Use of patient-reported outcomes (PROs) to predict treatment outcomes in patients with advanced cancer

186

Background: PROs assessing quality of life (QOL) and physical symptoms often correlate with clinical outcomes in patients (pts) with cancer. Yet, data are lacking about the use of PROs to predict treatment response. We evaluated associations of baseline PROs with treatment response, healthcare use, and survival among pts with advanced gastrointestinal cancer. Methods: We prospectively enrolled pts with metastatic gastrointestinal cancer prior to initiating chemotherapy at Massachusetts General Hospital. At baseline (start of treatment), pts reported their QOL (Functional Assessment of Cancer Therapy General [FACT-G], subscales assess QOL across 4 domains: functional, physical, emotional, social well-being) and symptom burden (Edmonton Symptom Assessment System [ESAS]). Higher scores on FACT-G indicate better QOL, while higher scores on ESAS represent a greater symptom burden. We used regression models to examine associations of baseline PRO scores with treatment response (clinical benefit [CB] or progressive disease [PD] at the time of first scan based on clinical documentation), healthcare use (unplanned hospital admissions), and survival. Results: From 5/2019-3/2020, we enrolled 112 of 131 (85.5% enrollment) consecutive pts (median age = 62.8, 61.6% male, 45.5% pancreatobiliary cancer). For treatment response, 64.3% had CB and 35.7% had PD. Higher ESAS-physical (B = 1.04, p = .027) and lower FACT-G functional (B = 0.92, p = .038) scores at baseline were significant predictors of PD. On the specific ESAS items, pts who experienced PD were more likely to report moderate/severe poor well-being (57.9% vs 29.7%; p = .001), pain (44.7% vs 25.0%; p < .050), drowsiness (42.1% vs 20.3%; p = .024), and diarrhea (23.7% vs 4.7%; p = .008) at baseline. Lower FACT-G total (HR = 0.96, p = .003), FACT-G physical (HR = 0.89, p < .001), FACT-G functional (HR = 0.87, p < .001), and higher ESAS-physical (HR = 1.03, p = .028) scores at baseline were significantly associated with greater risk of hospital admission. Lower FACT-G total (HR = 0.96, p = .009), FACT-G emotional (HR = 0.87, p = .014), as well as higher ESAS-total (HR = 1.03, p = .018) and ESAS-physical (HR = 1.03, p = .040) scores at baseline were significantly associated with greater risk of death. Conclusions: We found that baseline PROs predict treatment response in pts with advanced cancer, namely physical symptoms and functional QOL, in addition to healthcare use and survival outcomes. These findings further support the use of PROs to predict important clinical outcomes, including the novel finding of treatment response.

Leveraging patient-reported outcomes (PROs) in patients with pancreatic cancer: The Pancreatic Cancer Action Network (PanCAN) online patient registry experience

154

Background: By allowing patients (pts) to self-report key issues related to their quality of life and symptoms, PROs have important clinical and research implications. The PanCAN Registry, which began collecting data in July 2015, is a pancreatic cancer-specific global online registry enabling pts to report sociodemographics, disease/management characteristics, and PROs via online surveys. We sought to describe pt experiences with the PanCAN Registry. Methods: We assessed individual characteristics and interactions with the registry (visits, survey completions, and longitudinal use) from 7/2015-10/2019 for pts who provided permission to use their data. The registry allows pts to complete surveys about their experience (e.g. basics of pancreatic cancer, general information), symptoms (e.g. fatigue, pain), diagnostics (e.g. labs, scans), and drug therapy (e.g. type, frequency). We validated PROs using the PanCAN Know Your Tumor database. For a subset of pts (those with de novo metastatic disease), we compared PROs, treatment patterns, and side effects by age (+/- 65 years) and treatment site (community or academic). Results: Of 2,836 pts who visited the registry, 2,076 (73%) completed at least one survey (median age = 64 [range: 18-97], 48% women, 92% white, 32% metastatic disease). Pts most commonly completed the basics (73%), general information (39%), and drug therapy (37%) surveys. Overall, 10% answered surveys longitudinally. We observed 95% concordance between PROs and the PanCAN Know Your Tumor database. Among the 667 pts with de novo metastatic disease, 34% were older (age 65+) and 50% were treated at academic sites. Younger pts were more hopeful about the treatment plan (strongly agree: 24% v 12%, p < .01) and reported less constipation (moderate/severe: 33% v 48%, p < .01) compared with older pts. Pts treated at academic sites reported less frequent treatment breaks of > 2 weeks (28% v 58%, p = 0.01) and more frequent severe cytopenias (27% v 12%, p = 0.01) compared with those treated at community sites. Conclusions: With > 2,800 pts visiting the PanCAN registry and > 70% completing a survey, these findings demonstrate the feasibility, robustness, and research potential of an online PRO registry. We observed important differences by age and treatment site regarding pts’ outlook, symptoms, treatment patterns, and side effects. With increasing focus on PROs, registries like this can facilitate standardized PRO reporting and monitoring, while also providing a valuable research database.

