ß-glucan: a potent adjuvant in immunotherapy for digestive tract tumors.

The immunotherapy for gastrointestinal tumors, as a significant research direction in the field of oncology treatment in recent years, has garnered extensive attention due to its potential therapeutic efficacy and promising clinical application prospects. Recent advances in immunotherapy notwithstanding, challenges persist, such as side effects, the complexity of the tumor immune microenvironment, variable patient responses, and drug resistance. Consequently, there is a pressing need to explore novel adjunctive therapeutic modalities. ß-glucan, an immunomodulatory agent, has exhibited promising anti-tumor efficacy in preclinical studies involving colorectal cancer, pancreatic cancer, and gastric cancer, while also mitigating the adverse reactions associated with chemotherapy and enhancing patients' quality of life. However, further clinical and fundamental research is warranted to comprehensively evaluate its therapeutic potential and underlying biological mechanisms. In the future, ß-glucan holds promise as an adjunctive treatment for gastrointestinal tumors, potentially bringing significant benefits to patients.

Efficacy of Trametinib in Neurofibromatosis Type 1-Associated Gastrointestinal Stromal Tumors: A Case Report.

Trametinib, an MEK inhibitor, may offer a new therapeutic option for patients with NF1-related GIST.

Targeting the Wnt/ß-catenin signal pathway for the treatment of gastrointestinal cancer: Potential for advancement.

Gastrointestinal cancers (GICs) are highly prevalent cancers that threaten human health worldwide. The Wnt/ß-catenin signaling pathway has been reported to play a pivotal role in the carcinogenesis of GICs. Numerous interventions targeting the Wnt/ß-catenin signaling in GICs are currently being tested in clinical trials with promising results. Unfortunately, there are no clinically approved drugs that effectively target this pathway. This comprehensive review aims to evaluate the impact of clinical therapies targeting the Wnt/ß-catenin signaling pathway in GICs. By integrating data from bioinformatics databases and recent literature from the past five years, we examine the heterogeneous expression and regulatory mechanisms of Wnt/ß-catenin pathway genes and proteins in GICs. Specifically, we focus on expression patterns, mutation frequencies, and clinical prognoses to understand their implications for treatment strategies. Additionally, we discuss recent clinical trial efforts targeting this pathway. Understanding the inhibitors currently under clinical investigation may help optimize foundational research and clinical strategies. We hope that elucidating the current status of precision therapeutic stratification for patients targeting the Wnt/ß-catenin pathway will guide future innovations in precision medicine for GICs.

A multicenter, prospective, non-interventional real-world study to assess the effectiveness of mecapegfilgrastim in preventing neutropenia in patients with gastrointestinal cancer.

BACKGROUND: Mecapegfilgrastim, a long-acting granulocyte-colony stimulating factor has been approved for reducing the incidence of infection, particularly febrile neutropenia (FN), in China. OBJECTIVE: We conducted a multicenter prospective observational study to examine the safety and effectiveness of mecapegfilgrastim in preventing neutropenia in gastrointestinal patients receiving the chemotherapy, including S-1/capecitabine-based regimens or the fluorouracil, leucovorin, oxaliplatin, and irinotecan (FOLFOXIRI)/fluorouracil, leucovorin, and oxaliplatin (FOLFOX)/fluorouracil, leucovorin, oxaliplatin, and irinotecan (FOLFIRINOX) regimens. METHOD: Five hundred and sixty-one gastrointestinal patients from 40 sites across China, between May 2019 and November 2021, were included. The administration of mecapegfilgrastim was prescribed at the discretion of local physicians. RESULTS: The most common adverse drug reactions (ADRs) of any grade for all patients was increased white blood cells (2.9%). Grade 3/4 ADRs were observed for anemia (0.2%), decreased white blood cells (0.2%), and decreased neutrophil count (0.2%). Among the 116 patients who received S-1/capecitabine-based chemotherapy throughout all cycles, ADRs of any grade included anemia (1.7%), myalgia (0.9%), and increased alanine aminotransferase (0.9%). No grade 3/4 ADRs were observed. In 414 cycles of patients who underwent S-1/capecitabine-based regimens, only one (0.2%) cycle experienced grade 4 neutropenia. In the FOLFIRINOX, FOLFOXIRI, and FOLFOX chemotherapy regimens, grade 4 neutropenia occurred in one (2.7%) of 37 cycles, four (4.7%) of 85 cycles, and two (1.2%) of 167 cycles, respectively. CONCLUSION: In a real-world setting, mecapegfilgrastim has proven effective in preventing severe neutropenia in gastrointestinal patients following chemotherapy. This includes commonly used moderate or high-risk FN regimens or regimens containing S1/capecitabine, all of which have demonstrated favorable efficacy and safety profiles.

