Prognostic Factors after Liver Resection for Colorectal Liver Metastasis

Analysis of survival outcomes following robotic hepatectomy for malignant liver diseases

BACKGROUND

Despite increased adoption of the robotic platform for complex hepatobiliary resections for malignant disease, little is known about long-term survival outcomes. This is the first study to evaluate the postoperative outcomes, and short- and long-term survival rates after a robotic hepatectomy for five major malignant disease processes.

METHODS

A prospectively collected database of patients who underwent a robotic hepatectomy for malignant disease was reviewed. Pathologies included colorectal liver metastases (CLM), hepatocellular carcinoma (HCC), Klatskin tumor, intrahepatic cholangiocarcinoma (IHCC), and gallbladder cancer (GC). Data are presented as median (mean ​± ​standard deviation) for illustrative purposes.

RESULTS

Of the 210 consecutive patients who underwent robotic hepatectomy for malignant disease, 75 (35 ​%) had CLM, 69 (33 ​%) had HCC, 27 (13 ​%) had Klatskin tumor, 20 (10 ​%) had IHCC, and 19 (9 ​%) had GC. Patients were 66 (65 ​± ​12.4) years old with a BMI of 29 (29 ​± ​6.5) kg/m2. R0 resection was achieved in 91 ​%, and 65 ​% underwent a major hepatectomy. Postoperative major complication rate was 6 ​%, length of stay was four (5 ​± ​4.3) days, and 30-day readmission rate was 17 ​%. Survival at 1, 3, and 5-years were 93 ​%/75 ​%/72 ​% for CLM, 84 ​%/71 ​%/64 ​% for HCC, 73 ​%/55 ​%/55 ​% for Klatskin tumor, 80 ​%/69 ​%/69 ​% for IHCC, 79 ​%/65 ​%/65 ​% for GC.

CONCLUSION

This study suggests a favorable 5-year overall survival benefit with use of the robotic platform in hepatic resection for colorectal metastases, hepatocellular carcinoma, intrahepatic cholangiocarcinoma, Klatskin tumor, and gallbladder cancer. The robotic platform facilitates fine dissection in complex hepatobiliary operations, with a high rate of R0 resections and excellent perioperative clinical outcomes.

Survival analysis and identification of prognostic factors in colorectal liver metastasis after liver resection

INTRODUCTION

Liver resection is the only curative treatment for colorectal liver metastasis. The identification of predictive factors leads to personalize patient management to enhance their long-term outcomes. This population-based study aimed to characterize factors associated with, and survival impact of patients who received hepatectomy for colorectal liver metastasis.

METHODS

A retrospective cohort study of all the hepatectomies for colorectal liver metastasis performed at third-level hospital of Spain (2010-2018) was conducted. The Kaplan-Meier method was used for survival analyses. Multivariable Cox and regression models were used to determine prognostic factors associated with overall survival.

RESULTS

The 5-year overall survival and disease-free survival were 42 and 33%, respectively. Survival analysis showed that metastasis features (number, largest size, distribution, and extrahepatic disease) and postsurgical factors (transfusion, major complications, and positive margin resection), as well as non-mutated KRAS, showed a significant association with survival. Otherwise, on multivariate analysis, only 5 independent risk factors were identified: major size metastasis >4 cm, RAS mutation, positive margin resection, intraoperative transfusion, and major complications.

CONCLUSIONS

According to our findings, major size metastasis >4 cm, intraoperative transfusion, and major postoperative complications continue to be traditional prognostic factors. Meanwhile, the KRAS biomarker has a powerful impact as a survival prognostic factor.

A transcriptomic signature that predicts cancer recurrence after hepatectomy in patients with colorectal liver metastases

BACKGROUND

Cancer recurrence is an important predictor of survival outcomes in patients with colorectal cancer-associated liver metastasis (CRLM), who undergo radical hepatectomy. Therefore, identification of patients with the greatest risk of recurrence is critical for developing a precision oncology strategy that might include frequent surveillance (in low-risk patients) or a more aggressive treatment approach (in high-risk patients). We performed genome-wide expression profiling, to identify and develop a transcriptomic signature for predicting recurrence in patients with CRLM.