Relationships among skeletal muscle, symptom burden, health care use, and survival in hospitalized patients with advanced cancer

7006

Background: Loss of skeletal muscle mass (quantity) is common in patients with advanced cancer, but little is known about muscle density (quality). Hospitalized patients with advanced cancer are a highly symptomatic population at risk for the adverse effects of muscle loss. Thus, we sought to describe associations between muscle mass and density, symptom burden, health care use, and survival in these patients. Methods: We prospectively enrolled hospitalized patients with advanced cancer from 9/2014-4/2017. Upon admission, patients reported their physical (Edmonton Symptom Assessment System [ESAS]) and psychological (Patient Health Questionnaire 4 [PHQ4]) symptoms. We used computed tomography (CT) scans performed per routine care ≤45 days prior to enrollment to evaluate muscle mass and density at the level of the third lumbar vertebral body. We categorized patients as sarcopenic using validated sex specific cutoffs. We used regression models to examine associations between muscle mass and density and patients’ symptom burden, health care use, and survival. Results: Of 1,121 patients enrolled, 677 had evaluable CT scan data (mean age = 62.86±12.95 years; 51.1% female). The most common cancer types were gastrointestinal (36.8%) and lung (16.7%) cancer. Most met criteria for sarcopenia (64.0%). Older age and female sex were associated with lower muscle mass (age: B = -0.16, p < .01; female: B = -6.89, p < .01) and density (age: B = -0.33, p < 0.01; female: B = -1.66, p = .01), while higher BMI was associated with higher muscle mass (B = 0.58, p < .01) and lower muscle density (B = -0.61, p < .01). Higher muscle mass was significantly associated with improved survival (HR = 0.97, p < .01), but not with symptom burden or health care use. Higher muscle density was significantly associated with lower ESAS physical (B = -0.17, p = .02), ESAS total (B = -0.29, p < .01), PHQ4 depression (B = -0.03, p < .01) and PHQ4 anxiety (B = -0.03, p < .01) symptoms. Higher muscle density was also associated with decreased hospital length of stay (B = -0.07, p < .01), risk of readmission or death in 90 days (OR = 0.97, p < .01), and improved survival (HR = 0.97, p < .01). Conclusions: Most hospitalized patients with advanced cancer have muscle loss consistent with sarcopenia. We found that muscle mass (quantity) correlated with survival, whereas muscle density (quality) was associated with patients’ symptoms, health care use, and survival. These findings underscore the added importance of assessing muscle quality when seeking to address the adverse effects of muscle loss in oncology.

Work loss and activity impairment due to duration of nausea and vomiting in patients with breast cancer receiving CINV prophylaxis

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Background: The impact of chemotherapy-induced nausea and vomiting (CINV) on work loss and activity impairment is important to patients yet not well described in literature. We sought to evaluate CINV-related work loss and activity impairment and their associations with CINV duration. Methods: In a prospective CINV prophylaxis trial of oral or intravenous netupitant/palonestron (NEPA) + dexamethasone (DEX) (12mg day 1 only) for patients with breast cancer receiving anthracycline + cyclophosphamide (AC), we defined CINV as vomiting or use of rescue medication during days 1-5 after AC. Pre-specified endpoints included CINV duration (0-5 days), patient reported CINV-associated work loss (Work Productivity and Activity Impairment survey), and CINV-related impaired activity [0 (none) - (worst) Likert scale] for chemotherapy cycles 1 and 2. CINV-related work loss and activity impairment could involve nausea with or without vomiting or rescue medication use. We categorized CINV duration as 1-2 days (d) or ≥3 d, and compared results using the chi-squared test. We report here on the first 2 cycles. Results: Survey data was captured for 792 cycles in 402 female patients including 132 (32.8%) employed patients. Mean age was 55.4. CINV was observed in 173 (21.8%) of total cycles. CINV-related work loss was reported in 26 (3.3% of all cycles, 15.0% of cycles with CINV, 38.2% of employed patient cycles with CINV) while 142 had related activity impairment. When we categorized cycles by CINV duration, CINV-related work loss was seen in 25.9% of 81 cycles with ≥3 d CINV duration vs. 5.4% for 92 cycles of 1-2 d of CINV (p < 0.001); mean scores of CINV-related impaired activity were 5.0 for ≥3 d CINV vs 3.0 for 1-2 d CINV (p < 0.001). Conclusions: Despite guideline recommended prophylaxis, CINV occurred in > 20% of AC cycles. In cycles with CINV, CINV-related work loss occurred in 38.2% for employed patients while activity impairment occurred in 82.1% for all patient cycles. The majority of CINV lasted 1-2 d. Notably, ≥3 d of CINV was associated with considerably higher levels of work loss and activity impairment suggesting that duration may be a meaningful measure of CINV impact. Clinical trial information: NCT03403712 . [Table: see text]

Serial ctDNA Monitoring to Predict Response to Systemic Therapy in Metastatic Gastrointestinal Cancers

PURPOSE

ctDNA offers a promising, noninvasive approach to monitor therapeutic efficacy in real-time. We explored whether the quantitative percent change in ctDNA early after therapy initiation can predict treatment response and progression-free survival (PFS) in patients with metastatic gastrointestinal cancer.

EXPERIMENTAL DESIGN

A total of 138 patients with metastatic gastrointestinal cancers and tumor profiling by next-generation sequencing had serial blood draws pretreatment and at scheduled intervals during therapy. ctDNA was assessed using individualized droplet digital PCR measuring the mutant allele fraction in plasma of mutations identified in tumor biopsies. ctDNA changes were correlated with tumor markers and radiographic response.

