyzed in a discovery cohort of patients with IDHmt glioma and CCA. Results were validated in cohorts of patients with CCA and clear-cell renal cell carcinoma. The R2HG/S2HG ratio (rRS) was significantly elevated in tumor tissues, but not in blood for patients with IDHmt glioma, while circulating rRS was elevated in patients with IDHmt CCA. There were overlap distributions of circulating R2HG and total 2HG in patients with both IDHmt and wild-type (IDHwt) CCA, while there was minimal overlap in rRS values between patients with IDHmt and IDHwt CCA. Using the rRS cut-off value of 1.5, the sensitivity of rRS was 90% and specificity was 96.8%. Circulating rRS is significantly increased in patients with IDHmt CCA compare with patients with IDHwt CCA. Circulating rRS is a sensitive and specific surrogate biomarker for IDH1/2 mutations in CCA. It can potentially be used as a tool for monitoring IDH-targeted therapy.

Liver Metastases and Immune Checkpoint Inhibitor Efficacy in Patients With Refractory Metastatic Colorectal Cancer: A Secondary Analysis of a Randomized Clinical Trial.

Importance: Immune checkpoint inhibitors (ICIs) have limited activity in microsatellite-stable (MSS) or mismatch repair-proficient (pMMR) colorectal cancer. Recent findings suggest the efficacy of ICIs may be modulated by the presence of liver metastases (LM). Objective: To investigate the association between the presence of LM and ICI activity in advanced MSS colorectal cancer. Design, Setting, and Participants: In this secondary analysis of the Canadian Cancer Trials Group CO26 (CCTG CO.26) randomized clinical trial, patients with treatment-refractory colorectal cancer were randomized in a 2:1 fashion to durvalumab plus tremelimumab or best supportive care alone between August 10, 2016, and June 15, 2017. The primary end point was overall survival (OS) with 80% power and 2-sided α = .10. The median follow-up was 15.2 (0.2-22.0) months. In this post hoc analysis performed from February 11 to 14, 2022, subgroups were defined based on the presence or absence of LM and study treatments. Intervention: Durvalumab plus tremelimumab or best supportive care. Main Outcomes and Measures: Hazard ratios (HRs) and 90% CIs were calculated based on a stratified Cox proportional hazards regression model. Plasma tumor mutation burden at study entry was determined using a circulating tumor DNA assay. The primary end point of the study was OS, defined as the time from randomization to death due to any cause; secondary end points included progression-free survival (PFS) and disease control rate (DCR). Results: Of 180 patients enrolled (median age, 65 [IQR, 36-87] years; 121 [67.2%] men; 19 [10.6%] Asian, 151 [83.9%] White, and 10 [5.6%] other race or ethnicity), LM were present in 127 (70.6%). For patients with LM, there was a higher proportion of male patients (94 of 127 [74.0%] vs 27 of 53 [50.9%]; P = .005), and the time from initial cancer diagnosis to study entry was shorter (median, 40 [range, 8-153] vs 56 [range, 14-181] months; P = .001). Plasma tumor mutation burden was significantly higher in patients with LM. Patients without LM had significantly improved PFS with durvalumab plus tremelimumab (HR, 0.54 [90% CI, 0.35-0.96]; P = .08; P = .02 for interaction). Disease control rate was 49% (90% CI, 36%-62%) in patients without LM treated with durvalumab plus tremelimumab, compared with 14% (90% CI, 6%-38%) in those with LM (odds ratio, 5.70 [90% CI, 1.46-22.25]; P = .03). On multivariable analysis, patients without LM had significantly improved OS and PFS compared with patients with LM. Conclusions and Relevance: In this secondary analysis of the CCTG CO.26 study, the presence of LM was associated with worse outcomes for patients with advanced colorectal cancer. Patients without LM had improved PFS and higher DCR with durvalumab plus tremelimumab. Liver metastases may be associated with poor outcomes of ICI treatment in advanced colorectal cancer and should be considered in the design and interpretation of future clinical studies evaluating this therapy.

Plasma Cetuximab Concentrations Correlate With Survival in Patients With Advanced KRAS Wild Type Colorectal Cancer.

