Does the Site of the Primary Affect Outcomes When Ablating Colorectal Liver Metastases with Radiofrequency Ablation? Cardiovasc Intervent Radiol. 2018;41:912-919. [PMID: 29582125 DOI: 10.1007/s00270-018-1937-9]

Prognostic Effect of CEA Cut-Off in Patients with Resectable Colorectal Liver Metastases: A Meta-Analysis and Meta-Regression

BACKGROUND

Although preoperative carcinoembryonic antigen (CEA) is a variable used in most prognostic scores assessing the outcome of patients with colorectal liver metastases (CRLM) undergoing resection, it is unclear what the optimal cut-off is or in which patient subgroups CEA is most relevant. The purpose of this study is to evaluate the prognostic effect of CEA in resected CRLM patients and to explore in which subgroups CEA is most closely associated with overall survival (OS).

METHODS

A systematic literature search was performed, selecting studies that evaluated a relationship between preoperative CEA and OS in patients undergoing CRLM radical surgery. A meta-analysis assessed the overall effect size of the relationship on the selected study cohorts, based on CEA cut-off. An evaluation of 21 baseline variables was performed to explore their possible effect on the relationship between CEA and OS.

RESULTS

The study confirms a significant negative prognostic effect of increased CEA on OS (HR 1.46, CI 1.30-1.65), but heterogeneity among studies is significant. The effect is consistent for all CEA cut-offs, although the relationship tends to weaken in more recent studies for cut-offs < 10 ng/mL. Meta-regressions also suggest that the prognostic effect may be more pronounced in the elderly. In addition, the effect of CEA ≥ 20 ng/mL on OS appears significantly reduced in the subgroup with mutated RAS carcinoma.

CONCLUSIONS

For patients with resectable CRLM, the CEA cut-off should be increased to 20 ng/mL, and evaluation in prospective studies of the more pronounced negative prognostic effect of preoperative CEA in the elderly and wild-type RAS CRLM patients is recommended.

Biomarkers of Survival in Patients with Colorectal Liver Metastases Treated with Percutaneous Microwave Ablation

Background/Objectives: To evaluate the prognostic value of easily obtainable biomarkers for patients undergoing percutaneous microwave ablation (MWA) for colorectal liver metastases (CLMs). Prior studies showed that simple biomarkers, such as the lymphocyte-to-monocyte ratio (LMR), albumin-to-globulin ratio (AGR), platelet-to-lymphocyte ratio (PLR), and neutrophil-to-lymphocyte ratio (NLR), as well as cancer-specific markers, like carcinoembryonic antigen (CEA), might have a prognostic role in various malignancies; however, none of these were assessed in patients undergoing MWA for CLMs. Methods: Based on the simple laboratory results, which were determined prior to the ablation, several biomarkers, including the LMR, AGR, PLR, and NLR, were calculated. The log-rank test's optimal cutoff points for continuous variables were determined. Subsequently, univariable and multivariable Cox regression models were utilized to determine the association between various features and overall survival (OS). Results: This study included 57 CLM patients with a mean age of 63 ± 12.5 years at the time of ablation with a mean follow up of 30.9 months. The univariable model demonstrated that a high level of CEA (cutoff: 29.1 ng/mL; HR: 3.70) and a high LMR (cutoff: 5.32; HR: 4.05) were related to worse OS, whereas a high NLR (cutoff: 2.05; HR: 0.31) and primary left-sided colon cancer (HR: 0.36) were positive prognostic factors. The multivariable regression model confirmed these findings, with the exception of the LMR, which was no longer significantly associated with OS. Conclusions: This study demonstrates the feasibility of overall survival prediction and thus patient stratification based on easily obtainable biomarkers and clinicopathological features in CLM patients undergoing MWA.

