Citations

Abstract Background Colon cancer (CC) incidence in young adults (age 20-49 years), termed early-onset CC (EO-CC), is increasing. Methods Individual patient data on 35 713 subjects with stage III colon cancer from 25 randomized studies in the Adjuvant Colon Cancer ENdpoint database were pooled. The distributions of demographics, clinicopathological features, biomarker status, and outcome data were summarized by age group. Overall survival, disease-free survival, time to recurrence, and survival after recurrence were assessed by Kaplan-Meier curves and Cox models stratified by treatment arms within studies, adjusting for sex, race, body mass index, performance status, disease stage, grade, risk group, number of lymph nodes examined, disease sidedness, and molecular markers. All statistical tests were 2-sided. Results Using a 5% difference between age groups as the clinically meaningful cutoff, patients with stage III EO-CC had similar sex, race, performance status, risk group, tumor sidedness, and T stage compared with patients with late-onset CC (age 50 years and older). EO-CC patients were less likely to be overweight (30.2% vs 36.2%) and more commonly had 12 or more lymph nodes resected (69.5% vs 58.7%). EO-CC tumors were more frequently mismatch repair deficient (16.4% vs 11.5%) and less likely to have BRAFV600E (5.6% vs 14.0%), suggesting a higher rate of Lynch syndrome in EO-CC. Patients with EO-CC had statistically significantly better overall survival (hazard ratio [HR] = 0.81, 95% confidence interval [CI] = 0.74 to 0.89; P < .001), disease-free survival (HR = 0.91, 95% CI = 0.84 to 0.98; P = .01), and survival after recurrence (HR = 0.88, 95% CI = 0.80 to 0.97; P = .008) in the analysis without molecular markers; however, age at onset of CC lost its prognostic value when outcome was adjusted for molecular markers. Conclusion Tumor biology was found to be a more important prognostic factor than age of onset among stage III colon cancer patients in the Adjuvant Colon Cancer ENdpoint database.

3610 Background: Chronic lower grade adverse events (AE) can negatively affect a patient’s quality of life but it is difficult to capture using a traditional toxicity reporting approach. A novel AE reporting method was recently developed to describe, summarize, and present longitudinal AE profiles(Lopes et al, 2021). We leveraged this method to describe and compare the AE profiles of doublet chemotherapy (DC) + Cetuximab and DC alone in mCRC patients. Methods: This AE reporting method utilizes two additional AE metrics to complement the maximum (max) toxicity grade usually reported in clinical trials. Onset time indicates the time period in which max grade for an AE occurred for the first time, defined here as “early” (i.e. within first 42 days) and “late” (i.e. after the 42nd day). AE Load (AEL) indicates the overall severity of an AE in the entire treatment. AEL varies from 0 to 1. Higher AEL indicates a worse overall severity of that AE over time. AEL is the key metric for describing chronic AE. We included patients receiving DC + cetuximab (n = 738) and DC alone (n = 564 [ref group]) from two randomized first-line trials in the ARCAD database. Diarrhea, rash, hand-foot syndrome (HFS), fatigue, anorexia, and mucositis were examined and adjusted for backbone (FOLFOX vs. FOLFIRI), ECOG PS, sex, site location, dose reduction, and treatment length. Results: For rash, DC + cetuximab had a higher risk of G3+ (21% vs. 0.5%; odds ratio {OR} [95% confidence interval {CI}] = 50 [16,157], p < 0.001), increased overall severity over the entire treatment (AEL = 0.257 vs. 0.069; Adjusted difference in means–Mdiff [95% CI] = 0.22 [0.21,0.23], p < 0.001), and increased risk of early onset (67% vs. 33%; OR [95% CI] = 4.3 [2.7,6.7], p < 0.001). DC + cetuximab also had higher AEL for rash across max grades (p < 0.001 within G1, G2, and G3+). For HFS, DC + cetuximab had a higher risk of G3+ (OR [95% CI] = 6.0 [2.5,14], p < 0.001), increased overall severity (AEL = 0.139 vs. 0.087; Mdiff [95% CI] = 0.03 [0.03,0.04], p < 0.001), and slightly earlier onset (12.4 vs. 13.9 weeks; Mdiff, weeks [95% CI] = -4.9 [-0.80,-9.0], p = 0.021). Within each max grade, DC + cetuximab did not have higher AEL of HFS. No associations were found for diarrhea, fatigue, anorexia, or mucositis. Conclusions: The addition of cetuximab is associated with higher grade, more persistent, and more immediate rash. The higher severity in HFS with the addition of cetuximab appears to be related to higher grade but not chronic HFS. This method may be useful to describe different strategies, e.g. intermittent cetuximab. It provided a comprehensive view of acute and chronic toxicity profiles supporting its potential interest as new metrics in clinical trials. Lopes GS, Tournigand C, Olswold CL, et al. Adverse event load, onset, and maximum grade: A novel method of reporting adverse events in cancer clinical trials. Clinical Trials. 2021;18(1):51-60

