PurposeAIO KRK-0104 investigated first-line therapy of metastatic colorectal cancer (mCRC) with cetuximab, capecitabine and irinotecan versus cetuximab, capecitabine and oxaliplatin. This analysis investigated the impact of primary tumor location on outcome of patients.Patients and methodsLeft-sided primary tumors were defined as tumors from rectum to left flexure, while tumors in the remaining colon were regarded right sided. Overall survival (OS), progression-free survival (PFS) and response rate were correlated with primary tumor location. A Cox regression model was used to evaluate interaction between primary tumor location and KRAS mutation.ResultsOf 146 patients of the AIO KRK-0104 trial, 100 patients presented left-sided (of those 68 KRAS codon 12/13 wild-type) and 46 patients right-sided primary tumors (of those 27 KRAS codon 12/13 wild-type). Left-sided tumors were associated with significantly longer OS (p = 0.016, HR = 0.63) and PFS (p = 0.02, HR = 0.67) as compared to right-sided tumors. These effects were present in the KRAS codon 12/13 wild-type population (HR OS: 0.42; HR PFS: 0.54), while no impact of primary tumor location was evident in patients with KRAS codon 12/13 mutant tumors (HR OS: 1.3; HR PFS: 1.01). A significant interaction of KRAS status and primary tumor location concerning OS and PFS was observed.ConclusionOur findings suggest that primary tumor location and KRAS codon 12/13 mutational status interact on the outcome of patients with mCRC receiving cetuximab-based first-line therapy. Left-sided primary tumor location might be a predictor of cetuximab efficacy.

BackgroundAdenocarcinoma originating from the digestive system is a major contributor to cancer-related deaths worldwide. Tumor recurrence, advanced local growth and metastasis are key factors that frequently prevent these tumors from curative surgical treatment. Preclinical research has demonstrated that the dependency of these tumors on supporting mesenchymal stroma results in susceptibility to cell-based therapies targeting this stroma.Methods/DesignTREAT-ME1 is a prospective, uncontrolled, single-arm phase I/II study assessing the safety and efficacy of genetically modified autologous mesenchymal stromal cells (MSC) as delivery vehicles for a cell-based gene therapy for advanced, recurrent or metastatic gastrointestinal or hepatopancreatobiliary adenocarcinoma. Autologous bone marrow will be drawn from each eligible patient after consent for bone marrow donation has been obtained (under a separate EC-approved protocol). In the following ~10 weeks the investigational medicinal product (IMP) is developed for each patient. To this end, the patient’s MSCs are stably transfected with a gamma-retroviral, replication-incompetent and self-inactivating (SIN) vector system containing a therapeutic promoter - gene construct that allows for tumor-specific expression of the therapeutic gene. After release of the IMP the patients are enrolled after given informed consent for participation in the TREAT-ME 1 trial. In the phase I part of the study, the safety of the IMP is tested in six patients by three treatment cycles consisting of re-transfusion of MSCs at different concentrations followed by administration of the prodrug Ganciclovir. In the phase II part of the study, sixteen patients will be enrolled receiving IMP treatment. A subgroup of patients that qualifies for surgery will be treated preoperatively with the IMP to verify homing of the MSCs to tumors as to be confirmed in the surgical specimen.DiscussionThe TREAT-ME1 clinical study involves a highly innovative therapeutic strategy combining cell and gene therapy and is conducted at a high level of pharmaceutical quality ensuring patient safety. This patient-tailored approach represents the first clinical study worldwide utilizing genetically engineered MSCs in humans.Trial registrationEU Clinical Trials Register/European Union Drug Regulating Authorities Clinical Trials Database number: 2012-003741-15

Background: Few studies report the incidence of metastatic patterns in colorectal cancer. Furthermore, little is known about dynamic aspects of these metastases during the course of disease. Methods: This retrospective cohort study involved 385 patients who received anti-tumor treatment at our institution (Department of Medical Oncology, University Hospital Grosshadern, Ludwig-Maximilians-University Munich, Germany) for metastatic colorectal adenocarcinoma between 2007 and 2014. We reviewed all available imaging results of these patients to document the presence and detailed localization of metastases. Results: Most of the evaluated patients were initially diagnosed with metastases in the liver (70%), followed by the lungs (24%), distant lymph nodes (16%), and peritoneum (15%), besides rare anatomical sites (<5%). Colon and rectal cancer as well as synchronous and metachronous metastases differed with regard to the pattern of individual metastatic sites. The median time to first progressive disease (PD) with new metastases was 12.6 months. The time intervals between first and second as well as second and third PD with new metastases were comparable with 10.5 and 10.8 months, respectively. At initial diagnosis, the mean number of metastatic sites was 1.4 and increased to 2.6 at the third PD with new metastases. For patients with initially one metastatic site, the mean number increased to 2.2. Conclusion: The present analysis provides detailed information on the pattern and evolution of colorectal cancer metastases over time. Thus, it may establish the basis for prospective future research in this field.

TREAT‐ME‐1, a Phase 1/2 open‐label multicenter, first‐in‐human, first‐in‐class trial, evaluated the safety, tolerability and efficacy of treatment with genetically modified autologous mesenchymal stromal cells (MSC), MSC_ apceth_101, in combination with ganciclovir in patients with advanced gastrointestinal adenocarcinoma. Immunological and inflammatory markers were also assessed. All patients (3 in Phase 1; 7 in Phase 2) received three treatment cycles of MSC_apceth_101 at one dose level on Day 0, 7, and 14 followed by ganciclovir administration according to the manufacturer's instructions for 48─72 h after MSC_apceth_101 injection. Ten patients were treated with a total dose of 3.0 x 106 cells/kg MSC_apceth_101. 36 adverse events and six serious adverse events were reported. Five patients achieved stable disease (change in target lesions of −2 to +28%). For all patients, the median time to progression was 1.8 months (95% CI: 0.5, 3.9 months). Median overall survival could not be estimated as 8/10 patients were still alive at the end of the study (1 year) and therefore censored. Post‐study observation of patients showed a median overall survival of 15.6 months (ranging from 2.2─27.0 months). Treatment with MSC_apceth_101 and ganciclovir did not induce a consistent increase or decrease in levels of any of the tumor markers analyzed. No clear trends in the immunological markers assessed were observed. MSC_apceth_101 in combination with ganciclovir was safe and tolerable in patients with advanced gastrointestinal adenocarcinoma, with preliminary signs of efficacy in terms of clinical stabilization of disease.

The aim of this study was to investigate the impact of midgut versus hindgut as the primary tumor site in patients with metastatic colorectal cancer (mCRC) receiving chemotherapy with FuFIRI or mIROX. We analyzed 423 patients from a phase III trial that randomized patients in a 1 : 1 fashion to either FuFIRI or mIROX. The cohort was grouped into midgut (n=82) and hindgut (n=341) primary tumors. The primary tumor site (midgut vs. hindgut) was correlated with parameters of treatment efficacy and survival. Our cohort comprised 82 patients presenting with primary midgut tumors and 341 with primary hindgut tumors. Tumors of midgut origin compared with hindgut origin were associated with inferior outcome. Objective response rate was 37 versus 43% (P=0.34), median progression-free survival was 6.0 versus 8.2 months (P=0.024, hazard ratio: 0.75), and median overall survival was 13.6 versus 21.8 months (P=0.001, hazard ratio: 0.65). Patients with midgut mCRC showed a clear trend toward inferior outcome in both study arms. However, the effect appeared less pronounced in the mIROX arm. Further datasets from large trials with various regimens are required as confirmation.