Chemotherapy for colorectal cancer liver metastases

Antitumor Mechanism and Therapeutic Potential of Cordycepin Derivatives

Cordycepin has good antitumor activity, but its clinical application is limited due to the easy deamination of N6 in structure. In this study, a large lipolysis group was introduced at the cordycepin N6 to improve the problem, cordycepin derivatives (3a-4c) were synthesized, and biological evaluation of compounds was studied. In this study, the vitro antitumor activity of the compounds against MCF7 cells, HepG2 cells and SGC-7901 cells was evaluated by MTT assay. In the results, compound 4a showed the most obvious inhibitory effect on MCF7 cells with an IC50 value of 27.57 ± 0.52 μM, which was much lower than cordycepin. Compound 4a showed high selectivity between MCF7 and normal MCF-10A cells. Further biological evaluation showed that compound 4a promoted apoptosis and blocked the cell cycle in the G0/G1 phase. Then, Western Blot was used to detect related apoptotic proteins. It was found that Compound 4a could down-regulate the expression of Bcl-2 protein and up-regulate the expression of p53, Bax, Caspase-3 and Caspase-9 proteins. The mitochondrial membrane potential decreased continuously and the positive expression rate decreased. It was speculated that compound 4a induced the apoptosis of MCF7 cells through the mitochondrial pathway.

Liver metastases: The role of magnetic resonance imaging

The liver is one of the organs most commonly involved in metastatic disease, especially due to its unique vascularization. It's well known that liver metastases represent the most common hepatic malignant tumors. From a practical point of view, it's of utmost importance to evaluate the presence of liver metastases when staging oncologic patients, to select the best treatment possible, and finally to predict the overall prognosis. In the past few years, imaging techniques have gained a central role in identifying liver metastases, thanks to ultrasonography, contrast-enhanced computed tomography (CT), and magnetic resonance imaging (MRI). All these techniques, especially CT and MRI, can be considered the non-invasive reference standard techniques for the assessment of liver involvement by metastases. On the other hand, the liver can be affected by different focal lesions, sometimes benign, and sometimes malignant. On these bases, radiologists should face the differential diagnosis between benign and secondary lesions to correctly allocate patients to the best management. Considering the above-mentioned principles, it's extremely important to underline and refresh the broad spectrum of liver metastases features that can occur in everyday clinical practice. This review aims to summarize the most common imaging features of liver metastases, with a special focus on typical and atypical appearance, by using MRI.

A mini-review: Advances in plant-derived extracellular vesicles as nano-delivery systems for tumour therapy

Extracellular vesicles are functionally active, nanoscale, membrane-bound vesicles that can be secreted by all cells. They have a key role in most health and disease states and have gradually become a promising class of delivery vehicles for targeted therapies for a variety of diseases. Plant-derived extracellular vesicles have received increasing attention based on their easy availability, non-toxicity and high absorption. However, compared with mammalian extracellular vesicles, the role of these nanoparticles as nano-delivery systems in tumour therapy has been underestimated. In this paper, the application of plant-derived extracellular vesicles and their nano-derivatives as nano-delivery systems in tumour therapy is reviewed to illustrate their great application potential.

Comparison between fluoropyrimidine-hepatic arterial infusion and systemic chemotherapy for unresectable liver metastases: A protocol for systematic review and meta-analysis based on 16 observational studies

BACKGROUND

The benefit of loco-regional treatments such as hepatic arterial infusion (HAI) in terms of survival and response rate is unclear. The aim of this work is to quantitatively summarize the results of both randomized controlled trials (RCTs) and non-randomized studies of interventions (NRSIs) comparing fluoropyrimidine-HAI (F-HAI) to systemic chemotherapy (SCT) for the treatment of colorectal liver metastases (CRLMs).

METHODS

We searched the Cochrane Library, PubMed, EMBASE, and Web of Science up to July 1, 2021. The outcome measures were tumor response rate and overall survival (OS). Both RCTs and NRSIs comparing HAI to SCT for patients with unresectable CRLMs were included. The outcome measures were tumor response rate and OS. Two reviewers assessed trial quality and extracted data independently. All statistical analyses were performed using standard statistical procedures provided in Review Manager 5.2.

RESULTS

A total of 16 studies including 11 RCTs and 5 NRSIs were identified for the present meta-analysis. Nine RCTs compared F-HAI to SCT for patients with unresectable CRLMs and the pooled result indicated that patients who received F-HAI experienced more than twofold response rate than SCT, with a pooled risk ratio of 2.10 (95%CI 1.59-2.79; P < .00001). In addition, the pooled result based on RCTs showed that F-HAI had a significant benefit regarding OS, with a pooled HR of 0.83 (95% CI 0.70-0.99; P = .04). Similarly, the benefit of F-HAI in terms of OS was also observed in the results of NRSIs.

CONCLUSIONS

Our results indicated that the F-HAI regimen had a greater tumor response rate and survival advantage than SCT for patients with unresectable CRLMs. Future propensity score-matched analyses with a large sample size should be conducted to support the evidence of our results based on RCTs and NRSIs.

Liver Immune Microenvironment and Metastasis from Colorectal Cancer-Pathogenesis and Therapeutic Perspectives

A drastic difference exists between the 5-year survival rates of colorectal cancer patients with localized cancer and distal organ metastasis. The liver is the most favorable organ for cancer metastases from the colorectum. Beyond the liver-colon anatomic relationship, emerging evidence highlights the impact of liver immune microenvironment on colorectal liver metastasis. Prior to cancer cell dissemination, hepatocytes secrete multiple factors to recruit or activate immune cells and stromal cells in the liver to form a favorable premetastatic niche. The liver-resident cells including Kupffer cells, hepatic stellate cells, and liver-sinusoidal endothelial cells are co-opted by the recruited cells, such as myeloid-derived suppressor cells and tumor-associated macrophages, to establish an immunosuppressive liver microenvironment suitable for tumor cell colonization and outgrowth. Current treatments including radical surgery, systemic therapy, and localized therapy have only achieved good clinical outcomes in a minority of colorectal cancer patients with liver metastasis, which is further hampered by high recurrence rate. Better understanding of the mechanisms governing the metastasis-prone liver immune microenvironment should open new immuno-oncology avenues for liver metastasis intervention.