BACKGROUND: Cetuximab is a standard of care therapy for patients with RAS wild-type (WT) advanced colorectal cancer. Limited data suggest a wide variation in cetuximab plasma concentrations after standard dosing regimens. We correlated cetuximab plasma concentrations with survival and toxicity. METHODS: The CO. 20 study randomized patients with RAS WT advanced colorectal cancer in a 1:1 ratio to cetuximab 400 mg/m2 intravenously followed by weekly maintenance of 250 mg/m2, plus brivanib 800 mg orally daily or placebo. Blood samples obtained at week 5 precetuximab treatment were analyzed by ELISA. Patients were grouped into tertiles based on plasma cetuximab concentrations. Cetuximab concentration tertiles were correlated with survival outcomes and toxicity. Patient demographic and biochemical parameters were evaluated as co-variables. RESULTS: Week 5 plasma cetuximab concentrations were available for 591 patients (78.8%). The median overall survival (OS) was 11.4 months and 7.8 months for patients in the highest (T3) and lowest tertiles (T1) respectively. On multivariable analysis, plasma cetuximab concentration was associated with OS (HR 0.66, 95% confidence interval [CI]: 0.53-0.83, P < .001, T3 vs. T1), and a trend towards progression-free survival (HR 0.82, 95% CI: 0.66-1.02, P = .07, T3 vs. T1). There was no association between cetuximab concentration and skin toxicity or diarrhea. CONCLUSION: The standard cetuximab dosing regimen may not be optimal for all patients. Further pharmacokinetic studies are needed to optimize cetuximab dosing given the potential improvement in OS.

Combination of clinical, radiomic, and "delta" radiomic features in survival prediction of metastatic gastroesophageal adenocarcinoma.

Objectives: To identify combined clinical, radiomic, and delta-radiomic features in metastatic gastroesophageal adenocarcinomas (GEAs) that may predict survival outcomes. Methods: A total of 166 patients with metastatic GEAs on palliative chemotherapy with baseline and treatment/follow-up (8-12 weeks) contrast-enhanced CT were retrospectively identified. Demographic and clinical data were collected. Three-dimensional whole-lesional radiomic analysis was performed on the treatment/follow-up scans. "Delta" radiomic features were calculated based on the change in radiomic parameters compared to the baseline. The univariable analysis (UVA) Cox proportional hazards model was used to select clinical variables predictive of overall survival (OS) and progression-free survival (PFS) (p-value <0.05). The radiomic and "delta" features were then assessed in a multivariable analysis (MVA) Cox model in combination with clinical features identified on UVA. Features with a p-value <0.01 in the MVA models were selected to assess their pairwise correlation. Only non-highly correlated features (Pearson's correlation coefficient <0.7) were included in the final model. Leave-one-out cross-validation method was used, and the 1-year area under the receiver operating characteristic curve (AUC) was calculated for PFS and OS. Results: Of the 166 patients (median age of 59.8 years), 114 (69%) were male, 139 (84%) were non-Asian, and 147 (89%) had an Eastern Cooperative Oncology Group (ECOG) performance status of 0-1. The median PFS and OS on treatment were 3.6 months (95% CI 2.86, 4.63) and 9 months (95% CI 7.49, 11.04), respectively. On UVA, the number of chemotherapy cycles and number of lesions at the end of treatment were associated with both PFS and OS (p < 0.001). ECOG status was associated with OS (p = 0.0063), but not PFS (p = 0.054). Of the delta-radiomic features, delta conventional HUmin, delta gray-level zone length matrix (GLZLM) GLNU, and delta GLZLM LGZE were incorporated into the model for PFS, and delta shape compacity was incorporated in the model for OS. Of the treatment/follow-up radiomic features, shape compacity and neighborhood gray-level dependence matrix (NGLDM) contrast were used in both models. The combined 1-year AUC (Kaplan-Meier estimator) was 0.82 and 0.81 for PFS and OS, respectively. Conclusions: A combination of clinical, radiomics, and delta-radiomic features may predict PFS and OS in GEAs with reasonable accuracy.

Optimizing the number of variants tracked to follow disease burden with circulating tumor DNA assays in metastatic colorectal cancer.

Background: The number of somatic mutations detectable in circulating tumor DNA (ctDNA) is highly heterogeneous in metastatic colorectal cancer (mCRC). The optimal number of mutations required to assess disease kinetics is relevant and remains poorly understood. Objectives: To determine whether increasing panel breadth (the number of tracked variants in a ctDNA assay) would alter the sensitivity in detecting ctDNA in patients with mCRC. Design: We used archival tissue sequencing to perform an in silico assessment of the optimal number of tracked mutations to detect and monitor disease kinetics in mCRC using sequencing data from the Canadian Cancer Trials Group CO.26 trial. Methods: For each patient, 1, 2, 4, 8, 12, or 16 of the most clonal (highest variant allele frequency) somatic variants were selected from archival tissue-based whole-exome sequencing and assessed for the proportion of variants detected in matched ctDNA at baseline, week 8, and progression timepoints. Results: Data from 110 patients were analyzed. Genes most frequently encountered among the top four highest VAF variants in archival tissue were TP53 (51.9% of patients), APC (43.3%), KRAS (42.3%), and SMAD4 (9.6%). While the frequency of detecting at least one tracked variant increased when expanding beyond variant pool sizes of 1 and 2 in baseline (p = 0.0030) and progression (p = 0.0030) ctDNA samples, we observed no significant benefit to increases in variant pool size past four variants in any of the ctDNA timepoints (p < 0.05). Conclusion: While increasing panel breadth beyond two tracked variants improved variant re-detection in ctDNA samples from patients with treatment refractory mCRC, increases beyond four tracked variants yielded no significant improvement in variant re-detection.