RESULTS

A total of 138 patients enrolled. A total of 101 patients were evaluable for ctDNA and 68 for tumor markers at 4 weeks. Percent change of ctDNA by 4 weeks predicted partial response (PR, P < 0.0001) and clinical benefit [CB: PR and stable disease (SD), P < 0.0001]. ctDNA decreased by 98% (median) and >30% for all PR patients. ctDNA change at 8 weeks, but not 2 weeks, also predicted CB (P < 0.0001). Four-week change in tumor markers also predicted response (P = 0.0026) and CB (P = 0.022). However, at a clinically relevant specificity threshold of 90%, 4-week ctDNA change more effectively predicted CB versus tumor markers, with a sensitivity of 60% versus 24%, respectively (P = 0.0109). Patients whose 4-week ctDNA decreased beyond this threshold (≥30% decrease) had a median PFS of 175 days versus 59.5 days (HR, 3.29; 95% CI, 1.55-7.00; P < 0.0001).

CONCLUSIONS

Serial ctDNA monitoring may provide early indication of response to systemic therapy in patients with metastatic gastrointestinal cancer prior to radiographic assessments and may outperform standard tumor markers, warranting further evaluation.

Phase IIIb Safety and Efficacy of Intravenous NEPA for Prevention of Chemotherapy-Induced Nausea and Vomiting (CINV) in Patients with Breast Cancer Receiving Initial and Repeat Cycles of Anthracycline and Cyclophosphamide (AC) Chemotherapy

BACKGROUND

NEPA, a combination antiemetic of a neurokinin-1 (NK1 ) receptor antagonist (RA) (netupitant [oral]/fosnetupitant [intravenous; IV]) and 5-HT3 RA, palonosetron] offers 5-day CINV prevention with a single dose. Fosnetupitant solution contains no allergenic excipients, surfactant, emulsifier, or solubility enhancer. A phase III study of patients receiving cisplatin found no infusion-site or anaphylactic reactions related to IV NEPA. However, hypersensitivity reactions and anaphylaxis have been reported with other IV NK1 RAs, particularly fosaprepitant in patients receiving anthracycline-cyclophosphamide (AC)-based chemotherapy. This study evaluated the safety and efficacy of IV NEPA in the AC setting.

MATERIALS AND METHODS

This phase IIIb, multinational, randomized, double-blind study enrolled females with breast cancer naive to highly or moderately emetogenic chemotherapy. Patients were randomized to receive a single 30-minute infusion of IV NEPA or single oral NEPA capsule on day 1 prior to AC, in repeated (up to 4) cycles. Oral dexamethasone was given to all patients on day 1 only.

RESULTS

A total of 402 patients were included. The adverse event (AE) profiles were similar for IV and oral NEPA and consistent with those expected. Most AEs were mild or moderate with a similarly low incidence of treatment-related AEs in both groups. There were no treatment-related injection-site AEs and no reports of hypersensitivity or anaphylaxis. The efficacy of IV and oral NEPA were similar, with high complete response (no emesis/no rescue) rates observed in cycle 1 (overall [0-120 hours] 73.0% IV NEPA, 77.3% oral NEPA) and maintained over subsequent cycles.

CONCLUSION

IV NEPA was highly effective and safe with no associated hypersensitivity and injection-site reactions in patients receiving AC.

IMPLICATIONS FOR PRACTICE

As a combination of a neurokinin-1 (NK1 ) receptor antagonist (RA) and 5-HT3 RA, NEPA offers 5-day chemotherapy-induced nausea and vomiting prevention with a single dose and an opportunity to improve adherence to antiemetic guidelines. In this randomized multinational phase IIIb study, intravenous (IV) NEPA (fosnetupitant/palonosetron) was safe and highly effective in patients receiving multiple cycles of anthracycline-cyclophosphamide (AC)-based chemotherapy. Unlike other IV NK1 RAs, the IV NEPA combination solution does not require any surfactant, emulsifier, or solubility enhancer and contains no allergenic excipients. Hypersensitivity reactions and anaphylaxis have been reported with other IV NK1 RAs, most commonly with fosaprepitant in the AC setting. Importantly, there were no injection-site or hypersensitivity reactions associated with IV NEPA.

Preliminary analysis of total neoadjuvant therapy for patients with locally advanced gastric (G) and gastroesophageal (GE) adenocarcinoma

393

Background: Nearly half of patients with G/GE cancer do not receive or complete post-operative chemotherapy and/or chemoradiation (CRT). Total neoadjuvant therapy (TNT) is as an emerging alternate treatment strategy. We have previously reported a 28% pCR with FOLFIRINOX followed by CRT. However, TNT outcomes with FLOT or FOLFOX followed by CRT are lacking. Methods: We retrospectively analyzed patients after resection of locally advanced G/GE after receiving TNT. Patient received neoadjuvant FOLFOX or FLOT x 8 cycles, CRT (G 45 Gy, GE 50.4 Gy) with concurrent chemotherapy (5FU, carboplatin/paclitaxel). The primary aim was to explore TNT completion rates. Secondary aims included pCR and toxicity. We performed descriptive statistics, t-test, chi-squared, and Fisher’s exact tests as appropriate. Results: From 12/2015 to 8/2019, 57.1% (40/70) completed TNT and resection (15.7% active treatment, 15.7% progressive disease, 11% treated elsewhere). Median age was 66.0 (range:27-79) and 73% male. Tumor locations included 57.5% G, 30.0% GE, and 12.5% overlapping. Neoadjuvant chemotherapy included FLOT 22.5% (n = 9) or FOLFOX 77.5% (n = 31). Overall we found a 25% pCR without significant differences between type of neoadjuvant chemotherapy. Conclusions: TNT followed by resection is feasible with acceptable rates of treatment completion and toxicity. Notable limitations include the retrospective analysis, small sample size, and heterogenous treatment. The pCR rate is promising and warrants further prospective study to optimize TNT approaches. [Table: see text]