3597 Background: Colon cancer (CC) incidence and mortality have decreased since the 1970s, but the incidence in young adults (20-49 years) is increasing. There are limited data suggesting that, as a group, patients with early onset CRC (eoCC) may have different phenotypic characteristics compared to those with late onset CRC (loCC, age ≥ 50 years). Methods: Individual patient data on 35,713 subjects with stage III CC from 25 randomized studies (recruiting between 1987 and 2009) in the ACCENT database were pooled. The distributions of demographics, clinicopathological features, biomarkers, and outcome data were summarized by age group. Overall survival (OS), disease-free survival (DFS), recurrence free rate (RFR), and survival after recurrence (SAR) were assessed by Kaplan-Meier curves and Cox models stratified by treatment arms within studies, adjusting for gender, race, body mass index, performance status, disease stage, grade, risk group, number of lymph nodes examined, disease sidedness and molecular markers. Results: Using a 5% difference between age groups as the clinically meaningful cutoff, patients with stage III eoCC (n = 6246) had similar distributions according to gender, race, PS, risk group, tumor sidedness and T/N stage compared to those with loCC (n = 29467). Patients with eoCC were significantly less likely to be overweight (30.2% vs 36.2%) but more commonly had ≥ 12 lymph nodes resected (69.5% vs 58.7%). The eoCC tumors were more frequently mismatch repair deficient (16.4% vs 11.5%), and less likely to have BRAFV600E (5.6% vs 14.0%), suggesting a higher frequency of Lynch syndrome in eoCC. In univariate analysis, patients with stage III eoCC had significantly better OS, DFS, and SAR; the difference between 3-year DFS and RFR strongly suggests the OS/DFS difference between these the eoCC and loCC may be due to increased competing risks and comorbidities in patients with loCC. In multivariate analysis, age at onset lost its prognostic value when outcome was adjusted for molecular markers. The clear relation between age of onset and KRAS/BRAF status was confirmed in the interaction analysis. Conclusions: Tumor biology was an important determinant of prognosis regardless of patient age. In multivariate analysis age of onset was not a statistically significant determinant of outcome.[Table: see text]