Differential prognostic significance of sarcopenia in metastatic esophageal squamous and adenocarcinoma.

BACKGROUND: Sarcopenia indicates poor prognosis in various malignancies. We evaluated the association of sarcopenia with overall (OS) and progression-free survival (PFS) in metastatic esophageal cancer (MEC) patients, a population often presenting with poor nutritional status. METHODS: In newly diagnosed MEC patients managed at the Princess Margaret (PM) Cancer Centre (diagnosed 2006-2015), total muscle area, visceral adiposity (VA), and subcutaneous adiposity (SA) were quantified on abdominal computed tomography at L3. Sarcopenia was determined using published cutoffs, based on sex and height. RESULTS: Of 202 MEC patients, most were male (166/82%), < 65 years (116/57%), and had adenocarcinoma histology (141/70%); 110/54% had recurrent MEC after initial curative-intent treatment; 92/46% presented with de novo MEC. At stage IV diagnosis, 20/10% were underweight, 97/48% were normal-weight and 84/42% were overweight/obese; 103/51% were sarcopenic. Sarcopenia was associated with worse median OS (4.6 vs. 7.9 months; log-rank p = 0.03) and 1-year survival, even after adjusting for other body composition variables (e.g., BMI, VA, and SA): adjusted-HR 1.51 [95% CI 1.1-2.2, p = 0.02]. In post hoc analysis, sarcopenia was highly prognostic in adenocarcinomas (p = 0.003), but not squamous cell carcinomas (SCC). In patients receiving palliative systemic treatment (104/51%), sarcopenia was associated with shorter PFS (p = 0.004) in adenocarcinoma patients (75/72%). CONCLUSIONS: In metastatic esophageal adenocarcinomas, sarcopenia is associated with worse PFS and OS. In metastatic esophageal SCC, there was a non-significant trend for worse PFS but no association with OS. In order to offset the poor prognosis associated with sarcopenia particularly in metastatic esophageal adenocarcinoma patients, future research should focus on possible countermeasures.

Comparison of Four Clinical Prognostic Scores in Patients with Advanced Gastric and Esophageal Cancer.

BACKGROUND: Prognostic scores that can identify patients at risk for early death are needed to aid treatment decision-making and patient selection for clinical trials. We compared the accuracy of four scores to predict early death (within 90 days) and overall survival (OS) in patients with metastatic gastric and esophageal (GE) cancer. METHODS: Advanced GE cancer patients receiving first-line systemic therapy were included. Prognostic risks were calculated using: Royal Marsden Hospital (RMH), MD Anderson Cancer Centre (MDACC), Gustave Roussy Immune (GRIm-Score), and MD Anderson Immune Checkpoint Inhibitor (MDA-ICI) scores. Overall survival (OS) was estimated using the Kaplan-Meier method. Cox proportional hazards models were used to analyze associations between prognostic scores and OS. The predictive discrimination was estimated using Harrell's c-index. Predictive ability for early death was measured using time-dependent AUCs. RESULTS: In total, 451 patients with metastatic GE cancer were included. High risk patients had shorter OS for all scores (RMH high- vs. low-risk median OS 7.9 vs. 12.2 months, P < .001; MDACC 6.8 vs. 11.9 months P < .001; GRIm-Score 5.3 vs. 13 months, P < .001; MDA-ICI 8.2 vs. 12.2 months, P < .001). On multivariable analysis, each prognostic score was significantly associated with OS. The GRIm-Score had the highest predictive discrimination and predictive ability for early death. CONCLUSIONS: The GRIm-Score had the highest accuracy in predicting early death and OS. Clinicians may use this score to identify patients at higher risk of early death to guide treatment decisions including clinical trial enrolment. This score could also be used as a stratification factor in future clinical trial designs.

Circulating Tumor DNA Identifies Diverse Landscape of Acquired Resistance to Anti-Epidermal Growth Factor Receptor Therapy in Metastatic Colorectal Cancer.

