Recurrence location after resection of colorectal liver metastases influences prognosis

The Interaction Between Epigenetic Changes, EMT, and Exosomes in Predicting Metastasis of Colorectal Cancers (CRC)

Worldwide, colorectal cancer (CRC) ranks as the third most common malignancy, and the second most deadly with nearly one million attributable deaths in 2020. Metastatic disease is present in nearly 25% of newly diagnosed CRC, and despite advances in chemotherapy, less than 20% will remain alive at 5 years. Epigenetic change plays a key role in the epithelial-to-mesenchymal transition (EMT), which is a crucial phenotype for metastasis and mainly includes DNA methylation, non-coding RNAs (ncRNAs), and N6-methyladenosine (m6A) RNA, seemingly valuable biomarkers in CRCs. For ncRNAs, there exists a “molecular sponge effect” between long non-coding RNAs (lncRNAs), circular RNAs (circRNAs), and microRNAs (miRNAs). The detection of exosomes is a novel method in CRC monitoring, especially for predicting metastasis. There is a close relationship between exosomes and EMT in CRCs. This review summarizes the close relationship between epigenetic changes and EMT in CRCs and emphasizes the crucial function of exosomes in regulating the EMT process.

The prognostic significance of a histological response to preoperative chemotherapy in patients with synchronous colorectal liver metastases

Objective: Preoperative chemotherapy (PC) for colorectal liver metastasis (CRLM) is widely used to improve prognosis, but its clinical benefit has not been fully established. This study aimed to assess the effectiveness of PC for synchronous CRLM and the correlation between the histological response to PC and survival. Summary of Background Data: We enrolled 69 patients who underwent initial hepatectomy for synchronous CRLM between 2004 and 2018 at Gifu University Hospital. Methods: We retrospectively analyzed the clinicopathological factors and outcomes of 69 patients who underwent hepatectomy after receiving PC (PC group: n = 43) or who underwent upfront hepatectomy (non-PC group: n = 26). In the PC group, the patients were divided into the Grade 1 (n = 27) and Grade 2/3 (n = 16) groups according to their histological responses to PC. Results: The median survival and 5-year overall survival (OS) rates were 80.9 months and 61.5%, respectively, in the PC group and 71.7 months and 61.5%, respectively, in the non-PC group ( P = 0.867). Regarding recurrence-free survival (RFS) and remnant liver-RFS, there were no significant differences between the two groups ( P = 0.087 and 0.291). However, in a subgroup analysis, the median 5-year OS, RFS, and remnant liver RFS were significantly longer in the Grade 2/3 than Grade 1 group ( P = 0.008, P = 0.002, and P < 0.001, respectively). Conclusions: Some patients benefit from PC, and the histological response to PC had prognostic significance for patients with synchronous CRLM.

Hepatic thermal injury promotes colorectal cancer engraftment in C57/black 6 mice

Treatment options for liver metastases (primarily colorectal cancer) are limited by high recurrence rates and persistent tumor progression. Surgical approaches to management of these metastases typically use heat energy including electrocautery, argon beam coagulation, thermal ablation of surgical margins for hemostasis, and preemptive thermal ablation to prevent bleeding or to effect tumor destruction. Based on high rates of local recurrence, these studies assess whether local effects of hepatic thermal injury (HTI) might contribute to poor outcomes by promoting a hepatic microenvironment favorable for tumor engraftment or progression due to induction of procancer cytokines and deleterious immune infiltrates at the site of thermal injury. To test this hypothesis, an immunocompetent mouse model was developed wherein HTI was combined with concomitant intrasplenic injection of cells from a well-characterized MC38 colon carcinoma cell line. In this model, HTI resulted in a significant increase in engraftment and progression of MC38 tumors at the site of thermal injury. Furthermore, there were local increases in expression of messenger ribonucleic acid (mRNA) for hypoxia-inducible factor-1α (HIF1α), arginase-1, and vascular endothelial growth factor α and activation changes in recruited macrophages at the HTI site but not in untreated liver tissue. Inhibition of HIF1α following HTI significantly reduced discreet hepatic tumor development (P = 0.03). Taken together, these findings demonstrate that HTI creates a favorable local environment that is associated with protumorigenic activation of macrophages and implantation of circulating tumors. Discrete targeting of HIF1α signaling or inhibiting macrophages offers potential strategies for improving the outcome of surgical management of hepatic metastases where HTI is used.

