Liver metastases from colorectal cancer: how to best complement medical treatment with surgical approaches

Interleukin-6 Family of Cytokines in Cancers

Nine soluble ligands [interleukin-6 (IL-6), interleukin-11 (IL-11), leukemia inhibitory factor (LIF), oncostatin M (OSM), ciliary neurotrophic factor (CNTF), cardiotrophin-1 (CT-1), cardiotrophin-like cytokine, interleukin-27 (IL-27), and interleukin-31] share the ubiquitously expressed transmembrane protein-glycoprotein-130 beta-subunit (gp130) and thus form IL-6 family cytokines. Proteins that may be important for cancerogenesis, CT-1, IL-11, IL-27, LIF, OSM, and CNTF, belong to the superfamily of IL-6. Cytokines such as IL-6, IL-11, and IL-27 are better investigated in comparison with other members of the same family of cytokines, eg, CT-1. Gp130 is one of the main receptors through which these cytokines exert their effects. The clinical implication of understanding the pathways of these cytokines in oncology is that targeted therapy to inhibit or potentiate cytokine activity may lead to remission in some cases.

Newcastle disease virus expressing an angiogenic inhibitor exerts an enhanced therapeutic efficacy in colon cancer model

Newcastle disease virus (NDV)-mediated gene therapy is a promising new approach for treatment of cancer but shows limited anti-angiogenesis. VEGF-Trap plays a vital role in anti-angiogenesis. To enhance the anti-tumor effect of NDV, VEGF-Trap gene was incorporated into the genome of rNDV in this study (named rNDV-VEGF-Trap). Results showed that rNDV-VEGF-Trap reduced cell growth ratio by 85.37% and migration ratio by 87.9% in EA.hy926 cells. In vivo studies, rNDV-VEGF-Trap reduced tumor volume and weight of CT26-bearing mice by more than 3 folds. Immunohistochemistry analysis of CD34 showed rNDV-VEGF-Trap significantly decreased the number of vascular endothelial cells in the tumor tissues. Moreover, Western blot analysis demonstrated that treatment with rNDV-VEGF-Trap significantly decreased the phosphorylation levels of AKT, ERK1/2 and STAT3 and increased the expression levels of P53, BAX and cleaved caspase-3 in the tumor tissue. In addition, to evaluate the toxicity of rNDV-VEGF-Trap, serum chemistries were analyzed. The results showed that rNDV-VEGF-Trap caused insignificant changes of creatinine levels, alanine aminotransferase and aspartate transaminase. Furthermore, administration of rNDV-VEGF-Trap did not cause the diarrhoea, decreased appetite, weight decrease and haemorrhage of the experimental mice. These data suggest that rNDV-VEGF-Trap exhibits an enhanced inhibition of CT26-bearing mice by enhancing anti-angiogenesis and apoptosis and may be a potential candidate for carcinoma therapy especially for colon cancer.

Cardiotrophin-1 determines liver engraftment of syngenic colon carcinoma cells through an immune system-mediated mechanism

Cardiotrophin-1 (CT-1/CTF1) is a member of the interleukin-6 (IL-6) family of cytokines that stimulates STAT-3 phosphorylation in cells bearing the cognate receptor. We report that Ctf1^−/− mice (hereby referred to as CT-1^−/− mice) are resistant to the hepatic engraftment of MC38 colon carcinoma cells, while these cells engraft normally in the mouse subcutaneous tissue. Tumor intake in the liver could be enhanced by the systemic delivery of a recombinant adenovirus encoding CT-1, which also partly rescued the resistance of CT-1^−/− mice to the hepatic engraftment of MC38 cells. Moreover, systemic treatment of wild-type (WT) mice with a novel antibody-neutralizing mouse CT-1 also reduced engraftment of this model. Conversely, experiments with Panc02 pancreatic cancer and B16-OVA melanoma cells in CT-1^−/− mice revealed rates of hepatic engraftment similar to those observed in WT mice. The mechanism whereby CT-1 renders the liver permissive for MC38 metastasis involves T lymphocytes and natural killer (NK) cells, as shown by selective depletion experiments and in genetically deficient mice. However, no obvious changes in the number or cell killing capacity of liver lymphocytes in CT-1^−/− animals could be substantiated. These findings demonstrate that the seed and soil concept to understand metastasis can be locally influenced by cytokines as well as by the cellular immune system.

Liver segmentation and metastases detection in MR images using convolutional neural networks

Primary tumors have a high likelihood of developing metastases in the liver, and early detection of these metastases is crucial for patient outcome. We propose a method based on convolutional neural networks to detect liver metastases. First, the liver is automatically segmented using the six phases of abdominal dynamic contrast-enhanced (DCE) MR images. Next, DCE-MR and diffusion weighted MR images are used for metastases detection within the liver mask. The liver segmentations have a median Dice similarity coefficient of 0.95 compared with manual annotations. The metastases detection method has a sensitivity of 99.8% with a median of two false positives per image. The combination of the two MR sequences in a dual pathway network is proven valuable for the detection of liver metastases. In conclusion, a high quality liver segmentation can be obtained in which we can successfully detect liver metastases.