Real-world data of anamorelin in advanced gastrointestinal cancer patients with cancer cachexia.

BACKGROUND: Cancer cachexia is characterized by the loss of body weight (BW) and anorexia. Anamorelin (ANAM) is a selective ghrelin receptor agonist with appetite-enhancing anabolic action. The ONO-7643-05 trial demonstrated that ANAM increased lean body mass and improved anorexia in a Japanese population. However, the clinical outcomes of patients on ANAM have not yet been reported. PATIENTS AND METHODS: We investigated the clinical outcomes of patients with unresectable, advanced, or recurrent gastrointestinal cancer (colorectal, gastric, or pancreatic cancer) who were treated with ANAM between April 2017 and August 2022. Cachexia was defined as the presence of anorexia and a loss of ≥ 5% of BW within 6 months. To evaluate the response to ANAM, the patients who had discontinued ANAM within 3 weeks were excluded. Response to ANAM was defined as maintenance of or increase in BW and improved appetite from baseline at every 3-week evaluation. We also collected data on the reasons for the discontinuation of ANAM and the correlation between clinical factors and ANAM response. Safety analysis of ANAM was performed for all patients who received ANAM. RESULTS: Seventy-four patients were included in this study (49 males and 25 females), with a median age of 67.1 years (range, 36-83). The primary tumors were colorectal cancer in 27 (36.5%), gastric cancer in 20 (27.0%), and pancreatic cancer in 27 (36.5%). The Eastern Cooperative Oncology Group performance status was 0 in 10 (13.5%), 1 in 44 (59.5%), and ≥ 2 in 20 (27.0%). The number of previous chemotherapy regimens was 0 in 20 (27.0%), 1 in 22 (29.7%), and ≥ 2 in 32 (43.2%). ANAM was discontinued within 3 weeks in 28 patients for the following reasons: low-grade (grade 1 or 2) adverse events in 15 patients, ileus in three, grade 3 fatigue in one, progressive disease in one, censored follow-up in six, and unknown reasons in three. The proportion of ANAM responders was 63.6% (95% confidence interval, 47.8-77.6%). Among baseline characteristics, age ≥ 75 attenuated the ANAM response (p = 0.03). ANAM responders showed better disease control with chemotherapy than non-responders (75.0% vs. 37.5%, p = 0.02). CONCLUSIONS: ANAM may improve the outcomes of patients with gastrointestinal cancer cachexia in clinical practice.

MIR27A Gene Polymorphism Modifies the Effect of Common DPYD Gene Variants on Severe Toxicity in Patients with Gastrointestinal Tumors Treated with Fluoropyrimidine-Based Anticancer Therapy.

To reduce severe fluoropyrimidine-related toxicity, pharmacogenetic guidelines recommend a dose reduction for carriers of four high-risk variants in the DPYD gene (*2A, *13, c.2846A>T, HapB3). The polymorphism in the MIR27A gene has been shown to enhance the predictive value of these variants. Our study aimed to explore whether rs895819 in the MIR27A gene modifies the effect of five common DPYD variants: c.1129-5923C>G (rs75017182, HapB3), c.2194G>A (rs1801160, *6), c.1601G>A (rs1801158, *4), c.496A>G (rs2297595), and c.85T>C (rs1801265, *9A). The study included 370 Caucasian patients with gastrointestinal tumors who received fluoropyrimidine-containing chemotherapy. Genotyping was performed using high-resolution melting analysis. The DPYD*6 allele was associated with overall severe toxicity and neutropenia with an increased risk particularly pronounced in patients carrying the MIR27A variant. All carriers of DPYD*6 exhibited an association with asthenia regardless of their MIR27A status. The increased risk of neutropenia in patients with c.496G was only evident in those co-carrying the MIR27A variant. DPYD*4 was also significantly linked to neutropenia risk in co-carriers of the MIR27A variant. Thus, we have demonstrated the predictive value of the *6, *4, and c.496G alleles of the DPYD gene, considering the modifying effect of the MIR27A polymorphism.