PURPOSE: Anti-epidermal growth factor receptor (EGFR) antibodies are effective treatments for metastatic colorectal cancer. Improved understanding of acquired resistance mechanisms may facilitate circulating tumor DNA (ctDNA) monitoring, anti-EGFR rechallenge, and combinatorial strategies to delay resistance. METHODS: Patients with treatment-refractory metastatic colorectal cancer (n = 169) enrolled on the CO.26 trial had pre-anti-EGFR tissue whole-exome sequencing (WES) compared with baseline and week 8 ctDNA assessments with the GuardantOMNI assay. Acquired alterations were compared between patients with prior anti-EGFR therapy (n = 66) and those without. Anti-EGFR therapy occurred a median of 111 days before ctDNA assessment. RESULTS: ctDNA identified 12 genes with increased mutation frequency after anti-EGFR therapy, including EGFR (P = .0007), KRAS (P = .0017), LRP1B (P = .0046), ZNF217 (P = .0086), MAP2K1 (P = .018), PIK3CG (P = .018), BRAF (P = .048), and NRAS (P = .048). Acquired mutations appeared as multiple concurrent subclonal alterations, with most showing decay over time. Significant increases in copy-gain frequency were noted in 29 genes after anti-EGFR exposure, with notable alterations including EGFR (P < .0001), SMO (P < .0001), BRAF (P < .0001), MET (P = .0002), FLT3 (P = .0002), NOTCH4 (P = .0006), ERBB2 (P = .004), and FGFR1 (P = .006). Copy gains appeared stable without decay 8 weeks later. There were 13 gene fusions noted among 11 patients, all but one of which was associated with prior anti-EGFR therapy. Polyclonal resistance was common with acquisition of ≥ 10 resistance related alterations noted in 21% of patients with previous anti-EGFR therapy compared with 5% in those without (P = .010). Although tumor mutation burden (TMB) did not differ pretreatment (P = .63), anti-EGFR exposure increased TMB (P = .028), whereas lack of anti-EGFR exposure resulted in declining TMB (P = .014). CONCLUSION: Paired tissue and ctDNA sequencing identified multiple novel mutations, copy gains, and fusions associated with anti-EGFR therapy that frequently co-occur as subclonal alterations in the same patient.

Impact of Sites of Metastatic Dissemination on Survival in Advanced Gastroesophageal Adenocarcinoma.

INTRODUCTION: Metastatic gastroesophageal adenocarcinoma (GEA) is a heterogeneous disease with an overall poor prognosis. The impact of sites of metastatic dissemination on survival is not well characterized. This study aimed to evaluate whether certain sites of metastatic disease impacts survival. METHODS: A retrospective analysis of 375 patients with metastatic GEA treated at the Princess Margaret Cancer Centre from 2006 to 2016 was performed. Overall survival (OS) and progression-free survival (PFS) were estimated using the Kaplan-Meier method. Cox proportional hazards regression models were used to assess the association between sites of metastases and OS adjusting for baseline patient characteristics. RESULTS: Median duration of follow-up was 47.8 months. Median OS in this cohort was 11.8 months (95% CI: 10.2-12.9 months). Patients with lymph node only disease, compared to those with other sites of metastases, had the longest median OS (20.4 vs. 10.6 months; p < 0.001) and PFS (11.4 vs. 6.3 months; p < 0.001). On multivariable analysis adjusting for relevant clinical factors including age, sex, and Eastern Cooperative Oncology Group performance status, the presence of lung (HR 1.67, 95% CI: 1.23-2.26; p < 0.001) or bone metastases (HR 1.84, 95% CI: 1.31-2.59; p < 0.001) were independently associated with shorter OS. The majority of patients (68%) were treated with palliative intent first-line platinum-based chemotherapy. DISCUSSION/CONCLUSION: Patients with metastatic GEA have an overall poor prognosis. The presence of lung or bone metastases is an independent risk factor for decreased survival. Prognostic models incorporating sites of metastasis should be considered in the clinical evaluation of metastatic GEA.

The Association of Fractal Dimension with Vascularity and Clinical Outcomes in Glioblastoma.

BACKGROUND: Growing evidence indicates fractal analysis (FA) has potential as a computational tool to assess tumor microvasculature in glioblastoma (GBM). As fractal parameters of microvasculature have shown to be reliable quantitative biomarkers in brain tumors, there has been similar success in measuring the architecture of tumor tissue using FA in other tumor types. However, evaluating fractal parameters of tissue structure in relation to the microvasculature has not yet been implemented in GBM. We aimed to assess the utility of this methodology in quantifying structural characteristics of GBM cytoarchitecture and vascularity by correlating fractal parameters with gene expression. METHODS: Formalin-fixed paraffin-embedded specimens were retrospectively collected from 43 patients following resection of a newly diagnosed GBM; 4 normal brain specimens were obtained from epilepsy surgeries as controls. Tumor samples were processed using FA employing a software-based box-counting method algorithm and custom messenger RNA expression assays. Fractal parameters were then correlated with clinical features, outcomes, and a panel of 92 genes associated with vascularity and angiogenesis. RESULTS: Statistical analysis demonstrated that fractal-based indices were not adequate parameters for distinction of GBM cytoarchitecture compared with normal brain specimens. Correlation analysis of our gene expression findings suggested that hematoxylin and eosin-based FA may have adequate sensitivity to detect associations with vascular gene expression. CONCLUSIONS: The combination of neuropathological assessment and histology does not provide optimized data for FA in GBM. However, an association between FA and gene expression in GBM of genes pertaining to cytoarchitecture and angiogenesis warrants further investigation.