Cyanidin-3-O-glucoside and cisplatin inhibit proliferation and downregulate the PI3K/AKT/mTOR pathway in cervical cancer cells

Natural compounds have been increasingly investigated as substances enhancing the effect of drugs and reducing drug-related adverse reactions. The objective of this study was to determine how a combination of cisplatin (DDP) with cyanidin-3-O-glucoside (C3G) affected malignancy features of cervical cancer cells. The results demonstrated that the proliferation of HeLa cells treated with 5 µg/ml DDP, 400 µg/ml C3G, or a combination of both (5 µg/ml DDP and 400 µg/ml C3G) was inhibited by 17.43%, 34.98%, and 63.38%, respectively. The IC₅₀ values for DDP and the DDP/C3G combination treatments in HeLa cells were 18.53 and 6.435 µg/ml, respectively. Flow cytometry analysis indicated that treatment with DDP, C3G, or the combination induced G1 cell cycle arrest and apoptosis in HeLa cells. Furthermore, after treatment, cyclin D1 and Bcl-2 levels decreased; Bax, cleaved caspase-3, p53, and TIMP-1 were activated; and the PI3K/AKT/mTOR signaling pathway was modulated. These anticancer effects were enhanced in cells treated with the combination of DDP and C3G compared to those treated with DDP or C3G alone. Our study indicates that C3G increases the antitumor activity of DDP, suggesting a potential strategy to reduce adverse effects associated with chemotherapy in cervical cancer. PRACTICAL APPLICATION: Natural biologically active food ingredients are suggested to have a potential to enhance the effect of chemotherapy in cancer. We believe that our study makes a significant contribution to the literature because it revealed, for the first time, that C3G could increase the antitumor activity of DDP, suggesting a potential strategy to reduce adverse effects associated with chemotherapy in cervical cancer.

In Vivo and In Vitro Effects of Tracheloside on Colorectal Cancer Cell Proliferation and Metastasis

Recent research suggests a relationship between cancer progression and oxidative mechanisms. Among the phenolic compounds such as tracheloside (TCS) are a major bioactive compound that can combat oxidant stress-related chronic diseases and that also displays anti-tumor activity. Although TCS can inhibit mammalian carcinoma, its effects on colorectal cancer (CRC) have not been clarified. The purpose of this study was to investigate the effects of TCS on the proliferation of CRC cells, the metastasis of CT26 cells, and the molecular mechanisms related to TCS in vitro and in vivo. A cell viability assay showed that TCS inhibited the proliferation of CRC cells. TCS-treated CT26 cells were associated with the upregulation of p16 as well as the downregulation of cyclin D1 and CDK4 in cell cycle arrest. In addition, TCS induced apoptosis of CT26 cells through mitochondria-mediated apoptosis and regulation of the Bcl-2 family. Expression of epithelial–mesenchymal transition (EMT) markers was regulated by TCS treatment in CT26 cells. TCS significantly inhibited the lung metastasis of CT26 cells in a mouse model. These results suggest that TCS, by inducing cell cycle arrest and apoptosis through its anti-oxidant properties, is a novel therapeutic agent that inhibits metastatic phenotypes of murine CRC cells.

A novel patient-derived orthotopic xenograft (PDOX) mouse model of highly-aggressive liver metastasis for identification of candidate effective drug-combinations

Liver metastasis is a recalcitrant disease that usually leads to death of the patient. The present study established a unique patient-derived orthotopic xenograft (PDOX) nude mouse model of a highly aggressive liver metastasis of colon cancer. The aim of the present study was to demonstrate proof-of-concept that candidate drug combinations could significantly inhibit growth and re-metastasis of this recalcitrant tumor. The patient’s liver metastasis was initially established subcutaneously in nude mice and the subcutaneous tumor tissue was then orthotopically implanted in the liver of nude mice to establish a PDOX model. Two studies were performed to test different drugs or drug combination, indicating that 5-fluorouracil (5-FU) + irinotecan (IRI) + bevacizumab (BEV) and regorafenib (REG) + selumetinib (SEL) had significantly inhibited liver metastasis growth (p = 0.013 and p = 0.035, respectively), and prevented liver satellite metastasis. This study is proof of concept that a PDOX model of highly aggressive colon-cancer metastasis can identify effective drug combinations and that the model has future clinical potential.

Biodistribution, pharmacokinetics, and organ-level dosimetry for 188Re-AHDD-Lipiodol radioembolization based on quantitative post-treatment SPECT/CT scans

Background

Rhenium-188-labelled-Lipiodol radioembolization is a safe and cost-effective treatment for primary liver cancer. In order to determine correlations between treatment doses and patient response to therapy, accurate patient-specific dosimetry is required. Up to date, the reported dosimetry of ¹⁸⁸Re-Lipiodol has been based on whole-body (WB) planar imaging only, which has limited quantitative accuracy. The aim of the present study is to determine the in vivo pharmacokinetics, bio-distribution, and organ-level dosimetry of ¹⁸⁸Re-AHDD-Lipiodol radioembolization using a combination of post-treatment planar and quantitative SPECT/CT images. Furthermore, based on the analysis of the pharmacokinetic data, a practical and relatively simple imaging and dosimetry method that could be implemented in clinics for ¹⁸⁸Re-AHDD-Lipiodol radioembolization is proposed.

Thirteen patients with histologically proven hepatocellular carcinoma underwent ¹⁸⁸Re-AHDD-Lipiodol radioembolization. A series of 2–3 WB planar images and one SPECT/CT scan were acquired over 48 h after the treatment. The time-integrated activity coefficients (TIACs, also known as residence-times) and absorbed doses of tumors and organs at risk (OARs) were determined using a hybrid WB/SPECT imaging method.

Results

Whole-body imaging showed that ¹⁸⁸Re-AHDD-Lipiodol accumulated mostly in the tumor and liver tissue but a non-negligible amount of the pharmaceutical was also observed in the stomach, lungs, salivary glands, spleen, kidneys, and urinary bladder. On average, the measured effective half-life of ¹⁸⁸Re-AHDD-Lipiodol was 12.5 ± 1.9 h in tumor. The effective half-life in the liver and lungs (the two organs at risk) was 12.6 ± 1.7 h and 12.0 ± 1.9 h, respectively. The presence of ¹⁸⁸Re in other organs was probably due to the chemical separation and subsequent release of the free radionuclide from Lipiodol.

The average doses per injected activity in the tumor, liver, and lungs were 23.5 ± 40.8 mGy/MBq, 2.12 ± 1.78 mGy/MBq, and 0.11 ± 0.05 mGy/MBq, respectively. The proposed imaging and dosimetry method, consisting of a single SPECT/CT for activity determination followed by ¹⁸⁸Re-AHDD-Lipiodol clearance with the liver effective half-life of 12.6 h, resulted in TIACs estimates (and hence, doses) mostly within ± 20% from the reference TIACs (estimated using three WB images and one SPECT/CT).

Conclusions

The large inter-patient variability of the absorbed doses in tumors and normal tissue in ¹⁸⁸Re-HDD-Lipiodol radioembolization patients emphasizes the importance of patient-specific dosimetry calculations based on quantitative post-treatment SPECT/CT imaging.

Electronic supplementary material

The online version of this article (10.1186/s40658-018-0227-6) contains supplementary material, which is available to authorized users.

Induction of apoptosis by Dae-Hwang-Mok-Dan-Tang in HCT-116 colon cancer cells through activation of caspases and inactivation of the phosphatidylinositol 3-kinase/Akt signaling

BACKGROUND

Dae-Hwang-Mok-Dan-Tang (DHMDT), a traditional Korean medicine, contains five species of medicinal plants and has been used to treat patients with digestive tract cancer for hundreds of years; however, its anticancer mechanism is poorly understood. In the present study, we investigated the proapoptotic effects of DHMDT in human colon cancer HCT-116 cells.