A novel artificial intelligence network to assess the prognosis of gastrointestinal cancer to immunotherapy based on genetic mutation features.

Background: Immune checkpoint inhibitors (ICIs) have revolutionized gastrointestinal cancer treatment, yet the absence of reliable biomarkers hampers precise patient response prediction. Methods: We developed and validated a genomic mutation signature (GMS) employing a novel artificial intelligence network to forecast the prognosis of gastrointestinal cancer patients undergoing ICIs therapy. Subsequently, we explored the underlying immune landscapes across different subtypes using multiomics data. Finally, UMI-77 was pinpointed through the analysis of drug sensitization data from the Genomics of Drug Sensitivity in Cancer (GDSC) database. The sensitivity of UMI-77 to the AGS and MKN45 cell lines was evaluated using the cell counting kit-8 (CCK8) assay and the plate clone formation assay. Results: Using the artificial intelligence network, we developed the GMS that independently predicts the prognosis of gastrointestinal cancer patients. The GMS demonstrated consistent performance across three public cohorts and exhibited high sensitivity and specificity for 6, 12, and 24-month overall survival (OS) in receiver operating characteristic (ROC) curve analysis. It outperformed conventional clinical and molecular features. Low-risk samples showed a higher presence of cytolytic immune cells and enhanced immunogenic potential compared to high-risk samples. Additionally, we identified the small molecule compound UMI-77. The half-maximal inhibitory concentration (IC50) of UMI-77 was inversely related to the GMS. Notably, the AGS cell line, classified as high-risk, displayed greater sensitivity to UMI-77, whereas the MKN45 cell line, classified as low-risk, showed less sensitivity. Conclusion: The GMS developed here can reliably predict survival benefit for gastrointestinal cancer patients on ICIs therapy.

Incorporating Tumor Genomic Profiling and Circulating Tumor Cell-derived Organoids into Clinical Practice for Gastrointestinal Cancers.

BACKGROUND/AIM: Precision medicine aims to revolutionize healthcare by tailoring treatment regimens. This study aimed to integrate comprehensive tumor genomic profiling (CTGP) by targeted-gene panel sequencing and drug screening by circulating tumor cell-derived organoids (CTOs) into clinical practice for the treatment of gastrointestinal (GI) cancers. PATIENTS AND METHODS: Nine patients with various GI cancers underwent CTGP and CTO drug sensitivity testing. CTGP results guided targeted therapy and immunotherapy, while CTO drug sensitivity predicted response to chemotherapy and targeted agents. The drug recommendations from two platforms were correlated with the treatment response to the suggested medications retrospectively. RESULTS: Five patients received therapies aligned with CTGP, including HER2-targeted treatment, immunotherapy, and BRAF/MEK dual inhibition, showing positive responses. CTO drug sensitivity predicted progression under regorafenib (low potential benefit) and good response to chemotherapy with high potential benefit. The combination of CTGP and CTO drug sensitivity may exhibit significant correlation with clinical outcomes during treatment with candidate drugs, demonstrating a sensitivity of 79% and an accuracy of 75%. This encompasses various treatment modalities, such as chemotherapy, targeted therapy, and immunotherapy. CONCLUSION: The present investigation elucidated the integration of CTGP and CTO drug sensitivity screening into clinical practice in a complementary manner, showcasing a significant correlation between treatment response and testing outcomes. Additional prospective evaluation of these two testing modalities in a large cohort is warranted to confirm whether the inclusion of CTO drug sensitivity screening confers enhanced survival benefits compared to utilizing CTGP alone.

Icariside I enhances the effects of immunotherapy in gastrointestinal cancer via targeting TRPV4 and upregulating the cGAS-STING-IFN-I pathway.