Noninvasive comprehensive genomic profiling from plasma ctDNA in pancreatic cancer patients

753

Background: The use of comprehensive genomic profiling (CGP) is increasing in pancreatic ductal adenocarcinoma (PDAC) as knowledge improves regarding molecular drivers of tumorigenesis and effective targeted therapies emerge. However, adequate tissue sampling is often limited. Plasma-based CGP offers a non-invasive approach to assess biomarkers that may impact treatment decisions. Methods: We retrospectively evaluated genomic and clinical data from 97 PDAC patients with circulating tumor DNA (ctDNA) testing from 9/2016-8/2019 (Guardant Health, Inc.). ctDNA analysis included single nucleotide variants (SNV), fusions, indels and copy number variations (CNV) of up to 74 genes. ctDNA results were assessed across clinical variables. We evaluated for actionable alterations. Results: A total of 114 samples were obtained from 97 patients for ctDNA testing. ctDNA alterations were detected in 82% (93/114) of all samples, including 90% (18/20) at diagnosis, 88% (59/67) at progression, and 56% (10/18) while on stable therapy. ctDNA alterations were found at each stage of PDAC: in 25% (1/4) of samples with resectable disease, 75% (3/4) with borderline resectable disease, 82% (9/11) with locally advanced disease, and 85% (81/95) with metastatic disease. One or more KRAS alterations were detected in 55% (51/93) of patients with alterations present. The median maximum mutant allele frequency was similar between the cohort of patients with KRAS detected (0.55%) versus not detected (0.70%). 8% (8/97) of patients had potentially actionable alterations (2 activating BRAF SNVs, 1 ERBB2 CNV, 1 ERBB2 activating SNV, 1 KRAS G12C, and 3 indels in Homologous Recombination Deficiency genes). Median turnaround time was 8 days. 51% (49/97) of patients had both plasma-based CGP and tissue-based CGP. Of these patients, tissue-based CGP showed ≥ 1 alterations detected in 82% (40/49), test failure in 14% (7/49), and no alterations detected in 4% (2/49). Conclusions: Plasma-based CGP detected ctDNA alterations in 90% of samples tested at diagnosis and 82% of all samples. Potentially actionable mutations were found in 8% of patients, with prompt processing time allowing for rapid decision making.

The role of circulating tumor DNA (ctDNA), tumor markers (TMs), and patient-reported outcomes (PROs) in predicting treatment response in patients with metastatic gastrointestinal (GI) cancer

833

Background: Changes in ctDNA and serum TMs (CEA and CA19-9) can serve as predictors of response to systemic therapy in GI cancer patients (pts). Similarly, PROs correlate with survival and treatment response. We present a preliminary analysis of ctDNA, TMs, and PROs in predicting treatment response. Methods: We are enrolling 200 pts in a prospective study with metastatic pancreatic (PDAC), colorectal (CRC), gastroesophageal (GE), and biliary cancers. We are collecting ctDNA, TMs (CEA for all tumor types; CA19-9 for PDAC, GE, biliary), and PROs (FACT-G for QOL [higher scores indicate better QOL]; ESAS-r and PRO-CTCAE for symptoms; and PHQ-4 [consists of GAD-2 and PHQ-2 for anxiety and depression]; higher ESAS-r, PRO-CTCAE, and PHQ-4 scores reflect greater symptom burden) at baseline and 4 weeks. ctDNA is benchmarked against somatic tissue alterations, and serially assessed by digital droplet PCR. We correlated median percent change from baseline to 4 weeks for ctDNA, TMs, and PROs with treatment response (clinical benefit [CB], progressive disease [PD]). Results: From April to August 2019, we have enrolled 38/45 (84.4%) eligible pts (median age = 64 years; 36.8% female). Among these 38 pts, tumor types are PDAC (36.8%), CRC (31.6%), GE (28.9%), and biliary (2.6%). 18/38 pts were evaluable for ctDNA. Change in ctDNA was -94.5% in pts with CB (n = 10) and -19.5% in pts with PD (n = 8; p = 0.025). No correlation was observed between CEA and treatment response (p = 0.367). Change in CA19-9 was -1.5% for pts with CB and +47% for pts with PD (p = 0.019). Changes in PRO-CTCAE (p = 0.345), GAD-2 (p = 0.697), and ESAS scores (p = 0.743) did not differ between pts with CB and PD. However, changes in PHQ-2 (CB 0% v. PD +22.5%; p < 0.001), PHQ-4 (CB -8.5% v. PD +5%; p = 0.015), and FACT-G (CB +30% v. PD +5%; p = 0.049) were significant. Conclusions: Preliminary analysis suggests that ctDNA and PROs demonstrate promising utility for early prediction of treatment response, with favorable performance relative to standard TMs. Further analyses of larger pt numbers in this ongoing study may clarify the use and integration of these measures to better predict pt outcomes.

