Citations

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]

1561 Background: Surgical interventions are studied less often than medical or radiation interventions in oncology clinical trials. We characterized surgical oncology trials registered on ClinicalTrials.gov, analyzed funding sources and identified features associated with early discontinuation and results reporting. Methods: We employed a cross-sectional study design with descriptive, logistic regression, cox regression, time series and survival analyses. We downloaded all 270,172 studies registered on the Aggregate Analysis of the ClinicalTrials.gov database from October 1, 2008 to March 9, 2020. After excluding non-interventional trials, applying cancer/oncology specific Medical Subject Heading terms to the remaining trials and excluding phase 1 trials, 27,915 trials were identified for manual review. Primary exposure variables were trial focus: neoplasia site and treatment modality (surgical interventions included investigations of outcomes from surgical resection or intra-operative/peri-operative changes), and funding: industry, U.S. government, academic. Results: 26,815 trials were found to have true oncology content; 1,661 (6.2%) involved surgical oncology, representing 311,789 patients. Funding sources were: 82.7% by academic institutions, 10.9% by industry, and 6.2% by U.S. government. The most studied neoplasia sites were colorectal (17.4% of trials), breast (10.7%), gastric (10.5%), hepatic (8.6%), lung (7.5%), brain/CNS (6.7%) and cervical (6.6%). U.S. government funded surgical oncology trials had the lowest risk of early discontinuation (adjusted HR 0.50, 95% CI: 0.26-0.99, p<0.047) and the highest odds of results reporting (adjusted OR 1.08, 95% CI: 0.55-2.11, p=0.83) (Table 1). Conclusions: There is a paucity of surgical oncology clinical trials compared to other treatment modalities, especially in context of surgery’s role in overall cancer care. From 2008-2020 only 6.2% of trials focused on surgical oncology, and U.S. government funded trials displayed the lowest hazard of early discontinuation and highest odds of results reporting. Stakeholders should look to government funded trials as models of improvement, but must increase representation and results dissemination of surgical oncology trials to guide treatment recommendations. Surgical oncology trial features and associated early discontinuation/results reporting. [Table: see text]

Aspirin and statin drugs have been associated with reduced risk of several gastrointestinal cancers, but their association with gallbladder cancer (GBC) has not been well established. We evaluated the association of aspirin and statins with the risk of GBC. Patients with GBC managed at Mayo Clinic between 2000 and 2019 were matched 1:2 with a general patient pool by age and sex. Univariable and multivariable logistic regression models were used to assess associations between GBC and aspirin or statin use. The analysis included 795 cases and 1590 controls, with a median age of 67 years. Aspirin or statin use alone or in combination was higher in controls (p < 0.001). Univariate analysis showed that the use of aspirin [odds ratio (OR): 0.11; 95%CI: 0.08–0.15] or statins (OR: 0.29; 95%CI: 0.20–0.40) and their combined use (OR: 0.18; 95%CI: 0.13–0.24) was associated with lower risk of GBC. Multivariable analysis revealed that aspirin (OR: 0.12; 95%CI: 0.09–0.16) and combined statins and aspirin (OR: 0.46; 95%CI: 0.31–0.67) were associated with lower risk of GBC. Aspirin alone or in combination with statins is associated with a strongly reduced risk of GBC. Further prospective studies are needed to confirm these results and to elucidate their mechanisms.

Abstract Background: Sorafenib (Sor) remains a first-line option for hepatocellular carcinoma (HCC) or refractory renal cell carcinomas (RCC). PLC/PRF/5 HCC model showed upregulation of hypoxia with enhanced efficacy when Sor is combined with hypoxia-activated prodrug evofosfamide (Evo). Methods: This phase IB 3 + 3 design investigated 3 Evo dose levels (240, 340, 480 mg/m2 on days 8, 15, 22), combined with Sor 200 mg orally twice daily (po bid) on days 1-28 of a 28-day cycle. Primary objectives included determining maximum tolerated dose (MTD) and recommended phase II dose (RP2D) of Sor + Evo. Results: Eighteen patients were enrolled (median age 62.5 years; 17 male /1 female; 12 HCC/6 RCC) across three dose levels (DL0: Sor 200 mg bid/Evo 240 mg/m2 [n=6], DL1:Sor 200 mg bid/Evo 480 mg/m2 [n=5], DL1a: Sor 200 mg bid/Evo 340 mg/m2 [n=7]). Two dose-limiting toxicities (DLTs) were reported with Evo 480 mg/m2 (grade 3 mucositis, grade 4 hepatic failure). Grade 3 rash DLT was observed in one patient at Evo 240 mg/m2. No DLTs were observed at Evo 340 mg/m2. MTD and RP2D were established as Sor 200 mg/Evo 340 mg/m2 and Sor 200/Evo 240 mg/m2, respectively. The most common treatment-related adverse events included fatigue, hand-foot syndrome, hypertension, and nausea/vomiting. Two partial responses were observed, one each at DL0 and DL1a.; disease control rate was 55%.Conclusions: RP2D was established as sorafenib 200 mg bid + Evo 240 mg/m2. While preliminary anti-tumor activity was observed, future development must account for advances in immunotherapy in HCC/RCC. NCT01497444Date of registration December 20, 2011

This series of nine articles (three original articles, six reviews) is presented by international leaders in biliary tract cancers (BTC) [...]