Gastrointestinal cancer is among the most common cancers worldwide. Immune checkpoint inhibitor-based cancer immunotherapy has become an innovative approach in cancer treatment; however, its efficacy in gastrointestinal cancer is limited by the absence of infiltration of immune cells within the tumor microenvironment. Therefore, it is therefore urgent to develop a novel therapeutic drug to enhance immunotherapy. In this study, we describe a previously unreported potentiating effect of Icariside I (ICA I, GH01), the main bioactive compound isolated from the Epimedium species, on anti-tumor immune responses. Mechanistically, molecular docking and SPR assay result show that ICA I binding with TRPV4. ICA I induced intracellular Ca2+ increasing and mitochondrial DNA release by targeting TRPV4, which triggered cytosolic ox-mitoDNA release. Importantly, these intracellular ox-mitoDNA fragments were taken up by immune cells in the tumor microenvironment, which amplified the immune response. Moreover, our study shows the remarkable efficacy of sequential administration of ICA I and anti-α-PD-1 mAb in advanced tumors and provides a strong scientific rationale for recommending such a combination therapy for clinical trials. ICA I enhanced the anti-tumor effects with PD-1 inhibitors by regulating the TRPV4/Ca2+/Ox-mitoDNA/cGAS/STING axis. We expect that these findings will be translated into clinical therapies, which will benefit more patients with cancer in the near future.

Garcinol in gastrointestinal cancer prevention: recent advances and future prospects.

Gastrointestinal cancers continue to pose a significant global health challenge, with millions of new cases diagnosed each year. Despite advancements in treatment, the prognosis for many patients remains poor. This article explores the potential of garcinol, a polyisoprenylated benzophenone found in various Garcinia species, as a therapeutic agent against gastrointestinal malignancies. The objective is to review recent research on garcinol's anticancer properties, its mechanisms of action, and safety aspects. Garcinol exhibits anticancer effects in esophageal, gastric, colorectal, pancreatic, and liver cancers by inhibiting metastasis, inducing apoptosis, and targeting key molecular pathways in cancer progression. Nanotechnology is explored as a means to enhance garcinol delivery and efficacy. Safety assessments suggest a promising toxicity profile. Garcinol shows significant potential as a natural therapeutic agent for gastrointestinal cancers, and future research is needed on optimizing its delivery, exploring synergistic combinations, and conducting clinical trials to validate its efficacy and safety for clinical applications.

Interpretable artificial intelligence to optimise use of imatinib after resection in patients with localised gastrointestinal stromal tumours: an observational cohort study.

BACKGROUND: Current guidelines recommend use of adjuvant imatinib therapy for many patients with gastrointestinal stromal tumours (GISTs); however, its optimal treatment duration is unknown and some patient groups do not benefit from the therapy. We aimed to apply state-of-the-art, interpretable artificial intelligence (ie, predictions or prescription logic that can be easily understood) methods on real-world data to establish which groups of patients with GISTs should receive adjuvant imatinib, its optimal treatment duration, and the benefits conferred by this therapy. METHODS: In this observational cohort study, we considered for inclusion all patients who underwent resection of primary, non-metastatic GISTs at the Memorial Sloan Kettering Cancer Center (MSKCC; New York, NY, USA) between Oct 1, 1982, and Dec 31, 2017, and who were classified as intermediate or high risk according to the Armed Forces Institute of Pathology Miettinen criteria and had complete follow-up data with no missing entries. A counterfactual random forest model, which used predictors of recurrence (mitotic count, tumour size, and tumour site) and imatinib duration to infer the probability of recurrence at 7 years for a given patient under each duration of imatinib treatment, was trained in the MSKCC cohort. Optimal policy trees (OPTs), a state-of-the-art interpretable AI-based method, were used to read the counterfactual random forest model by training a decision tree with the counterfactual predictions. The OPT recommendations were externally validated in two cohorts of patients from Poland (the Polish Clinical GIST Registry), who underwent GIST resection between Dec 1, 1981, and Dec 31, 2011, and from Spain (the Spanish Group for Research in Sarcomas), who underwent resection between Oct 1, 1987, and Jan 30, 2011. FINDINGS: Among 1007 patients who underwent GIST surgery in MSKCC, 117 were included in the internal cohort; for the external cohorts, the Polish cohort comprised 363 patients and the Spanish cohort comprised 239 patients. The OPT did not recommend imatinib for patients with GISTs of gastric origin measuring less than 15·9 cm with a mitotic count of less than 11·5 mitoses per 5 mm2 or for those with small GISTs (<5·4 cm) of any site with a count of less than 11·5 mitoses per 5 mm2. In this cohort, the OPT cutoffs had a sensitivity of 92·7% (95% CI 82·4-98·0) and a specificity of 33·9% (22·3-47·0). The application of these cutoffs in the two external cohorts would have spared 38 (29%) of 131 patients in the Spanish cohort and 44 (35%) of 126 patients in the Polish cohort from unnecessary treatment with imatinib. Meanwhile, the risk of undertreating patients in these cohorts was minimal (sensitivity 95·4% [95% CI 89·5-98·5] in the Spanish cohort and 92·4% [88·3-95·4] in the Polish cohort). The OPT tested 33 different durations of imatinib treatment (<5 years) and found that 5 years of treatment conferred the most benefit. INTERPRETATION: If the identified patient subgroups were applied in clinical practice, as many as a third of the current cohort of candidates who do not benefit from adjuvant imatinib would be encouraged to not receive imatinib, subsequently avoiding unnecessary toxicity on patients and financial strain on health-care systems. Our finding that 5 years is the optimal duration of imatinib treatment could be the best source of evidence to inform clinical practice until 2028, when a randomised controlled trial with the same aims is expected to report its findings. FUNDING: National Cancer Institute.