3591 Background: Adiponectin is a peptide hormone exclusively secreted by adipocytes that plays a role in immune regulation and in the host inflammatory response to cancer. We examined postsurgical adiponectin levels in relationship to tumor infiltrating lymphocytes (TILs), clinicopathological features, vitamin D status, and patient survival in participants in a phase 3 trial of adjuvant chemotherapy. Methods: Plasma adiponectin and 25-hydroxyvitamin D [25(OH)D] were analyzed by radioimmunoassay in 600 patients with stage III colon carcinoma who received adjuvant FOLFOX +/- cetuximab. TIL densities were determined at light microscopy in routine histopathological sections. The associations between adiponectin and 25(OH)D, TILs, other factors were evaluated by Fisher’s Exact, Chi-squared, t-test, and Kruskal-Wallis tests where appropriate. The association between adiponectin or 25(OH)D with disease-free survival (DFS), time to recurrence (TTR) and overall survival (OS) were evaluated by multivariable Cox regression, adjusting for body mass index (BMI), race, T, N stage, performance status, tumor location, TILs, BRAF/KRAS, and mismatch repair status. Results: A statistically significant and inverse association between adiponectin level and BMI was observed with lower levels found with obesity (BMI > 30 kg/m2) [p < 0.001]. The level of adiponectin was significantly lower in men vs women (p < 0.001), in blacks vs whites or Asians (p < 0.032), and in patients with fewer regional lymph node metastases (N1 vs N2 stage, p = 0.011). A significantly lower level of adiponectin was found in patients whose tumors had high vs low TIL densities (p = 0.040), but was unrelated to 25(OH)D. Insufficiency of 25(OH)D ( < 30 ng/ml) was detected in 291 (49%) of patients and was not associated with TILs. By multivariable analysis, adiponectin was not associated significantly with patient DFS (HRadj= 0.98, 95% CI 0.74-1.29, padj= 0.88) nor with OS nor time-to-recurrence (TTR). TIL densities were significantly prognostic, but 25(OH)D was not (DFS: HRadj= 1.12, 95% CI 0.85-1.47, padj= 0.44). No significant interaction was observed for adiponectin with TILs for the association with DFS. Conclusions: Lower adiponectin levels were associated with significantly increased TIL densities in colon cancers, indicating an enhanced anti-tumor immune response. In contrast to TILs, adiponectin was not independently associated with patient outcome. Nearly one-half of stage III patients were vitamin D insufficient, although 25(OH)D was not prognostic.

3575 Background: Pts with mCRC frequently receive ≥1 sequential treatment TL. Approximately 50%-60% of pts receive second-line (L2) and 20%-30% third-line (L3) regimens in routine practice. We investigated the pts clinical/tumor characteristics and their prognostic impact across TL. Methods: Data from 37,560 pts enrolled in 48 randomized trials (34 in first (L1), 9 in L2, and 5 in L3) were analyzed. Candidate variables (VAR) measured at enrollment were sex, age, body mass index, performance status (PS), bilirubin, hemoglobin (Hb), platelets (Pl), derived white blood cells-to-absolute neutrophil counts ratio (WBC/ANC), lactate dehydrogenase (LDH), alkaline phosphatase (ALP), primary tumor location, and number and location of metastatic sites (MS). Missing data were imputed. VAR with significant value at all TL were selected to construct a prognostic score of overall survival (OS) in training set (TS, n=30,050; 80%). For each TL, the score was calculated as the sum on the estimations of the VAR’ coefficients from the common multivariate model; Cox’s model was used to define risk groups. The discrimination capability was assessed using the Harrell’s C-index. External validation was done in the validation set (VS, n=7,510; 20%). Results: A total of 26,974 pts in L1, 7,693 pts in L2 and 2,893 pts in L3 were analyzed. The following characteristics increased continuously over TL: ≥2 MS (57%, 72%, 82%), lung metastases (50%, 74%, 91%), lymph nodes metastases (51%, 61%, 80%), KRAS mutation (37%, 47%, 51%) and elevated ALP (46%, 52%, 61%). BRAF mutation decreased (9%, 7%, 5%). In L1 vs L3 trials, 70% vs 89% of patients had primary tumor resection, 10% vs 80% had at least one metastasectomy and 31% vs 78% had a late metachronous (>12 months) metastasis. 7 independent VAR were retained in the prognostic score (PS, Hb, Pl, WBC/ANC, LDH, ALP, and the number of MS); four pt groups with significantly different prognoses were defined (table). This score remained valid when excluding pts with PS 2. Third-line oral drugs (vs placebo) and subsequent line (L2/L1 or L3/L2) were effective in all prognostic groups. Conclusions: Clinical/tumor pt characteristics significantly varied over subsequent TL in patients included in randomized trials. The same prognostic model using practical clinical and biological variables can be used in all TL.[Table: see text]

