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.

Muscle and Adipose Wasting despite Disease Control: Unaddressed Side Effects of Palliative Chemotherapy for Pancreatic Cancer

Muscle and adipose wasting during chemotherapy for advanced pancreatic cancer (aPC) are associated with poor outcomes. We aimed to quantify the contributions of chemotherapy regimen and tumour progression to muscle and adipose wasting and evaluate the prognostic value of each tissue loss. Of all patients treated for aPC from 2013-2019 in Alberta, Canada (n = 504), computed-tomography (CT)-defined muscle and adipose tissue index changes (∆SMI, ∆ATI, cm2/m2) were measured for patients with CT images available both prior to and 12 ± 4 weeks after chemotherapy initiation (n = 210). Contributions of regimen and tumour response to tissue change were assessed with multivariable linear regression. Survival impacts were assessed with multivariable Cox's proportional hazards models. Tissue changes varied widely (∆SMI: -17.8 to +7.3 cm2/m2, ∆ATI: -106.1 to +37.7 cm2/m2) over 116 (27) days. Tumour progression contributed to both muscle and adipose loss (-3.2 cm2/m2, p < 0.001; -12.4 cm2/m2, p = 0.001). FOLFIRINOX was associated with greater muscle loss (-1.6 cm2/m2, p = 0.013) and GEM/NAB with greater adipose loss (-11.2 cm2/m2, p = 0.002). The greatest muscle and adipose losses were independently associated with reduced survival (muscle: HR 1.72, p = 0.007; adipose: HR 1.73, p = 0.012; tertile 1 versus tertile 3). Muscle and adipose losses are adverse effects of chemotherapy and may require regimen-specific management strategies.

Total energy expenditure assessed by 24-h whole-room indirect calorimeter in patients with colorectal cancer: baseline findings from the PRIMe study

BACKGROUND

Total energy expenditure (TEE) determines energy requirements, but objective data in patients with cancer are limited.

OBJECTIVES

We aimed to characterize TEE, investigate its predictors, and compare TEE with cancer-specific predicted energy requirements.

METHODS

This cross-sectional analysis included patients with stages II-IV colorectal cancer from the Protein Recommendation to Increase Muscle (PRIMe) trial. TEE was assessed by 24-h stay in a whole-room indirect calorimeter before dietary intervention and compared with cancer-specific predicted energy requirements (25-30 kcal/kg). Generalized linear models, paired-samples t tests, and Pearson correlation were applied.

RESULTS

Thirty-one patients (56 ± 10 y; body mass index [BMI]: 27.9 ± 5.5 kg/m2; 68% male) were included. Absolute TEE was higher in males (mean difference: 391 kcal/d; 95% CI: 167, 616 kcal/d; P < 0.001), patients with colon cancer (mean difference: 279 kcal/d; 95% CI: 73, 485 kcal/d; P = 0.010), and patients with obesity (mean difference: 393 kcal/d; 95% CI: 182, 604 kcal/d; P < 0.001). Appendicular lean soft tissue (β: 46.72; 95% CI: 34.27, 59.17; P < 0.001) and tumor location (colon-β: 139.69; 95% CI: 19.44, 259.95; P = 0.023) independently predicted TEE when adjusted for sex. Error between measured TEE and energy requirements predicted by 25 kcal/kg (mean difference: 241 kcal/d; 95% CI: 76, 405 kcal/d; P = 0.010) or 30 kcal/kg (mean difference: 367 kcal/d; 95% CI: 163, 571 kcal/d; P < 0.001) was higher for patients with obesity, and proportional error was observed (25 kcal/kg: r = -0.587; P < 0.001; and 30 kcal/kg: r = -0.751; P < 0.001). TEE (mean difference: 25 kcal/kg; 95% CI: 24, 27 kcal/kg) was below predicted requirements using 30 kcal/kg (-430 ± 322 kcal/d; P < 0.001).

CONCLUSIONS

This is the largest study to assess TEE of patients with cancer using whole-room indirect calorimeter and highlights the need for improved assessment of energy requirements in this population. Energy requirements predicted using 30 kcal/kg overestimated TEE by 1.44 times in a controlled sedentary environment and TEE was outside of the predicted requirement range for most. Special considerations are warranted when determining TEE of patients with colorectal cancer, such as BMI, body composition, and tumor location. This is a baseline cross-sectional analysis from a clinical trial registered at clinicaltrials.gov as NCT02788955 (https://clinicaltrials.gov/ct2/show/NCT02788955).

Use of nab-paclitaxel and gemcitabine in pancreatic cancer without granulocyte colony-stimulating factor: A multicenter real-world experience

INTRODUCTION

The metastatic pancreatic adenocarcinoma clinical trial (MPACT) trial established gemcitabine (gem) and nab-paclitaxel (nab) as a standard treatment for pancreatic cancer utilizing granulocyte colony-stimulating factors to manage neutropenia. This was a challenge for jurisdictions that do not use granulocyte colony-stimulating factors in palliative settings. We developed dosage guidelines to dose modify gem and nab without granulocyte colony-stimulating factors. We undertook a retrospective review to determine the efficacy and safety of these dose adjustment guidelines in the real world.

METHODS

A multi-centered, retrospective chart review was performed on pancreatic patients between December 1, 2014, and August 21, 2018. Provincial electronic medical health records were reviewed. Using Log-rank statistics we determined the patient's progression-free survival and overall survival.

RESULTS

Of 248 patients, 209 met patient selection criteria. Patients were excluded if they were lost to follow-up, on gem alone prior to nab/gem combination therapy or did not receive nab or gem. Patients who received nab/gem as first-line therapy had a median progression-free survival of 6.3 months (95% CI, 5.1-7.4), and median overall survival of 11.1 months (95% CI, 9.5-12.8). Those who received gem/nab in the second line had a median progression-free survival of 4.6 months (95% CI, 2.8-6.5), and median overall survival of 19.3 months (95% CI, 12.6-26.0).

CONCLUSIONS

The patient's progression-free survival and overall survival taking nab/gem using our dose modification algorithm were equivalent or superior to the MPACT trial's progression-free survival and overall survival. Gem/nab can be given by our dose modification scheme without granulocyte colony-stimulating factor.

Adiposity in resectable colorectal cancer

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Background: Sarcopenia and myosteatosis affect survival in colorectal cancer (CRC). The role of adiposity is not yet fully elucidated. This study explores visceral and subcutaneous adipose tissue (VAT/SAT) distributions, and how they affect overall (OS), disease-free (DFS) and cancer specific survival (CSS). Methods: This retrospective cohort study, included resected stage I-III CRC in Alberta from January 2007 to December 2009. We excluded recurrent/metastatic disease or no CT scan. This study was approved by the Health Research Ethics Board at the University of Alberta. Body composition parameters were measured from CT scans. Sarcopenia and myosteatosis were defined by cohort-specific cut-off values. Total and visceral fat areas were indexed by height, and cohort-specific cut-offs defined total and visceral obesity (VO). SAT (SC:TFR) and VAT (V:TFR) to total adipose ratios were compared by gender, as described by Fleming. SAT and VAT fat radiodensity (Hounsfield units, HU) was measured and divided into quartiles. Differences between groups were compared with student’s t-test and Fisher Exact test. Cox proportional hazard models were created, adjusting for important covariates, to assess adiposity effects on OS, DFS and CSS. Results: Our cohort included 968 patients with a median follow up of 63.5 months. The majority were stage II (38.6%) and III (51.0%). In total, 67.9% had total obesity and 51.0% had visceral obesity. In males, there was no difference in the incidence of myosteatosis or sarcopenia, regardless of V:TFR or SC:TFR. In women, those with a high V:TFR or SC:TFR had significantly higher incidence of myosteatosis, but not sarcopenia. Men and women with elevated V:TFR had significantly lower VAT and SAT HU (p<0.001, p=0.0113). Those with elevated SC:TFR had significantly higher VAT and SAT HU (p<0.001). VAT and SAT HU was lowest in those with myosteatosis alone (p<0.001; p=0.005). In survival analysis, VO and VAT HU quartiles predicted worse OS in uni-, but not multivariate analysis. SAT HU quartiles predicted worse survival in uni- and multivariate analysis, with the highest quartile of SAT HU predicting increased risk of death (HR 1.35, p=0.037). Adiposity was not predictive of CSS or DFS in uni- or multivariate analysis. Conclusions: This study demonstrated changes in VAT/SAT in relation to well described body composition parameters. SAT HU may have a more important role in OS than visceral adipose characteristics, despite known metabolic characteristics of VAT. True roles of adipose tissue in CRC outcomes remains unclear. VAT/SAT measurements using cross-sectional imaging allows for a detailed analysis and understanding of how adiposity may affect survival. [Table: see text]

Pembrolizumab (pembro) plus binimetinib (bini) with or without chemotherapy (chemo) for metastatic colorectal cancer (mCRC): Results from KEYNOTE-651 cohorts A, C, and E

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Background: Response to antiPD-1 monotherapy is poor in microsatellite stable (MSS)/mismatch-repair proficient (pMMR) mCRC; the combination of antiPD-1 pembro + anti-MEK bini, with or without chemo, may improve upon this limited response. KEYNOTE-651 (NCT03374254) is an open-label phase 1b multicenter trial of pembro + bini (cohort A) or pembro + bini + chemo (mFOLFOX7 in cohort C, FOLFIRI in cohort E) in MSS/pMMR mCRC. Preliminary results from the dose-finding phase at 2 dose levels (DL) of bini are presented. Methods: Patients (pts) had MSS/pMMR mCRC and must have been previously treated with fluoropyrimidine, irinotecan, and oxaliplatin in cohort A, or with fluoropyrimidine + oxaliplatin-based regimen in cohort E; pts were previously untreated in cohort C. Pts received pembro 200 mg Q3W + bini 30 mg BID (cohort A, DL1), pembro 200 mg Q3W+ bini 30 mg BID + mFOLFOX7 Q2W (cohort C, DL1) or pembro 200 mg Q3W + bini 30 mg BID + FOLFIRI Q2W (cohort E, DL1). Bini dose escalation to 45 mg BID (DL2) was planned in cohorts A, C, and E, with a target dose-limiting toxicity (DLT) of 30%. Primary end point was safety (DLT). Secondary end point was ORR. DCR, PFS, and OS were exploratory. ORR, DCR, and PFS were assessed by investigator per RECIST v1.1. Results: Median study follow-up at data cutoff (Oct 15, 2021) was 36 mo (range, 32-43) for cohort A, 17 mo (2-24) for cohort C, and 11 mo (2-25) for cohort E. In cohort A, 1/6 pts (17%) had DLT at DL1; no DLT occurred in 14 pts (0%) at DL2. In cohort A, gr 3/4 TRAEs occurred in 3/6 pts (50%) at DL1 and 8/14 pts (57%) at DL2. In cohort C, 3/9 evaluable pts (33%) had DLT at DL1; thus, bini dose was not escalated to DL2. In cohort C, gr 3/4 TRAEs occurred in 9/11 total pts (82%). In cohort E, 1/5 evaluable pts (20%) had DLT at DL1 and 5/10 evaluable pts (50%) had DLT at DL2. Enrollment was stopped in cohort E, DL2 and bini dose was de-escalated to DL1; 2/4 additional pts (50%) had DLT at DL1 (total 3/9 pts [33%] had DLT in cohort E, DL1). In cohort E, gr 3/4 TRAEs occurred in 5/9 pts (56%) at DL1 and 10/11 total pts (91%) at DL2. No gr 5 TRAEs occurred in any cohort. ORR was 0% in cohort A; limited efficacy was seen in cohorts C and E (Table). Conclusions: Bini could be safely combined with pembro in cohort A. However, with bini + pembro + chemo, the 45-mg dose of bini was not well tolerated and required dose reduction to 30 mg. Addition of bini to pembro + chemo did not improve efficacy; therefore, enrollment was prematurely closed in cohorts C and E. Efficacy by KRAS mutation status will be shown. Clinical trial information: NCT03374254. [Table: see text]

Changes in Survival Outcomes of Patients With Neuroendocrine Neoplasms Over the Past 15 Years: A Real-World Study

BACKGROUND

The past 2 decades have observed a number of advances in therapeutic approaches to patients with neuroendocrine neoplasms (NENs). This study aims to assess whether survival outcomes have changed among patients with NENs over the past 15 years, in a real-world, population-based study.