Regorafenib synergizes with TAS102 against multiple gastrointestinal cancers and overcomes cancer stemness, trifluridine-induced angiogenesis, ERK1/2 and STAT3 signaling regardless of KRAS or BRAF mutational status.

Single-agent TAS102 (trifluridine/tipiracil) and regorafenib are FDA-approved treatments for metastatic colorectal cancer (mCRC). We previously reported that regorafenib combined with a fluoropyrimidine can delay disease progression in clinical case reports of multidrug-resistant mCRC patients. We hypothesized that the combination of TAS102 and regorafenib may be active in CRC and other gastrointestinal (GI) cancers and may in the future provide a treatment option for patients with advanced GI cancer. We investigated the therapeutic effect of TAS102 in combination with regorafenib in preclinical studies employing cell culture, colonosphere assays that enrich for cancer stem cells, and in vivo. TAS102 in combination with regorafenib has synergistic activity against multiple GI cancers in vitro including colorectal and gastric cancer, but not liver cancer cells. TAS102 inhibits colonosphere formation and this effect is potentiated by regorafenib. In vivo anti-tumor effects of TAS102 plus regorafenib appear to be due to anti-proliferative effects, necrosis and angiogenesis inhibition. Growth inhibition by TAS102 plus regorafenib occurs in xenografted tumors regardless of p53, KRAS or BRAF mutations, although more potent tumor suppression was observed with wild-type p53. Regorafenib significantly inhibits TAS102-induced angiogenesis and microvessel density in xenografted tumors, as well inhibits TAS102-induced ERK1/2 activation regardless of RAS or BRAF status in vivo. TAS102 plus regorafenib is a synergistic drug combination in preclinical models of GI cancer, with regorafenib suppressing TAS102-induced increase in microvessel density and p-ERK as contributing mechanisms. The TAS102 plus regorafenib drug combination may be further tested in gastric and other GI cancers.

Survival of advanced/recurrent gastrointestinal stromal tumors treated with tyrosine kinase inhibitors in Taiwan: a nationwide registry study.

BACKGROUND: Most gastrointestinal stromal tumors (GISTs) harbor c-KIT or PDGFRA mutations. Administration of tyrosine kinase inhibitors (TKIs) has significantly improved the survival of patients with GISTs. We aimed to evaluate the clinical outcome of advanced or recurrent GIST patients in Taiwan. METHODS: Patients diagnosed between 2010 and 2020 were enrolled. The collected data included baseline characteristics, treatment pattern, treatment outcome, genetic aberrations and survival status. Progression-free survival (PFS) and overall survival (OS) were analyzed and plotted with the Kaplan-Meier method. Cox regression analysis was used to analyze the prognostic factors of survival. RESULTS: A total of 224 patients with advanced or recurrent GISTs treated with TKIs were enrolled. All patients received imatinib treatment. Ninety-three and 42 patients received sunitinib and regorafenib treatment, respectively. The 48-month PFS and OS rates for patients treated with imatinib were 50.5% and 79.5%, respectively. c-KIT exon 9 and PDGFRA mutations were prognostic factors for a poor PFS and PDGFRA mutation was a prognostic factor for a poor OS in patients treated with imatinib in multivariate Cox regression analysis. The median PFS of patients who received sunitinib treatment was 12.76 months (95% confidence interval (CI), 11.01-14.52). Patients with c-KIT exon 9 mutations had a longer PFS than those with other genetic aberrations. The median PFS of patients treated with regorafenib was 7.14 months (95% CI, 3.39-10.89). CONCLUSIONS: We present real-world clinical outcomes for advanced GIST patients treated with TKIs and identify mutational status as an independent prognostic factor for patient survival.