METHODS

Cytotoxicity was evaluated using the 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2H-tetrazolium bromide assay. Apoptosis was detected using 4,6-diamidino-2-phenyllindile staining, agarose gel electrophoresis, and flow cytometry. The protein levels were determined using Western blot analysis. Caspase activity was measured using a colorimetric assay.

RESULTS

Treatment with DHMDT resulted in a growth inhibition coupled with apoptosis induction, which was associated with the downregulation of members of IAP (inhibitor of apoptosis protein) family, including XIAP and survivin, and the activation of caspase-9 and -3 accompanied by proteolytic degradation of poly(ADP-ribose)-polymerase and phospholipase C-γ1. DHMDT treatment also showed a correlation with the translocation of proapoptotic Bax to mitochondria, the loss of mitochondrial membrane permeabilization, and the cytochrome c release from the mitochondria to the cytosol. Moreover, DHMDT increased the levels of death receptor-associated ligands and enhanced activation of caspase-8 and cleavage of its substrate, Bid. However, the pan-caspase inhibitor could reverse DHMDT-induced apoptosis. In addition, DHMDT suppressed the phosphoinositide 3-kinase (PI3K)/Akt pathway, and treatment with a potent inhibitor of PI3K further increased the apoptotic activity of DHMDT.

CONCLUSION

Our data showed that DHMDT induces HCT-116 cell apoptosis by activating intrinsic and extrinsic apoptosis pathways and by suppressing the PI3K/Akt signal pathway; however, further studies are needed to identify the active compounds.

Hepatic Lesions that Mimic Metastasis on Radiological Imaging during Chemotherapy for Gastrointestinal Malignancy: Recent Updates

During chemotherapy in patients with gastrointestinal malignancy, the hepatic lesions may occur as chemotherapy-induced lesions or tumor-associated lesions, with exceptions for infectious conditions and other incidentalomas. Focal hepatic lesions arising from chemotherapy-induced hepatopathies (such as chemotherapy-induced sinusoidal injury and steatosis) and tumor-associated eosinophilic abscess should be considered a mimicker of metastasis in patients with gastrointestinal malignancy. Accumulating evidence suggests that chemotherapy for gastrointestinal malignancy in the liver has roles in both the therapeutic effects for hepatic metastasis and injury to the non-tumor bearing hepatic parenchyma. In this article, we reviewed the updated concept of chemotherapy-induced hepatopathies and tumor-associated eosinophilic abscess in the liver, focusing on the pathological and radiological findings. Awareness of the causative chemo-agent, pathophysiology, and characteristic imaging findings of these mimickers is critical for accurate diagnosis and avoidance of unnecessary exposure of the patient to invasive tissue-based diagnosis and operations.

Novel ent-Kaurane Diterpenoid from Rubus corchorifolius L. f. Inhibits Human Colon Cancer Cell Growth via Inducing Cell Cycle Arrest and Apoptosis

The tender leaves of Rubus corchorifolius L. f. have been consumed as tea for drinking in China since ancient times. In this study, a novel ent-kaurane diterpenoid was isolated and identified from R. corchorifolius L. f. leaves as ent-kaur-2-one-16β,17-dihydroxy-acetone-ketal (DEK). DEK suppressed the growth of HCT116 human colon cancer cells with an IC₅₀ value of 40 ± 0.21 μM, while it did not cause significant growth inhibition on CCD-18Co human colonic myofibroblasts at up to100 μM. Moreover, DEK induced extensive apoptosis and S phase cell cycle arrest in the colon cancer cells. Accordingly, DEK caused profound effects on multiple signaling proteins associated with cell proliferation, cell death, and inflammation. DEK significantly upregulated the expression levels of pro-apoptotic proteins such as cleaved caspase-3, cleaved caspase-9, cleaved PARP, p53, Bax, and tumor suppressor p21^Cip1/Waf1, downregulated the levels of cell cycle regulating proteins such as cyclinD1, CDK2, and CDK4 and carcinogenic proteins such as EGFR and COX-2, and suppressed the activation of Akt. Overall, our results provide a basis for using DEK as a potential chemopreventive agent against colon carcinogenesis.

Magnetic Resonance Imaging of Liver Metastasis

Liver magnetic resonance imaging (MRI) is becoming the gold standard in liver metastasis detection and treatment response assessment. The most sensitive magnetic resonance sequences are diffusion-weighted images and hepatobiliary phase images after Gd-EOB-DTPA. Peripheral ring enhancement, diffusion restriction, and hypointensity on hepatobiliary phase images are hallmarks of liver metastases. In patients with normal ultrasonography, computed tomography (CT), and positron emission tomography (PET)-CT findings and high clinical suspicion of metastasis, MRI should be performed for diagnosis of unseen metastasis. In melanoma, colon cancer, and neuroendocrine tumor metastases, MRI allows confident diagnosis of treatment-related changes in liver and enables differential diagnosis from primary liver tumors. Focal nodular hyperplasia-like nodules in patients who received platinum-based chemotherapy, hypersteatosis, and focal fat can mimic metastasis. In cancer patients with fatty liver, MRI should be preferred to CT. Although the first-line imaging for metastases is CT, MRI can be used as a problem-solving method. MRI may be used as the first-line method in patients who would undergo curative surgery or metastatectomy. Current limitation of MRI is low sensitivity for metastasis smaller than 3mm. MRI fingerprinting, glucoCEST MRI, and PET-MRI may allow simpler and more sensitive diagnosis of liver metastasis.

Clinical efficacy and drug resistance of anti-epidermal growth factor receptor therapy in colorectal cancer

Colorectal cancer (CRC) ranked third in cancer related death and its incidence has been increasing worldwide. In recent decades important therapeutic advances have been developed in treatment of metastatic CRC (mCRC), such as monoclonal antibodies against epidermal growth factor receptor (anti-EGFR), which provided additional clinical benefits in mCRC. However, anti-EGFR therapies have limited usage due to approximately 95% of patients with KRAS mutated mCRC do not response to anti-EGFR treatment. Thus, KRAS mutation is predictive of nonresponse to anti-EGFR therapies but it alone is not a sufficient basis to decide who should not be received such therapies because; approximately fifty percent (40%-60%) of CRC patients with wild-type KRAS mutation also have poor response to anti-EGFR based treatment. This fact leads us to suspect that there must be other molecular determinants of response to anti-EGFR therapies which have not been identified yet. Current article summarizes the clinical efficacy of anti-EGFR therapies and also evaluates its resistance mechanisms.

Chemotherapeutic agents attenuate CXCL12-mediated migration of colon cancer cells by selecting for CXCR4-negative cells and increasing peptidase CD26

Background

Recurrence of colorectal cancer (CRC) may arise due to the persistence of drug-resistant and cancer-initiating cells that survive exposure to chemotherapy. Proteins responsible for this recurrence include the chemokine receptor CXCR4, which is known to enable CRC metastasis, as well as the cancer-initiating cell marker and peptidase CD26, which terminates activity of its chemokine CXCL12.