468 Background: The burden of gastrointestinal (GI) disease is high, costing over $97 billion annually in the United States (U.S.) alone. Yet the methodological rigor and characteristics of trials leading to guideline development are rarely explored. In 2007, the U.S. mandated that all interventional studies (Phase II-IV) register with ClinicalTrials.gov, the largest international clinical trial database. We characterized registered GI trials to identify features associated with early discontinuation, results reporting and increased methodological rigor. Methods: We employed a cross-sectional study design with descriptive, logistic regression, cox regression, time series and survival analyses. We downloaded data for 327 075 studies registered on the Aggregate Analysis of the ClinicalTrials.gov database from October 1, 2007 to December 31, 2019. Trials were excluded if registered prior to 2007 (n=38 111) or for non-interventional study design (n=69 233). After applying GI specific Medical Subject Heading terms to the remaining 219 731 trials, 22 339 trials were identified for manual review. 20 548 trials were found to contain true GI content, representing over seven million patients. Primary exposure variables were trial focus (disease process, anatomical location) and funding (industry, U.S. government, academic). Results: Of the 20 548 GI trials, 6.1% were funded by the U.S. government, 35.6% by industry, and 58.3% by academic institutions. The most studied disease process was neoplasia (42.6% of trials), followed by viral hepatitis (10.8%). The majority of neoplasia trials were funded by academic institutions (60.3%) and studied colorectal neoplasms (31.5%), followed by hepatic (17.9%), pancreatic (15.5%), gastric (12.8%), esophageal (10.6%) and biliary tract (4.9%) neoplasms. U.S. government funded trials had the lowest risk of early discontinuation (adjusted Hazard Ratio 0.63, 95% CI: 0.48-0.83, p<0.001) and the highest rates of results reporting (25%, X2 p<0.001). Among all trials, the majority did not report Data Monitoring Committee (DMC) oversight (58.6%). Only 12% of phase III trials employed a rigorous methodology, which we defined as being randomized, double blinded, multi-site, overseen by a DMC, and having enrolled ≥50 patients. Government sponsored trials had the highest proportion of trials meeting this definition (19%). Academic sponsored trials, constituting the majority of trials overall, had the lowest proportion (5.3%), in part due to not meeting the multi-site criteria. Conclusions: Despite constituting the minority of trials overall, U.S. government funded trials displayed the highest methodological rigor. Stakeholders can look to U.S. government funded trials as a model of improvement, but nevertheless must commit to increasing methodological rigor and results dissemination to strengthen trial findings that guide GI clinical recommendations.

Abstract Background: Critically shortened telomeres contribute to chromosomal instability and neoplastic transformation and are associated with early death of patients with certain cancer types. Shorter leukocyte telomere length (LTL) has been associated with higher risk for pancreatic ductal adenocarcinoma (PDAC) and might be associated also with survival of patients with PDAC. We investigated the association between treatment-naïve LTL and overall survival of patients with incident PDAC. Methods: The study included 642 consecutively enrolled PDAC patients in the Mayo Clinic Biospecimen Resource for Pancreas Research. Blood samples were obtained at the time of diagnosis, before the start of cancer treatment, from which LTL was assayed by qRT-PCR. LTL was first modeled as a continuous variable (per-interquartile range decrease in LTL) and then as a categorized variable (short, medium, long). Multivariable-adjusted HRs and 95% confidence intervals (CI) were calculated for overall mortality using Cox proportional hazard models. Results: Shorter treatment-naïve LTL was associated with higher mortality among patients with PDAC (HRcontinuous = 1.13, 95% CI: 1.01–1.28, P = 0.03; HRshortest vs. longest LTL = 1.29, 95% CI: 1.05–1.59, Ptrend = 0.01). There was a difference in the association between LTL and overall mortality by tumor stage at diagnosis; resectable tumors (HRcontinuous = 0.91; 95% CI: 0.73–1.12), locally advanced tumors (HRcontinuous = 1.29; 95% CI: 1.07–1.56), and metastatic tumors (HRcontinuous = 1.17; 95% CI: 0.96–1.42), Pinteraction = 0.04. Conclusion: Shorter treatment-naïve LTL is associated with poorer overall survival of patients with incident PDAC. Impact: Peripheral blood LTL might be a prognostic marker for PDAC.

The current standard treatment for patients with early-stage colon cancer consists of surgical resection, followed by adjuvant therapy in a select group of patients deemed at risk of cancer recurrence. The decision to administer adjuvant therapy, intended to eradicate the clinically inapparent minimal residual disease (MRD) to achieve a cure, is guided by clinicopathologic characteristics of the tumor. However, the risk stratification based on clinicopathologic characteristics is imprecise and results in under or overtreatment in a substantial number of patients. Emerging research indicates that the circulating tumor DNA (ctDNA), a fraction of cell-free DNA (cfDNA) in the bloodstream that originates from the neoplastic cells and carry tumor-specific genomic alterations, is a promising surrogate marker of MRD. Several recent studies suggest that ctDNA-guided risk stratification for adjuvant therapy outperforms existing clinicopathologic prognostic indicators. Preliminary data also indicate that, aside from being a prognostic indicator, ctDNA can inform on the efficacy of adjuvant therapy, which is the underlying scientific rationale for several ongoing clinical trials evaluating ctDNA-guided therapy escalation or de-escalation. Furthermore, serial monitoring of ctDNA after completion of definitive therapy can potentially detect cancer recurrence much earlier than conventional surveillance methods that may provide a critical window of opportunity for additional curative-intent therapeutic interventions. This article presents a critical overview of published studies that evaluated the clinical utility of ctDNA in the management of patients with early-stage colon cancer, and discusses the potential of ctDNA to transform the adjuvant therapy strategies.