MATERIALS AND METHODS

We accessed administrative databases within the province of Alberta, Canada, and we reviewed patients with invasive NENs diagnosed 2004 to 2019. Patients were classified according to the year of diagnosis into 3 groups: 2004 to 2008; 2009 to 2013; and 2014 to 2019. Kaplan-Meier survival estimates were used to compare overall survival (OS) according to different baseline characteristics (including the year of diagnosis). Multivariable Cox regression modeling was used to examine factors associated with the risk of death in this cohort.

RESULTS

We included a total of 3431 patients in the study cohort. Using multivariable Cox regression analysis, the following factors were associated with worse survival: older age at diagnosis (hazard ratio [HR]: 3.45; 95% CI [confidence interval]: 2.74-4.35), male sex (HR: 1.38; 95% CI: 1.21-1.56), lung primary site (HR for lung vs. appendicular primary: 1.39; 95% CI: 1.01-1.92), Stage 4 disease (HR: 2.80; 95% CI: 2.38-3.30), South zone of the province (HR for South zone vs. Calgary zone: 1.85; 95% CI: 1.49-2.30), and higher comorbidity index (HR for ≥3 vs. 0: 2.66; 95% CI: 2.19-3.24). Although Kaplan-Meier method showed significant difference in OS according to diagnosis period, multivariable regression model showed that the period of diagnosis did not appear to impact OS (HR for diagnosis period 2004 to 2009 vs. 2014 to 2019: 1.04; 95% CI: 0.89-1.22).

CONCLUSIONS

Over the study period (2004 to 2019), patients diagnosed during later periods did not appear to experience better OS compared with patients diagnosed at an earlier time.

Skeletal muscle is prognostic in resected stage III malignant melanoma

BACKGROUND

Sarcopenia (low skeletal muscle index, SMI) and myosteatosis (low skeletal muscle radiodensity, SMD) have been associated with worse survival in cancer. This study evaluated associations of body composition with survival in patients with resected stage III melanoma.

METHODS

A retrospective review was performed of resected stage III melanoma patients in Alberta, Canada from 2007 to 2017. Preoperative CT scans were analyzed to determine SMI and SMD. Cohort-specific SMI and SMD cut-offs that optimally predicted overall survival (OS) were identified through stratification, in addition to testing cut-offs previously established in the literature. Overall (OS), melanoma-specific (MSS), and recurrence-free survival (RFS) were determined from date of surgery and analysed using multivariable Cox regressions with age, sex, BMI, stage subgroup, ECOG PS, and tumor location as covariates.

RESULTS

We included 330 patients in the final analysis. Mean age was 56 years and 62.4% of patients were male. At time of censoring 150 patients (45.6%) had died. Sarcopenia based on literature cut-offs was associated with decreased OS (HR 1.55, 95% CI 1.00-2.21, p = 0.016). Using cohort-specific cut-offs, sarcopenic patients also had significantly decreased OS (HR 1.87, 95% CI 1.27-2.76, p = 0.002). Myosteatosis defined using cohort-specific cut-offs predicted worse OS (HR 2.15, 95% CI 1.42-3.25, p < 0.001), MSS (HR 2.29, 95% CI 1.40-3.75, p = 0.001) and RFS (HR 1.52, 95% CI 1.02-2.27, p = 0.041). Increased BMI ( ≥ 25) and visceral fat index were not significantly associated with survival.

CONCLUSIONS

Sarcopenia and myosteatosis, defined using two sets of cut-offs, are associated with decreased OS and MSS in resected stage III melanoma.

CT-based assessment of body composition and skeletal muscle in melanoma: A systematic review

BACKGROUND/OBJECTIVES

Sarcopenia (low skeletal muscle index) and myosteatosis (low skeletal radiodensity) have been associated with poor outcomes in melanoma. This systematic review was performed to summarize and critically evaluate current literature surrounding body composition in melanoma.

METHODS

MEDLINE and Embase databases were searched for studies of melanoma patients with computed tomography (CT) based body composition analysis from 2000 to 2020. Outcomes of interest were survival, including overall survival (OS), progression-free survival (PFS), and disease-free survival (DFS), as well as treatment-related adverse events (AEs).

RESULTS

Nine studies of 914 patients were included in the final review. The majority of studies were of metastatic melanoma patients treated with immunotherapy. Studies demonstrated a variety of CT analysis techniques and cut-offs to define sarcopenia and myosteatosis. Associations of sarcopenia or myosteatosis with survival (OS, PFS, DFS) or risk of treatment-related AEs were conflicting. Multiple studies had low quality of evidence due to small sample sizes, use of non-validated CT measures, and lack of multivariable analyses.

CONCLUSIONS

Due to methodologic heterogeneity and low quality of evidence, impacts of CT-derived body composition parameters on outcomes in melanoma are unclear. Further research should be conducted to elucidate impacts of body composition in melanoma.

Case report: Proton pump inhibitor drug-related problem in pancreatic cancer patient unmasks pancreatic enzyme insufficiency

INTRODUCTION

Palliative care aims to improve the quality of life of patients with a life-limiting or life-threatening illness and is multifaceted involving comprehensive interdisciplinary assessments and interventions. Interdisciplinary palliative care in the setting of untreatable cancer diagnoses is of particular importance due to additional considerations that must be taken as patients are often undergoing palliative chemotherapy and/or radiation therapy. These patients' complexity warrants special considerations and attentiveness to drug-related problems.

CASE REPORT

The purpose of this case report is to highlight the importance of both complete and comprehensive medication histories in cancer care and the impact of proton pump inhibitors on pancreatic enzyme insufficiencies secondary to pancreatic cancers. This case involves a drug-related problem involving three medications that are commonly used in pancreatic cancer patients: pancreatic enzyme replacement therapy, a proton pump inhibitor, and a fluoroquinolone antibiotic. The patient presented in this case report is an 80-year-old man diagnosed with unresectable pancreatic cancer with a history of symptomatic gastroesophageal reflux disease managed with a proton pump inhibitor, specifically tablets of the 40 mg strength of pantoprazole magnesium taken orally once daily. During the patient's first of five 28-day cycles of palliative-intent chemotherapy with gemcitabine and nab-paclitaxel, the patient presented to the emergency department due to fever and, although not severely neutropenic, was prescribed amoxicillin/clavulanate and ciprofloxacin due to his advanced age. After reading a patient advisory on a ciprofloxacin patient information sheet that advised avoidance of concomitant administration of ciprofloxacin and magnesium, the patient self-discontinued his pantoprazole as it was a magnesium salt formulation. This discontinuation was followed by two weeks of persistent foul-smelling diarrhea, flatulence, and abdominal pain.

MANAGEMENT AND OUTCOME

The patient's healthcare team symptomatically managed the patient with oral and intravenous rehydration unaware of the cause of the symptoms. A trial of pancreatic enzyme replacement therapy was initiated; however, it was unsuccessful in resolving his symptoms. After further investigation and a more in-depth patient interview, it was discovered that the discontinued proton pump inhibitor was likely the cause of the patient's new symptoms and was subsequently re-initiated. Pancreatic enzyme replacement therapy in combination with re-initiation of pantoprazole therapy essentially resolved all symptoms.

DISCUSSION

Before his diagnosis of unresectable pancreatic cancer, the patient had been on proton pump inhibitor therapy for nearly a decade. He had significant atrophy of the pancreas and an undoubtedly decreased pancreatic enzyme and bicarbonate production; however, he did not experience foul-smelling diarrhea indicative of pancreatic enzyme insufficiency while he was on his proton pump inhibitor. We believe that with his proton pump inhibitor therapy, he was unknowingly being partially treated for his worsening pancreatic enzyme insufficiency, specifically the component related to his lack of bicarbonate production and secretion. His discontinuation of his proton pump inhibitor led to a decrease in gastric acid, small bowel, and normal intraduodenal pH, which resulted in any remaining pancreatic enzyme reserve to become non-functional, unmasking his pancreatic enzyme insufficiency. An initial empiric trial of pancreatic enzyme replacement therapy failed in the absence of a proton pump inhibitor; however, within days of restarting his proton pump inhibitor along with pancreatic enzyme replacement therapy, his gastrointestinal symptoms completely resolved. This is due to the decrease of gastric and intraduodenal acidity, which better enabled the function of pancreatic enzymes present in pancreatic enzyme replacement therapy.

An exploratory study of body composition as a predictor of dose-limiting toxicity in metastatic pancreatic cancer treated with gemcitabine plus nab-paclitaxel

BACKGROUND

Body composition is increasingly being studied as a method of predicting chemotherapy toxicity. Our study aimed to evaluate associations of body composition with treatment toxicity in a group of pancreatic cancer patients treated with gemcitabine plus nab-paclitaxel.

METHODS

A retrospective review was performed for all patients who received first-line gemcitabine plus nab-paclitaxel for metastatic pancreatic cancer at a northern Alberta cancer institute (Canada) from 2014 to 2017. Total lean body mass (LBM) was derived from measurements of muscle surface area at L3 on baseline computed tomography (CT) scans. Optimal stratification, or minimal p-value analysis, was used to assess for a threshold of nab-paclitaxel dose per LBM (mg/kg) associated with a higher risk of dose-limiting toxicity (DLT).