Pan-Asian adapted ESMO Clinical Practice Guidelines for the diagnosis, treatment and follow-up of patients with metastatic colorectal cancer

The European Society for Medical Oncology (ESMO) Clinical Practice Guidelines for the diagnosis, treatment and follow-up of patients with metastatic colorectal cancer (mCRC), published in late 2022, were adapted in December 2022, according to previously established standard methodology, to produce the Pan-Asian adapted (PAGA) ESMO consensus guidelines for the management of Asian patients with mCRC. The adapted guidelines presented in this manuscript represent the consensus opinions reached by a panel of Asian experts in the treatment of patients with mCRC representing the oncological societies of China (CSCO), Indonesia (ISHMO), India (ISMPO), Japan (JSMO), Korea (KSMO), Malaysia (MOS), the Philippines (PSMO), Singapore (SSO), Taiwan (TOS) and Thailand (TSCO), co-ordinated by ESMO and the Japanese Society of Medical Oncology (JSMO). The voting was based on scientific evidence and was independent of the current treatment practices, drug access restrictions and reimbursement decisions in the different Asian countries. The latter are discussed separately in the manuscript. The aim is to provide guidance for the optimisation and harmonisation of the management of patients with mCRC across the different countries of Asia, drawing on the evidence provided by both Western and Asian trials, whilst respecting the differences in screening practices, molecular profiling and age and stage at presentation, coupled with a disparity in the drug approvals and reimbursement strategies, between the different countries.

Impacts of primary tumor location on outcomes in patients undergoing hepatectomy for colorectal liver metastasis vary according to tumor burden

PURPOSE

The purpose of this study was to verify whether the prognostic value of primary tumor location (PTL) for patients undergoing resection for colorectal liver metastasis (CRLM) is affected by tumor burden.

METHODS

Patients who underwent a first curative-intent surgery for CRLM from 2006 to 2017 were enrolled. The imaging tumor burden score (TBS) was calculated as TBS2 = (maximum tumor diameter in cm)2 + (number of lesions)2. Then, the prognostic role of PTL was assessed in different TBS zones.

RESULTS

The patient population consisted of 524 left-sided (LS) and 118 right-sided (RS) primary tumors. The distribution of TBS in the patient cohort was: Zone1: TBS <3 [n = 161 (25.1%)], zone 2: TBS ≥3 to <7 [n = 343 (53.4%)], and zone 3: TBS ≥7 [n = 138 (21.5%)]. In the whole cohort, the 5-year overall survival (OS) in the RS group was worse than that in the LS group (35.6% vs. 45.4%). However, after adjustment for known prognostic confounders, the RS group was not independently associated with a poorer OS (HR 1.18, p = 0.247). Among patients with TBS <7, OS in the RS group was significantly shorter than that in the LS group in both univariate and multivariate analyses. The prognostic role of PTL remained significant after propensity score matching or excluding patients who received anti-EGFR agents. Conversely, the association between PTL and OS was no longer evident in patients with TBS ≥7.

CONCLUSION

The current study demonstrates that the prognostic value of PTL varies by TBS, and RS tumors are only associated with shorter survival in patients with low or medium TBS.

The What, the Why, and the How of Liver Ablations: A Practical Guide for the Medical Oncologist

Interventional oncology plays a major role within modern oncological patient management. Image-guided thermal ablation has been recognized as a successful local therapeutic option in patients with primary and secondary malignant liver diseases, as also recalled by the recent European Society of Medical Oncology (ESMO) guidelines on colorectal metastases. As image-guided treatments may be as effective as surgery in selected patients with liver lesions, the clinical oncologist should be familiar with the indications, risks, and technical aspects of liver ablation in order to provide their patients with the best outcomes. This article provides a broad overview of the most commonly used ablation techniques and highlights the most relevant technical aspects such as the ideal setting in the operating theatre; which image-guided methods are available, including the growing application of fusion imaging; or contrast-enhanced ultrasound for guiding/monitoring the procedure. A further aim is to expand the knowledge among medical oncologists about liver ablation procedures and to provide insights into the future perspectives of percutaneous minimally invasive procedures in the liver.

Primary Tumor Sidedness, RAS and BRAF Mutations and MSI Status as Prognostic Factors in Patients with Colorectal Liver Metastases Treated with Surgery and Thermal Ablation: Results from the Amsterdam Colorectal Liver Met Registry (AmCORE)