METHODS

We analysed a total of 383 patients with CRLM, including 63 patients from a publicly available data set (the NCBI's Gene Expression Omnibus with accession number GSE81423). and 320 patients from whom surgical specimens were collected for independent training (n = 169) and validation (n = 151) of identified biomarkers. Using Cox's proportional hazard regression analysis, we evaluated the clinical significance of the identified gene signature by comparing its performance with several key clinical factors.

RESULTS

We identified a six-gene panel that robustly categorised patients with recurrence in the discovery (area under the curve (AUC) = 0.90). We showed that the panel was a significant predictor of recurrence in the clinical training (AUC = 0.83) and validation cohorts (AUC = 0.81). By combining our panel with key clinical factors, we established a risk-stratification model that emerged as an independent predictor of recurrence (AUC = 0.85; univariate: hazard ratio (HR) = 4.34, 95% confidence interval (CI) = 2.71-6.93, P < 0.001; multivariate: HR = 3.40, 95% CI = 1.76-6.56, P < 0.001). The stratification model revealed recurrence prediction in 89% of high-risk group and non-recurrence in 62% of low-risk group.

CONCLUSIONS

We established a novel transcriptomic signature that robustly predicts recurrence, which has significant implications for the management of patients with CRLM.

Prognostic Nomogram for Liver Metastatic Colon Cancer Based on Histological Type, Tumor Differentiation, and Tumor Deposit: A TRIPOD Compliant Large-Scale Survival Study

Objective

A proportional hazard model was applied to develop a large-scale prognostic model and nomogram incorporating clinicopathological characteristics, histological type, tumor differentiation grade, and tumor deposit count to provide clinicians and patients diagnosed with colon cancer liver metastases (CLM) a more comprehensive and practical outcome measure.

Methods

Using the Transparent Reporting of multivariable prediction models for individual Prognosis or Diagnosis (TRIPOD) guidelines, this study identified 14,697 patients diagnosed with CLM from 1975 to 2017 in the Surveillance, Epidemiology, and End Results (SEER) 21 registry database. Patients were divided into a modeling group (n=9800), an internal validation group (n=4897) using computerized randomization. An independent external validation cohort (n=60) was obtained. Univariable and multivariate Cox analyses were performed to identify prognostic predictors for overall survival (OS). Subsequently, the nomogram was constructed, and the verification was undertaken by receiver operating curves (AUC) and calibration curves.

Results

Histological type, tumor differentiation grade, and tumor deposit count were independent prognostic predictors for CLM. The nomogram consisted of age, sex, primary site, T category, N category, metastasis of bone, brain or lung, surgery, and chemotherapy. The model achieved excellent prediction power on both internal (mean AUC=0.811) and external validation (mean AUC=0.727), respectively, which were significantly higher than the American Joint Committee on Cancer (AJCC) TNM system.

Conclusion

This study proposes a prognostic nomogram for predicting 1- and 2-year survival based on histopathological and population-based data of CLM patients developed using TRIPOD guidelines. Compared with the TNM stage, our nomogram has better consistency and calibration for predicting the OS of CLM patients.

A novel prognostic nomogram for colorectal cancer liver metastasis patients with recurrence after hepatectomy

PURPOSE

We aimed to construct a nomogram to predict personalized post-recurrence survival (PRS) among colorectal cancer liver metastasis (CRLM) patients with post-hepatectomy recurrence.

METHODS

Colorectal cancer liver metastasis patients who received initial hepatectomy and had subsequent recurrence between 2001 and 2019 in Sun Yat-sen University Cancer Center from China were included in the study. Patients were randomly assigned to a training cohort and a validation cohort on a ratio of 2:1. Univariable analysis was first employed to select potential predictive factors for PRS. Then, the multivariable Cox regression model was applied to recognize independent prognostic factors. According to the model, a nomogram to predict PRS was established. The nomogram's predictive capacity was further assessed utilizing concordance index (C-index) values, calibration plots, and Kaplan-Meier curves.