RESULTS

152 patients were included in the study, of whom 62 (40.8%) experienced DLT. nab-Paclitaxel dose/LBM ranged from 0.98 to 8.76 mg/kg. A threshold for nab-paclitaxel dose/LBM that optimally predicted risk of DLT was identified at 5.83 mg/kg. Above this cut-off, 18/31 (58.1%) patients experienced DLT, compared to 44/121 (36.4%) patients below (p = 0.028). Patients above this cut-off had a higher incidence of peripheral neuropathy compared to those below, though this was not statistically significant based on an adjusted p-value threshold (48.4 vs. 29.8% respectively, p = 0.050). Body mass index, body surface area, and absolute initial doses of nab-paclitaxel or gemcitabine did not significantly impact likelihood of DLT.

CONCLUSIONS

nab-Paclitaxel dose normalized to LBM, based on CT-derived measures of skeletal muscle, has potential to predict risk of chemotherapy toxicity. Chemotherapy dosing based on body composition, rather than conventional anthropometric measures, may be effective in reducing treatment toxicity.

Abstract 432: Sarcopenia predicts dose-limiting toxicity in metastatic pancreatic cancer treated with gemcitabine plus nab-paclitaxel

Introduction: Gemcitabine (GEM) plus nab-paclitaxel (nab) has been shown to improve overall survival (OS) compared to GEM monotherapy in patients with metastatic pancreatic cancer. However, GEM/nab is associated with increased toxicity. Our study evaluated whether sarcopenia increased the likelihood of chemotherapy toxicity in pancreatic cancer treated with GEM/nab.

Methods: A retrospective review was performed of all patients who received GEM/nab as first-line therapy for metastatic pancreatic cancer at a northern Alberta cancer institute (Canada) from 2014-2017. Patients were included if a computed tomography (CT) scan of the abdomen and pelvis was performed within 60 days of starting chemotherapy. Skeletal muscle surface area was measured at L3 on baseline CT scans and normalized for height to determine skeletal muscle index (SMI, cm2/m2). Dose-limiting toxicity (DLT) was defined as dose reduction or treatment discontinuation due to toxicity. Optimal stratification was used to establish sex-specific SMI cut-offs with DLT as an outcome.

Results: 152 patients were included in the study. 88 patients (57.8%) were male and median age was 66.5 years (range 34-95). 62 patients (40.8%) experienced DLT. SMI cut-offs were determined as &lt;48.0 cm2/m2 in males and &lt;39.55 cm2/m2 in females. Sarcopenia prevalence using these cut-offs was 54.6%. DLT incidence was significantly higher in sarcopenic versus non-sarcopenic patients (55.4 vs. 23.2% respectively, p&lt;0.001). In multivariate logistic regression accounting for advanced age (&gt;65), sex, BMI category, and performance status (PS), sarcopenia significantly increased the likelihood of DLT (OR 7.21, 95% CI 3.02-17.24, p&lt;0.001). Sarcopenia did not impact OS (HR 1.30, 95% CI 0.94-1.80, p=0.118) or progression-free survival (HR 0.66, 95% CI 0.42-1.03, p=0.071).

Conclusion: In pancreatic cancer treated with GEM/nab, sarcopenic patients are significantly more likely to experience DLT, independent of age, sex, BMI, and PS. These findings could have implications for reduced chemotherapy dosing in sarcopenic patients.

Citation Format: Susie Youn, Angela Chen, Vincent Ha, Carole Chambers, Dean T. Eurich, Michael McCall, Michael B. Sawyer. Sarcopenia predicts dose-limiting toxicity in metastatic pancreatic cancer treated with gemcitabine plus nab-paclitaxel [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2021; 2021 Apr 10-15 and May 17-21. Philadelphia (PA): AACR; Cancer Res 2021;81(13_Suppl):Abstract nr 432.

Phase I study of H3B-6527 in hepatocellular carcinoma (HCC) or intrahepatic cholangiocarcinoma (ICC)

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Background: Evidence suggests that hyperactivated fibroblast growth factor 4 (FGFR4) signaling pathway leads to enhanced tumor growth. Targeting FGFR4 may have therapeutic benefit in tumors with altered FGF19 signaling. A phase I study (NCT02834780) was undertaken to assess H3B-6527, a highly selective covalent FGFR4 inhibitor, in patients with HCC/ICC. Methods: Adults with advanced HCC/ICC, ECOG PS 0-1, well compensated liver function, who progressed after > one prior therapy, received H3B-6527 po daily (QD) or twice-daily (bid) on a 21-day cycle following a 3+3 design. Doses ranged from 300-2000mg QD or 500-700mg BID. Patients in dose escalation were treated regardless of FGF19 status. Patients in expansion had FGF19+ tumors by mRNA testing. Adverse events (AEs), and pharmacokinetics (PK) were assessed. Response was determined by RECIST 1.1/mRECIST imaging every 6 weeks. Results: Study enrollment is complete at 128 patients. Ninety HCC patients were treated (QD = 48, bid = 42). ICC enrollment was suspended after 38 patients due to limited efficacy. No dose-limiting toxicities were seen and no grade 4-5 treatment related AEs have been observed. Recommended Phase II dose for H3B-6527 is 1000mg QD based upon safety, efficacy, and PK data. Grade 3 TEAEs have occurred in 12.5% of patients on QD dosing. Treatment related TEAEs were seen in 62.5% of patients on the QD schedule, with diarrhea (45.8%), fatigue (12.5%), and nausea (12.5%) most frequent. Drug discontinuation due to AEs for QD dosing was 8.3%. Interim data analysis shows that, for HCC patients with >2 prior lines of therapy treated on QD schedule, overall survival was 10.6m, progression-free survival 4.1m, overall response rate 16.7% (all partial responses), and clinical benefit rate 45.8% (responders + durable stable disease >17 weeks). H3B-6527 Cmax and AUC were lower at 300 mg dose but then similar across 500–2000 mg doses. Following oral administration of 1000 mg fasted, H3B-6527 plasma concentration reached peak at a Tmax of ̃2-3 hours and then decayed exponentially, with terminal half-life of ̃4-5 hours. There was no accumulation following QD dose. Dosing with food did not meaningfully change H3B-6527 plasma exposure. Conclusions: H3B-6527 was well tolerated and demonstrated a favorable toxicity and safety profile and encouraging clinical activity in heavily pretreated HCC patients. Final trial results will be presented at conference. Clinical trial information: NCT02834780.

Uridine Glucuronosyltransferase 2B7 Polymorphism-Based Pharmacogenetic Dosing of Epirubicin in FEC Chemotherapy for Early-Stage Breast Cancer

BACKGROUND

Epirubicin is metabolized by uridine glucuronosyltransferase 2B7 (UGT2B7). Patients homozygous for the minor allele (CC) in the UGT2B7 -161 promoter polymorphism have lower clearance and significantly higher rates of leukopenia compared to wild-type homozygote (TT) or heterozygote (CT) patients. This study was designed to determine if TT and CT genotype patients could tolerate a higher epirubicin dose compared to CC genotype patients.

PATIENTS AND METHODS

We studied women with histologically confirmed non-metastatic, invasive breast cancer who were scheduled to receive at least three cycles of FE₁₀₀C in the (neo)adjuvant setting. Patients received standard-dose FE₁₀₀C during the first 21-day cycle. Based on genotype, the epirubicin dose was escalated in the second and third cycles to 115 and 130 mg/m² or to 120 and 140 mg/m² for CT and TT genotype patients, respectively. The main outcome measurements were myelosuppression and dose-limiting toxicity. These were analyzed for relationships with the three genotypes.

RESULTS

Forty-five patients were enrolled (10 CC, 21 CT, and 14 TT genotypes) and received 100 mg/m² of epirubicin in the first cycle. Twelve and 10 TT patients were dose escalated at the second and third cycles, respectively; 16 CT patients were dose escalated at the second and third cycles. Leukopenia, but not febrile neutropenia, was genotype and dose dependent and increased in patients with CT and TT genotypes as their dose was increased. However, the third-cycle leukopenia rates were comparable to patients with the CC genotype receiving standard-dose epirubicin.

CONCLUSION

Pharmacogenetically guided epirubicin dosing is well tolerated and allowed dose escalation without increased toxicity.

Myosteatosis is prognostic in metastatic melanoma treated with nivolumab

BACKGROUND

While immunotherapy agents have improved outcomes in metastatic melanoma (MM), predictive biomarkers in these patients are lacking. Parameters identified from body composition analysis, such as low SMD (also termed myosteatosis), may prognosticate MM patients on immunotherapy.

METHODS

In this retrospective study, 44 MM patients received nivolumab, either as monotherapy or in combination with ipilimumab. Pre-treatment computed tomography (CT) scans were analyzed to determine skeletal muscle density (SMD) in Hounsfield units (HU) and muscle surface area (MSA) in cm² at L3. MSA was used to determine nivolumab dosing in mg/cm².

RESULTS

Low SMD was associated with worse overall survival (OS) by log rank test (median 12.03 vs. 34.96 months, p = 0.001) and in multivariate analysis when accounting for age, sex, performance status, and number of prior lines of therapy (HR 4.40, 95% CI 1.44-13.42, p = 0.009). Lower nivolumab dosing by MSA was significantly associated with improved OS (median 42.9 vs. 12.3 months, p < 0.001). This association remained significant in multivariate analysis with age, sex, performance status, and number of prior lines of therapy (HR 0.05, 95% CI 0.01-0.30, p = 0.001). Neither SMD nor higher nivolumab dose per MSA were associated with increased incidence of treatment toxicity.

CONCLUSIONS

Low SMD is prognostic in MM treated with nivolumab immunotherapy. Presence of myosteatosis or higher nivolumab dose based on body composition did not predict treatment toxicity.

Protein Recommendation to Increase Muscle (PRIMe): Study protocol for a randomized controlled pilot trial investigating the feasibility of a high protein diet to halt loss of muscle mass in patients with colorectal cancer

BACKGROUND

Severe muscle mass (MM) loss is a defining feature of cancer observed across all types and stages of disease and is an independent predictor of poor clinical outcomes including higher incidences of chemotherapy toxicity and decreased survival. Protein is essential to build MM, yet the optimal amount for preventing or treating muscle loss in patients with cancer remains undefined.

METHODS

The Protein Recommendation to Increase Muscle (PRIMe) study is a single-center, two-armed, parallel, randomized, controlled pilot trial that assesses the feasibility of utilizing a high protein (HP) diet to positively impact clinical outcomes in people undergoing chemotherapy to treat colorectal cancer. Forty patients with newly diagnosed stage II-IV colorectal cancer who are scheduled to receive chemotherapy will be included. Participants are randomly assigned to a HP or normal protein (NP) diet for twelve weeks. The HP and NP groups receive nutrition recommendations to achieve 2.0 g of protein per kilogram of body weight per day (g∙kg^-1∙d^-1) and 1.0 g⋅kg^-1⋅d^-1, respectively. These values refer to the upper and lower recommended range of protein intake for people with cancer. Energy recommendations are based on measured energy expenditure. Assessments are completed within two weeks of starting chemotherapy (baseline), at week 6, and at week 12. Changes to skeletal MM, physical function, anthropometrics, body composition, muscle strength, physical activity, energy metabolism, metabolic markers, nutritional status, quality of life, readiness to change and psychosocial determinants of behavioural change are assessed between the HP and NP groups. Feasibility of the nutritional intervention is assessed by change in MM as a surrogate marker.

