Mayer, Robert J.

Abstract Background: In non-metastatic colorectal cancer, a body mass index (BMI) paradox is observed where overweight and early obese patients experience improved outcomes compared to patients with normal, low, or morbidly obese BMI. The influence of obesity on patients with advanced or metastatic colorectal cancer (mCRC) is relatively unexplored. Methods: We conducted a prospective BMI companion study in CALGB (now Alliance for Clinical Trials in Oncology)/SWOG 80405, a phase III mCRC treatment trial. BMI was measured at trial registration. Primary and secondary endpoints were overall and progression-free survival, respectively. To minimize confounding by poor and rapidly declining health, we used Cox proportional hazards regression to adjust for known prognostic factors, comorbidities, physical activity, and weight loss, and excluded individuals with low BMI <21 from statistical tests for trend. We also examined self-reported weight loss over the six months prior to trial enrollment as an independent predictor of patient outcome. Results: In this sub-study of a phase III mCRC trial, BMI was recorded for all 2,323 patients enrolled. Following adjustment for confounders, there were no significant associations between BMI and overall or progression-free survival (excluding BMI <21, Ptrend with increasing BMI = 0.12 and 0.42, respectively). Conversely, weight loss prior to treatment was associated with shorter overall and progression-free survival; compared to individuals with weight change <5%, individuals with weight loss >20% experienced an adjusted hazard ratio of 1.46 for all-cause mortality (95% confidence interval 1.15 to 1.85, Ptrend <.0001) and of 1.27 for disease progression or death (95% confidence interval 1.04 to 1.56, Ptrend = .009). Conclusion: In this prospective study of patients with mCRC, BMI at time of first-line chemotherapy initiation was not associated with patient outcome. Weight loss prior to study entry was associated with increased risk of patient mortality and disease progression. Citation Format: Brendan Guercio, Sui Zhang, Alan P. Venook, Fang-Shu Ou, Donna Niedzwiecki, Heinz-Josef Lenz, Federico Innocenti, Hanna Sanoff, Michelle R. Mahoney, Bert H. O'Neil, James E. Shaw, Blase N. Polite, Howard S. Hochster, James N. Atkins, Richard M. Goldberg, Robert J. Mayer, Charles D. Blanke, Charles S. Fuchs, Jeffrey A. Meyerhardt. Body mass index, weight loss, and progression and mortality in metastatic colorectal cancer: Results from CALGB/SWOG 80405 (Alliance) [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 3285.

3035 Background: Energy balance-associated biomarkers such as insulin-like growth factors (IGFs) and IGF-binding proteins (IGFBPs) have been associated with risk and prognosis of various malignancies. Their relationship to disease progression and mortality in metastatic colorectal cancer (mCRC) requires further study. Methods: In a prospective cohort study, baseline plasma IGFBP-3, IGFBP-7, C-peptide, IGF-I, and adiponectin were measured at trial registration among 1,086 patients participating in a National Cancer Institute-sponsored clinical trial of first-line therapy for mCRC. We used Cox proportional hazards regression to adjust for confounders and examine associations of biomarkers with overall (OS) and progression-free survival (PFS). Results: Higher plasma IGFBP-3 was associated with longer OS (adjusted Ptrend < .001) and PFS (adjusted Ptrend = .003). Compared to patients in the lowest IGFBP-3 quintile, patients in the highest quintile experienced an adjusted HR for all-cause mortality of 0.58 (95% CI 0.42 to 0.78) and for disease progression or mortality of 0.60 (95% CI 0.45 to 0.82). Higher plasma IGFBP-7 was associated with shorter OS (adjusted Ptrend < .001) and PFS (adjusted Ptrend = .02). Compared to patients in the lowest IGFBP-7 quintile, patients in the highest quintile experienced an adjusted HR for all-cause mortality of 1.52 (95% CI 1.24 to 1.88) and for disease progression or mortality of 1.28 (95% CI 1.05 to 1.57). C-peptide and IGF-I were not significantly associated with patient outcomes (adjusted Ptrend = .73 and .30 for OS). Adiponectin was not associated with OS; there was a U shaped association between adiponectin and PFS, wherein low and high values were associated with shorter PFS ( Pnon-linear trend = .03). Conclusions: In patients with mCRC, high plasma IGFBP-3 and low IGFBP-7 were associated with reduced risk of disease progression and mortality. These data suggest that energy-balance associated biomarkers may offer prognostic and biologic insights into mCRC. Support: U10CA180821, U10CA180882, BMS, Genentech, Pfizer, Sanofi; https://acknowledgments.alliancefound.org .

