Higher Tumor Burden Neutralizes Negative Margin Status in Hepatectomy for Colorectal Cancer Liver Metastasis

Chromosomal instability is associated with prognosis and efficacy of bevacizumab after resection of colorectal cancer liver metastasis

INTRODUCTION

Individualized treatment of colorectal cancer liver metastases (CRLM) remains challenging due to differences in the severity of metastatic disease and tumour biology. Exploring specific prognostic risk subgroups is urgently needed. The current study aimed to investigate the prognostic value of chromosomal instability (CIN) in patients with initially resectable CRLM and the predictive value of CIN for the efficacy of bevacizumab.

METHODS

Ninety-one consecutive patients with initially resectable CRLM who underwent curative liver resection from 2006 to 2018 at Sun Yat-sen University Cancer Center were selected for analysis. CIN was evaluated by automated digital imaging systems. Immunohistochemistry (IHC) was performed to detect interleukin-6 (IL-6), vascular endothelial growth factor A (VEGFA) and CD31 expression in paraffin-embedded specimens. Recurrence-free survival (RFS) and overall survival (OS) were analysed using the Kaplan-Meier method and Cox regression models.

RESULTS

Patients with high chromosomal instability (CIN-H) had a worse 3-year RFS rate (HR, 1.953; 95% CI, 1.001-3.810; p = 0.049) and a worse 3-year OS rate (HR, 2.449; 95% CI, 1.150-5.213; p = 0.016) than those with low chromosomal instability (CIN-L). CIN-H was identified as an independent prognostic factor for RFS (HR, 2.569; 95% CI, 1.078-6.121; p = 0.033) and OS (HR, 3.852; 95% CI, 1.173-12.645; p = 0.026) in the multivariate analysis. The protein levels of IL-6, VEGFA and CD31 were upregulated in patients in the CIN-H group compared to those in the CIN-L group in both primary tumour and liver metastases tissues. Among them, 22 patients with recurrent tumours were treated with first-line bevacizumab treatment and based on the clinical response assessment, disease control rates were adversely associated with chromosomal instability (p = 0.043).

CONCLUSIONS

Our study showed that high chromosomal instability is a negative prognostic factor for patients with initially resectable CRLM after liver resection. CIN may have positive correlations with angiogenesis through expression of IL-6-VEGFA axis and be used as a potential predictor of efficacy of bevacizumab.

Transplantation for colorectal liver metastasis

PURPOSE OF REVIEW

Liver transplantation has emerged as a possible treatment for selected patients with nonresectable colorectal liver metastasis, but controversy still exists regarding optimal selection criteria and acceptable outcomes.

RECENT FINDINGS

Univariate analysis in the largest cohorts confirms that metachronous disease, Oslo score = 0-1, metabolic tumor volume (MTV) less than 70 cm 3 , and tumor burden score less than 9 are positive predictive factors for good overall survival outcomes. Some recent trials might suggest that technical resectability is not a valid exclusion criterion for patients with high tumor load and favorable prognostic scores in the transplant evaluation. Recent developments in circulation DNA technology and liquid biopsy may play a future role in the selection and monitoring of patients.

SUMMARY

Evaluation for transplant needs multidisciplinary involvement and should not be delayed until the failure of conventional oncological therapy. Larger data sets are needed to refine the selection criteria for liver transplantation in colorectal liver metastasis (CRLM).

Impact of Surgical Margin Width on Prognosis Following Resection of Hepatocellular Carcinoma Varies on the Basis of Preoperative Alpha-Feto Protein and Tumor Burden Score

BACKGROUND

We sought to examine the prognostic impact of margin width at time of hepatocellular carcinoma (HCC) resection relative to the alpha-feto protein tumor burden score (ATS).

PATIENTS AND METHODS

Patients who underwent curative-intent hepatectomy for HCC between 2000 and 2020 were identified from a multi-institutional database. The impact of margin width on overall survival and recurrence-free survival was examined relative to ATS using univariable and multivariable analyses.

RESULTS

Among 782 patients with HCC who underwent resection, median ATS was 6.5 [interquartile range (IQR) 4.3-10.2]. Most patients underwent R0 resection (n = 613, 78.4%); among patients who had an R0 resection, 325 (41.6%) had a margin width > 5 mm while 288 (36.8%) had a 0-5 mm margin width. Among patients with high ATS, an increasing margin width was associated with incrementally better overall and recurrence-free survival. In contrast, among patients with low ATS, margin width was not associated with long-term outcomes. On multivariable Cox regression analysis, each unit increase in ATS was independently associated with a 7% higher risk of death [hazard ratio (HR) 1.07; 95% confidence interval (CI) 1.03-1.11, p < 0.001]. While the incidence of early recurrence was not associated with margin width among patients with low ATS, wider margin width was associated with an incrementally lower incidence of early recurrence among patients with high ATS.

CONCLUSION

ATS, an easy-to-use composite tumor-related metric, was able to risk stratify patients following resection of HCC relative to overall survival and recurrence-free survival. The therapeutic impact of resection margin width had a variable impact on long-term outcomes relative to ATS.

Dynamics of the prognostic nutritional index in preoperative chemotherapy in patients with colorectal liver metastases

BACKGROUND

Identifying the prognostic indicators that reflect the efficacy of preoperative chemotherapy is necessary. In this study, we investigated the prognostic indicators targeting the systemic inflammatory response for the administration of preoperative chemotherapy in patients with colorectal liver metastases.