RESULTS

About 376 patients were finally enrolled, with a 3-year PRS rate of 37.3% and a 5-year PRS rate of 24.6%. The following five independent predictors for PRS were determined to construct the nomogram: the largest size of liver metastases at initial hepatectomy, relapse-free survival, CEA level at recurrence, recurrent sites, and treatment for recurrence. The nomogram displayed fairly good discrimination and calibration. The C-index value was 0.742 for the training cohort and 0.773 for the validation cohort. Patients were grouped into three risk groups very well by the nomogram, with 5-year PRS rates of 45.2%, 23.3%, and 9.0%, respectively (p < 0.001) in the training cohort and 36.0%, 9.2%, and 4.6%, respectively (p < 0.001) in the validation cohort.

CONCLUSION

A novel nomogram was built and validated to enable the prediction of personal PRS in CRLM patients with post-hepatectomy recurrence. The nomogram may help physicians in decision making.

Comprehensive Evaluation of Relapse Risk (CERR) Score for Colorectal Liver Metastases: Development and Validation

BACKGROUND

The calculation of the tumor burden score (TBS) is not perfect because the bilobar spread of colorectal liver metastasis (CRLM) is neglected. The identification of an ideal prognostic scoring system for CRLM remains controversial.

MATERIALS AND METHODS

Patients who underwent curative intent liver resection for CRLM from one medical center were enrolled in cohort 1 (787 patients) and cohort 2 (162 patients). Tumor relapse-free survival (RFS) was the main outcome. A Cox regression model was used to identify independent predictors of prognosis. The time-dependent area under the curve, calibration curve, and C-index were employed to validate the predictive ability of the survival model.

RESULTS

Modified TBS (mTBS) was established by a mathematical equation with parameters including CRLM size, CRLM number, and unilobar or bilobar metastasis. Five preoperative predictors of worse RFS were identified in cohort 1 and incorporated into the Comprehensive Evaluation of Relapse Risk (CERR) score: KRAS/NRAS/BRAF-mutated tumor (1 point); node-positive primary (1 point); extrahepatic disease (1 point); carcinoembryonic antigen level > 200 ng/mL or carbohydrate antigen 19-9 (CA19-9) >200 U/mL (1 point); and mTBS between 5 and 11 (1 point) or 12 and over (2 points). Patients in cohort 1 were stratified by their CERR score into risk groups: the high-risk group (CERR score 4 or more), the medium-risk group (CERR score 2-3), and the low-risk group (CERR score 0-1). Importantly, internal validation in cohort 1 and further validation in cohort 2 both showed the superior discriminatory capacity of the CERR score.

CONCLUSION

mTBS should be promoted. The CERR score is a powerful prognostic tool that can help determine optimal clinical management strategies.

IMPLICATIONS FOR PRACTICE

This work resulted in the successful modification of the tumor burden score and development of a comprehensive and practical prognostic scoring system-the Comprehensive Evaluation of Relapse Risk (CERR) score. The CERR score, with a better prognostic discriminatory ability, outperformed the Fong score. Perhaps more importantly, the CERR score is a powerful prognostic tool because it unified the most consistently reported prognostic factors. Therefore, the CERR score can assist doctors in determining optimal clinical management strategies.

FDG-PET reflects tumor viability on SUV in colorectal cancer liver metastasis

BACKGROUND

Liver resection is the most effective procedure for colorectal cancer liver metastasis (CRLM); however, early recurrence is an important problem that affects the postoperative prognoses of patients with CRLM. We previously suggested a therapeutic algorithm for CRLM using fluorodeoxyglucose-positron emission tomography (FDG-PET) and revealed the applicability of FDG-PET in predicting the prognosis after liver resection of CRLM. In this study, we assessed the correlation between FDG-PET and biological viability such as proliferation or metabolic activity.

METHODS

We retrospectively evaluated 61 patients who underwent hepatectomy for CRLM. We assessed hypoxia inducible factor-1α (HIF-1α), pyruvate kinase isozyme M2 (PKM2), glucose transporter 1 (GLUT1), and Ki-67 expression via immunohistochemistry and evaluated the correlation between standardized uptake value (SUV) and these factors.

RESULTS

High HIF-1α, PKM2, and GLUT1 expression were positively correlated with high SUV expression (P = 0.0444, 0.0296, and 0.0245, respectively). Ki-67 and SUV were also positively correlated (P = 0.00164). HIF-1α expression and PKM2 expression were significantly correlated (P = 0.0430), and PKM2 expression and GLUT1 expression were extremely significantly correlated (P < 0.0001).