The Discovery of GIT1/ß-Pix Inhibitors: Virtual Screening and Biological Evaluation of New Small-molecule Compounds with Anti-invasion Effect in Gastrointestinal Neoplasms.

Background and Objective: GIT1 (G-protein-coupled receptor kinase interacting protein-1) has been found to be highly related with cancer cell invasion and metastasis in many cancer types. ß-Pix (p21-activated kinase-interacting exchange factor) is one of the proteins that interact with GIT1. Targeting GIT1/ß-Pix complex might be a potential therapeutic strategy for interfering cancer metastasis. However, at present, no well-recognized small-molecule inhibitor targeting GIT1/ß-Pix is available. Thus, we aim to discover novel GIT1/ß-Pix inhibitors with simple scaffold, high activity and low toxicity to develop new therapeutic strategies to restrain cancer metastasis. Methods: GIT1/ß-Pix inhibitors were identified from ChemBridge by virtual screening. Briefly, the modeling of GIT1 was performed and the establishment of GIT1/ß-Pix binding pocket enabled the virtual screening to identify the inhibitor. In addition, direct binding of the candidate molecules to GIT1 was detected by biolayer interferometry (BLI) to discover the hit compound. Furthermore, the inhibitory effect on invasion of stomach and colon cancer cells in vitro was carried out by the transwell assay and detection of epithelial-mesenchymal transition (EMT)-related proteins. Finally, the binding mode of hit compound to GIT1 was estimated by molecular dynamics simulation to analyze the key amino residues to guide further optimization. Results: We selected the top 50 compounds from the ChemBridge library by virtual screening. Then, by skeleton similarity analysis nine compounds were selected for further study. Furthermore, the direct interaction of nine compounds to GIT1 was detected by BLI to obtain the best affinitive compound. Finally, 17302836 was successfully identified (KD = 84.1±2.0 µM). In vitro tests on 17302836 showed significant anti-invasion effect on gastric cancer and colorectal cancer. Conclusion: We discovered a new GIT1/ß-Pix inhibitor (17302836) against gastrointestinal cancer invasion and metastasis. This study provides a promising candidate for developing new GIT1/ß-Pix inhibitors for tumor treatment.

HER-2 directed therapies across gastrointestinal tract cancers - A new frontier.

Gastrointestinal (GI) cancers are common and in the metastatic setting they have a poor prognosis. The current mainstay of treatment of GI cancers is chemotherapy; however, the biomarker-directed treatment landscape is evolving. HER-2 is overexpressed in a portion of GI cancers and is an emerging target for therapy, with recent FDA tumor agnostic approval for trastuzumab deruxtecan. Testing for HER-2 expression is not standardized across GI cancers, methodology requires further optimization and standardization as HER-2 targeted therapy emerges into the treatment landscape. There is established rationale for use of HER-2 targeted therapy in first line treatment of metastatic gastric cancer, and emerging evidence with variable benefit in bile duct, pancreatic and colorectal cancers.

Home-based aerobic exercise feasibility in oxaliplatin-receiving newly-diagnosed cancer survivors.