Methods

We evaluated the expression and function of CXCR4 and CD26 in colon cancer cell lines and xenografts following treatment with common chemotherapies using radioligand binding, flow cytometry, immunofluorescence, and enzymatic assays.

Results

5-Fluorouracil, oxaliplatin and SN-38 (the active metabolite of irinotecan), as well as cisplatin, methotrexate and vinblastine, each caused decreases in cell-surface CXCR4 and concomitant increases in CD26 on HT-29, T84, HRT-18, SW480 and SW620 CRC cell lines. Flow cytometry indicated that the decline in CXCR4 was associated with a significant loss of CXCR4+/CD26- cells. Elevations in CD26 were paralleled by increases in both the intrinsic dipeptidyl peptidase activity of CD26 as well as its capacity to bind extracellular adenosine deaminase. Orthotopic HT-29 xenografts treated with standard CRC chemotherapeutics 5-fluorouracil, irinotecan, or oxaliplatin showed dramatic increases in CD26 compared to untreated tumors. Consistent with the loss of CXCR4 and gain in CD26, migratory responses to exogenous CXCL12 were eliminated in cells pretreated with cytotoxic agents, although cells retained basal motility. Analysis of cancer-initiating cell CD44 and CD133 subsets revealed drug-dependent responses of CD26/CD44/CD133 populations, suggesting that the benefits of combining standard chemotherapies 5-fluoruracil and oxaliplatin may be derived from their complementary elimination of cell populations.

Conclusion

Our results indicate that conventional anticancer agents may act to inhibit chemokine-mediated migration through eradication of CXCR4+ cells and attenuation of chemokine gradients through elevation of CD26 activity.

Electronic supplementary material

The online version of this article (doi:10.1186/s12885-015-1702-2) contains supplementary material, which is available to authorized users.

Significant Shrinkage of Multifocal Liver Metastases and Long-Term Survival in a Patient With Rectal Cancer, After Trans-Arterial Chemoembolization (TACE): A Case Report

In this paper, we present the successful therapeutic approach of unresectable liver metastases in a patient with rectal cancer.A 63-year-old male underwent endoscopic polypectomy followed by rectosigmoid resection for an adenocarcinoma of the rectum diagnosed in pT2N0 stage. The angio-computed tomography (CT) revealed four metastatic hepatic nodules ranging from 12 to 130 mm in diameter. After one cure of trans-arterial chemoembolization (TACE) with lipiodol and 5-fluorouracil, combined with FOLFOX4 + capecitabine systemic chemotherapy, the diameter of all hepatic nodules decreased to half size, at 6 months after TACE. Further curative surgical hepatic metastasectomy was done and complete pathologic response was obtained. The patient is free of recurrences and metastases after 26 months of follow-up.This representative case shows that an efficient trans-disciplinary approach could lead to successful therapeutic management even in patients with advanced-staged colorectal carcinomas.

Detection of K-ras Mutations in Predicting Efficacy of Epidermal Growth Factor Receptor Tyrosine Kinase (EGFR-TK) Inhibitor in Patients with Metastatic Colorectal Cancer

Epidermal growth factor receptor tyrosine kinase (EGFR-TK) inhibitors are useful in treating different advanced human cancers; however, their clinical efficacy varies. This study detected K-ras mutations to predict the efficacy of EGFR-TK inhibitor cetuximab treatment on Chinese patients with metastatic colorectal cancer (mCRC). A total of 87 patients with metastatic colorectal cancer were treated with cetuximab for 2-16 months, in combination with chemotherapy between August 2008 and July 2012, and tissue samples were used to detect K-ras mutations. The data showed that K-ras mutation occurred in 27/87 (31%). The objective response rates and disease control rate in K-ras wild type and mutant patients were 42% (25/60) versus 11% (3/27) (p<0.05) and 60% (36/60) versus 26% (7/27) (p<0.05), respectively. Patients with the wild-type K-ras had significantly higher median survival times and progression-free survival, than patients with mutated K-ras (21 months versus 17 months, p=0.017; 10 months versus 6 months, p=0.6). These findings suggest that a high frequency of K-ras mutations occurs in Chinese mCRC patients and that K-ras mutation is required to select patients for eligibility for cetuximab therapy. Further prospective studies using a large sample size are needed to confirm these preliminary findings.

Hepatic metastases of colorectal cancer are rather homogeneous but differ from primary lesions in terms of immune cell infiltration

The immune system plays an important role in shaping the clinical course of colorectal cancer (CRC). However, it is still unclear how the immune infiltrates of primary CRC lesions and distant metastases by immune effector cells are related to each other. To address this issue, we quantified CD3⁺, CD8⁺ and granzyme B⁺ lymphocytes in primary CRC samples and corresponding liver metastases. This analysis showed that the prognostic predictions that can be drawn from the infiltration of immune cells in primary CRCs and their metastases are heterogeneous. To investigate whether such heterogeneity would also be observed within CRC hepatic metastases, the density of the immune infiltrate and cytokine production were assessed in opposite sides of the same metastatic lesion. In addition, tumor-infiltrating lymphocytes were assessed in sequential sections of the same metastatic lesion, with a spacing of 30 μm. In summary, consistent cell counts and cytokine levels were detected within the same lesion. The study of a case of synchronous metastases, however, suggested that different metastatic lesions within the same patient may be heterogeneous, perhaps indicating a major impact for local causes on tumor infiltration by immune cells. In summary, our study demonstrates a consistent degree of heterogeneity between primary tumors and hepatic metastases but an excellent intra-lesional homogeneity. These findings may be of key importance for patient stratification and the development of personalized strategies against CRC.

Polymeric micelles loaded with platinum anticancer drugs target preangiogenic micrometastatic niches associated with inflammation

Nanocarriers have been used for specific delivery of therapeutic agents to solid tumors based on the enhanced permeability and retention in cancerous tissues. Despite metastasis is the main reason of cancer-related death and a priority for nanocarrier-based therapies, the targeting ability of nanocarriers to the metastatic disease is poorly understood, especially for preangiogenic micrometastases as nanocarriers usually use the malignant neovasculature for enhancing their accumulation. Thus, herein, we studied the ability of micellar nanocarriers incorporating (1,2-diaminocyclohexane)platinum(II) (DACHPt) for treating liver metastases of bioluminescent murine colon adenocarcinoma C-26, during overt and preangiogenic metastatic stages. After intravenous injection, DACHPt-loaded micelles (DACHPt/m) effectively inhibited the tumor growth in both metastatic tumor models. While the anticancer activity of the micelles against overt metastases was associated with their selective accumulation in cancerous tissues having neovasculature, the ability of DACHPt/m to target preangiogenic metastases was correlated with the inflammatory microenvironment of the niche. This targeting capability of polymeric micelles to preangiogenic metastasis may provide a novel approach for early diagnosis and treatment of metastases.