Analysis of weight loss as a prognostic factor in patients (pts) with advanced gastric cancer from REGARD, RAINBOW and RAINFALL phase III studies

348

Background: Maintaining weight (wt) and adequate nutrition during systemic treatment in advanced gastric cancer (G/GEJ) therapy remains a challenge. We investigated the impact of early wt-loss on survival in three phase 3 studies of ramucirumab (R); REGARD (RG), RAINBOW (RB), and RAINFALL (RF) in G/GEJ. Methods: ITT pts were categorized into 2 groups based on their body wt change from start to end of cycle 1 (C1; C = 28 days in RG, RB; C = 21 days in RF): wt-loss < 3% vs ≥3%. Univariate Cox PH models were performed in each individual study to evaluate the effects of body wt change from the start to end of C1 on OS. A pooled meta-analysis stratified by study and a sensitivity analysis of the subgroup of responders was also performed. Results: A total of 311 (RG: 212 in R+BSC; 99 in Placebo (PB)+BSC), 591 (RB: 306 in the R+Paclitaxel (P); 285 PB+P), and 562 (RF: 279 in R+Cape/Cis (CC); 283 in PB+CC) pts with body wt data during C1 were evaluated. The number of pts with wt-loss of ≥3% and < 3% are shown in Table. Pts with wt-loss < 3% during C1 experienced longer OS compared to those with wt-loss ≥3%, irrespective of treatment arms across studies (Table). In pooled treatment arms within each study, the HR for wt-loss group ( < 3% vs ≥3%) was 0.359 (95% CI = 0.254, 0.507), 0.632 (0.497, 0.804), 0.752 (0.608, 0.930) in RG, RB, RF, respectively. In the meta-analysis that combined the 3-studies, univariate Cox PH model stratified by study showed consistent effect of early wt-loss on OS regardless of treatment arm, HR ( < 3% vs ≥3%) = 0.632 (0.546, 0.732). Conclusions: Analysis from three phase 3 studies demonstrates early wt-loss ≥3% during C1 is an important negative prognostic factor for survival in gastric/GEJ cancer. Prospective studies of the relationship of weight preserving nutritional interventions on OS are warranted. Clinical trial information: NCT00917384, NCT01170663, NCT02314117.

[Table: see text]

Author Correction: Liquid versus tissue biopsy for detecting acquired resistance and tumor heterogeneity in gastrointestinal cancers

An amendment to this paper has been published and can be accessed via a link at the top of the paper.

Acute care and hydration due to chemotherapy-induced nausea and vomiting (CINV) among patients receiving NEPA prophylaxis for anthracycline + cyclophosphamide (AC)

112

Background: In the US, the CMS OP-35 oncology outcome measure deems 30-day post-chemotherapy acute care involving nausea and emesis (NV) or 8 other toxicities as avoidable, with studies showing 15% of > 2500 patients receiving anthracycline + cyclophosphamide (AC)-based chemotherapy had avoidable acute care, of which 32% involved NV. Our aim was to evaluate resource use (emergency department [ED] visits, inpatient admissions [IP], or hydration) in a prospective trial of women with breast cancer who received combination netupitant/palonosetron (NEPA) + dexamethasone (DEX) for CINV prophylaxis for AC-based chemotherapy. Methods: Women initiating AC received oral or IV NEPA + DEX. Pre-specified endpoints included safety, complete response, acute care (ED/IP), unplanned IV hydrations (as determined by investigator), days of CINV, and ≥3 days of CINV. We defined CINV as emesis or rescue drug use up to 5 days after AC, and defined concomitant ED/IP or hydrations in the same period as CINV-related. We limited our analysis to the first 2 cycles, the median duration in the NEPA study. Results: 402 patients received ≥1 cycle of AC and 391 completed 2 cycles. Nine patients had IP (none CINV-related), and 5 patients had a total of 6 ED visits (1 CINV-related). Three patients had a CINV-related unplanned hydration. Patients had ≥1 day of CINV in 172 of 793 cycles (21.7%); of these, the majority had symptom duration for 1-2 days, while 78 (9.8%) had ≥3 days of CINV in a cycle. Conclusions: In this prospective CINV prophylaxis study in women receiving AC chemotherapy, < 1% of women receiving NEPA + DEX required acute care for CINV and < 1% required unplanned hydrations for CINV. These rates are below previously reported CINV-related acute care rates for AC suggesting NEPA may help avoid CINV-related acute care. Clinical trial information: NCT03403712.

Abstract LB-257: Liquid biopsy versus tissue biopsy to assess acquired resistance and tumor heterogeneity in gastrointestinal cancers

The inevitable emergence of acquired resistance is a major limitation to the clinical benefit of precision medicine strategies. Single-lesion tumor biopsies have long been the mainstay of understanding acquired resistance, but recent data suggest tumor biopsies may under-represent the molecular heterogeneity of acquired resistance. Alternatively, studies have suggested that liquid biopsy approaches analyzing cell-free DNA (cfDNA) may offer significant advantages, but extensive prospective comparisons of matched liquid vs. tumor biopsies obtained at the time of acquired resistance are lacking. Here, we assess systematic liquid biopsy upon acquired resistance to targeted therapy in 44 patients across seven molecularly defined subtypes of gastrointestinal cancers. Liquid biopsy at disease progression identified at least one functionally validated molecular mechanism of resistance in 75% of patients, wherein 52% exhibited &gt;1 resistance alteration (range 2-9, median 3 per patient). In 23 patients in whom a matched post-progression tumor biopsy could be obtained, tumor biopsy was less effective than liquid biopsy in identifying resistance mechanisms, with resistance alterations detected in only 48% of patients, and multiple resistance mechanisms detected in only 9% of cases. In matched cases, liquid biopsy detected at least one resistance alteration not detected in tumor biopsy in 78% of cases. Targeted analysis and whole-exome sequencing of serial cfDNA, multiple post-progression biopsies, and rapid autopsy specimens from select cases revealed key insights into the geographic and complex characteristics of heterogeneity captured by liquid biopsy in the setting of acquired resistance. These data illustrate that acquired resistance is characterized by frequent and profound tumor heterogeneity, and suggests that liquid biopsy may more effectively identify heterogeneous clinically relevant resistance alterations compared to standard tumor biopsy.