CONCLUSION

SUV reflected tumor proliferation or metabolic factors in CRLM. FDG-PET could be a useful modality for assessing tumor viability and may provide useful information regarding the appropriate treatment strategy for CRLM.

Predictive factors of histological response of colorectal liver metastases after neoadjuvant chemotherapy

BACKGROUND

Colorectal cancer is the third most common cancer in men and the second most common in women worldwide. Almost a third of the patients has or will develop liver metastases. Neoadjuvant chemotherapy (NAC) has recently become nearly systematic prior to surgery of colorectal livers metastases (CRLMs). The response to NAC is evaluated by radiological imaging according to morphological criteria. More recently, the response to NAC has been evaluated based on histological criteria of the resected specimen. The most often used score is the tumor regression grade (TRG), which considers the necrosis, fibrosis, and number of viable tumor cells.

AIM

To analyze the predictive factors of the histological response, according to the TRG, on CRLM surgery performed after NAC.

METHODS

From January 2006 to December 2013, 150 patients who had underwent surgery for CRLMs after NAC were included. The patients were separated into two groups based on their histological response, according to Rubbia-Brandt TRG. Based on their TRG, each patient was either assigned to the responder (R) group (TRG 1, 2, and 3) or to the non-responder (NR) group (TRG 4 and 5). All of the histology slides were re-evaluated in a blind manner by the same specialized pathologist. Univariate and multivariate analyses were performed.

RESULTS

Seventy-four patients were classified as responders and 76 as non-responders. The postoperative mortality rate was 0.7%, with a complication rate of 38%. Multivariate analysis identified five predictive factors of histological response. Three were predictive of non-response: More than seven NAC sessions, the absence of a radiological response after NAC, and a repeat hepatectomy (P < 0.005). Two were predictive of a good response: A rectal origin of the primary tumor and a liver-first strategy (P < 0.005). The overall survival was 57% at 3 yr and 36% at 5 yr. The disease-free survival rates were 14% at 3 yr and 11% at 5 yr. The factors contributing to a poor prognosis for disease-free survival were: No histological response after NAC, largest metastasis > 3 cm, more than three preoperative metastases, R1 resection, and the use of a targeted therapy with NAC (P < 0.005).

CONCLUSION

A non-radiological response and a number of NAC sessions > 7 are the two most pertinent predictive factors of non-histological response (TRG 4 or 5).

Carcinoembryonic antigen reduction after medical treatment in patients with metastatic colorectal cancer: a systematic review and meta-analysis

PURPOSE

The introduction of new drugs and multimodal treatments for the management of patients with metastatic colorectal cancer (mCRC) has reduced the importance of time-to-event endpoints and reported the attention on the response-related endpoints. Furthermore, the prognostic role of the surgical scores before the resection of metastases has not been confirmed for multimodal treatments. The purpose of this research is to perform a meta-analysis of the studies that evaluated the relationship between carcinoembryonic antigen (CEA) response and outcome in patients with mCRC receiving systemic chemotherapy.

METHODS

A systematic review of the literature on two databases and a selection of studies that evaluated the relationship between CEA response and outcome were performed according to predefined criteria. After, three meta-analyses were carried out on the selected studies, each for each outcome variable.

RESULTS

Nineteen studies have been selected. Fourteen studies (1475 patients) have documented a close association between radiological response and CEA response (odds ratio (OR), 9.03; confidence intervals (CIs), 5.14-15.87; I² statistic (I²), 72%). Four studies have reported a longer progression-free survival for patients with a CEA response (hazard ratio (HR), 0.73; CIs, 0.64-0.83; I², 23%). Finally, 10 studies (13 study cohorts) have shown a strong relationship between CEA response and overall survival (OS) (HR, 0. 62; CIs, 0.55-0.70; I², 35%).

CONCLUSIONS

CEA response merits further investigation as a surrogate endpoint of clinical trials of first-line medical therapy of patients with mCRC, and should be studied as a prognostic factor for those patients who are candidates for multimodal treatment strategies.

Short- and long-term outcomes of laparoscopic hepatectomy for colorectal liver metastases in elderly patients

Purpose

This study aimed to evaluate the short- and long-term outcomes of laparoscopic hepatectomy (LH) for colorectal liver metastases (CRLM) in elderly patients.