Combined 18 F-FDG PET/CT Radiomics and Sarcopenia Score in Predicting Relapse-Free Survival and Overall Survival in Patients With Esophagogastric Cancer.

PURPOSE: The aim of this study was to determine if radiomic features combined with sarcopenia measurements on pretreatment 18 F-FDG PET/CT can improve outcome prediction in surgically treated adenocarcinoma esophagogastric cancer patients. PATIENTS AND METHODS: One hundred forty-five esophageal adenocarcinoma patients with curative therapeutic intent and available pretreatment 18 F-FDG PET/CT were included. Textural features from PET and CT images were evaluated using LIFEx software ( lifexsoft.org ). Sarcopenia measurements were done by measuring the Skeletal Muscle Index at L3 level on the CT component. Univariable and multivariable analyses were conducted to create a model including the radiomic parameters, clinical features, and Skeletal Muscle Index score to predict patients' outcome. RESULTS: In multivariable analysis, we combined clinicopathological parameters including ECOG, surgical T, and N staging along with imaging derived sarcopenia measurements and radiomic features to build a predictor model for relapse-free survival and overall survival. Overall, adding sarcopenic status to the model with clinical features only (likelihood ratio test P = 0.03) and CT feature ( P = 0.0037) improved the model fit for overall survival. Similarly, adding sarcopenic status ( P = 0.051), CT feature ( P = 0.042), and PET feature ( P = 0.011) improved the model fit for relapse-free survival. CONCLUSIONS: PET and CT radiomics derived from combined PET/CT integrated with clinicopathological parameters and sarcopenia measurement might improve outcome prediction in patients with nonmetastatic esophagogastric adenocarcinoma.

Optimism Bias in the Design of Phase III Randomized Control Trials Evaluating PD-1/PD-L1 Targeting Monoclonal Antibodies.

BACKGROUND: Many randomized control trials (RCTs) evaluating programmed death receptor-1 (PD-1)/programmed death ligand-1 (PD-L1) targeting monoclonal antibodies (mAbs) have been completed or are in progress. We examined hypothesized hazard ratios (HHRs) and observed hazard ratios (OHRs) from published RCTs evaluating these mAbs. METHODS: Publications of RCTs evaluating at least one PD-1/PD-L1 targeting mAbs approved by the US Food and Drug Administration were identified through PubMed searches. The primary reports of RCTs were retrieved. Two investigators extracted HHR, OHR for the primary endpoint among other data elements independently. The differences (∆HR) in HHR and OHR were analyzed statistically. A separate search was conducted for secondary reports after longer follow-ups, the updated OHR was extracted. RESULTS: Forty-nine RCTs enrolling 36 867 patients were included. The mean HHR and OHR were 0.672 and 0.738 respectively. The mean ∆HR was 0.067 (range: -0.300 to 0.895; 95% confidence interval (CI), 0.003-0.130). HHR was met or exceeded in 22 (45%) RCTs. OHR was ≥ 1.0 in 6 RCTs (12%). PD-L1 expression was not associated with the magnitude of effect. Of 18 RCTs with follow-up reports, the magnitude of benefit decreased in 8 RCTs with extended follow-ups. CONCLUSION: The majority of published RCTs evaluating PD-1/PD-L1 targeting mAbs did not achieve their hypothesized magnitude of benefit. The optimism bias requires attention from the cancer clinical research community given the number of these agents in development and the intense interest in evaluating these agents in a variety of disease settings.

Preoperative and Postoperative Approaches to Gastroesophageal Cancer: What is All the Fuss About.

Gastroesophageal cancers carry poor prognoses, and are a leading cause of cancer-related morbidity and mortality worldwide. Even in those with resectable disease, more than half of patients treated with surgery alone experience disease recurrence. Multimodality approaches using preoperative and postoperative chemotherapy and/or radiotherapy have been established, resulting in incremental improvements in outcomes. Globally, there is no standardized approach, and treatment varies with geographic location. The question remains of how to select the optimal perioperative treatment that will maximize benefit for patients while avoiding toxicities from unnecessary therapies. This article reviews currently available evidence supporting preoperative and postoperative therapy in gastroesophageal cancers, with an emphasis on recent practice-changing trials and ongoing areas of investigation, including the role of immune checkpoint inhibition and biomarker-guided treatment.