PURPOSETo determine the predictive and prognostic value of the consensus molecular subtypes (CMSs) of colorectal cancer (CRC) that represent a merging of gene expression–based features largely in primary tumors from six independent classification systems and provide a framework for capturing the intrinsic heterogeneity of CRC in patients enrolled in CALGB/SWOG 80405.PATIENTS AND METHODSCALGB/SWOG 80405 is a phase III trial that compared the addition of bevacizumab or cetuximab to infusional fluorouracil, leucovorin, and oxaliplatin or fluorouracil, leucovorin, and irinotecan as first-line treatment of advanced CRC. We characterized the CMS classification using a novel NanoString gene expression panel on primary CRCs from 581 patients enrolled in this study to assess the prognostic and predictive value of CMSs in these patients.RESULTSThe CMSs are highly prognostic for overall survival (OS; P < .001) and progression-free survival (PFS; P < .001). Furthermore, CMSs were predictive for both OS ( P for interaction < .001) and PFS ( P for interaction = .0032). In the CMS1 cohort, patients treated with bevacizumab had a significantly longer OS than those treated with cetuximab ( P < .001). In the CMS2 cohort, patients treated with cetuximab had a significantly longer OS than patients treated with bevacizumab ( P = .0046).CONCLUSIONThese findings highlight the possible clinical utility of CMSs and suggests that refinement of the CMS classification may provide a path toward identifying patients with metastatic CRC who are most likely to benefit from specific targeted therapy as part of the initial treatment.

752 Background: Elderly patients (≥65 yrs) with metastatic colorectal cancer (mCRC) are more likely to have comorbid conditions than younger patients ( < 65 yrs), limiting their therapeutic options. As previously reported (Mayer et al. J Clin Oncol 2017;35:abs 3559), FTD/TPI confirmed its clinical profile in mCRC in a real-world setting. Here, we report the safety and tolerability profile of FTD/TPI from the expanded-access program (EAP) in patients aged ≥65 yrs. Methods: Patients (≥18 yrs) with mCRC following ≥2 regimens of anticancer therapy and an Eastern Cooperative Oncology Group performance status of 0 or 1 were enrolled to this open-label EAP. Patients received FTD/TPI 35 mg/m2 twice daily for 5 days followed by 2 days’ rest for 2 weeks, with a 14-day rest period (28-day treatment cycle). Data were collected for therapy duration, treatment discontinuation, and adverse events (AEs). Results: Of 549 patients, 377 (68.7%) were aged < 65 and 172 (31.3%) were ≥65. The treatment duration of FTD/TPI was similar between < 65 and ≥65 yrs (Table). A lower proportion of those aged ≥65 had fatigue and nausea compared with < 65 (Table). However, the frequency of neutropenia and diarrhea was slightly increased in those ≥65 compared with < 65 (Table). One patient (0.6%) in the ≥65 group developed febrile neutropenia compared with 9 (2.4%) in the < 65 group, with no associated deaths in either group. Conclusions: This analysis from the EAP showed that the safety profile and treatment duration of FTD/TPI in patients aged ≥65 with mCRC were similar to those in patients aged < 65. FTD/TPI is well tolerated and can be considered in patients aged ≥65 with mCRC. Clinical trial information: NCT-02286492. [Table: see text]