3517 Background: Incidence of early-onset colorectal cancer (eoCRC, age < 50) is steadily increasing. Decisions on adjuvant treatment (adjTx) regimen and duration should consider tx adherence, toxicity (tox) and expected outcomes in a population with life-expectancy longer than late onset CRC (loCRC, age ≥ 50). Methods: Individual patient data from stage II/III patients (pts) from 6 randomised trials in the IDEA database were used to compare characteristics, tx adherence, and adverse events of eoCRC to loCRC. To reduce the confounder of non-cancer-related deaths due to age/co-morbidities, time-to-recurrence (TTR) and cancer-specific survival (CSS) were compared by stratified Gay k-sample test. 5-year cancer-specific mortality (CSM) rate were estimated by adjusted cumulative incidence function. 3-year relapse-free survival (RFS) rate were compared by stratified and adjusted COX models. Results: Out of 16,349 pts included, 1564 (9.6%) were eoCRC. Compared to loCRC, eoCRC had lower percent of male pts (51% vs 57%, p < 0.01) better performance status (PS0 86% vs 80%, p < 0.01), similar T stage distribution (% T1-3/T4: 76/24 vs 77/23, p = 0.97), higher rate of N2 disease (24% vs 22%, p < 0.01), more likely to complete pre-planned duration of adjTx (83.2% vs 78.2%, p < 0.01) and received a higher tx intensity especially with 6 month tx (mean oxaliplatin dose intensity 75% vs 72%, p < 0.01; capecitabine 85% vs 78%, p < 0.01; 5FU 85% vs 82% p < 0.01). Gastrointestinal tox was more common in eoCRC (any grade nausea 58% vs 45%, p < 0.01; any grade vomiting 22% vs 16%, p < 0.01); haematological tox was more frequent in loCRC (62% vs, 69%, p = < 0.01); any grade neuropathy rate was similar (75%). Significant interaction was found between age and T stage for TTR (p = 0.04). Clinical outcome estimates and comparisons are shown in Table. Notably, high risk stage III (T4/N2) eoCRC had significantly lower 3-y RFS rate (54% vs 64%, HRadj 0.74, p < 0.01). Conclusions: eoCRC have better tx adherence than loCRC, as expected. While in high risk stage II and low risk stage III, cancer-specific outcomes are not different, in high risk stage III young age is negatively prognostic and associated with significantly higher relapse rate and risk of CRC death; this is despite a higher administered adjTx-intensity, suggesting a more aggressive disease biology. Clinical trial information: NCT00749450 (SCOT); NCT00646607 (TOSCA); NCT01150045 (CALGB/SWOG 80702); NCT00958737 (IDEA France) [Table: see text]