Microsatellite instability and manifestations of angiogenesis in stage IV of sporadic colorectal carcinoma

Angiogenesis represents one of the critical mechanisms that facilitates carcinoma development. The study objective was to evaluate whether the microsatellite instability of colorectal carcinoma has impact on the angiogenesis activity in liver metastases.In a cohort of 80 randomly selected patients with stage IV colorectal carcinoma, 30% were recognized as microsatellite unstable (Microsatellite instability high-frequency (MSI-H)). The endothelial progenitor cell fraction (CD309+) was counted within the subpopulation of CD34+CD45+ cell and CD34+CD45- cells by flow cytometer. vascular endothelial growth factor (VEGF) factor levels were quantified in serum samples by enzyme-linked immunosorbent assay (ELISA). A control group consisted of 36 healthy volunteers. The relationship of genomic instability to angiogenesis activity was evaluated by multivariate analysis in comparison to the controls, adopting a P < .05 value as statistically significant.The expression of endothelial progenitor cells (EPCs) and VEGF was significantly higher in MSI-H compared to both microsatellite stability (MSS) patients and healthy controls (P < .008). Multi-parametric analysis showed microsatellite instability (OR=9.12, P < .01), metastases in both lobes (OR = 32.83, P < .001) and simultaneous metastases outside liver (OR = 8.32, P < .01), as independent factors associated with increased angiogenesis as assessed by measures of EPC and VEGF. A higher percentage of EPCs within the white blood cell fraction (total % EPCs / white blood cells (WBC)) and higher serum concentrations of VEGF were present in patients with MSI-H colorectal cancer, and not with MSS cancers (P < .001).MSI-H patients with colorectal cancer metastases are associated with the overexpression of circulating EPCs and VEGF, potentially driving angiogenesis. This should be considered in therapeutic decision-making.

A new nomogram for estimating survival in patients with brain metastases secondary to colorectal cancer

BACKGROUND

The prognosis of brain metastases (BM) in colorectal cancer (CRC) is extremely poor, but the incidence is increasing. The performance of existing prognostic classifications such as recursive partitioning analysis (RPA) and graded prognostic assessment (GPA) has never been evaluated in this specific setting. Moreover, the development of nomograms for estimating survival in such patients could be extremely helpful for treating physicians.

PATIENTS AND METHODS

Between 2000 and 2013, data from 227 patients with BM from CRC were collected at 8 Italian institutions. Overall survival (OS) was estimated with the Kaplan-Meier method and statistical comparison between curves was performed using the log-rank test. The discriminative ability for OS of RPA and GPA was assessed by the Harrell C-index from univariable Cox models. Putative prognostic factors for OS were also studied by multivariable Cox analysis, using the Harrell C index to evaluate the model discriminative ability. After a backward variable selection, a nomogram was developed to predict median survival time from individual patient- and tumor-related characteristics. The nomogram was externally validated on an independent series.

RESULTS

After a median follow-up of 59 months, fifty percent of patients were still at risk at 5 months. The C index was 0.594 and 0.607 for the RPA and GPA classifications, respectively. The C-index associated with the final multivariable Cox model used for developing the nomogram was 0.643; the favorable prognostic factors for survival were lower age (p=0.061), better Karnofsky performance status (p<0.001), supratentorial site of BM (p<0.001), and lower number of BM (p=0.035). The C index evaluated on the validation series was 0.733, even better than in the development series; also, the calibration of nomogram predictions was good.

CONCLUSION

The C-index associated to the nomogram model was slightly higher than that obtained for the RPA and GPA classifications. Most importantly, the very satisfactory results of nomogram validation on the external series, make us confident that our instrument may assist in prognostic assessment, treatment decision making, and enrollment into clinical trials.

Vascular endothelial growth factor accelerates establishment of a model of hepatic metastasis in Walker-256 tumor-bearing rats

BACKGROUND

Animal models of secondary liver cancer are limited by the time required for the development of hepatic metastases. The authors administered vascular endothelial growth factor (VEGF) to stimulate tumor growth in a model of hepatic metastasis.

METHODS

A 0.5 to 1.0 mm³ Walker-256 carcinosarcoma tumor tissue was implanted into the livers of 45 Sprague-Dawley rats, randomly assigned to 3 equal groups to receive daily injections (0.1 mL), for 1 week, of either normal saline (control group), 20 mg/L VEGF (VEGF-20 group) or 40 mg/L VEGF (VEGF-40 group). Tumor growth was assessed by magnetic resonance imaging after 3, 7 and 14 days, and overall survival was recorded.