The aim of this study was to assess primary tumor sidedness of colorectal cancer (CRC), rat sarcoma viral oncogene homolog (RAS) and v-raf murine sarcoma viral oncogene homolog B (BRAF) mutations and microsatellite instability (MSI) status as prognostic factors predicting complications, survival outcomes, and local tumor progression (LTP) following surgery and thermal ablation in patients with colorectal liver metastases (CRLM). This Amsterdam Colorectal Liver Met Registry (AmCORE) based study included 520 patients, 774 procedures, and 2101 tumors undergoing local treatment (resection and/or thermal ablation) from 2000 to 2021. Outcomes following local treatment were analyzed for primary tumor sidedness of CRC, RAS, and BRAF mutations and MSI status. The Kaplan–Meier method was used to estimate local tumor progression-free survival (LTPFS), local control (LC), distant progression-free survival (DPFS), and overall survival (OS). Uni- and multivariable analyses were performed based on Cox proportional hazards model. The chi-square test was used to analyze complications. Complications (p = 0.485), OS (p = 0.252), LTPFS (p = 0.939), and LC (p = 0.423) was not associated with tumor-sidedness. Compared to right-sided colon cancer (CC) (reference HR 1.000), DPFS was superior for left-sided CC and rectal cancer (p = 0.018) with an HR for left-sided CC of 0.742 (95% CI, 0.596–0.923) and for RC of 0.760 (95% CI, 0.597–0.966). Regarding RAS mutations, no significant difference was found in OS (p = 0.116). DPFS (p = 0.001), LTPFS (p = 0.039), and LC (p = 0.025) were significantly lower in the RAS mutation group. Though no difference in LTPFS was found between RAS wildtype and RAS mutated CRLM following resection (p = 0.532), LTPFS was worse for RAS mutated tumors compared to RAS wildtype following thermal ablation (p = 0.037). OS was significantly lower in the BRAF mutation group (p < 0.001) and in the MSI group (p < 0.001) following local treatment, while both did not affect DPFS, LTPFS, and LC. This AmCORE based study suggests the necessity of wider margins to reduce LTP rates in patients with RAS mutated CRLM, especially for thermal ablation. Upfront knowledge regarding molecular biomarkers may contribute to improved oncological outcomes.

Image-Guided Ablation for Colorectal Liver Metastasis: Principles, Current Evidence, and the Path Forward

Image-guided ablation can provide effective local tumor control in selected patients with CLM. A randomized controlled trial suggested that radiofrequency ablation combined with systemic chemotherapy resulted in a survival benefit for patients with unresectable CLM, compared to systemic chemotherapy alone. For small tumors, ablation with adequate margins can be considered as an alternative to resection. The improvement of ablation technologies can allow the treatment of tumors close to major vascular structures or bile ducts, on which the applicability of thermal ablation modalities is challenging. Several factors affect the outcomes of ablation, including but not limited to tumor size, number, location, minimal ablation margin, RAS mutation status, prior hepatectomy, and extrahepatic disease. Further understanding of the impact of tumor biology and advanced imaging guidance on overall patient outcomes might help to tailor its application, and improve outcomes of image-guided ablation.

Ten-Year Outcomes of Percutaneous Radiofrequency Ablation for Colorectal Cancer Liver Metastases in Perivascular vs. Non-Perivascular Locations: A Propensity-Score Matched Study

Purpose

To compare long-term outcomes of percutaneous radiofrequency ablation for colorectal liver metastases in perivascular versus non-perivascular locations.

Methods

This retrospective study included 388 consecutive patients with colorectal liver metastases (246 men, 142 women; age range 27–86 years) who underwent percutaneous radiofrequency ablation between January 2006 and December 2018. Propensity-score matching was performed for groups with perivascular and non-perivascular colorectal liver metastases. Rates of accumulative local tumor progression, overall survival, intra/extrahepatic recurrence, and complications were compared between the two groups.

Results

We successfully matched 104 patients each in the perivascular and non-perivascular groups (mean age: 60.1 ± 11.5 and 60.1 ± 11.3 years, respectively). Cumulative local tumor progression rates at 6 months, 1 years, 3 years, and 5 years, respectively, were 8.8%,14.8%, 18.9%, and 18.9% in the perivascular group and 8.8%, 13.1%, 15.5%, and 15.5% in the non-perivascular group. The 1-, 3-, 5-, and 10-year overall survival rates, respectively, were 91.3%, 45.6%, 23.9%, and 18.7% in the perivascular group and 88.0%, 47.2%, 27.2%, and 22.6% in the non-perivascular group. No significant between-group differences were detected in cumulative local tumor progression (p=0.567, hazard ratio: 1.224) or overall survival (p = 0.801, hazard ratio: 1.047). The major complication rate was 1.0% (1/104, p > 0.999) in both groups. Tumor size was the only independent prognostic factor for local tumor progression (hazard ratio: 2.314; p = 0.002). On multivariate analysis for overall colorectal liver metastases, tumor diameter >3 cm, tumor location in the right colon, multiple tumors, and extrahepatic metastases before radiofrequency ablation (hazard ratios: 2.046, 1.920, 1.706, and 1.892, respectively; all p < 0.001) and intrahepatic recurrence (hazard ratio: 1.564; p = 0.002) were associated with poor overall survival.