CONCLUSIONS

This evidence-based study investigates the feasibility of increasing protein intake following a diagnosis of cancer on clinical outcomes during treatment for colorectal cancer. This study will inform larger trials assessing the impact of increasing protein intake in cancer to determine their importance and integration into standard clinical care for people with cancer.

Tyrosine Kinase Inhibitors Reduce Glucose Uptake by Binding to an Exofacial Site on hGLUT-1: Influence on 18 F-FDG PET Uptake

Positron emission tomography (PET) using 2‐deoxy‐2‐[¹⁸F]fluoro‐d‐glucose ([¹⁸F]FDG), a marker of energy metabolism and cell proliferation, is routinely used in the clinic to assess patient response to chemotherapy and to monitor tumor growth. Treatment with some tyrosine kinase inhibitors (TKIs) causes changes in blood glucose levels in both nondiabetic and diabetic patients. We evaluated the interaction of several classes of TKIs with human glucose transporter‐1 (hGLUT‐1) in FaDu and GIST‐1 cells by measuring [³H]2‐deoxy‐d‐glucose ([³H]2‐DG) and [³H]FDG uptake. Uptake of both was inhibited to varying extents by the TKIs, and representative TKIs from each class showed competitive inhibition of [³H]2‐DG uptake. In GIST‐1 cells, [³H]FDG uptake inhibition by temsirolimus and nilotinib was irreversible, whereas inhibition by imatinib, gefitinib, and pazopanib was reversible. Molecular modeling studies showed that TKIs form multiple hydrogen bonds with polar residues of the sugar binding site (i.e., Q161, Q282, Q283, N288, N317, and W388), and van der Waals interactions with the H‐pocket site. Our results showed interaction of TKIs with amino acid residues at the glucose binding site to inhibit glucose uptake by hGLUT‐1. We hypothesize that inhibition of hGLUT‐1 by TKIs could alter glucose levels in patients treated with TKIs, leading to hypoglycemia and fatigue, although further studies are required to evaluate roles of other SLC2 and SLC5 members. In addition, TKIs could affect tumor [¹⁸F]FDG uptake, increasingly used as a marker of tumor response. The hGLUT‐1 inhibition by TKIs may have implications for routine [¹⁸F]FDG‐PET monitoring of tumor response in patients.

Plasma levels of platinum-induced fatty acid [16:4n-3] do not affect response to platinum-based chemotherapy: A pilot study in non-small cell lung cancer patients

BACKGROUND & AIMS

Pre-clinical studies suggest that 16:4(n-3) in purified form or as a component of fish oil might induce platinum-based chemotherapy resistance. Our aim was to determine plasma total and free 16:4(n-3) before and during platinum-based chemotherapy in non-small cell lung cancer (NSCLC) patients supplemented with fish oil or provided standard care, and to explore relationships between plasma 16:4(n-3) levels and tumor response to treatment.

METHODS

In a retrospective, secondary data analysis of a prior clinical trial, plasma from patients with NSCLC (n = 21) who underwent platinum-based chemotherapy and were assigned to 2.2 g/day of eicosapentaenoic (EPA) plus 1.1 g DHA/day as fish oil (FO; n = 12) or received no intervention (standard care; SC; n = 9). Plasma 16:4(n-3) was quantified as free and esterified (total) fatty acid using HPLC-MS/MS. Plasma 16:4(n-3) levels were evaluated over time in relation to fish oil supplementation and response to platinum-based therapy, and compared with a group of healthy subjects (REF; n = 11).

RESULTS

Plasma 16:4(n-3) was detected in all samples. The percentage change/day in plasma esterified (total) 16:4(n-3) was higher for FO versus SC group (2.7 versus -1.8%/d, U = 20, p = 0.02), but change in plasma free 16:4(n-3) was not different between FO and SC. Median plasma free and esterified 16:4(n-3) were similar between responders and non-responders to platinum-based chemotherapy. Total and free plasma 16:4(n-3) fatty acids were similar between NSCLC patients and REF (NSCLC vs REF: total 16:4(n-3): 122.9 vs. 95.2 nM and free 16:4(n-3) 23.9 vs. 27.6 nM).

CONCLUSIONS

This first of its kind study that evaluated plasma 16:4(n-3) in NSCLC patients showed that 16:4 (n-3) was elevated during FO supplementation, independent of fish oil supplementation or platinum-based chemotherapy.

First Case of Regression of Carcinoid Heart Disease on Serial Transthoracic Echocardiograms following Octreotide Monotherapy in a Patient with Metastatic Pancreatic Neuroendocrine Tumor

Well-differentiated neuroendocrine tumors (NETs) arising in the gastrointestinal (GI) tract and pancreas are relatively rare; however, the annual incidence has been increasing. Carcinoid syndrome (CS) is a constellation of symptoms that occur when a GI NET metastasizes to the liver and releases high levels of vasoactive substances into the systemic circulation. CS occurs in 19% of NETs patients at diagnosis and is associated with shorter survival. Carcinoid heart disease (CHD) occurs in over 50% of patients with CS and is associated with poor long-term prognosis. NET-induced valvular fibrosis is a significant cause of mortality and morbidity in these patients. Somatostatin analogs relieve CS symptoms, but they have never been shown to reverse CHD progression or improve overall survival. Surgical therapy for right-sided valve disease is associated with improved symptoms and quality of life and possibly improved survival, despite relatively high morbidity and mortality associated with cardiac intervention. A 65-year-old woman with a metastatic pancreatic NET had typical signs and symptoms of CS. She presented in congestive heart failure and was found to have severe tricuspid regurgitation with characteristic features of CHD on transthoracic echocardiogram (TTE). Following octreotide monotherapy, serial TTEs demonstrated regression of tricuspid valve involvement. The patient improved clinically and remained asymptomatic on subsequent visits. This is the first case of CHD regression with medical therapy supported by serial TTEs. Developing a deeper understanding of cases like this will help us unlock new intervention targets and strategies for treatments in the future.

Tolerability of pemetrexed and oxaliplatin in the treatment of stage III colon cancer during raltitrexed shortage

Colorectal cancer is one of the most common malignancies diagnosed in Canada. Currently, adjuvant colorectal cancer treatment primarily includes chemotherapeutic regimens such as FOLFOX6 (5-fluorouracil, leucovorin, oxaliplatin) or CAPOX (capecitabine, oxaliplatin), as well as alternative regimens such as TOMOX (raltitrexed, oxaliplatin). However, the prevalence of drug shortages in today's society may make these preferred regimens inaccessible. The purpose of this case report is to highlight the tolerability of an alternative adjuvant regimen (pemetrexed plus oxaliplatin) that has undergone both phase I and II clinical trials for the treatment of colorectal cancer. The patient presented in this case report is a 57-year-old female diagnosed with Stage III colon cancer. This patient received seven cycles of pemetrexed plus oxaliplatin and experienced several adverse events, with the majority of them being mild in nature including fatigue and cold dysesthesia. However, the patient also experienced progressive neuropathy which required a dose reduction and subsequent discontinuation of oxaliplatin. Overall, pemetrexed and oxaliplatin's tolerability seems comparable to other regimens used to treat colorectal cancer and could potentially be an option to consider in the future for alternative treatment of colorectal cancer pending further trials.

Body composition is prognostic and predictive of ipilimumab activity in metastatic melanoma

BACKGROUND

Body composition is minimally investigated in an immunotherapy era. Specific body composition signals such as myosteatosis may reflect aspects of patients' immunology and thereby their ability to respond to immunotherapies. Ipilimumab is a key checkpoint inhibitor in metastatic melanoma. As an antibody, it may also be more accurately dosed using body composition parameters rather than weight alone. This retrospective study aimed to investigate body composition-based dosing and outcomes.

METHODS

Pretreatment computed tomography images from metastatic melanoma, ipilimumab-treated patients from 2009 to 2014 were used to measure myosteatosis [skeletal muscle radiographic density or SMD, in Hounsfield units (HU)] and surface area (cm² ) as previously described. Cut point analysis determined whether a level of ipilimumab dose and myosteatosis demonstrated differences in progression-free (PFS) and overall survival (OS). Secondary endpoints included objective response rates and toxicities.

RESULTS

Of 121 identified, 97 patients were evaluable. Baseline demographics included 56 years median age, 60% male participants, and 23.7% with BRAF mutations. SMD analysis identified cut-offs of SMD < 42 in those with BMI < 25 kg/m² and <20 HU in those with BMI ≥ 25 kg/m² , respectively. Low SMD patients had poorer median PFS [2.4 vs. 2.7 months, hazard ratio (HR) 1.76, P = 0.008] and OS (5.4 vs. 17.5 months, HR 2.47, P = 0.001), which remained significant in multivariate modelling. High SMD patients had more immune-related adverse events, better objective response rates (17.9 vs. 3.3%, P = 0.051), and lower baseline neutrophil-to-lymphocyte ratio (21 vs. 39%, P = 0.049). Separately, patients receiving <2.03 mg/cm² had improved median PFS (3.0 vs. 2.6 months, HR 1.88, P = 0.02) and OS (14.9 vs. 5.7 months, HR 1.98, P = 0.01).

CONCLUSIONS

Low SMD and receiving >2.03 mg/cm² are prognostic of poorer melanoma outcomes post ipilimumab. SMD may identify patients with flawed immunology and predict who may better respond to such therapy. Ipilimumab dosing by skeletal muscle index stands in contrast to weight-based dosing and may demonstrate a more accurate method of antibody dosing.