Chemotherapy-induced focal hepatopathy in patients with gastrointestinal malignancy: gadoxetic acid--enhanced and diffusion-weighted MR imaging with clinical-pathologic correlation

PURPOSE

To retrospectively evaluate findings of chemotherapy-induced focal hepatopathy (CIFH) on gadoxetic acid-enhanced magnetic resonance (MR) and diffusion-weighted (DW) images and to determine imaging features that are most helpful in differentiating CIFH from metastasis.

MATERIALS AND METHODS

This retrospective study was approved by the institutional review board, and informed consent was waived. MR images, including DW images and gadoxetic acid-enhanced images, from 12 patients (four men, eight women; age range, 25-64 years) with 15 CIFHs were reviewed independently and in consensus by two radiologists and were compared with those obtained in 20 control patients (12 men, eight women; age range, 32-84 years) with 30 hepatic metastasis who were matched for tumor size, primary organ, and chemotherapy regimen. Interobserver agreement was assessed with κ statistics, and univariate analysis was performed for comparisons. For quantitative analyses, apparent diffusion coefficients (ADCs) and lesion-to-liver contrast ratios (CRs) were measured. Histopathologic examinations were performed for CIFHs.

RESULTS

Histopathologic examination revealed that the development of CIFHs was attributable to accentuated manifestations of sinusoidal obstruction syndrome. Interobserver agreement was excellent (κ > 0.85). An ill-defined margin on hepatobiliary phase (HBP) images was the most discriminating independent variable in the differentiation of CIFH from metastasis (odds ratio, 16; P = .009). ADC and CR values in CIFH group were significantly higher than those in metastasis group (P < .001 and P = .041).

CONCLUSION

CIFH should be considered a mimicker of metastasis in patients with gastrointestinal malignancy during chemotherapy. CIFH can be differentiated from metastasis on the basis of gadoxetic acid-enhanced MR and DW imaging findings; an ill-defined margin on HBP images was especially characteristic.

Yttrium-90 microsphere-selective internal radiation therapy with chemotherapy (chemo-SIRT) for colorectal cancer liver metastases: an in vivo double-arm-controlled phase II trial

OBJECTIVES

Selective internal radiation therapy (SIRT) with yttrium-90 (Y) microspheres has emerged as an effective liver-directed therapy with a favorable therapeutic ratio for treatment of colorectal cancer liver metastases. The aim of this study was to investigate the objective responses obtained by Y microsphere treatment when combined with contemporary chemotherapy in the front-line (first or second line) setting in patients with CRCLM.

METHODS

This study used an in vivo comparison between the right and left liver lobes; systemic chemotherapy was supplied to both liver lobes by virtue of systemic administration, whereas SIRT was administered selectively to the target liver lobe only. Response to treatment was evaluated by serial fludeoxyglucose positron emission tomography computed tomography performed at 4 weeks, 2 to 4 months, and 6 to 8 months. Standard uptake value, anatomic volume, functional tumor volume, and total lesion glycolysis (TLG) calculations were obtained at each time point.

RESULTS

A decrease in TLG on fludeoxyglucose positron emission tomography computed tomography imaging was seen in 19 of the 20 patients. The mean decrease in TLG values in the tumors receiving chemo-SIRT and chemo-only treatment were 86.26%±18.57% and 31.74%±80.99% (P<0.01), 93.13%±11.81% and 40.80%±73.32% (P=0.01), and 90.55%±19.75% and 54.91%±38.55% (P<0.01) at 4 weeks, 2 to 4 months, 6 to 8 months posttreatment, respectively. Functional and anatomic tumor volume changes were in concordance with the TLG changes.

CONCLUSIONS

The study demonstrated that, under near identical conditions in terms of patient and tumor characteristics, the chemo-SIRT combination produced superior objective responses compared with chemo-only treatment in a front-line treatment setting in patients with colorectal cancer liver metastases.

Analysis of PTEN, BRAF and PI3K status for determination of benefit from cetuximab therapy in metastatic colorectal cancer patients refractory to chemotherapy with wild-type KRAS

We investigated predictive values of BRAF, PI3K and PTEN in cetuximab responses in KRAS wild-type (+) chemotherapy refractory, metastatic colorectal cancer (CRC) patients. Primary tumour tissues of 41 KRAS wild-type mCRC patients receiving cetuximab-based chemotherapy were investigated for PI3K, PTEN, KRAS and BRAF mutations. Progression-free survival (PFS) and overall survival (OS) periods were calculated with Kaplan-Meier method and the Cox proportional hazards model was used. PTEN and PI3K expressions were 63 and 42 %, respectively. BRAF mutation was observed as 9.8 % among patients. Tumours with BRAF mutation had statistically lower response rates (RR) for cetuximab-based treatment than tumours with BRAF wild type (0 vs. 58 %, p = 0.02). PTEN expressing tumours had statistically higher RR for cetuximab-based treatment than tumours with PTEN loss (42 vs. 12 %, p = 0.04). PI3K expression had worse significant effect on cetuximab RR than PI3K non-expressed tumours (15 vs. 44 %, p = 0.023). Median PFS was significantly longer in patients with PTEN expression (14 months) than in patients with PTEN loss (5 months) (HR, 0.4; p = 0.028). Median PFS was significantly longer in patients with PI3K non-expression (15.2 months) than in patients with PI3K expression (4.1 months) (HR, 0.31; p = 0.001). Significant difference in PFS and OS between patients with BRAF mutated and BRAF wild-type tumours was not detected. However, patients with PTEN expression had significantly longer OS (15.1 months) than patients with PTEN loss tumour (9.9 months) (HR, 0.34; p = 0.008). Patients without PI3K expression had significantly longer OS (18.2 months) than patients with PI3K expression (10.1 months) (HR, 0.27; p = 0.001). Multivariate analyses revealed that PTEN expression (HR, 0.48; p = 0.02) and absence of PI3K expression (HR, 0.2; p = 0.001) were independent prognostic factors for increased PFS. Similarly, PTEN overexpression (HR, 0.62; p = 0.03) and absence of PI3K expression (HR, 0.27; p = 0.005) were independent prognostic factors for increased OS. In PTEN loss, PI3K expression may be used as biomarkers to further select KRAS wild-type patients undergoing anti-epidermal growth factor receptor treatment.

Association of decreased mitochondrial DNA content with the progression of colorectal cancer

Background

Experimental data suggest that mitochondria is involved in tumorigenesis. However, little is known about the qualitative and quantitative changes of mtDNA in colorectal cancer tissues. We therefore conducted possible correlations of the mitochondrial DNA (mtDNA) copy number in colorectal cancer (CRC) with clinical and pathological findings and CRC prognosis.

Methods

mtDNA copy numbers in CRC cancer tissue and adjacent non-cancerous tissue samples were measured using quantitative real-time polymerase chain reaction analyses from 60 patients admitted to our hospital. We examined the correlation of mtDNA copy numbers and clinicopathologic parameters of CRC patients. The correlation between mtDNA copy number and three-year survival was analyzed.