Phase I pharmacokinetic study of single agent trametinib in patients with advanced cancer and hepatic dysfunction.

BACKGROUND: Trametinib is an oral MEK 1/2 inhibitor, with a single agent recommended phase 2 dose (RP2D) of 2 mg daily (QD). This study was designed to evaluate RP2D, maximum tolerated dose (MTD), and pharmacokinetic (PK) profile of trametinib in patients with advanced solid tumors who had various degrees of hepatic dysfunction (HD). METHODS: Advanced cancer patients were stratified into 4 HD groups based on Organ Dysfunction Working Group hepatic function stratification criteria: normal (Norm), mild (Mild), moderate (Mod), severe (Sev). Dose escalation was based on "3 + 3" design within each HD group. PK samples were collected at cycle 1 days 15-16. RESULTS: Forty-six patients were enrolled with 44 evaluable for safety [Norm=17, Mild=7, Mod (1.5 mg)=4, Mod (2 mg)=5, Sev (1 mg)=9, Sev (1.5 mg)=2] and 22 for PK analysis. Treatment related adverse events were consistent with prior trametinib studies. No treatment related deaths occurred. Dose limiting toxicities (DLTs) were evaluable in 15 patients (Mild=6, Mod (1.5 mg)=3, Mod (2 mg)=2, Sev (1 mg)=3 and Sev (1.5 mg)=1). One DLT (grade 3 acneiform rash) was observed in a Sev patient (1.5 mg). Dose interruptions or reductions due to treatment related adverse events occurred in 15 patients (34%) [Norm=9, 53%; Mild=2, 29%; Mod (1.5 mg)=1, 33%; Mod (2 mg)=2, 33%; Sev (1 mg)=1, 11%; Sev (1.5 mg)=1; 50%]. There were no significant differences across HD groups for all PK parameters when trametinib was normalized to 2 mg. However, only limited PK data were available for the Mod (n = 3) and Sev (n = 3) groups compared to Norm (n = 10) and Mild (n = 6) groups. Trametinib is heavily protein bound, with no correlation between serum albumin level and unbound trametinib fraction (p = 0.26). CONCLUSIONS: RP2D for trametinib in Mild HD patients is 2 mg QD. There are insufficient number of evaluable patients due to difficulty of patient accrual to declare RP2D and MTD for Mod and Sev HD groups. DLTs were not observed in the highest dose cohorts that reached three evaluable patients - 1.5 mg QD in Mod group, and 1 mg QD in Sev group. TRIAL REGISTRATION: This study was registered in the ClinicalTrials.gov website ( NCT02070549 ) on February 25, 2014. .

Impact of Definitive Chemoradiation on Quality-of-Life Changes for Patients With Anal Cancer: Long-term Results of a Prospective Study.