Citation Format: Aparna R. Parikh, Ignaty Leshchiner, Liudmila Elagina, Lipika Goyal, Chaya Levovitz, Giulia Siravegna, Dimitri Livitz, Kahn Rhrissorrakrai, Liz Martin, Emily E. Van Seventer, Megan Hanna, Kara Slowik, Filippo Utro, Christopher J. Pinto, Alicia Wong, Brian P. Danysh, Ferran Fece de la Cruz, Isobel J. Fetter, Brandon Nadres, Heather A. Shahzade, Jill N. Allen, Lawrence S. Blaszkowsky, Jeffrey W. Clark, Bruce Giantonio, Janet E. Murphy, Ryan D. Nipp, Eric Roeland, David P. Ryan, Colin D. Weekes, Eunice L. Kwak, Jason E. Faris, Francois Aguet, Ipsita Guha, Mehlika Hazar-Rethinam, Dora Dias-Santagata, David T. Ting, Andrew X. Zhu, Theodore S. Hong, Todd R. Golub, A J. Iafrate, Viktor Adalsteinsson, Alberto Bardelli, Laxmi Parida, Dejan Juric, Gad Getz, Ryan B. Corcoran. Liquid biopsy versus tissue biopsy to assess acquired resistance and tumor heterogeneity in gastrointestinal cancers [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr LB-257.

Physician concordance with update to ASCO guidelines for antiemetic use with carboplatin AUC ≥ 4

11595

Background: In 2017, NCCN (2/2017) and ASCO (8/2017) each amended antiemetic guidelines to classify carboplatin AUC ≥4 as highly emetogenic chemotherapy (HEC), recommending upfront triple prophylaxis with an NK1 receptor antagonist (RA) + 5HT3 RA + dexamethasone. Physician concordance with the new recommendations, and the consequences for avoidable post-chemotherapy acute care, merit study. Methods: In a large electronic health record database (IBM Explorys), we identified carboplatin courses of therapy (≥14-day cycles as a proxy for AUC ≥4) and courses with ≥7-day cycles of other HEC and non-HEC therapy from 4Q 2012 through August 2018. Guideline concordance, defined as triple prophylaxis at HEC initiation, was evaluated. We also assessed 30-day post-chemotherapy acute care (inpatient or emergency department) associated with nausea or vomiting (NV) or eight other toxicities deemed avoidable in the US Centers for Medicare & Medicaid’s new oncology outcome measure OP-35. Results: 11,554 carboplatin courses were identified. Before the guideline change, rates of upfront triple prophylaxis grew from 14% in 2013 to 16% in mid-2017. Rates then rose to 26% by 1Q 2018 before dropping to 21% by 3Q 2018; quarterly rates averaged 20% (range 15%-26%) following the guideline change. In 31% of carboplatin courses we noted 30-day acute care use, of which 75% involved ≥1 of the ten OP-35 toxicities. NV (with or without acute care use) was reported in 24% of courses, and 27% of total OP-35 acute care events involved NV. Rates for NV, and for OP-35-related and NV-related acute care after carboplatin, were similar to rates after other HEC chemotherapy, and higher than rates after other non-HEC IV chemotherapy or oral HEC/MEC agents. Conclusions: Use of upfront triple antiemetic prophylaxis has increased only marginally for carboplatin AUC ≥ 4 since its 2017 re-classification as HEC in national guidelines, perhaps due to low awareness of the change. Patients receiving carboplatin had similar rates of NV and related 30-day acute care events as seen for other HEC, confirming that the new HEC definition fits clinical experience. More triple prophylaxis use is needed to reduce NV and NV-related avoidable acute care seen with carboplatin AUC ≥ 4.

A pilot study of neoadjuvant FOLFIRINOX followed by chemoradiation for gastric and gastroesophageal cancer: Preliminary results

4057

Background: We performed a single-arm pilot study of total neoadjuvant approach including FOLFIRINOX and chemoradiation (CRT) with concurrent carboplatin/taxol (C/T) followed by surgery in patients with locally advanced gastric or gastroesophageal junction (GEJ) cancer. Methods: Patients were enrolled on a NCI sponsored, prospective, single arm study (NCT03279237). Key eligibility criteria included: histologically confirmed T3/4 or lymph node (LN) positive gastric or GEJ cancer, ECOG PS ≤1, age 18+, life expectancy > 3 months. Exclusion criteria included: visceral metastases, prior chemotherapy or RT, or prior targeted therapy. Extensive LN disease beyond the surgical field (supraclavicular or para-aortic) was permitted if deemed feasible to be encompassed within a RT field. Laparoscopy was not required. Pts were treated with neoadjuvant FOLFIRINOX x 8, restaging, CRT (45 Gy for gastric, 50.4 Gy for GEJ) with concurrent C/T, restaging, followed by surgical resection. Dose reductions were at discretion of the treating physician. The primary objective was to determine the rate of completion of FOLFIRINOX x 8 followed by CRT delivered in the preoperative setting. Secondary endpoints included: 1) acute toxicity and 2) pathologic complete response (pCR). Results: From Oct 2017 to June 2018, 25 pts were enrolled. Median age was 60 (range:30-76), 17 pts were male (68%). All pts started FOLFIRINOX; 23 (92%) pts completed all 8 planned cycles. Two pts did not complete the planned 8 cycles due to metastatic progression. Rates of grade 3+ overall, gastrointestinal, and hematologic toxicities were 28%, 12%, and 28% respectively. Of the entire cohort, 23 (92%) pts started chemoRT and 22 (88%) pts completed chemoRT (1 pt died during CRT due to pulseless electrical activity arrest). All 22 pts (88%) who completed CRT went for surgical exploration, of whom 2 pts were found with intraoperative metastases. Therefore, 20 (80%) pts underwent surgical resection. At time of abstract, 1 pt’s pathology is in process; 7 pts had a pCR (37% in resected cohort, 28% in ITT cohort), all with R0 resection. Conclusions: Total neoadjuvant FOLFIRINOX followed by CRT is feasible with acceptable rates of treatment completion and grade 3+ toxicity. In our small series, the rate of pCR is promising and a follow-up study is currently planned. Clinical trial information: NCT03279237.