A phase Ib study of oral Chk1 inhibitor LY2880070 in combination with gemcitabine in patients with advanced or metastatic cancer

3581

Background: LY2880070 (LY) is an oral, selective competitive inhibitor of checkpoint kinase 1 (Chk1). Chk1 inhibitors are known to increase the anti-tumor efficacy of agents such as gemcitabine (GEM), which induce replication stress. Synergy between these two agents has been applied to the clinical setting. Methods: This two-part, open-label multi-center study explores the safety, pharmacokinetics (PK), and anti-tumor activity of LY in patients with advanced or metastatic cancers. The primary objective of this study was to determine the maximum tolerated dose (MTD) for multiple escalating oral doses of LY in combination with GEM. Secondary objectives were to: 1) Characterize the dose-limiting toxicities (DLTs) and overall safety profile for LY; 2) Evaluate the PK of LY; and 3) Evaluate the anti-tumor activity of LY. Patients received LY in a variety of different dose regimens, in combination with GEM (50 to 800 mg/m2) on days 1, 8, and 15 (optional) of a 21-day cycle. Results: The combination of LY with GEM required lower doses of both LY (vs 200 mg BID monotherapy RP2D dose) and GEM (vs approved doses). The dose levels explored ranged from LY:GEM of 10 mg QD:800 mg/m2 to 50 mg BID:100 mg/m2. BID dosing of LY was implemented in order to maximize the total daily dose and avoid the adverse events that appeared to correlate with Cmax. Treatment-emergent adverse events in > 40% of patients included vomiting, nausea, and fatigue. DLTs included reduced platelet count (Gr2), fatigue (Gr3), diarrhea (Gr3), and thrombocytopenia (x2, Gr2). The t1/2 of LY was ~ 5 h, and was not significantly affected by combination with GEM. Two patients had a best overall response of SD for a duration of ≥ 6 cycles, and a confirmed PR was observed in an ovarian cancer patient who had failed multiple regimens. Conclusions: LY was tolerated in combination with lower dose GEM. The toxicity profile can be modulated by changing the dosing frequency from QD to BID while administering the same daily dose. LY may be good candidate for combination therapy with DNA damaging agents. Clinical trial information: NCT02632448 .

PRESS timings for resolving 13 C4 -glutamate 1 H signal at 9.4 T: Demonstration in rat with uniformly labelled 13 C-glucose

MRS of ¹³ C₄ -labelled glutamate (¹³ C₄ -Glu) during an infusion of a carbon-13 (¹³ C)-labelled substrate, such as uniformly labelled glucose ([U-¹³ C₆ ]-Glc), provides a measure of Glc metabolism. The presented work provides a single-shot indirect ¹³ C detection technique to quantify the approximately 2.51 ppm ¹³ C₄ -Glu satellite proton (¹ H) peak at 9.4 T. The methodology is an optimized point-resolved spectroscopy (PRESS) sequence that minimizes signal contamination from the strongly coupled protons of N-acetylaspartate (NAA), which resonate at approximately 2.49 ppm. J-coupling evolution of protons was characterized numerically and verified experimentally. A (TE₁ , TE₂ ) combination of (20 ms, 106 ms) was found to be suitable for minimizing NAA signal in the 2.51 ppm ¹ H ¹³ C₄ -Glu spectral region, while retaining the ¹³ C₄ -Glu ¹ H satellite peak. The efficacy of the technique was verified on phantom solutions and on two rat brains in vivo during an infusion of [U-¹³ C₆ ]-Glc. LCModel was employed for analysis of the in vivo spectra to quantify the 2.51 ppm ¹ H ¹³ C₄ -Glu signal to obtain Glu C4 fractional enrichment time courses during the infusions. Cramér-Rao lower bounds of about 8% were obtained for the 2.51 ppm ¹³ C₄ -Glu ¹ H satellite peak with the optimal TE combination.

Prolonged Response to Regorafenib in a Patient with Iodine Refractory Thyroid Cancer

Thyroid cancer is the most common type of endocrine malignancy. Cornerstones of thyroid cancer treatment include surgery, radioactive iodine ablation, and thyroid stimulating hormone suppression. The National Comprehensive Cancer Network guidelines recommend two tyrosine kinase inhibitors for thyroid cancer patients who are non-responsive to iodine: sorafenib and lenvatinib. Another oral kinase inhibitor, regorafenib, is not considered standard of care treatment for differentiated thyroid cancer. The chemical structures of regorafenib and sorafenib differ by a single fluorine atom. Given the significant improvement in progression-free survival (PFS) of sorafenib compared to placebo demonstrated in the phase 3 DECISION trial, we report on a patient with iodine-refractory follicular thyroid cancer treated with regorafenib as part of a phase 1 clinical trial. A 75 year old woman was diagnosed with follicular thyroid carcinoma in 2006 and initiated on treatment with regorafenib in 2011. She has completed 76 cycles with stable disease and pulmonary metastases 34% smaller than baseline.

Total energy expenditure in patients with colorectal cancer: associations with body composition, physical activity, and energy recommendations

BACKGROUND

Total energy expenditure (TEE) data in patients with early-stage cancer are scarce, precluding an understanding of energy requirements.

OBJECTIVE

The objective was to cross-sectionally characterize TEE in patients with colorectal cancer (CRC) and to compare measured TEE with energy recommendations. It was hypothesized that TEE would differ according to body mass, body composition, and physical activity level (PAL) and current energy recommendations would have poor individual-level accuracy.

METHODS

Patients with newly diagnosed CRC had resting energy expenditure (REE) measured by indirect calorimetry and TEE by doubly labeled water. Hypermetabolism was defined as REE > 110% of that predicted from the Mifflin St.-Jeor equation. Body composition was assessed via DXA. Physical activity was determined as the ratio of TEE to REE (TEE:REE) (PAL) and residual activity energy expenditure (RAEE). TEE was compared with energy recommendations of 25-30 kcal/d and Dietary Reference Intakes (DRIs) using Bland-Altman analyses. Patients were stratified according to median BMI, PAL, and sex-specific ratio of fat mass (FM) to fat-free mass (FFM).

RESULTS

Twenty-one patients (M:F 14:7; mean ± SD BMI: 28.3 ± 4.9 kg/m2, age: 57 ± 12 y) were included. Most (n = 20) had stage II-III disease; 1 had stage IV. Approximately half (n = 11) were hypermetabolic; TEE was not different in those with hypermetabolism and REE as a percentage of predicted was not correlated with TEE. Mean ± SD TEE was 2473 ± 499 kcal/d (range: 1562-3622 kcal/d), or 29.7 ± 6.3 kcal/kg body weight (range: 20.4-48.5 kcal/kg body weight). Mean ± SD PAL was 1.43 ± 0.27. The energy recommendation of 25 kcal/kg underestimated TEE (-12.6% ± 16.5%, P = 0.002); all energy recommendations had wide limits of agreement (the smallest was DRI with measured PAL: -21.2% to 29.3%). Patients with higher BMI and FM:FFM had higher bias using kilocalories per kilogram recommendations; bias from several recommendations was frequently lower (i.e. underestimation) in patients with higher PAL and RAEE.

CONCLUSIONS

TEE variability was not reflected in energy recommendations and error was related to body weight, body composition, and physical activity. This trial was registered at clinicaltrials.gov as NCT03131921.

Accuracy of Resting Energy Expenditure Predictive Equations in Patients With Cancer

BACKGROUND

Our purpose was to assess the accuracy of resting energy expenditure (REE) equations in patients with newly diagnosed stage I-IV non-small cell lung, rectal, colon, renal, or pancreatic cancer.

METHODS

In this cross-sectional study, REE was measured using indirect calorimetry and compared with 23 equations. Agreement between measured and predicted REE was assessed via paired t-tests, Bland-Altman analysis, and percent of estimations ≤ 10% of measured values. Accuracy was measured among subgroups of body mass index (BMI), stage (I-III vs IV), and cancer type (lung, rectal, and colon) categories. Fat mass (FM) and fat-free mass (FFM) were assessed using dual x-ray absorptiometry.

RESULTS

Among 125 patients, most had lung, colon, or rectal cancer (92%, BMI: 27.5 ± 5.6 kg/m² , age: 61 ± 11 years, REE: 1629 ± 321 kcal/d). Thirteen (56.5%) equations yielded REE values different than measured (P < 0.05). Limits of agreement were wide for all equations, with Mifflin-St. Jeor equation having the smallest limits of agreement, -21.7% to 11.3% (-394 to 203 kcal/d). Equations with FFM were not more accurate except for one equation (Huang with body composition; bias, limits of agreement: -0.3 ± 11.3% vs without body composition: 2.3 ± 10.1%, P < 0.001). Bias in body composition equations was consistently positively correlated with age and frequently negatively correlated with FM. Bias and limits of agreement were similar among subgroups of patients.

CONCLUSION

REE cannot be accurately predicted on an individual level, and bias relates to age and FM.

Profiling Determinants of Resting Energy Expenditure in Colorectal Cancer

Background: Understanding resting energy expenditure (REE) is important for determining energy requirements; REE might be altered in individuals with cancer. The objective of this study was to characterize determinants of REE in patients with stages II-IV colorectal cancer (CRC).Methods: REE was measured via indirect calorimetry in patients with newly diagnosed CRC. Computerized tomography images from medical records ascertained skeletal muscle and total adipose tissue cross-sectional areas, which were then transformed to lean soft tissue (LST) and fat mass (FM) values (in kg). Linear regression assessed determinants of REE.Results: 86 patients were included (n = 55, 64.0% male; 60 ± 12 years old; median body mass index: 27.6, interquartile range: 24.3-31.2 kg/m²), with most (n = 40) having stage III disease. Age, sex, and weight were significant predictors of REE [R² = 0.829, standard error of the estimate (SEE): 128 kcal/day, P < 0.001]. Replacing weight with LST and FM yielded a similar model, with age, sex, LST, and FM predictive of REE (R² = 0.820, SEE: 129 kcal/day, p < 0.001).Conclusion: Age, sex, weight, LST, and FM were the main contributors to REE. Further investigation of REE changes over time and its relationship to total energy expenditure, dietary intake, and clinical outcomes should be explored.

A phase I study of H3B-6527 in hepatocellular carcinoma (HCC) or intrahepatic cholangiocarcinoma (ICC) patients (pts)

4095

Background: FGF19 overexpression is hypothesized to hyperactivate FGFR4 and its downstream signaling pathway leading to enhanced tumor growth in HCC/ICC. Targeting FGFR4 may have therapeutic benefit in HCC/ICC with altered FGF19 signaling. A phase 1 study (NCT02834780) was initiated to assess H3B-6527, an investigational highly selective covalent FGFR4 inhibitor. Methods: Adult pts with advanced HCC or ICC, ECOG PS 0-1, well compensated liver function, and who progressed after at least one prior therapy, were administered H3B-6527 orally QD (once daily) on a 21-day cycle following a 3+3 design. Patients in the dose escalation phase were treated regardless of FGF19 status. Adverse events (AEs), pharmacokinetics (PK), and pharmacodynamics (PD) were assessed. Response was determined by RECIST 1.1 or modified RECIST every 6 weeks. Results: As of 06-Jan-2019, 37 pts have been treated with H3B-6527 at doses of 300 to 1400 mg QD (23 pts in escalation; 14 in expansion). In dose escalation, a total of 17 patients with HCC, Child-Pugh A received prior systemic therapy including 100% with prior TKI and 35% with prior IO. 12% had hepatitis B virus and 47% had hepatitis C virus. H3B-6527 plasma levels increased with dose from 300 to 1000 mg QD and plateaued. H3B-6527 was rapidly absorbed with a tmax of ~2-3 h and showed a terminal half-life of ~4-5 h, following administration of 1000 mg (fasted). No dose-limiting toxicities or ≥ Grade 3 treatment-related AEs (TRAE) have been observed in escalation. Most common TRAEs (≥ 10%) were diarrhea, nausea, and vomiting. Based on safety, PK, and PD, 1000 mg QD was the recommended phase 2 dose. Durable stable disease and partial responses (PR) have been observed on the once daily fasted schedule; 2 of 17 pts with HCC achieved PRs and an additional 7 with stable disease were on treatment for ≥ 5 months. Conclusions: H3B-6527 is well tolerated and demonstrates early signs of clinical activity. Dose expansion on QD schedule and exploration of BID (twice daily) schedule is ongoing. Clinical trial information: NCT02834780.