BACKGROUND: Maintaining and improving quality of life (QOL) are important goals of anal cancer management. This disease is generally curable, with many long-term survivors. OBJECTIVE: Long-term QOL after chemoradiation for patients with anal cancer was evaluated. DESIGN: This was a prospective cohort study. SETTINGS: This study used data from a prospective study of patients with anal cancer who were treated with chemoradiation between 2008 and 2013. PATIENTS: Patients with anal cancer who were treated with image-guided intensity-modulated radiation therapy were included. INTERVENTIONS: English-speaking patients completed European Organization for Research and Treatment of Cancer cancer-specific (C30) and site-specific (CR29) QOL questionnaires at baseline, at end of radiation, at 3 and 6 months, and then annually. MAIN OUTCOMES MEASURES: Long-term QOL was evaluated clinically (a change in score of ≥10 points was considered clinically significant) and statistically (using repeated-measurement analysis) by comparing the subscale scores at 1, 2, and 3 years with baseline scores. Subanalysis compared patients who received a radiation dose of 45 to 54 Gy versus 63 Gy. RESULTS: Ninety-six patients were included (median follow-up of 56.5 months). The symptom and functional scales showed a clinically significant decline at the end of treatment with improvement by 3 months after treatment. There was a long-term statistically significant decline in dyspnea, body image, bowel embarrassment, fecal incontinence, and hair loss, and there was long-term statistically and clinically significant worsening of impotence. Higher radiation dose (63 Gy) was not associated with significantly worse QOL. LIMITATIONS: Limitations included single-institution, single-arm study design, and lack of dose reconstruction (ie, analyses were based on prescribed, rather than delivered, dose). CONCLUSIONS: Patients with anal cancer treated with chemoradiation reported recovery of overall QOL to baseline levels. Specific symptoms remained bothersome, emphasizing the need to address and manage the chemoradiation-induced symptoms, during treatment and in the long term. See Video Abstract at http://links.lww.com/DCR/B905. IMPACTO DE LA QUIMIORRADIACIN DEFINITIVA EN CAMBIOS EN LA CALIDAD DE VIDA DE LOS PACIENTES CON CNCER ANAL RESULTADOS A LARGO PLAZO DE UN ESTUDIO PROSPECTIVE: ANTECEDENTES:Mantener y mejorar la calidad de vida son objetivos importantes del tratamiento del cáncer anal, ya que esta enfermedad generalmente es curable, con muchos sobrevivientes a largo plazo.OBJETIVO:Se evaluó la calidad de vida a largo plazo después de la quimiorradiación en pacientes con cáncer anal.DISEÑO:Este fue un estudio de cohorte prospectivo.ENTORNO CLINICO:Utilizamos datos de un estudio prospectivo en pacientes con cáncer anal tratados con quimiorradiación entre 2008-2013.PACIENTES:Los pacientes con cáncer anal fueron tratados con radioterapia de intensidad modulada guiada por imágenes.INTERVENCIONES:Los pacientes de habla inglesa completaron los cuestionarios de calidad de vida específicos de cáncer (C30) y específicos del sitio (CR29) de la Organización Europea para la Investigación y el Tratamiento del Cáncer al inicio, al final de la radiación, 3 y 6 meses, y luego anualmente.PRINCIPALES MEDIDAS DE RESULTADOS:Se evaluó a largo plazo la calidad de vida clínicamente (un cambio en la puntuación de ≥10 puntos se consideraron clínicamente significativo) y estadísticamente (usando análisis de medición repetida) comparando las subescalas de puntuación al 1, 2, y 3 años. Con puntuaciones de referencia. El subanálisis comparó pacientes que recibieron 45-54 Gy versus 63 Gy.RESULTADOS:Se incluyeron un total de 96 pacientes (mediana de seguimiento: 56,5 meses). La mayoría de las escalas funcionales y de síntomas mostraron una disminución clínicamente significativa al final del tratamiento con una mejoría a los 3 meses posteriores al tratamiento. Hubo una disminución estadísticamente significativa a largo plazo en disnea, imagen corporal, vergüenza intestinal, incontinencia fecal y pérdida de cabello; y hubo un empeoramiento a largo plazo estadística y clínicamente significativo en impotencia. La dosis de radiación más alta (63 Gy) no se asoció con una calidad de vida significativamente peor.LIMITACIONES:Institución única, diseño de estudio de un solo brazo y falta de recomposición de la dosis (es decir, los análisis se basan en la dosis prescrita, en lugar de la administrada).CONCLUSIÓNES:Los pacientes con cáncer anal tratados con quimiorradiación reportaron una recuperación de la QOL en general a los niveles de base. Síntomas específicos siguieron siendo molestos, lo que enfatiza la necesidad de resolver y tartar los síntomas inducidos por la quimiorradiación no solo durante el tratamiento, sino a largo plazo. Consulte Video Resumen en http://links.lww.com/DCR/B905. (Traducción- Dr. Francisco M. Abarca-Rendon).

Anal Adenocarcinoma: A Rare Entity in Need of Multidisciplinary Management.