Ondansetron versus palonosetron as a marker of non-adherence to antiemetic prophylaxis guidelines in highly emetogenic chemotherapy

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Background: ASCO antiemetic guidelines recommend upfront triple prophylaxis (NK1 receptor antagonist (RA) + 5HT3 RA + dexamethasone) for patients receiving highly emetogenic chemotherapy (HEC). Physicians exhibit high variation in HEC guideline adherence, principally involving inclusion of NK1 RA. Whether adherence is associated with selection of the specific 5HT3 RA agent remains inadequately studied. Methods: In the IBM Explorys electronic health record database, we used procedure and diagnosis codes to identify HEC courses and related nausea/vomiting (NV) from 2012 to 2018. We defined HEC guideline adherence as triple prophylaxis at chemotherapy initiation. We assigned HEC courses for ≥ 7 day cycles of cisplatin or anthracycline + cyclophosphamide (AC), or carboplatin (≥ 14 day cycles as a proxy for AUC ≥ 4) to prescribing oncologists based on encounter frequency. We categorized 5HT3 RA use of each physician treating ≥ 5 HEC courses based on their most commonly used 5HT3 and performed descriptive statistics. Results: Of 12,262 HEC courses, 57% involved physicians having greater use of ondansetron (OND) (mean OND to palonosetron (PALO) ratio of 3.9:1). These courses had lower guideline adherence (due to NK1 RA omission) and higher rates of NV for combined HEC, AC, and carboplatin. NV rates for cisplatin did not vary by 5HT3 agent used. Courses involving physicians with greater PALO use (mean OND:PALO ratio of 0.2:1) had superior adherence and NV rates, despite involving a slightly higher risk population (younger and/or female). Conclusions: According to HEC antiemetic guidelines, NK1 RA use should occur independent of 5HT3 RA agent selection. However, we observed less NK1 RA use where OND was preferred, which may have caused the observed higher rates of NV with OND. Further evaluation should assess whether pharmacy cost minimization is a driver of both OND preference and NK1 omission in HEC. [Table: see text]

Aggressiveness of care and overall survival in young metastatic colorectal cancer patients

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Background: Colorectal cancer (CRC) incidence in patients younger than 50 years of age is steadily rising by 2% annually. Early-onset CRC usually presents with more aggressive features; however, data on prognosis are widely conflicting. Clinicians may hold an age-related bias in treating younger patients, but this proclivity and its effects have not been quantified. Methods: Patients with a history of metastatic CRC who consented to a departmental chart review protocol were collected between 2014 and 2018 at Massachusetts General Hospital. The cohort was divided into two groups based on age at initial diagnosis: < 50 and ≥50. Data were gathered on treatments and clinicopathological features. A log-rank test compared survival from the diagnosis of metastatic disease between age groups. The distributions of clinicopathological features were compared using Wilcoxon rank sum tests. Results: 464 metastatic CRC patients were identified. 155 patients (33%) were < 50 (median age 43, 49% female) and 309 patients (67%) were ≥50 (median age 61, 45% female). Sex did not significantly differ between the two groups (p = 0.45). Patients < 50 received more lines of therapy after metastatic diagnosis than patients ≥50 (mean 2.7 v. 2.2; p = 0.002). Younger patients also received more resections of distant metastases (mean 0.62 v. 0.48; p = 0.01). A higher rate of enrollment in clinical trials for patients < 50 approached significance (p = 0.06). Even so, patients < 50 did not see a significant survival benefit over older patients (2/5-year survival from metastatic diagnosis 77%/47% v. 73%/38%, p = 0.23). Patients < 50 had a lower proportion of right-sided tumors (p = 0.0002) and BRAF mutations (p = 0.0009). There was no difference in MSI status (p = 0.28), RAS mutational status (p = 0.40), mucinous features (p = 0.53), or signet ring features (p = 0.26). Conclusions: Overall survival in patients < 50 is similar to patients ≥50, despite patients < 50 receiving more aggressive therapy. Further study is warranted to better understand these differences. Potential areas of interest include performance status, age-related treatment bias, and biological factors.