Patients and methods

Between January 2009 and January 2016, LH was performed for 241 consecutive patients who were ≥60 years old and had CRLM. Based on their age at the LH, the patients were divided into an elderly group (≥70 years old, 78 patients) and a middle-aged group (60–69 years old, 163 patients). The short- and long-term outcomes were compared between the two groups.

Results

Compared to the middle-aged group, the elderly group had higher values for Charlson comorbidity index, proportion of preoperative chemotherapy, and American Society of Anesthesiologists score. No other significant differences were observed in the preoperative characteristics. The elderly group had a higher conversion rate, compared to the middle-aged group, although no significant differences were observed in the surgical procedures, surgical times, intraoperative blood losses, numbers and severities of postoperative 90-day complications, postoperative 90-day mortality rates, pathology results, and other short-term outcomes. Long-term follow-up revealed similar rates of recurrence, disease-free survival, and overall survival in the two groups. Multivariable analysis revealed that age did not independently predict overall survival or disease-free survival.

Conclusion

Similar short- and long-term outcomes were observed after LH for CRLM in elderly and middle-aged patients. Thus, advanced age is not a contraindication for LH treatment in this setting.

mRNA expression profiles of colorectal liver metastases as a novel biomarker for early recurrence after partial hepatectomy

BACKGROUND

Identification of specific risk groups for recurrence after surgery for isolated colorectal liver metastases (CRLM) remains challenging due to the heterogeneity of the disease. Classical clinicopathologic parameters have limited prognostic value. The aim of this study was to identify a gene expression signature measured in CRLM discriminating early from late recurrence after partial hepatectomy.

METHODS

CRLM from two patient groups were collected: I) with recurrent disease ≤12 months after surgery (N = 33), and II) without recurrences and disease free for ≥36 months (N = 30). The patients were clinically homogeneous; all had a low clinical risk score (0-2) and did not receive (neo-) adjuvant chemotherapy. Total RNA was hybridised to Illumina arrays, and processed for analysis. A leave-one-out cross validation (LOOCV) analysis was performed to identify a prognostic gene expression signature.

RESULTS

LOOCV yielded an 11-gene profile with prognostic value in relation to recurrent disease ≤12 months after partial hepatectomy. This signature had a sensitivity of 81.8%, with a specificity of 66.7% for predicting recurrences (≤12 months) versus no recurrences for at least 36 months after surgery (X² P < 0.0001).

CONCLUSION

The current study yielded an 11-gene signature at mRNA level in CRLM discriminating early from late or no relapse after partial hepatectomy.

The vascular cooling effect in hepatic multipolar radiofrequency ablation leads to incomplete ablation ex vivo

PURPOSE

Major limitations of conventional RFA are vascular cooling effects. However, vascular cooling effects are supposed to be less pronounced in multipolar RFA. The objective of this ex vivo study was a systematic evaluation of the vascular cooling effects in multipolar RFA.

MATERIALS AND METHODS

Multipolar RFA with three bipolar RFA applicators was performed ex vivo in porcine liver (applicator distance 20 mm, energy input 40 kJ). A saline-perfused glass tube ('vessel') was placed parallel to the applicators in order to simulate a natural liver vessel. Five applicator-to-vessel geometries were tested. A liquid-filled glass tube without perfusion was used as a dry run. Ablations were orthogonally cut to the applicators at a defined height. Cooling effects were analysed qualitatively and quantitatively along these cross sectional areas.

RESULTS

Thirty-six ablations were performed. A cooling effect could be seen in all ablations with perfused vessels compared to the dry run. While this cooling effect did not have any influence on the ablation areas (859-1072 mm(2) versus 958 mm(2) in the dry run, p > 0.05), it had a distinctive impact on ablation shape. A vascular cooling effect could be observed in all ablations with perfusion directly around the vessel independent of the applicator position compared to the dry run (p < 0.01).

CONCLUSIONS

A vascular cooling effect occurred in all multipolar RFA with simulated liver vessels ex vivo independent of the applicator-to-vessel geometry. While the cooling effect did not influence the total ablation area, it had a distinctive impact on the ablation shape.