A dose-finding study of the SMAC mimetic Debio 1143 when given in combination with avelumab to patients with advanced solid malignancies

2599

Background: Second mitochondria-derived activator of caspase (SMAC) mimetics regulate apoptosis and modulate NFκB signaling which drives the expression of genes involved in immune and inflammatory responses. In patient (pt) tumors, Debio 1143 increased PD-1/PD-L1 expression and tumor infiltrating lymphocytes. In pre-clinical models, it synergizes in vitro and in vivo with PD1/PD-L1 checkpoint inhibitors (CPIs). Methods: In a phase I study, using a mCRM model, avelumab (10 mg/kg i.v. on D1&15 q4w) was combined with escalating doses of Debio 1143 (100 mg/d to 250 mg/d orally, D1-10 & D15-24 q4w) to define the RP2D. Consenting adult pts with advanced solid tumors, normal organ function, and PS-ECOG = 0-1 were eligible provided none received prior CPI. Dose-limiting toxicities (DLTs), efficacy, safety, PK, PD and biomarkers were assessed. Results: As of DEC’18, 16 pts were treated; M/F: 8/8; ECOG = 0 in 6 (38%); median age = 58 (28-79); 5 pts had NSCLC, 2 MPM, 2 ovarian and 7 had other tumors (n = 1 each). Common AEs were: nausea (69%); fatigue (62%); vomiting (50%); cough, dyspnea, myalgia (44% each); diarrhea, anorexia (38% each); pruritus and constipation (31% each). These were generally grade 1-2, occasionally grade 3. One pt had a DLT at 250 mg/d dose: a grade 3 AST/ALT increase. No treatment-related AEs grade 4 or higher occurred. No dose-relationships for laboratory abnormalities were observed, except for ALT/AST increases, which at 200 mg/d were all grade 1 and asymptomatic. Maximal tolerated dose was not reached and there were no dose reductions. In 15 evaluable pts, 1 PR (NSCLC) and 5 SD (RECIST v1.1) were observed. Tumor shrinkage > 15% was seen in 2 other NSCLC pts. PK showed high interpatient variability and dose-proportional increase. TNFα and IFNγ peaked in plasma following Debio 1143 dose on D1 after 8 hrs, and on D17/22, in a dose-proportional manner. Four pts developed anti-avelumab antibodies. Conclusions: Debio 1143 at 200 mg/d can be safely combined with avelumab. Toxicity was predictable and mild. Clinical activity was observed in NSCLC pts. PK was linear; no drug interaction was suspected. PD and biomarker analysis is ongoing. Expansion at this RP2D is ongoing in NSCLC. Clinical trial information: NCT03270176.

Nivolumab (NIVO) + low-dose ipilimumab (IPI) in previously treated patients (pts) with microsatellite instability-high/mismatch repair-deficient (MSI-H/dMMR) metastatic colorectal cancer (mCRC): Long-term follow-up

635

Background: In the phase II CheckMate-142 trial, NIVO + low-dose IPI (1 mg/kg) provided meaningful clinical benefit in previously treated MSI-H/dMMR mCRC pts after a median follow-up of 13.4 mo. Here, we present long-term follow-up (median 25.4 mo) of these pts. Methods: Pts received NIVO 3 mg/kg + low-dose IPI Q3W (4 doses) followed by NIVO 3 mg/kg Q2W until disease progression. Primary endpoint was investigator (INV)-assessed objective response rate (ORR; RECIST v1.1). Results: Of 119 treated pts, 76% had ≥ 2 prior lines of therapy. ORR and disease control rates (DCR) were 58 and 81%, respectively (Table). Complete response (CR) rate increased with long-term follow-up from 3 (13.4 mo) to 6% (25.4 mo). Median duration of response (DOR) was not reached, with 68% of responses ongoing at data cutoff. At 24 mo, progression-free survival (PFS) and overall survival (OS) rates were 60 and 74%, respectively; OS rates were 96, 56, and 29% in pts with CR or partial response (PR), stable disease (SD), and progressive disease (PD), respectively. Grade 3–4 treatment-related adverse events (TRAEs) occurred in 31% of pts; 10% (grade 3–4) and 13% (any grade) of pts had TRAEs leading to discontinuation. Conclusions: Long-term follow-up with NIVO + low-dose IPI provides durable clinical benefit with deepening of response and a manageable safety profile with no new safety signals, demonstrating long-term benefit of NIVO + low-dose IPI for previously treated pts with MSI-H/dMMR mCRC. Clinical trial information: NCT02060188. [Table: see text]

Assessment of Computed Tomography (CT)-Defined Muscle and Adipose Tissue Features in Relation to Short-Term Outcomes After Elective Surgery for Colorectal Cancer: A Multicenter Approach

BACKGROUND

Sarcopenia, visceral obesity (VO), and reduced muscle radiodensity (myosteatosis) are suggested risk factors for postoperative morbidity in colorectal cancer (CRC), but usually are not concurrently assessed. Published thresholds used to define these features are not CRC-specific and are defined in relation to mortality, not postoperative outcomes. This study aimed to evaluate body composition in relation to length of hospital stay (LOS) and postoperative outcomes.

METHODS

Pre-surgical computed tomography (CT) images were assessed for total area and radiodensity of skeletal muscle and visceral adipose tissue in a pooled Canadian and UK cohort (n = 2100). Sex- and age-specific values for these features were calculated. For 1139 of 2100 patients, LOS data were available, and sex- and age-specific thresholds for sarcopenia, myosteatosis, and VO were defined on the basis of LOS. Association of CT-defined features with LOS and readmissions was explored using negative binomial and logistic regression models, respectively.

RESULTS

In the multivariable analysis, the predictors of LOS (P < 0.001) were age, surgical approach, major complications (incidence rate ratio [IRR] 2.42; 95% confidence interval [CI] 2.18-2.68), study cohort, and three body composition profiles characterized by myosteatosis combined with either sarcopenia (IRR, 1.27; 95% CI 1.12-1.43) or VO (IRR, 1.25; 95% CI 1.10-1.42), and myosteatosis combined with both sarcopenia and VO (IRR, 1.58; 95% CI 1.29-1.93). In the multivariable analysis, risk of readmission was associated with VO alone (odds ratio [OR] 2.66; 95% CI 1.18-6.00); P = 0.018), VO combined with myosteatosis (OR, 2.72; 95% CI 1.36-5.46; P = 0.005), or VO combined with myosteatosis and sarcopenia (OR, 2.98; 95% CI 1.06-5.46; P = 0.038). Importantly, the effect of body composition profiles on LOS and readmission was independent of major complications.

CONCLUSION

The findings showed that CT-defined multidimensional body habitus is independently associated with LOS and hospital readmission.

Multitargeted kinase inhibitors imatinib, sorafenib and sunitinib perturb energy metabolism and cause cytotoxicity to cultured C2C12 skeletal muscle derived myotubes

Tyrosine kinase inhibitors (TKIs) have advanced cancer treatment and prognosis but have also resulted in adverse effects such as fatigue, diarrhea, hypothyroidism, and other toxicities. We investigated TKI effects on skeletal muscle as a possible explanation of TKI induced fatigue. Changes in mitochondrial function due to inhibition of oxidative phosphorylation complexes, generation of superoxides, and inhibition of key transporters involved in uptake of glucose and/or nucleosides may result in alteration of energy metabolism and/or mitochondrial function. We investigated effects of imatinib, sorafenib and sunitinib on these processes in cultured C2C12 murine skeletal muscle cells. Imatinib, sorafenib and sunitinib were cytotoxic to C2C12 cells with IC₅₀ values of 20, 8 and 8 µM, respectively. Imatinib stimulated glucose uptake and inhibited complex V activity by 35% at 50 µM. Sorafenib inhibited complex II/III and V with IC₅₀ values of 32 and 28 µM, respectively. Sorafenib caused activation of caspase 3/7 and depolarization of mitochondrial membranes occurred very rapidly with complete loss at 5-10 µM. Sunitinib inhibited Complex I with an IC₅₀ value of 38 µM and caused ATP depletion, caspase 3/7 activation, an increase in reactive oxygen species (ROS), and decreased nucleoside and glucose uptake. In conclusion, imatinib, sunitinib and sorafenib caused changes in mitochondrial complex activities, glucose and nucleoside uptake leading to decreased energy production and mitochondrial function in a skeletal muscle cell model, suggesting that these changes may play a role in fatigue, one of the most common adverse effects of TKIs.

Interactions of lean soft-tissue and chemotherapy toxicities in patients receiving anti-cancer treatments

Use of cross-sectional imaging to identify whole-body lean soft-tissue mass has recently emerged as an attractive prognostic factor for chemotherapy toxicities. Beyond that, there is increasing interest in use of lean soft-tissue mass as a more accurate method for dosing chemotherapy, as compared to body surface area. In this review, we summarize the current evidence that supports interactions between skeletal muscle and chemotherapy, the role of lean soft tissue in predicting chemotherapy toxicities and potential use of an alternate method of chemotherapeutic dosing, all based on quantification of skeletal muscle mass by computed tomography.

Visceral adiposity increases risk for hepatocellular carcinoma in male patients with cirrhosis and recurrence after liver transplant

Visceral adipose tissue (VAT) is a metabolically active organ, associated with higher risk of malignancies. We evaluated whether VAT is associated with the risk of hepatocellular carcinoma (HCC) in patients presenting with cirrhosis as well as HCC recurrence after liver transplantation (LT). Patients with cirrhosis (n = 678; 457 male) who were assessed for LT (289 with HCC) were evaluated for body composition analysis. Patients who underwent LT (n = 247, 168 male) were subsequently evaluated for body composition, and 96 of these patients (78 male) had HCC. VAT, subcutaneous adipose tissues, and total adipose tissues were quantified by computed tomography at the level of the third lumbar vertebra and reported as indexes (cross-sectional area normalized for height [square centimeters per square meter]). At the time of LT assessment, the VAT index (VATI) was higher in male patients with HCC compared to non-HCC patients (75 ± 3 versus 60 ± 3 cm² /m² , P = 0.001). The VATI, subcutaneous adipose tissue index, and total adipose tissue index were higher in male patients with HCC compared to non-HCC patients. By multivariate analysis, male patients with VATI ≥65 cm² /m² had a higher risk of HCC (hazard ratio, 1.90; 95% confidence interval, 1.31-2.76; P = 0.001). In male patients with HCC who underwent LT, a VATI ≥65 cm² /m² adjusted for Milan criteria was independently associated with higher risk of HCC recurrence (hazard ratio, 5.34; 95% confidence interval, 1.19-23.97; P = 0.03).