Conclusion

Cumulative local tumor progression, overall survival, and major complications rates did not differ significantly between perivascular and non-perivascular colorectal liver metastases after percutaneous radiofrequency ablation. For perivascular colorectal liver metastases, percutaneous radiofrequency ablation is a safe and effective treatment option.

Image-Guided Thermal Ablation for Colorectal Liver Metastases

Image-guided percutaneous thermal ablation is a widely acceptable local therapy for patients with colorectal liver metastases who are noneligible for surgery or present with recurrence after hepatectomy. The increasing knowledge of factors that affect oncologic outcomes has allowed selected patients with resectable small volume colorectal liver metastases to be treated by thermal ablation with curative intent. The continuous technological evolutions in imaging and image-guidance and the wide implementation of microwave ablation that overcomes most of the limitations of radiofrequency ablation have contributed to this paradigm shift. The importance of patient selection, ablation margin evaluation, and confirmation of complete tumor ablation (A0) are discussed in this article.

Impact of primary tumour location on colorectal liver metastases: A systematic review

BACKGROUND

Colorectal cancer (CRC) is the third most common cause of cancer-related death worldwide. Despite significant advances in screening, surgical management and adjuvant therapies, average 5-year survival seldom exceeds 60% in most developed nations. Metastatic disease represents the primary cause of mortality in patients with CRC, and the liver is the most common location for distant tumour spread. Up to 25% of patients are found to have synchronous liver metastases at the time of diagnosis and a further 30%-40% will develop metachronous disease in the course of follow-up. It has been suggested that primary tumour location [right side versus left side, primary tumour location (PTL)] can influence oncological outcomes in this patient group and that this should be considered in prognostic models and therapeutic decision-making algorithms. This suggestion is not universally accepted and there have been conflicting reports in the literature to date.

AIM

To provide a comprehensive summary of the available evidence regarding the impact of PTL on oncological outcomes in patients with colorectal cancer liver metastases (CRCLM).

METHODS

MEDLINE, EMBASE and COCHRANE were searched for relevant publications using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses methodology. Data on oncological outcomes was then extracted from full text articles that met the predefined inclusion criteria.

RESULTS

A total of 41 studies were identified that met predefined inclusion criteria for this review. In 21 out of 38 studies that provided data on overall survival, a statistically significant improvement in overall survival was reported in patients with left sided primary tumours. These studies included a total of 13897 patients compared with 4306 patients in the studies that did not show a significant difference. Eight studies noted a similar trend towards improved disease-free or progression-free survival. Several authors observed distinct patterns of relapse after treatment of hepatic metastases according to PTL; for example hepatic recurrence after treatment of CRCLM appears to occur more aggressively with right-sided CRC.

CONCLUSION

Taken together, the findings of the present review indicate that PTL may have a role as an independent prognostic factor when determining treatment and disease surveillance strategies in CRC. The mechanisms responsible for this variation remain poorly understood, but are likely to relate to molecular, histological and embryological differences, as well as inherent differences in therapeutic sensitivity.

Primary tumor location and the prognosis of patients after local treatment of colorectal liver metastases: a systematic review and meta-analysis

BACKGROUND

Recently numerous studies have reported primary tumor location as a potential prognostic factor after surgery for colorectal liver metastases (CRLM). The aim of this study was to comprehensively review and analyze all the available literature on the impact of primary tumor location in patients after local treatment of CRLM.

METHODS

Studies examining the association of right- and left-sided colorectal cancer and overall survival (OS) and recurrence free survival (RFS) after local treatment (resection and/or ablation) of CRLM were identified. Random-effects models were used for both clinicopathological and outcome variables. Pooled hazard ratios (HR) with 95% confidence intervals (95% CI) were shown for both OS and RFS.