BACKGROUND: Anal adenocarcinoma is a rare clinical entity for which the optimal management is not defined. OBJECTIVE: This study aimed to describe the multidisciplinary management and outcomes of patients with anal adenocarcinoma. DESIGN: This is a retrospective cohort study. SETTING: This study was conducted at a quaternary cancer center. PATIENTS: Men and women with anal adenocarcinoma treated between 1995 and 2016 were selected. INTERVENTIONS: Fifty-two patients were treated with either chemoradiotherapy or trimodality therapy including radiation therapy, chemotherapy, and surgical resection. MAIN OUTCOME MEASURES: Local failure, regional failure, and distant metastasis rates were estimated using the cumulative incidence method. The Kaplan-Meier method was used to estimate progression-free survival and overall survival. The multivariable Cox proportional hazards model was used to evaluate the clinical predictors of outcome. RESULTS: There was a higher 5-year rate of local failure in patients treated with chemoradiotherapy compared with trimodality therapy (53% vs 10%; p < 0.01). The 5-year incidence of distant metastases was 29% (trimodality therapy) versus 30% (chemoradiotherapy; p = 0.9); adjuvant chemotherapy did not reduce the incidence of distant metastases (p = 0.8). Five-year overall survival was 73% (trimodality therapy) versus 49.4% (chemoradiotherapy; p = 0.1). On multivariable analysis, factors associated with worse overall survival were treatment with chemoradiotherapy, cT3-4 category disease, and node-positive disease. LIMITATIONS: This study is limited by its small sample size and retrospective nature. CONCLUSIONS: Although treatment may continue to be tailored to individual patients, better outcomes with a trimodality therapy approach were observed. See Video Abstract at http://links.lww.com/DCR/B708.ADENOCARCINOMA ANAL: UNA ENTIDAD POCO FRECUENTE EN NECESIDAD DE UN MANEJO MULTIDISCIPLINARIO. ANTECEDENTES: El adenocarcinoma anal es una entidad clínica poco frecuente por lo que aún no se define el manejo óptimo. OBJETIVO: Describir el manejo multidisciplinario y los resultados de los pacientes con adenocarcinoma anal. DISEO: Estudio de cohorte retrospectivo. ENTORNO CLINICO: Centro de cáncer cuaternario. PACIENTES: Hombres y mujeres con adenocarcinoma anal tratados entre 1995 y 2016. INTERVENCIONES: Cincuenta y dos pacientes fueron tratados con quimiorradioterapia o terapia trimodal que incluyó: radioterapia, quimioterapia y resección quirúrgica. PRINCIPALES MEDIDAS DE VALORACION: Se estimaron las tasas de falla local, falla regional y metástasis a distancia mediante el método de incidencia acumulada. Se utilizó el método de Kaplan-Meier para estimar la supervivencia libre de progresión y la supervivencia global. Los riesgos proporcionales de multivariable Cox se utilizaron para evaluar los predictores clínicos de los resultados. RESULTADOS: Hubo una mayor tasa de falla local a cinco años en pacientes tratados con quimiorradioterapia en comparación con terapia trimodal (53% vs 10%; p < 0,01). La incidencia a cinco años de metástasis a distancia fue del 29% (terapia trimodal) versus 30% (quimiorradioterapia) (p = 0,9); la quimioterapia adyuvante no redujo la incidencia de metástasis a distancia (p = 0,8). La supervivencia global a cinco años fue del 73% (terapia trimodal) versus 49,4% (quimiorradioterapia); p = 0,1. En el análisis multivariable, los factores asociados con una peor supervivencia general fueron el tratamiento con quimiorradioterapia, enfermedad de categoría cT3-4 y enfermedad con ganglios positivos. LIMITACIONES: Este estudio está limitado por su pequeño tamaño de muestra y su naturaleza retrospectiva. CONCLUSIONES: Aunque el tratamiento puede seguir adaptándose a pacientes individuales, se observaron mejores resultados con un enfoque TTM. Conslute Video Resumen en http://links.lww.com/DCR/B708. (Traducción- Dr. Francisco M. Abarca-Rendon).

Repurposing Itraconazole and Hydroxychloroquine to Target Lysosomal Homeostasis in Epithelial Ovarian Cancer.

Drug repurposing is an attractive option for oncology drug development. Itraconazole is an antifungal ergosterol synthesis inhibitor that has pleiotropic actions including cholesterol antagonism, inhibition of Hedgehog and mTOR pathways. We tested a panel of 28 epithelial ovarian cancer (EOC) cell lines with itraconazole to define its spectrum of activity. To identify synthetic lethality in combination with itraconazole, a whole-genome drop-out genome-scale clustered regularly interspaced short palindromic repeats sensitivity screen in two cell lines (TOV1946 and OVCAR5) was performed. On this basis, we conducted a phase I dose-escalation study assessing the combination of itraconazole and hydroxychloroquine in patients with platinum refractory EOC (NCT03081702). We identified a wide spectrum of sensitivity to itraconazole across the EOC cell lines. Pathway analysis showed significant involvement of lysosomal compartments, the trans-golgi network and late endosomes/lysosomes; similar pathways are phenocopied by the autophagy inhibitor, chloroquine. We then demonstrated that the combination of itraconazole and chloroquine displayed Bliss defined synergy in EOC cancer cell lines. Furthermore, there was an association of cytotoxic synergy with the ability to induce functional lysosome dysfunction, by chloroquine. Within the clinical trial, 11 patients received at least one cycle of itraconazole and hydroxychloroquine. Treatment was safe and feasible with the recommended phase II dose of 300 and 600 mg twice daily, respectively. No objective responses were detected. Pharmacodynamic measurements on serial biopsies demonstrated limited pharmacodynamic impact. In vitro, itraconazole and chloroquine have synergistic activity and exert a potent antitumor effect by affecting lysosomal function. The drug combination had no clinical antitumor activity in dose escalation. Significance: The combination of the antifungal drug itraconazole with antimalarial drug hydroxychloroquine leads to a cytotoxic lysosomal dysfunction, supporting the rational for further research on lysosomal targeting in ovarian cancer.