CONCLUSION

High VATI is an independent risk factor for HCC in male patients with cirrhosis and for recurrence of HCC after LT. (Hepatology 2018;67:914-923).

Poor Physical Function as a Marker of Sarcopenia in Adults with Class II/III Obesity

BACKGROUND

Adults with class II/III obesity [body mass index (in kg/m2) ≥35] may present with a phenotype characterized by low lean mass and excess fat mass, a condition known as sarcopenic obesity (SO). Little is known about the prevalence and relevance of SO in these individuals, primarily due to a lack of relevant diagnostic criteria.

OBJECTIVE

Here, we explored the definition of SO based on physical function as an outcome of interest in adults with class II/III obesity and applied this definition to compare clinical characteristics between SO and non-SO patients.

METHODS

In this cross-sectional analysis, patients' demographic, anthropometric, and biochemical characteristics, as well as comorbidities and physical activity levels, were collected at an obesity specialty clinic prior to any treatment. Body composition was assessed by dual-energy X-ray absorptiometry. Physical function was assessed by self-reported difficulties with activities of daily living (ADLs) from an 11-item questionnaire. Five SO definitions were tested against reported difficulty with ADLs with the use of receiver operating characteristic (ROC) analysis.

RESULTS

A total of 120 subjects (86% women) aged 46 ± 11 y were included. Based on ROC analysis, SO was best defined by an appendicular skeletal mass (ASM)/weight x 100 (%) <19.35% for women and <24.33% for men, resulting in a prevalence of 25% (n = 30, women 22.3%, men 41.2%). SO was significantly associated with older age, higher waist circumference, higher triglycerides, greater use of antihypertensive medications, and lower physical activity.

CONCLUSIONS

In this sample of adults with class II/III obesity, difficulties with ADLs were best associated with measures of ASM in relation to total body weight. Patients identified with SO using this criterion presented with poorer clinical outcomes such as factors of elevated cardiometabolic risk.

Barriers to the Interpretation of Body Composition in Colorectal Cancer: A Review of the Methodological Inconsistency and Complexity of the CT-Defined Body Habitus

BACKGROUND

Measurement of body composition by computed tomography (CT) is an advancing field. Sarcopenia, myosteatosis, and visceral obesity (VO) have been identified as predictive of survival in colorectal cancer (CRC). We performed a systematic review of contemporary studies to characterize this association and highlight methodological inconsistencies.

METHODS

MEDLINE and PubMed were queried for articles published from January 2000 on, with populations of resectable CRC and with CT-measured body composition and survival data. The study quality was assessed by two independent reviewers using the Newcastle-Ottawa Scale.

RESULTS

Twenty studies met inclusion criteria, with a total of 8895 patients. Only two of the studies scored as high quality and nine as moderate quality. The remaining nine studies scored as low quality. Ten studies considered sarcopenia and 12 considered visceral obesity (VO). Cutoff points to define sarcopenia, myosteatosis, and VO were identified by optimal stratification, quartiles, or median values. The prevalence of sarcopenia varied from 15 to 60%, which based on study population and cutoff value used. Sarcopenia was associated with worse overall and disease-free survival in eight of the included studies. Myosteatosis was considered in three studies with a prevalence of 19-78%. It was significantly predictive of worse overall and disease-free survival in all three studies. VO had a prevalence of 14-70% and was inconsistently predictive of survival outcomes.

CONCLUSIONS

There is a lack of methodological consistency within the currently published literature. Despite this, sarcopenia and myosteatosis, but not VO, are consistently associated with worse survival outcomes, when population and cancer-specific cutoffs are utilized.

Nivolumab + ipilimumab combination in patients with DNA mismatch repair-deficient/microsatellite instability-high (dMMR/MSI-H) metastatic colorectal cancer (mCRC): First report of the full cohort from CheckMate-142

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Background: Nivolumab (NIVO) provided durable responses (investigator-assessed [INV] ORR, 31%) and disease control (DCR, 69%) in pretreated pts with dMMR/MSI-H mCRC in CheckMate-142 (NCT02060188; Overman et al Lancet Oncol 2017). An interim analysis of the NIVO + ipilimumab (IPI) combination cohort of CheckMate-142 reported a preliminary ORR of 55% and manageable safety profile in a subset of pts (n = 84) with dMMR/MSI-H mCRC and ≥ 6 mo of follow-up (André et al ASCO 2017). Here we report for the first time efficacy and safety from the complete population (N = 119) of the NIVO + IPI cohort of CheckMate-142, which is the largest single-study report of an immunotherapy regimen in pts with dMMR/MSI-H mCRC. Methods: Pts with dMMR/MSI-H mCRC received NIVO 3 mg/kg + IPI 1 mg/kg Q3W for 4 doses followed by NIVO 3 mg/kg Q2W. Primary endpoint was ORR (INV; RECIST 1.1). Other endpoints were DOR, PFS, OS, and safety/tolerability. Results: Of 119 treated pts, 76% had ≥ 2 prior lines of therapy. Median follow-up was 13.4 mo. The ORR was 55% and DCR was 80% (Table). Notably, ORR in pts with a BRAF mutation was 55%. Among all responders, median DOR was not reached (NR), with 94% of responses ongoing at data cutoff. Tumor burden was reduced from baseline in 77% of pts. The 9-mo PFS and OS rates were 76% and 87%, respectively. Gr 3–4 TRAEs occurred in 32% of pts; 13% (any gr) and 10% (gr 3–4) of pts had TRAEs that led to discontinuation. No treatment-related deaths were reported. Results including a similar follow-up of the NIVO arm will also be presented. Conclusions: In the largest cohort of dMMR/MSI-H pts treated with an immunotherapy regimen, NIVO + IPI built on the efficacy reported with NIVO monotherapy, demonstrating enhanced clinical benefit and manageable safety, and may represent a new standard of care in pts with dMMR/MSI-H mCRC. Clinical trial information: NCT02060188. [Table: see text]

Effects of proton pump inhibitors (PPIs) on FOLFOX and XELOX regimens in colorectal cancer (CRC)

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Title: Effects of Proton Pump Inhibitors (PPIs) on FOLFOX and XELOX Regimens in Colorectal Cancer (CRC) Background: First-line adjuvant chemotherapy options for stage II-III CRC include XELOX (capecitabine (cape), oxaliplatin) and FOLFOX (oxaliplatin, leucovorin, 5FU). Cape is an oral 5FU prodrug, and recent studies suggested that PPIs may detrimentally affect cape efficacy. Conversely, some literature posits that PPIs may negatively impact CRC itself. Our primary objective was to compare 3-year recurrence-free survival (RFS) rates between XELOX-treated PPI-users and non-PPI users, and FOLFOX-treated PPI users and non-PPI users. Our main secondary objective was to compare overall survival (OS). Methods: We conducted a retrospective chart review of 389 stage II-III CRC patients (pts) who received adjuvant XELOX or FOLFOX from a tertiary cancer center in Alberta, Canada between 2004-2013. Information regarding PPI use, cancer treatment, and pt outcomes were gathered and analyzed from pharmacy databases. Results: 23.4% of XELOX-treated pts and 28.0% of FOLFOX -treated pts used PPIs concurrently with treatment. 3-year RFS was significantly lower in XELOX-treated PPI pts than non-PPI pts (69.5 vs. 82.6%, P=0.029). Unadjusted analysis showed that XELOX-treated PPI pts were twice as likely to experience cancer recurrence or death as XELOX-treated non-PPI pts (HR 2.03, P=0.033). FOLFOX-treated PPI pts had a non-significant increase in three-year RFS versus non-PPI pts (82.9 vs. 61.7%, P=0.066), and no significant difference in recurrence or death (HR 0.51, P=0.071). No significant differences were seen in OS. Conclusions: Our results suggest that PPIs negatively impacted RFS in early-stage XELOX-treated CRC pts, and yielded no significant effect amongst FOLFOX-treated patients. Further studies are required to corroborate our findings. [Table: see text]

Clinical implications of muscle mass and quality in early-stage colorectal cancer (CRC)

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Background: Body composition has emerged as a potential prognostic factor for outcomes in early-stage CRC. Specifically, muscle mass and quality and visceral fat have been shown to be related to overall survival (OS) and disease-free survival (DFS). The objective of this study was to determine associations of sarcopenia, reduced skeletal muscle radiodensity (SMR) and visceral obesity (VO) with 5-year OS and DFS. Methods: Muscle and visceral fat at the time of diagnosis were quantified in a retrospective cohort of consecutive, early-stage CRC patients (pts), identified from a prospectively collected cancer database. Skeletal muscle area on computed tomography (CT) was measured and normalized by height (m2) in order to compare skeletal muscle index (SMI) between pts. Mean SMR and visceral fat area were measured. All parameters were analyzed using Kaplan-Meier curves and univariate Cox regression. Sarcopenia was defined as SMI < 41 cm2/m2 in females and < 43 cm2/m2 in males with BMI < 25 kg/m2 and < 53 cm2/m2 with BMI > 25 kg/m2. Reduced SMR was defined as < 41 HU if BMI < 25 kg/m2 and < 33 HU if BMI > 25 kg/m2. VO was defined as VAT > 160cm2 in males and > 80cm2 in females. Results: We identified 968 pts with available CTs and anthropometric data. Prevalence of sarcopenia was 44.5% in males and 59.6% in females. Myosteatosis was present in 60.9% of pts. The mean length of follow up was 5.0 years, with 254 patients developing recurrent disease and 351 deaths. Males with sarcopenia and myosteatosis had worse overall survival (HR, 0.69, p = 0.005; HR 0.49, p < 0.001) but no difference in DFS. Presence of VO was not associated with worse OS or DFS. There was no difference in OS for females with sarcopenia or VO, but myosteatosis predicted reduced OS (HR 0.53, p = 0.004). There was no difference in DFS for females by presence of sarcopenia, myosteatosis or VO. Conclusions: Body composition, specifically sarcopenia and myosteatosis, are highly prevalent in CRC pts treated with curative intent, and their presence is associated with reduced OS. Therefore, skeletal muscle mass and radiodensity are important prognostic factors in CRC outcomes, which are easily attained in a clinical setting.