RESULTS

Three days after implantation, no tumors were detected by magnetic resonance imaging in the control group. In contrast, tumors were observed in 50% of rats in the VEGF-20 group and 66.7% of rats in the VEGF-40 group (P < 0.05). By day 7, tumors were detected in 92.8% of rats in the VEGF-20 group, 86.7% of rats in the VEGF-40 group, but only 21.4% of rats in the control group (P < 0.05). Tumor size increased progressively, reaching 1.81 ± 0.08, 2.51 ± 0.12 and 2.67 ± 0.10 cm³ in the control, VEGF-20 and VEGF-40 groups, respectively, 14 days after implantation of tumor tissue. Median survival times were significantly shorter in the VEGF-40 group (15 days) than in the control and VEGF-20 groups (27 and 25, respectively) (both P < 0.05).

CONCLUSIONS

Daily VEGF injection (20 mg/L, 1 week) accelerates tumorigenesis without compromising survival, potentially extending the period in which experiments can be conducted in this model.

Imaging in resectable colorectal liver metastasis patients with or without preoperative chemotherapy: results of the PROMETEO-01 study

Background:

The aim of the PROMETEO-01 Study was to define the diagnostic accuracy of imaging techniques in colorectal cancer liver metastasis (CRCLM) patients.

Methods:

Patients referred to Bologna S. Orsola-Malpighi Hospital performed a computed-tomography scan (CT), magnetic resonance (MR), 18F-FDG-PET/CTscan (PET/CT) and liver contrast-enhanced-ultrasound (CEUS); CEUS was also performed intraoperatively (i-CEUS). Every pathological lesion was compared with imaging data.

Results:

From December 2007 to August 2010, 84 patients were enrolled. A total of 51 (60.71%) resected patients were eligible for analysis. In the lesion-by-lesion analysis 175 resected lesions were evaluated: 67(38.3%) belonged to upfront resected patients (group-A) and 108 (61.7%) to chemotherapy-pretreated patients (group-B). In all patients the sensitivity of MR proved better than CT (91% vs 82% P=0.002), CEUS (91 vs 81% P=0.008) and PET/CT (91% vs 60% P=0.000), whereas PET/CT showed the lowest sensitivity. In group-A the sensitivity of i-CEUS, MR, CT, CEUS and PET/CT was 98%, 94%, 91%, 84% and 78%, respectively. In group-B the i-CEUS proved equivalent in sensitivity to MR (95% and 90%, respectively, P=0.227) and both were significantly more sensitive than other procedures. The CT sensitivity in group-B was lower than in group-A (77% vs 91%, P=0.024).

Conclusions:

A thoraco-abdominal CT provides an adequate baseline evaluation and guides judgment as to the resectability of CRCLM patients. In the subset of candidates for induction chemotherapy to increase the chance of liver resection, the most rational approach is to add MR for the staging and restaging of CRCLM.

Defining resectability of colorectal liver metastases: how and why?

SUMMARY Treatment outcome in metastatic colorectal carcinoma has improved because of advancements in medical therapy and increased use of liver resections. In primary nonresectable disease, prognosis improves when a secondary resection is performed after successful downsizing by neoadjuvant systemic therapy. Which patient groups may profit from a secondary liver resection and which neoadjuvant systemic therapy has the optimal chance of conversion to resectability has not been defined because various patient groups were selected in different studies and there is a lack of consensus on resectability. This invalidates cross-study comparisons of resection rates and survival rates. Prospective trials in which secondary resection rate is a predefined end point are needed and will allow more insight into this topic.

Resectable liver metastases from colorectal cancer: where we are now and where do we go from here?

SUMMARY Liver metastases from colorectal cancer represent a peculiar clinical scenario in everyday practice, since treatment should achieve long-term survival or even a cure in selected patients. Presentation may vary between single cases, ranging from easily resectable lesions to more advanced metastatic spreading for which surgery can only be considered after major tumor shrinkage. For resectable liver metastases, surgery remains the essential step in the curative approach to the disease, even though different ablative procedures may be considered as valuable alternatives in certain subsets. Postoperative or perioperative chemotherapy may further improve long-term outcome, even though treatment benefits and harms related to liver toxicity should be carefully balanced in each patient. A comprehensive multidisciplinary assessment of patient- and tumor-related features remains the key to complement the clinical aspects with the biological characterization in the framework of a personalized therapeutic approach.

Assessment of advances of outcome quality in colon carcinoma at a single center

SUMMARY Background: Measuring outcome quality in colon carcinoma is important for efficient quality management. Patients & methods: Four complementary methods of survival analysis have been applied to compare the survival of patients with curatively resected colon carcinoma in two time periods: 1978–1994 (n = 979) and 1995–2005 (n = 639). Results: The 5-year survival rates of both cohorts varied widely depending on the applied analysis method with various improvements in the survival rates. The most evident progress was found in cancer-related survival of pathological stage III and IV disease. Conclusion: High-quality, complete follow-up data facilitate a complex analysis of survival. Advances in surgical technique and treatment of distant metastases, both in a multidisciplinary setting when appropriate, may be important reasons for improved survival in colon carcinoma.