638 Background: Colorectal cancer (CRC) is a heterogeneous disease with distinct molecular subtypes in part based on RAS mutational status. It is plausible that RAS mutations are differentially distributed between CC and AA and may contribute to poor outcomes in AAs with CRC. Methods: We did a retrospective analysis of CALGB/SWOG 80405 trial patients. We divided the entire cohort into 2 groups: a) Common RAS: mutation in KRAS exon 2, codon 12 or 13; b) Extended RAS: any NRAS mutations or mutation in KRAS except those listed above. We then analyzed these two subgroups for association between RAS mutations and race (3 categories: Caucasian, AA, Others) using chi-square test for univariate analyses and logistic regression for multivariate analysis. We also analyzed the effect of extended RAS testing on prognosis of metastatic CRC by estimating the overall survival (OS) using Kaplan-Meier method and 95% confidence interval (CI). Cox proportional-hazard model was used for multivariate analyses. Results: There were 1729 CRC patients in common RAS group of which 357 (20.6%) had mutations present. Extended RAS group had 621 patients of which 95 (15.5%) had mutations present. There was no significant difference in the rate of common RAS mutations between CC and AA (20.5% vs. 24%, p=0.22). However, extended RAS mutations were significantly more in AA as compared to CC (25% vs. 14%, p=0.02). Multivariate analysis adjusted for age, gender, prior adjuvant chemotherapy and pelvic radiation confirmed higher odds of extended RAS mutation in AA compared to CC (adjusted OR 1.12; 95% CI 1.01-1.23; p=0.02). The median OS in patients with an extended RAS mutation was shorter as compared to those without extended RAS mutation (25.3 vs. 31.9 months; HR 1.26; 95% CI 0.99-1.62; p=0.05). Multivariate analyses adjusted for age, gender, race, prior adjuvant chemotherapy and pelvic radiation showed a trend towards longer OS in patients without extended RAS mutation as compared those with extended RAS mutation (adjusted HR= 1.24, 95% CI, 0.97-0.1.58, p=0.08). Conclusions: Extended RAS mutations are significantly more common in AA as compared to CC. Additionally, presence of extended RAS mutation may confer a poor prognosis in CRC patients.

3559 Background: A Phase 3 clinical trial (RECOURSE) showed that trifluridine/tipiracil (FTD/TPI) was effective in the treatment of refractory metastatic colorectal cancer (mCRC) treated with standard chemotherapy and targeted-therapy drugs (Mayer et al. N Engl J Med 2015;372:1909-19). An expanded-access program (EAP) was started to provide access to FTD/TPI for patients with mCRC with similar eligibility and to further assess the safety of FTD/TPI in a “real-world” setting in US patients. Methods: Patients aged ≥18 years with refractory mCRC resistant to ≥2 regimens of standard chemotherapy with appropriate biologics and an Eastern Cooperative Oncology Group performance status of 0 or 1 were enrolled to this open-label EAP. Patients received FTD/TPI 35 mg/m2twice daily for 5 days followed by 2 days’ rest repeated twice followed by 14 days’ rest over a 28-day treatment cycle until drug discontinuation. Sites reported duration of therapy, discontinuation due to disease progression, and adverse events (AEs) for each patient. Results: 549 patients were enrolled; 53.2% were male. Median duration of FTD/TPI therapy was 9.7 weeks, which was similar to US patients from RECOURSE (8.9). 10.2% of patients died during the study period, 9.7% due to disease progression. 76.1% of patients discontinued treatment due to disease progression and 4% discontinued due to AEs. Drug-related clinically significant AEs (all grades) are summarized in the table. Conclusions: Patients with refractory mCRC in this EAP had a similar exposure duration to that reported in US patients from RECOURSE, with no unexpected safety concerns. While gastrointestinal toxicity was lower in this population, this may be due to reporting of “significant” events. The clinical profile of FTD/TPI is confirmed in this larger, non-randomized “real-world” experience. Sponsorship: Taiho Oncology, Inc. Editorial Assistance: Complete HealthVizion. Clinical trial information: NCT02286492. [Table: see text]

3511 Background: CALGB 80405 was a randomized Ph3 trial showing no OS or PFS difference in mCRC pts treated with Bevacizumab (BV) or Cetuximab (Cet) in the first line. A Nanostring platform was used to determine the CMS classification of 392 KRAS wt (codon 12 and 13) primary tumors and correlated it with OS and PFS in patients enrolled in 80405. Methods: CMS for 392 of 431tumors were defined using a custom CRC Nanostring panel (39 CMS classification not possible). Stratified Cox proportional hazard model was used to evaluate the effect of CMS classification stratified by prior radiation, prior chemotherapy, adjusting for age, sex, race, primary in place, liver met only, and sidedness. Results: We found CMS1 (14%), CMS2 (47%), CMS3 (2%), CMS4 (29%), NonConsensus (8%). Results are shown in Table 1. Patients with CMS1 who received BV had significantly longer OS than those who received Cet (HR 0.47, 95% CI [0.24, 0.92]). Patients with CMS2 who received BV tended to have shorter OS than those who received Cet (HR 1.41, CI [0.95, 2.08]). Conclusions: Our data suggest that CMS is associated with OS and PFS in first line therapy in mCRC patients. Preliminary data suggest that certain CMS may be associated with efficacy of Bev and Cet based chemotherapy. CMS classification should be explored as a stratification factor in future trials. Support: U10CA180821, U10CA180830, U10CA180882 Clinical trial information: NCT00265850. [Table: see text]