Abstract Background Unplanned subgroup analyses from several studies have suggested primary tumor sidedness (PTS) as a potential prognostic and predictive parameter in metastatic colorectal cancer (mCRC). We aimed to investigate the impact of PTS on outcomes of mCRC patients. Methods PTS data of 9277 mCRC patients from 12 first-line randomized trials in the ARCAD database were pooled. Overall survival (OS) and progression-free survival (PFS) were assessed using Kaplan-Meier and Cox models adjusting for age, sex, performance status, prior radiation/chemotherapy, and stratified by treatment arm. Predictive value was tested by interaction term between PTS and treatment (cetuximab plus chemotherapy vs chemotherapy alone). All statistical tests were 2-sided. Results Compared with right-sided metastatic colorectal cancer patients (n = 2421, 26.1%), left-sided metastatic colorectal cancer patients (n = 6856, 73.9%) had better OS (median = 21.6 vs 15.9 months; adjusted hazard ratio [HRadj] = 0.71, 95% confidence interval [CI] = 0.67 to 0.76; P &lt; .001) and PFS (median = 8.6 vs 7.5 months; HRadj = 0.80, 95% CI = 0.75 to 0.84; P &lt; .001). Interaction between PTS and KRAS mutation was statistically significant (Pinteraction &lt; .001); left-sidedness was associated with better prognosis among KRAS wild-type (WT) (OS HRadj = 0.59, 95% CI = 0.53 to 0.66; PFS HRadj =0.68, 95% CI = 0.61 to 0.75) but not among KRAS mutated tumors. Among KRAS-WT tumors, survival benefit from anti-EGFR was confirmed for left-sidedness (OS HRadj = 0.85, 95% CI = 0.75 to 0.97; P = .01; PFS HRadj = 0.77, 95% CI = 0.67 to 0.88; P &lt; .001) but not for right-sidedness. Conclusions The prognostic value of PTS is restricted to the KRAS-WT population. PTS is predictive of anti-EGFR efficacy, with a statistically significant improvement of survival for left-sidedness mCRC patients. These results suggest treatment choice in mCRC should be based on both PTS and KRAS status.

Abstract Background: A positive association between circulating C-reactive protein (CRP) and colorectal cancer survival was reported in observational studies, which are susceptible to unmeasured confounding and reverse causality. We used a Mendelian randomization approach to evaluate the association between genetically predicted CRP concentrations and colorectal cancer–specific survival. Methods: We used individual-level data for 16,918 eligible colorectal cancer cases of European ancestry from 15 studies within the International Survival Analysis of Colorectal Cancer Consortium. We calculated a genetic-risk score based on 52 CRP-associated genetic variants identified from genome-wide association studies. Because of the non-collapsibility of hazard ratios from Cox proportional hazards models, we used the additive hazards model to calculate hazard differences (HD) and 95% confidence intervals (CI) for the association between genetically predicted CRP concentrations and colorectal cancer–specific survival, overall and by stage at diagnosis and tumor location. Analyses were adjusted for age at diagnosis, sex, body mass index, genotyping platform, study, and principal components. Results: Of the 5,395 (32%) deaths accrued over up to 10 years of follow-up, 3,808 (23%) were due to colorectal cancer. Genetically predicted CRP concentration was not associated with colorectal cancer–specific survival (HD, −1.15; 95% CI, −2.76 to 0.47 per 100,000 person-years; P = 0.16). Similarly, no associations were observed in subgroup analyses by stage at diagnosis or tumor location. Conclusions: Despite adequate power to detect moderate associations, our results did not support a causal effect of circulating CRP concentrations on colorectal cancer–specific survival. Impact: Future research evaluating genetically determined levels of other circulating inflammatory biomarkers (i.e., IL6) with colorectal cancer survival outcomes is needed.

Given the Food and Drug Administration's (FDA's) acceptance of master protocol designs in recent guidance documents, the oncology field is rapidly moving to address the paradigm shift to molecular subtype focused studies. Identifying new “marker‐based” treatments requires new methodologies to address the growing demand to conduct clinical trials in smaller molecular subpopulations, identify effective treatment and marker interactions, and control for false positives. We introduce our methodology, Hierarchical Bayesian Clustering Design of Multiple Biomarker Subgroups (HCOMBS), a two‐stage umbrella Phase II design with effect size clustering and information borrowing across multiple biomarker‐treatment pairs. HCOMBS was designed to reduce required sample size, differentiate between varying effect sizes, and control for operating characteristics in the multi‐arm setting. When compared to independently applied Simon's Optimal two‐stage design, we showed through simulations that HCOMBS required less participants per treatment arm with a well‐controlled family‐wise error rate and desirable marginal power. Additionally, HCOMBS features a statistical approach that simultaneously conducts clustering and hypothesis testing in one step. We also applied the proposed design on the alliance brain metastases umbrella trial.