Durable Clinical Benefit With Nivolumab Plus Ipilimumab in DNA Mismatch Repair-Deficient/Microsatellite Instability-High Metastatic Colorectal Cancer

Purpose Nivolumab provides clinical benefit (objective response rate [ORR], 31%; 95% CI, 20.8 to 42.9; disease control rate, 69%; 12-month overall survival [OS], 73%) in previously treated patients with DNA mismatch repair-deficient (dMMR)/microsatellite instability-high (MSI-H) metastatic colorectal cancer (mCRC); nivolumab plus ipilimumab may improve these outcomes. Efficacy and safety results for the nivolumab plus ipilimumab cohort of CheckMate-142, the largest single-study report of an immunotherapy combination in dMMR/MSI-H mCRC, are reported. Patients and Methods Patients received nivolumab 3 mg/kg plus ipilimumab 1 mg/kg once every 3 weeks (four doses) followed by nivolumab 3 mg/kg once every 2 weeks. Primary end point was investigator-assessed ORR. Results Of 119 patients, 76% had received ≥ two prior systemic therapies. At median follow-up of 13.4 months, investigator-assessed ORR was 55% (95% CI, 45.2 to 63.8), and disease control rate for ≥ 12 weeks was 80%. Median duration of response was not reached; most responses (94%) were ongoing at data cutoff. Progression-free survival rates were 76% (9 months) and 71% (12 months); respective OS rates were 87% and 85%. Statistically significant and clinically meaningful improvements were observed in patient-reported outcomes, including functioning, symptoms, and quality of life. Grade 3 to 4 treatment-related adverse events (AEs) occurred in 32% of patients and were manageable. Patients (13%) who discontinued treatment because of study drug-related AEs had an ORR (63%) consistent with that of the overall population. Conclusion Nivolumab plus ipilimumab demonstrated high response rates, encouraging progression-free survival and OS at 12 months, manageable safety, and meaningful improvements in key patient-reported outcomes. Indirect comparisons suggest combination therapy provides improved efficacy relative to anti-programmed death-1 monotherapy and has a favorable benefit-risk profile. Nivolumab plus ipilimumab provides a promising new treatment option for patients with dMMR/MSI-H mCRC.

Association of Proton Pump Inhibitors and Capecitabine Efficacy in Advanced Gastroesophageal Cancer: Secondary Analysis of the TRIO-013/LOGiC Randomized Clinical Trial

Importance

Capecitabine is an oral cytotoxic chemotherapeutic commonly used across cancer subtypes. As with other oral medications though, it may suffer from drug interactions that could impair its absorption.

Objective

To determine if gastric acid suppressants such as proton pump inhibitors (PPIs) may impair capecitabine efficacy.

Design, Setting, and Participants

This secondary analysis of TRIO-013, a phase III randomized trial, compares capecitabine and oxaliplatin (CapeOx) with or without lapatinib in 545 patients with ERBB2/HER2-positive metastatic gastroesophageal cancer (GEC); patients were randomized 1:1 between CapeOx with or without lapatinib. Proton pump inhibitor use was identified by medication records. Progression-free survival (PFS) and overall survival (OS) were compared between patients treated with PPIs vs patients who were not. Specific subgroups were accounted for, such as younger age (<60 years), Asian ethnicity, female sex, and disease stage (metastatic/advanced) in multivariate Cox proportional hazards modeling. The TRIO-013 trial accrued and randomized patients between June 2008 and January 2012; this analysis took place in January 2014.

Interventions

Patients were divided based on PPI exposure.

Main Outcomes and Measures

Primary study outcome was PFS and OS between patients treated with PPIs vs patients who were not. Secondary outcomes included disease response rates and toxicities.

Results

Of the 545 patients with GEC (median age, 60 years; 406 men [74%]) included in the study, 229 received PPIs (42.0%) and were evenly distributed between arms. In the placebo arm, PPI-treated patients had poorer median PFS, 4.2 vs 5.7 months (hazard ratio [HR], 1.55; 95% CI, 1.29-1.81, P < .001); OS, 9.2 vs 11.3 months (HR, 1.34; 95% CI, 1.06-1.62; P = .04); and disease control rate (83% vs 72%; P = .02) vs patients not treated with PPIs. In multivariate analysis considering age, race, disease stage, and sex, PPI-treated patients had poorer PFS (HR, 1.68; 95% CI, 1.42-1.94; P < .001) and OS (HR, 1.41; 95% CI, 1.11-1.71; P = .001). In patients treated with CapeOx and lapatinib, PPIs had less effect on PFS (HR, 1.08; P = .54) and OS (HR, 1.26; P = .10); however, multivariate analysis in this group demonstrated a significant difference in OS (HR, 1.38; 95% CI, 1.06-1.66; P = .03).

Conclusions and Relevance

Proton pump inhibitors negatively effected capecitabine efficacy by possibly raising gastric pH levels, leading to altered dissolution and absorption. These results are consistent with previous erlotinib and sunitinib studies. Whether PPIs affected lapatinib is unclear given concurrent capecitabine. Given capecitabine's prevalence in treatment breast cancer and colon cancer, further studies are under way.

Trial Registration

clinicaltrials.gov Identifier: NCT00680901.

A review of body composition and pharmacokinetics in oncology

INTRODUCTION

Body surface area dosing of chemotherapeutic agents is based on limited scientific data, and often results in unpredictable plasma drug levels. Cross-sectional computed tomography (CT) imaging provides an accurate measurement of lean mass. This review summarizes emerging roles of lean mass in predicting pharmacokinetics and drug toxicities in cancer patients. Areas covered: A concise review of body composition measurement with CT cross-sectional imaging and its relationship to drug pharmacokinetics and toxicities. A comprehensive review of the predictive value of low lean mass (sarcopenia) in dose-limiting toxicities is also included. Expert commentary: Drug dosing in medical oncology faces many challenges, including heterogeneous body composition profiles. The emerging role of sarcopenia in predicting lean mass may provide the tool needed to more accurately dose patients and prevent dose-limiting toxicities.

Utility of PET/CT in primary identification and management of cancers of unknown primary

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Background: The role of PET/CT in staging and management of cancers of unknown primary (CUP) is poorly defined. Our study sought to evaluate PET/CT versus standard CT in determining the primary site, lymph node status and solid organ metastases, and assess whether results of PET scans altered management of patients with CUP. Methods: We conducted a retrospective chart review of CUP patients to measure concordance of PET/CT and CT scans in patients diagnosed with CUP at two Western Canadian academic centres; the Cross Cancer Institute and BC Cancer Agencies from 2008 to 2015. Results: We identified 244 patients who had standard CT and PET/CT during their work-up. Of the 70 patients whose primary identification status was recorded, standard CT imaging detected 16.1% of primaries compared to 12.1% on PET/CT. 63.3% of primaries were concordantly identified on both modalities. PET/CT identified 2 primaries not seen on CT whereas standard CT identified 9 primaries not seen on PET/CT. Concordance rates between PET/CTs and standard CTs were 77.9% and 93.9% regarding lymph node status and extent of metastases, respectively. PET/CT identified a greater extent lymph node involvement in patients; 93.8% versus 79.0%. (CCOR = 2.92, 95% CI = 0.87-9.72) and identified a greater extent of solid organ involvement; 96.5% versus 92.4%. (CCOR = 45.25, 95% CI = 7.79-262.78). Data from the CCI of patients who had discordant imaging in either domain or identification of primary showed no cases in which PET/CT alone provided information that changed patient management. Conclusions: Our results suggest PET/CT scans do not provide additional diagnostic information with respect to identifying the primary site but may be superior in clarifying extent of metastases and nodal status though this did not alter therapy. Future studies investigating the impact of PET/CT scans on management and cost effectiveness in CUP are critical.

Skeletal muscle density is an independent predictor of diffuse large B-cell lymphoma outcomes treated with rituximab-based chemoimmunotherapy

BACKGROUND

While much cancer research focuses on tumours and their microenvironment, malignancies cause widespread physiologic changes. Cancer and treatment-related sarcopenia, measured with quantitative imaging or as a decrease in overall body mass, are indicative of poor prognosis in elderly diffuse large B-cell lymphoma (DLBCL) patients, skeletal muscle radiodensity (SMD) may be a better prognostic marker. SMD, a measure of muscle radiation attenuation on CT imaging, is more prognostic than sarcopenia or International Prognostic Index (IPI) scores in follicular lymphoma and multiple solid organ malignancies. Low SMD appears to correlate with fat accumulation in muscle and is associated with inflammation. This study set out to examine SMD's prognostic ability in DLBCL.

METHODS

All DLBCL patients treated with rituximab-containing therapy between 2004 and 2009 were compared to determine SMD's prognostic ability in this single centre, retrospective study. Pre-treatment CT scans were used to measure SMD and muscle cross-sectional area. Primary endpoints included progression free (PFS) and overall survival (OS) while objective response rates (ORR) were secondary.

RESULTS

Of 224 evaluable patients, 116 were identified as having low SMD. Low SMD predicted poorer 5 year PFS, 60 vs. 81% (p = 0.001) and OS, 58 vs. 86% (p < 0.0001). SMD's prognostic ability retained significance in multivariate analysis taking into consideration the Revised International Prognostic Index (R-IPI) and sex. Although high SMD was not predictive of ORR (95.4 vs. 91.4%, p = 0.17), it was strongly associated with radiographic complete response (85 vs. 66%, p = 0.0007). Contrary to previous findings, sarcopenia did not predict for poorer OS but suggested improved OS in elderly DLBCL patients (HR 0.38, p = 0.01).

CONCLUSIONS

SMD is a novel prognostic (and potentially treatment predictive) marker independent of R-IPI in DLBCL. It presents an inexpensive yet complementary assessment to R-IPI for prognosticating DLBCL outcomes.

A Nutritional Perspective of Ketogenic Diet in Cancer: A Narrative Review

The predominant use of glucose anaerobically by cancer cells (Warburg effect) may be the most important characteristic the majority of these cells have in common and, therefore, a potential metabolic pathway to be targeted during cancer treatment. Because this effect relates to fuel oxidation, dietary manipulation has been hypothesized as an important strategy during cancer treatment. As such, the concept of a ketogenic diet (KD) in cancer emerged as a metabolic therapy (ie, targeting cancer cell metabolism) rather than a dietary approach. The therapeutic mechanisms of action of this high-fat, moderate-to-low protein, and very-low-carbohydrate diet may potentially influence cancer treatment and prognosis. Considering the lack of a dietetics-focused narrative review on this topic, we compiled the evidence related to the use of this diet in humans with diverse cancer types and stages, also focusing on the nutrition and health perspective. The use of KD in cancer shows potentially promising, but inconsistent, results. The limited number of studies and differences in study design and characteristics contribute to overall poor quality evidence, limiting the ability to draw evidence-based conclusions. However, the potential positive influences a KD may have on cancer treatment justify the need for well-designed clinical trials to better elucidate the mechanisms by which this dietary approach affects nutritional status, cancer prognosis, and overall health. The role of registered dietitian nutritionists is demonstrated to be crucial in planning and implementing KD protocols in oncology research settings, while also ensuring patients' adherence and optimal nutritional status.