RESULTS

Ten studies (including 11 patient cohorts) were eligible for inclusion, representing 3962 patients. Right-sided tumors (i.e. proximal to the splenic flexure) were observed in 1340 patients (33.8%). Median follow-up ranged from 25 to 137 months. Patients with right-sided tumors had a significantly decreased OS (HR 1.60, 95% CI 1.30-1.98, p < 0.001) and RFS (HR 1.35, 95% CI 1.04-1.77, p = 0.03), when compared to patients with left-sided tumors.

CONCLUSION

This meta-analysis suggests that patients with right-sided primaries suffer from a worse prognosis, compared to patients with left-sided primaries in patients after local treatment of CRLM.

The primary tumor location impacts survival outcome of colorectal liver metastases after hepatic resection: A systematic review and meta-analysis

OBJECTIVE

Location of the primary tumor side has become an increasingly prognostic factor for colorectal liver metastasis. The present study was to perform a meta-analysis to investigate if primary right-sided tumor impacted on long-term survival outcome of colorectal liver metastases following local treatment.

METHOD

Eligible trials were identified from the Embase, PubMed, Web of Science and the Cochrane database that were published before October in 2018. English language trials that compared long-term survival outcome of primary left-sided tumor with right-sided tumor colorectal liver metastases following local treatment were included. Hepatic resection for colorectal liver metastases was investigated. The main study outcomes included overall survival and disease free survival of primary right-sided colorectal liver metastases following local treatment. The risk factors of largest tumor size, primary node metastases, multiple tumor and RAS mutation were also analyzed. A systematic review and meta-analysis was done using a fixed-effects model. Hazard ratio with a 95% confidence interval was used to measure the pooled effect.

RESULTS

A total of twelve studies with 6387 patients were included. For primary right-sided colorectal liver metastases patients following hepatic resection, the overall pooled HR for 5-year overall survival rate was 1.354 (95% CI: 1.238-1.482; p = 0.000; I² = 33.7%, p = 0.138). The pooled HR for 5-year disease free survival rate of primary right-sided CRLM in the included studies calculated using the fix-effects model was 1.104 (95% CI: 0.987-1.235; p = 0.084; I² = 0%, p = 0.477).

CONCLUSION

It demonstrated that primary right-sided for colorectal liver metastases location was a significantly worse prognostic factor in terms of overall survival.

The value of KRAS gene status in predicting local tumor progression of colorectal liver metastases following radiofrequency ablation

PURPOSE

We investigated the relationships between KRAS gene status and local tumor progression (LTP) of colorectal liver metastases (CLMs) after treatment with percutaneous ultrasound-guided radiofrequency ablation (RFA).

MATERIALS AND METHODS

Clinical and imaging data from 76 patients (154 lesions) with CLM who underwent percutaneous ultrasound-guided RFA and had KRAS gene test results between January 2012 and June 2016 were analyzed. The average lesion size was 2.3 ± 1.0 cm (range 0.9-5.7 cm); 38 cases (82 lesions) had wild-type KRAS, and 38 cases (72 lesions) had KRAS mutations.

RESULTS

The technique effectiveness was 98.1% (151/154), and the LTP rate was 18.2% (28/154) after RFA, which was performed between January 2012 and November 2017. The mean and median follow-up were 32.7 ± 2.5 and 32.0 ± 2.6 months (range 1-70 months), respectively. Cumulative LTP rates at 6 months and 1, 2 and 3 years post-RFA for all patients were 7.4, 14.5, 17.8 and 19.2%, respectively. The LTP rate for patients with mutant KRAS (27.8% [20/72]) was significantly higher than that in patients with wild-type KRAS (9.8% [8/82]; p = .004). The cumulative LTP rates at 6 months and 1, 2 and 3 years post-RFA were 4.0, 11.1, 11.1 and 11.1%, respectively, for patients with wild-type KRAS and 11.2, 18.4, 25.2 and 36.2%, respectively, for patient with mutant KRAS (p = .011). Univariate (p = .011) and multivariate analyses (p = .005) showed that KRAS genotype in liver metastases was predictive of LTP. Multivariate analysis also showed that ablation margin size (p< .001) and modified clinical risk score (CRS; p = .033) were independent prognostic factors for LTP.

CONCLUSIONS

KRAS gene status of liver metastatic lesions was associated with LTP rates after RFA of CLM. Ablation margin size and modified CRS were also independent prognostic factors for LTP.