Results

The mtDNA copy number was lower in CRC tissue compared with the corresponding non-cancerous colorectal tissue (mean: 108.60 ± 20.11 vs. 153.68 ± 25.72) and was significantly correlated with lymph-node metastasis. Patients with a lower mtDNA copy number tended to have lower 3-year survival than patients with a higher mtDNA copy number assessed by Kaplan–Meier curves, but the correlation was not significant (overall survival, 63.0 vs 83%).

Conclusions

These results suggest that a reduced copy number of mtDNA is correlated with malignant potential in CRC.

Transarterial chemoembolization of hepatocellular carcinoma. Agents and drugs: an overview. Part 1

INTRODUCTION

Hepatocellular carcinoma (HCC) is one of the most common lethal malignancies. The prognosis is poor despite progress in early diagnosis. The initial treatment of choice is hepatic resection; unfortunately, not all patients are eligible for liver resection. Moreover, there are significant recurrences. Different liver-directed therapies have been developed to increase the number of patients eligible for liver resection. Among them, transarterial chemoembolization (TACE) is a technique of improving importance that involves the intra-arterial administration of anticancer drugs and embolization agents into the liver tumor. In the first part of this review, an overview of the present situation in the field of TACE has been made, referring in particular to the use of Lipiodol.

AREAS COVERED

Clinical overview of TACE with attention to the present limits and problems of this technique.

EXPERT OPINION

The use of TACE techniques is important in the treatment of HCCs. However, this technique needs to be improved in particular taking into account the use of new materials for the preparation of embolizing agents able to control the drug release.

Classifying the stage IV colorectal cancer: prognostic impact of radical resection for colorectal liver metastases and proposal for a new staging system

Currently, there is no universally accepted system to classify the stage IV colorectal cancer. Here, we analyze the prognostic impact of radical resection for colorectal liver metastases and propose a new staging system for stage IV colorectal cancer. A retrospective review was undertaken of 126 consecutive patients who underwent surgical treatment for colorectal liver metastases from January 1997 to January 2004. Based on the overall survival rates (Kaplan-Meier method) and surgical outcomes, we propose a new staging system for stage IV colorectal cancer. Patients were divided into two groups: patients who underwent initial hepatic resections (R0 resection) for liver metastases (group 1, n = 22), and patients who underwent palliative resection for unresectable liver metastases (group 2, n = 104). The overall survival rates in group 1 at 1, 3, and 5 years were 68.2% (15/22), 40.9% (9/22), and 18.2% (4/22), respectively. The overall survival rates in group 2 at 1, 3, and 5 years were 54.8% (57/104), 16.3% (17/104), and 0% (0/104), respectively. There was a significant difference in overall survival rates between both groups (p < 0.05). Based on the study results, we propose a new staging system where all distant metastases are grouped within stage IV and subclassified into resectable (R0 resection) and unresectable stages. Curative surgical treatment is a critical prognostic factor in colorectal liver metastases. The proposed new staging system for stage IV colorectal cancer is simple and is clinically useful to estimate the prognosis.

Contrast agents as a biological marker in magnetic resonance imaging of the liver: conventional and new approaches

Liver imaging is an important clinical area in everyday practice. The clinical meaning of different lesion types in the liver can be quite different. Therefore, the result of imaging studies of the liver can change therapeutic concepts fundamentally. Contrast agents are used in the majority of MR examinations of the liver parenchyma-despite the already good soft-tissue contrast in plain MRI. This can be explained by the advantages in lesion detection and characterization of contrast-enhanced MRI of the liver. Beyond the qualitative evaluation of contrast-enhanced liver MR examinations, quantification of parameters will be the demand of the future. This can be achieved by perfusion MRI, also called dynamic contrast-enhanced MRI (DCE-MRI) of the liver. Its basic principles and different clinical applications will be discussed in this article. Definite cut-off values to determine disease or therapeutic response will help to increase the objectivity and reliability of liver MRI in future. This is especially important in the oncological setting, where modern therapies cannot be assessed based on changes in size only.

ID1 and ID3 regulate the self-renewal capacity of human colon cancer-initiating cells through p21

There is increasing evidence that some cancers are hierarchically organized, sustained by a relatively rare population of cancer-initiating cells (C-ICs). Although the capacity to initiate tumors upon serial transplantation is a hallmark of all C-ICs, little is known about the genes that control this process. Here, we establish that ID1 and ID3 function together to govern colon cancer-initiating cell (CC-IC) self-renewal through cell-cycle restriction driven by the cell-cycle inhibitor p21. Regulation of p21 by ID1 and ID3 is a central mechanism preventing the accumulation of excess DNA damage and subsequent functional exhaustion of CC-ICs. Additionally, silencing of ID1 and ID3 increases sensitivity of CC-ICs to the chemotherapeutic agent oxaliplatin, linking tumor initiation function with chemotherapy resistance.

Efficacy of oxaliplatin-based chemotherapy in curatively resected colorectal cancer with liver metastasis

OBJECTIVES

Although surgical resection alone has been validated as a standard treatment for patients with liver metastases from colorectal cancer, a high rate of recurrence is still an issue to be overcome. We aimed to assess the efficacy of adjuvant chemotherapy using an oxaliplatin-based regimen in patients who underwent hepatic and primary colorectal cancer resection.

METHODS

Sixty patients who received oxaliplatin-based postoperative chemotherapy combined with curative resection of primary colorectal cancer and synchronous liver metastases between January 2000 and February 2008 were retrospectively reviewed. The Kaplan-Meier method was used to estimate survival, and prognostic factors were evaluated with the log-rank test.

RESULTS

Median overall survival (OS) was 62.8 months [95% confidence interval (CI) 44.1-81.3], and median relapse-free survival (RFS) was 32.8 months (95% CI 5.8-59.6). The 1-, 3- and 5-year survival rates were 95.0, 68.8 and 55.5%, respectively. The relapse-free interval and modality of liver resection were independently associated with OS.

CONCLUSIONS

Oxaliplatin-based adjuvant chemotherapy after radical resection resulted in increased OS and RFS with acceptable tolerability compared to surgery alone. However, it is not yet clear whether postoperative oxaliplatin-based chemotherapy improves outcome compared to patients treated with 5-fluorouracil plus leucovorin.

Differentiated human colorectal cancer cells protect tumor-initiating cells from irinotecan

BACKGROUND & AIMS

Stem cells of normal tissues have resistance mechanisms that allow them to survive genotoxic insults. The stem cell-like cells of tumors are defined by their tumor-initiating capacity and may have retained these resistance mechanisms, making them resistant to chemotherapy. We studied the relationship between resistance to the topoisomerase I inhibitor irinotecan and tumor-initiating potential in human colonosphere cultures and in mice with colorectal xenograft tumors.