18F-FDG PET as novel imaging biomarker for disease progression after ablation therapy in colorectal liver metastases

Purpose

Recurrent disease following thermal ablation therapy is a frequently reported problem. Preoperative identification of patients with high risk of recurrent disease might enable individualized treatment based on patients’ risk profile. The aim of the present work was to investigate the role of metabolic parameters derived from the pre-ablation ¹⁸F-FDG PET/CT as imaging biomarkers for recurrent disease in patients with colorectal liver metastases (CLM).

Methods

Included in this retrospective study were all consecutive patients with CLM treated with percutaneous or open thermal ablation therapy who had a pre-treatment baseline ¹⁸F-FDG PET/CT available. Multivariable cox regression for survival analysis was performed using different models for the metabolic parameters (SUL_peak, SUL_mean, SUL_max, partial volume corrected SUL_mean (cSUL_mean), and total lesion glycolysis (TLG)) corrected for tumour and procedure characteristics. The study endpoints were defined as local tumour progression free survival (LTP-FS), new intrahepatic recurrence free survival (NHR-FS) and extrahepatic recurrence free survival (EHR-FS). Clinical and imaging follow-up data was used as the reference standard.

Results

Fifty-four patients with 90 lesions were selected. Univariable cox regression analysis resulted in eight models. Multivariable analysis revealed that after adjusting for lesion size and the approach of the procedure, none of the metabolic parameters were associated with LTP-FS or EHR-FS. Percutaneous approach was significantly associated with a shorter LTP-FS. It was demonstrated that lower values of SUL_peak, SUL_max, SUL_mean , and cSUL_mean are associated with a significant better NHR-FS, independent of the lesion size and number and prior chemotherapy.

Conclusion

We found no association between the metabolic parameters on pre-ablation ¹⁸F-FDG PET/CT and the LTP-FS. However, low values of the metabolic parameters were significantly associated with improved NHR-FS. The clinical implication of these findings might be the identification of high-risk patients who might benefit most from adjuvant or combined treatment strategies.

Electronic supplementary material

The online version of this article (doi:10.1007/s00259-017-3637-0) contains supplementary material, which is available to authorized users.

Patterns of progression, treatment of progressive disease and post-progression survival in the New EPOC study

BACKGROUND

The addition of cetuximab (CTX) to perioperative chemotherapy (CT) for operable colorectal liver metastases resulted in a shorter progression-free survival. Details of disease progression are described to further inform the primary study outcome.

METHODS

A total of 257 KRAS wild-type patients were randomised to CT alone or CT with CTX. Data regarding sites and treatment of progressive disease were obtained for the 109 (CT n=48, CT and CTX n=61) patients with progressive disease at the cut-off date for analysis of November 2012.

RESULTS

The liver was the most frequent site of progression (CT 67% (32/48); CT and CTX 66% (40/61)). A higher proportion of patients in the CT and group had multiple sites of progressive disease (CT 8%, 4/48; CT and CTX 23%, 14/61 P=0.04). Further treatment for progressive disease is known for 84 patients of whom 69 received further CT, most frequently irinotecan based. Twenty-two patients, 11 in each arm, received CTX as a further line agent.

CONCLUSIONS

Both the distribution of progressive disease and further treatment are as expected for such a cohort. The pattern of disease progression seen is consistent with failure of systemic micrometastatic disease control rather than failure of local disease control following liver surgery.