The Cambia Sojourns Scholars Leadership Program: Projects and Reflections on Leadership in Palliative Care

Background: Effective leadership is necessary to meet the complex care needs of patients with serious, life-limiting illness. The Cambia Health Foundation Sojourns Scholars Program is advancing leadership in palliative care through supporting emerging leaders. The 2016 Cohort has implemented a range of projects to promote their leadership development. Objective: To describe the leadership themes emerging from individual project implementation of the 2016 Sojourns Leadership. Methods: We summarize the synthesized leadership themes derived from both remote and in-person meetings and written reflections of the 2016 Cambia Sojourn Leadership Cohort. Results: The 2016 Cambia Sojourn Leadership Scholar Cohort projects are described. We identified three leadership themes related to palliative care initiatives: openness and flexibility, partnership and team building, and leveraging expertise and risk. Discussion: Unprecedented challenges in a rapidly changing health environment demand palliative care leadership to influence care quality, delivery, policy, and clinical care. Flexibility and openness; partnership and team building; and expertise to implement change emerged as critical themes to advancing the care of patients with serious, life-limiting illness. These leadership themes are consistent with both previous Cambia Sojourns Scholar cohorts and the literature, are essential for the next generation of leaders to implement new models of quality palliative care, payment for palliative care, and education for patients, caregivers, and health care providers. Conclusion: In order to design and implement quality palliative care, leadership development is essential. Use of flexibility and openness; partnership and team building; and expertise to implement change are important themes for success. Whether through the Cambia Health Foundation Sojourns Leadership Program or opportunities within professional organizations, cultivation of the next generation of leaders is critical.

Potentially avoidable acute care use among patients receiving oxaliplatin

651

Background: Oxaliplatin (OX), used primarily in gastrointestinal cancers, is considered moderately emetogenic while multiple guidelines classify carboplatin and cisplatin as highly emetogenic chemotherapy (HEC). The new oncology outcome measure (OP-35) from the US Centers for Medicare and Medicaid Services (CMS) deems 30-day post-chemotherapy inpatient (IP) and emergency room (ED) events “potentially avoidable” if involving nausea or emesis (NV) or any of eight other toxicities. We lack data comparing avoidable IP/ED and NV events for OX relative to platinums classified as HEC. Methods: We assessed OX, cisplatin, and carboplatin courses of therapy from 4Q 2012 to 1Q 2018 using the IBM Watson Explorys database. We identified IP/ED and OP-35 toxicities (anemia, dehydration, diarrhea, fever, NV, neutropenia, pain, pneumonia, or sepsis) by diagnosis and procedure codes, and stratified results by sex and age < 70 (median age at diagnosis for colorectal cancer). An IP/ED event could involve ≥ 1 OP-35 toxicity. We also evaluated a FOLFIRINOX subgroup (receiving irinotecan ≤ 3 days after OX). Results: In sum, we identified 4,231 OX courses (382 FOLFIRINOX) (Table). OP-35 toxicities occurred in 75% of IP/ED events; of these, 34% OX and 42% FOLFIRINOX involved NV. Rates of IP/ED, IP/ED OP-35-defined toxicity, and NV after OX were consistent with cisplatin and carboplatin. Among patients receiving OX, women age < 70 (n = 1388) had higher NV rates vs. others (p < 0.001). Conclusions: Roughly one-third of patients receiving OX experienced IP/ED events ≤ 30 days post chemotherapy. Most involved ≥ 1 of 10 OP-35 toxicities, meeting CMS’ criteria as potentially avoidable acute care. OX IP/ED rates and NV rates were similar to other platinums and were worse among women age < 70, suggesting more aggressive antiemetic prophylaxis should be evaluated. [Table: see text]

Inpatient hospitalization costs associated with nausea and vomiting among patients with cancer

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Background: Reducing hospitalizations for chemotherapy-related toxicities represents an opportunity to improve both the quality and cost of cancer treatment. Nausea and vomiting (NV) account for almost 10% of “avoidable” toxicity-related post-chemotherapy hospitalizations (2016 Medicare data). We sought to evaluate the event cost of NV-related hospitalizations among patients with cancer from a US payer perspective. Methods: From a large US claims database (Truven MarketScan), we identified hospitalizations with NV as the primary diagnosis and cancer as a secondary diagnosis (01/2011-06/2017). This method increases specificity for NV as the principal hospitalization factor, while underreporting the prevalence of NV as a contributory factor. To determine event costs, we evaluated hospital and other reimbursement during the hospitalization. To explore subgroup differences, we stratified results by tumor type, payer type, admission route, receipt of highly emetogenic chemotherapy (HEC; 2017 definition includes carboplatin AUC ≥4) and antiemetic prophylaxis. We adjusted all costs to 2017 US dollars. Results: Among 918,192 hospitalizations involving cancer, we identified 80,995 with both NV and a cancer diagnosis code. Of these, 5,293 had NV as the primary diagnosis and 62 lacked cost data. Patients (mean age = 57.7±16.2) were 67% female. Median hospital length of stay was 4 days and mean cost per hospitalization was $15,085. Non-Medicare admissions (82%) had a higher mean cost vs. Medicare ($15,737 vs. $12,111, p < 0.01). We found < $1,000 difference between the highest and lowest cost per hospitalization among the 6 most common tumor types. We found the 65% of patients with a chemotherapy claim ≤30 days prior to hospitalization had costs of $13,882 per event. Among the 45% of chemotherapies that were HEC, > 50% lacked an NK1 receptor antagonist as prophylaxis. Conclusions: The average cost of NV-related hospitalizations among patients with cancer exceeds $15,000 per event, highlighting the need to effectively address this symptom. Roughly half the hospitalizations involved HEC, with over half of those patients not receiving guideline-based antiemetic prophylaxis.