METHODS

Colonosphere cultures were established from human colorectal tumor specimens obtained from patients who underwent colon or liver resection for primary or metastatic adenocarcinoma. Stem cell and differentiation markers were analyzed by immunoblotting and fluorescence-activated cell sorting. Clone- and tumor-initiating capacities were assessed by single-cell cloning and in immune-deficient mice. Sensitivity to irinotecan was assessed in vitro and in tumor-bearing mice. The relationship between drug resistance and tumor-initiating capacity was tested by fluorescence-activated cell sorting of colonosphere cells, based on expression of ABCB1 and aldehyde dehydrogenase (ALDH) activity.

RESULTS

Colonosphere cultures had a high capacity to initiate tumors in mice and were resistant to irinotecan. Inhibition of the drug-efflux pump ABCB1 by PSC-833 allowed irinotecan to eradicate tumor-initiating cells. However, ABCB1 was expressed only by a subpopulation of differentiated tumor cells that did not form clones or tumors. Conversely, tumor-initiating cells were ABCB1-negative and were identified by high ALDH activity. Tumorigenic ALDHhigh/ABCB1negative cells generated nontumorigenic ALDHlow/ABCB1positive daughter cells in vitro and in tumor xenografts. PSC-833 increased the antitumor efficacy of irinotecan in mice.

CONCLUSIONS

The resistance of colorectal tumors to irinotecan requires the cooperative action of tumor-initiating ALDHhigh/ABCB1negative cells and their differentiated, drug-expelling, ALDHlow/ABCB1positive daughter cells.

Methylenetetrahydrofolate reductase polymorphism (677 C>T) predicts long time to progression in metastatic colon cancer treated with 5-fluorouracil and folinic acid

BACKGROUND AND AIMS

Fluoropyrimidine-based chemotherapy is the most common treatment for unresectable metastatic colorectal cancer (m-CRC). Therapy with 5-FU/folinic acid (FA) continues to be a standard treatment in developing countries. Pharmacogenomics allows the tailoring of cancer therapy to the patient. The polymorphism 677C>T of the methylenetetrahydrofolate reductase (MTHFR) gene seems to influence the effectiveness of treatment with 5-FU. We undertook this study to evaluate the frequency of MTHFR 677C>T polymorphism and its relationship to the time to progression (TTP) and overall survival (OS) in m-CRC treated with 5-FU/FA.

METHODS

The MTHFR 677C>T polymorphism was determined using PCR and allele-specific digestion. The clinical variables, TTP and OS, were analyzed in each case and compared between wild-type and variant polymorphic groups.

RESULTS

Among 34 patients (12 males and 22 females), we detected eight wild-type homozygous patients (CC; 24%), nine variant homozygous (TT; 26%), and 17 heterozygous (CT; 50%) individuals. The median TTP in patients with the MTHFR 677 CC, CT, and TT genotypes was 3.43, 4.77, and 4.80 months, respectively (p = 0.047, log rank). A longer TTP was observed in patients with polymorphic variant (CT and TT) compared with the wild-type homozygous patients (4.80 vs. 3.43 months; p = 0.031, log rank).

CONCLUSIONS

In this study, the frequency of the MTHFR 677C>T polymorphism is 50% among m-CRC Mexican patients. The results of this study appear to show that the presence of the MTHFR 677C>T polymorphism is associated with longer TTP and OS in m-CRC treated with 5-FU/FA.

Colorectal liver metastases

BACKGROUND

Despite major advances in therapies for liver metastases, colorectal cancer remains one of the commonest causes of cancer-related deaths in the UK.

SOURCES OF DATA

The international literature on the management of colorectal liver metastases (CLM) was reviewed.

AREAS OF AGREEMENT

Due to a combination of highly active systemic agents and low perioperative mortality achieved by high-volume centres, a growing number of patients are being offered liver resection with curative intent. Patients with bilobar and/or extrahepatic disease who would previously have received palliative treatment only, are undergoing major surgery with good results. This review focuses on preoperative evaluation, surgical planning and the role of adjuvant therapies in the management of patients with CLM.

AREAS OF CONTROVERSY

Can ablative therapies match the outcomes of surgical resection? How can even more patients be rendered resectable?

GROWING POINTS

The use of other therapies, such as radiofrequency ablation and selective internal radiation therapy.

AREAS TIMELY FOR DEVELOPING RESEARCH

New chemotherapy regimens for neo-adjuvant therapy and the development of new modalities of liver tumour ablation.

Trans-arterial chemoembolization as a therapy for liver tumours: New clinical developments and suggestions for combination with angiogenesis inhibitors

The liver is the primary site of metastases for many malignancies. Gastrointestinal cancers are especially prone to spread to the liver and other tumours, as breast cancer and melanoma often spread to the liver. On the other hand, hepatocellular cancer (HCC) is the fifth most common malignancy in the world due to its common etiology from chronic liver damage caused by hepatitis or cirrhosis. Treatments of liver tumours vary according to histology and liver invasion and until now trans-arterial chemoembolization (TACE) has represented a main approach in the therapy of liver tumours. This review takes into consideration: (i) the background to utilizing TACE in liver tumours; (ii) TACE methods and the biological rationale for utilizing chemotherapeutic agents coated to a new micro-particle such as DC-Beads and HepaSphere; (iii) clinical experiences employing TACE in different liver tumours; (iv) the pivotal role of angiogenesis and hypoxia-induced angiogenesis following TACE with special references to HCC. Finally, the rationale for the combination of TACE with angiogenesis inhibitors is also discussed.

Chemotherapy for the conversion of unresectable colorectal cancer liver metastases to resection

Resection of colorectal liver metastases (CLM) is the ultimate aim of treatment strategies in most patients with liver-confined metastatic colorectal cancer. Long-term survival is possible in selected patients with initially resectable or unresectable CLM. As a majority of patients have unresectable liver disease at the outset, there is a clear role for chemotherapy to downstage liver disease making resection possible. Studies of systemic chemotherapy with or without biologic therapy in patients with unresectable CLM have resulted in increased response rates, liver resection rates and survival. A sound physiologic rationale exists for the use of hepatic arterial infusion (HAI) therapy. Studies have shown that HAI with floxuridine combined with systemic chemotherapy increases response rates and liver resection rates in those patients with initially unresectable CLM. Toxicity from preoperative chemotherapy, biologic therapy and HAI therapy may adversely affect hepatic resection but can be kept minimal with appropriate monitoring. All conversion strategies should be decided by a multidisciplinary team.