PURPOSE: Physical activity (PA) is beneficial but difficult to maintain during chemotherapy. This pilot RCT explored the feasibility of the MI-Walk intervention-an 8-week motivational enhancement therapy- and home-based brisk walking intervention-among gastrointestinal (GI) cancer survivors receiving chemotherapy. METHODS: Sixty stage II-IV GI cancer survivors were recruited from 5 sites at their second infusion visit. Participants were randomized to receive PA education alone or the MI-Walk intervention: motivational enhancement therapy consisting of 3 motivational interviewing and self-efficacy-enhancing counseling sessions, a Fitbit Charge 2, exercise diaries, telephone follow-up, scripted motivational email messages, and optional weekly walking groups. RESULTS: The enrollment and completion rates were 62% and 90%, respectively. The MI-Walk participants (n = 29; mean age = 56.79, SD = 11.72; 97% white; 79% male) reported a baseline moderate-vigorous PA duration of 250.93 (SD = 636.52) min/wk. The mean MI-Walk Intervention acceptability score was 50.32 (SD = 12.02) on a scale of 14-70. Mean Fitbit and counseling helpfulness scores on a 5-point scale were 3.67 (SD = 1.43) and 3.44 (SD = 1.36), respectively. Participants' Fitbit moderate-vigorous PA 8-week averages ranged from 0 to 716.88 min/wk; 64% of participants adhered to ≥127 min/wk. Several characteristics (e.g., age, comorbidity, PA level, employment status, BMI, education level, gender, symptoms) were associated with enrollment, attrition, and intervention acceptability and adherence (p < 0.05). CONCLUSION: Enrollment and retention were adequate. The Fitbit and counseling were the most helpful. Acceptability and adherence varied based on participant characteristics; therefore, intervention tailoring and further research among cancer survivors less physically active at baseline and most in need of complex exercise intervention are needed. CLINICALTRIALS: gov NCT03515356.

How to Balance Prognostic Factors in Controlled Phase II Trials: Stratified Permuted Block Randomization or Minimization? An Analysis of Clinical Trials in Digestive Oncology.

In controlled phase II trials, major prognostic factors need to be well balanced between arms. The main procedures used are SPBR (Stratified Permuted Block Randomization) and minimization. First, we provide a systematic review of the treatment allocation procedure used in gastrointestinal oncology controlled phase II trials published in 2019. Second, we performed simulations using data from six phase II studies to measure the impacts of imbalances and bias on the efficacy estimations. From the 40 articles analyzed, all mentioned randomization in both the title and abstract, the median number of patients included was 109, and 77.5% were multicenter. Of the 27 studies that reported at least one stratification variable, 10 included the center as a stratification variable, 10 used minimization, 9 used SBR, and 8 were unspecified. In real data studies, the imbalance increased with the number of centers. The total and marginal imbalances were higher with SBR than with minimization, and the difference increased with the number of centers. The efficiency estimates per arm were close to the original trial estimate in both procedures. Minimization is often used in cases of numerous centers and guarantees better similarity between arms for stratification variables for total and marginal imbalances in phase II trials.

Adjuvant imatinib in high-risk resected gastrointestinal stromal tumors: Merely delaying the inevitable?

INTRODUCTION: Patients with high-risk resected gastrointestinal stromal tumors (GIST) receiving adjuvant imatinib have improved recurrence-free survival (RFS), however whether a complete cytocidal effect exists is unknown. We investigated this using a normalized recurrence timeline measured from end of oncologic treatment (EOOT), defined as the later of resection or end of adjuvant therapy. METHODS: We reviewed patients with resected high-risk GIST at our cancer center from 2003 to 2018. RFS (measured from resection and EOOT), overall survival (OS), and time to imatinib resistance (TTIR) were analyzed using Kaplan-Meier analysis and multivariable Cox proportional hazards modeling. The performance of the Memorial Sloan Kettering (MSK) GIST nomogram was assessed. RESULTS: We identified 86 patients with high-risk GIST with a median 106 months of postsurgical follow-up. One-third (n = 29; 34%) did not receive adjuvant imatinib, while 57 (66%) did for a median of 3 years. The MSK nomogram-predicted 5-year RFS for patients receiving adjuvant imatinib was similar to those who did not (29% vs. 31%, p = 0.64). When RFS was measured from EOOT, the MSK-predicted RFS was independently associated with EOOT RFS (hazard ratio 0.22, p = 0.02), while adjuvant imatinib receipt and duration were not. Neither receipt nor duration of adjuvant imatinib were associated with TTIR or OS (all p > 0.05). CONCLUSIONS: Treatment with adjuvant imatinib delays, but does not clearly impact ultimate recurrence, TTIR, or OS, suggesting many patients with high-risk GIST may receive adjuvant imatinib unnecessarily. Additional studies are needed to establish the benefit of adjuvant therapy versus initiating therapy at first radiographic recurrence.