Predictors and survival of synchronous peritoneal carcinomatosis of colorectal origin: a population-based study

The aim of our study was to provide population-based data on incidence and prognosis of synchronous peritoneal carcinomatosis and to evaluate predictors for its development. Diagnosed in 1995-2008, 18,738 cases of primary colorectal cancer were included. Predictors of peritoneal carcinomatosis were analysed by multivariable logistic regression analysis. Median survival in months was calculated by site of metastasis. In the study period, 904 patients were diagnosed with synchronous peritoneal carcinomatosis (4.8% of total, constituting 24% of patients presenting with M1 disease). The risk of peritoneal carcinomatosis was increased in case of advanced T stage [T4 vs. T1,2: odds ratio (OR) 4.7, confidence limits 4.0-5.6), advanced N stage [N0 vs. N1,2: OR 0.2 (0.1-0.2)], poor differentiation grade [OR 2.1 (1.8-2.5)], younger age [<60 years vs. 70-79 years: OR 1.4 (1.1-1.7)], mucinous adenocarcinoma [OR 2.0 (1.6-2.4)] and right-sided localisation of primary tumour [left vs. right: OR 0.6 (0.5-0.7)]. Median survival of patients with peritoneum as single site of metastasis remained dismal [1995-2001: 7 (6-9) months; 2002-2008: 8 (6-11) months], contrasting the improvement among patients with liver metastases [1995-2001: 8 (7-9) months; 2002-2008: 12 (11-14) months]. To conclude, synchronous peritoneal metastases from colorectal cancer are more frequent among younger patients and among patients with advanced T stage, mucinous adenocarcinoma, right-sided tumours and tumours that are poorly differentiated. The prognosis of synchronous peritoneal carcinomatosis remains poor with a median survival of 8 months and even worse if concomitant metastases in other organs are present.

Quantitative methodology using CT for predicting survival in patients with metastatic colorectal carcinoma: a pilot study

OBJECTIVE

To develop a methodology which quantifies multiple changing lesion features resulting in an optimized computed tomography (CT) response score (CRS) for prediction of overall survival (OS) in response to treatment for metastatic colorectal carcinoma (MCRC).

SUBJECTS AND METHODS

This Health Insurance Portability and Accountability Act-compliant, institutional review board-approved retrospective study evaluated multiple changing imaging findings and their correlation with OS with a new methodology comparing the baseline and first post-treatment CT scans in 38 MCRC patients on last-line chemotherapy (cetuximab and irinotecan). Tumor size/enhancement changes and interval development of new lesions were quantified with either Likert-type scales (all parameters) or Response Evaluation Criteria in Solid Tumors (RECIST) (size change only). The most predictive parameters for OS were used to generate the CRS with an overall range of -3 (complete disappearance) to +2 (definite tumor increase). The Cox Hazard Ratio was used to assess prediction of survival. Reader agreement was evaluated by the kappa statistic.

RESULTS

Tumor size was the best predictor of OS using the Likert-type scale or RECIST. The CRS was not improved combining size change with other parameters. Use of the Likert-type scale resulted in predicting OS with a Cox hazard ratio of 1.697 (P=.0004) and good agreement (kappa=0.73, 95% CI=0.41-1.10) between observers with no significant difference using RECIST.

CONCLUSION

The methodology produces a CRS for MCRC predicting OS resulting from therapy which expands standard RECIST guidelines to allow critical evaluation of multiple additional imaging parameters. Size change alone was found to be the best parameter of those considered in terms of maximizing agreement and prediction of OS.

Dynamic contrast-enhanced MR imaging of the liver: current status and future directions

Dynamic contrast-enhanced magnetic resonance imaging (DCE-MR imaging) is emerging as a tool that can quantify changes in liver perfusion that occur in both diffuse and focal liver diseases. Recent data show promise for DCE-MR imaging of the liver in diagnosing fibrosis and cirrhosis before morphologic changes can be detected. It may also be valuable in the assessment of hepatocellular carcinoma and liver metastases. Acquisition parameters, postprocessing methods, applications, and recent results of DCE-MR imaging of the liver are also described. Finally, it reviews the limitations and future directions of DCE-MR imaging for liver applications.

Fluoropyrimidine-HAI (hepatic arterial infusion) versus systemic chemotherapy (SCT) for unresectable liver metastases from colorectal cancer

BACKGROUND

Although locoregional treatments such as hepatic arterial infusion (HAI) claim the advantage of delivering higher doses of anticancer agents directly into the metastatic organ as compared to systemic chemotherapy (SCT), the benefit in terms of overall survival (OS) is unclear. We quantitatively summarized the results of randomised controlled trials (RCT) comparing HAI to SCT for the treatment of unresectable liver metastatic disease from colorectal cancer (CRC).

OBJECTIVES

The aim of this work is to quantitatively summarize the results of RCT comparing HAI to SCT for the treatment of unresectable hepatic metastases from CRC.

SEARCH STRATEGY

A systematic review of reports published until September 2008 on the findings of RCT that compared HAI to SCT for the treatment of unresectable CRC liver metastases was performed by searching the MEDLINE, Embase, Cancerlit, Cochrane and GoogleScholar electronic databases as well as other databanks collecting information on clinical trials.

SELECTION CRITERIA

Inclusion criteria were patients with unresectable CRC liver metastases enrolled in RCT comparing HAI to SCT. The outcome measures were tumor response rate and overall survival.

DATA COLLECTION AND ANALYSIS

Two authors independently carried out study selection and assessment of methodological quality. A third author performed a concordance analysis in order to unravel potential systematic biases.

MAIN RESULTS

Ten RCT were identified that met the eligibility criteria. HAI regimens were based on floxuridine (FUDR), 5-fluorouracil or either one of these two fluoropyrimidines in eight and one RCT, respectively. SCT consisted of FUDR or 5-fluorouracil in three and seven RCT, respectively. By pooling the summary data, tumor response rate resulted 42.9% and 18.4% for HAI and SCT, respectively (RR = 2.26; 95% CI, 1.80 to 2.84; P < 0.0001). Mean weighted median OS times were 15.9 and 12.4 months for HAI and SCT, respectively: the meta-risk of death was not statistically different between the two treatment groups (HR = 0.90; 95% CI, 0.76 to 1.07; P = 0.24).

AUTHORS' CONCLUSIONS

Currently available evidence does not support the clinical or investigational use of fluoropyrimidine-based HAI alone for the treatment of patients with unresectable CRC liver metastases: in fact, the greater tumor response rate obtained with this HAI regimen does not translate into a survival advantage over fluoropyrimidine alone SCT.

Development of arterial blood supply in experimental liver metastases

In this study, we present a mechanism for the development of arterial blood supply in experimental liver metastases. To analyze the arterialization process of experimental liver metastases, we elucidated a few key questions regarding the blood supply of hepatic lobules in mice. The microvasculature of the mouse liver is characterized by numerous arterioportal anastomoses and arterial terminations at the base of the lobules. These terminations supply one hepatic microcirculatory subunit per lobule, which we call an arterial hepatic microcirculatory subunit (aHMS). The process of arterialization can be divided into the following steps: 1) distortion of the aHMS by metastasis; 2) initial fusion of the sinusoids of the aHMS at the tumor parenchyma interface; 3) fusion of the sinusoids located at the base of the aHMSs, which leads to the disruption of the vascular sphincter (burst pipe); 4) incorporation of the dilated artery and the fused sinusoids into the tumor; and 5) further development of the tumor vasculature (arterial tree) by proliferation, remodeling, and continuous incorporation of fused sinusoids at the tumor-parenchyma interface. This process leads to the inevitable arterialization of liver metastases above the 2000- to 2500-mum size, regardless of the origin and growth pattern of the tumor.