METHODS

Data for 192 patients were retrospectively analyzed. The relationship between overall survival and clinicopathological variables, including biomarkers such as the prognostic nutritional index, was investigated in patients who underwent upfront surgery or preoperative chemotherapy.

RESULTS

In the upfront surgery group, extrahepatic lesion (p=0.01) and low prognostic nutritional index (p < 0.01) were significant prognostic indicators, whereas a decrease in the prognostic nutritional index (p=0.01) during preoperative chemotherapy were independent poor prognostic factors in the preoperative chemotherapy group. In particular, a decrease in the prognostic nutritional index was a significant prognostic marker in patients aged <75 years (p=0.04). In patients with a low prognostic nutritional index aged <75 years, preoperative chemotherapy significantly prolonged overall survival (p=0.02).

CONCLUSION

A decrease in the prognostic nutritional index during preoperative chemotherapy predicted overall survival of patients with colorectal liver metastases after hepatic resection, and preoperative chemotherapy may be effective for patients aged <75 years with a low prognostic nutritional index.

Prognostic impact of R1 resection margin in synchronous and simultaneous colorectal liver metastasis resection: a retrospective cohort study

BACKGROUND

A margin ≥ 1 mm is considered a standard resection margin for colorectal liver metastasis (CRLM). However, microscopic incomplete resection (R1) is not rare since aggressive surgical resection has been attempted in multiple and bilobar CRLM. This study aimed to investigate the prognostic impact of resection margins and perioperative chemotherapy in patients with CRLM.

METHODS

A total of 368 of 371 patients who underwent simultaneous colorectal and liver resection for synchronous CRLM between 2006 and June 2017, excluding three R2 resections, were included in this study. R1 resection was defined as either abutting tumor on the resection line or involved margin in the pathological report. The patients were divided into R0 (n = 304) and R1 (n = 64) groups. The clinicopathological characteristics, overall survival, and intrahepatic recurrence-free survival were compared between the two groups using propensity score matching.

RESULTS

The R1 group had more patients with ≥ 4 liver lesions (27.3 vs. 50.0%, P < 0.001), higher mean tumor burden score (4.4 vs. 5.8%, P = 0.003), and more bilobar disease (38.8 vs. 67.2%, P < 0.001) than the R0 group. Both R0 and R1 groups showed similar long-term outcomes in the total cohort (OS, P = 0.149; RFS, P = 0.414) and after matching (OS, P = 0.097, RFS: P = 0.924). However, the marginal recurrence rate was higher in the R1 group than in the R0 group (26.6 vs. 16.1%, P = 0.048). Furthermore, the resection margin did not have a significant impact on OS and RFS, regardless of preoperative chemotherapy. Poorly differentiated, N-positive stage colorectal cancer, liver lesion number ≥ 4, and size ≥ 5 cm were poor prognostic factors, and adjuvant chemotherapy had a positive impact on survival.

CONCLUSIONS

The R1 group was associated with aggressive tumor characteristics; however, no effect on the OS and intrahepatic RFS with or without preoperative chemotherapy was observed in this study. Tumor biological characteristics, rather than resection margin status, determine long-term prognosis. Therefore, aggressive surgical resection should be considered in patients with CRLM expected to undergo R1 resection in this multidisciplinary approach era.

Development and Validation of an α-Fetoprotein Tumor Burden Score Model to Predict Postrecurrence Survival among Patients with Hepatocellular Carcinoma

BACKGROUND

The purpose of this study is to establish a prognostic model to predict postrecurrence survival (PRS) probability after initial resection of hepatocellular carcinoma (HCC).

STUDY DESIGN

Patients with recurrent HCC after curative resection were identified through a multicenter consortium (training cohort, TC); data were from a separate institution were used as validation cohort (VC). The α-fetoprotein (AFP) tumor burden score (ATS) was defined as the distance from the origin on a 3-dimensional Cartesian coordinate system that incorporated 3 variables: largest tumor diameter ( x axis), number of tumors ( y axis), and ln AFP ( z axis). ATS was calculated using the Pythagorean theorem: ATS 2 = (largest tumor diameter) 2 + (number of tumors) 2 + (ln AFP) 2 , where ATS d and ATS r represent ATS at the time of initial diagnosis and at the time of recurrence, respectively. The final model was ATS m = ATS d + 4 × ATS r . Predictive performance and discrimination of the ATS model were evaluated and compared with traditional staging systems.

RESULTS

The ATS model demonstrated strong predictive performance of PRS in both the TC (area under the curve [AUC] 0.70) and VC (AUC 0.71). An ATS-based nomogram was able to stratify patients accurately into low- and high-risk categories relative to PRS (TC: ATS m ≤ 27, 74.9 months vs. ATS m ≥ 28, 23.3 months; VC: ATS m ≤ 27, 59.4 months vs. ATS m ≥ 28, 15.1 months; both p < 0.001). The ATS model predicted PRS among patients undergoing curative or noncurative treatment of HCC recurrence (both p < 0.05). Of note, the ATS model outperformed the Barcelona Clinic Liver Cancer (BCLC), China Liver Cancer (CNLC), and American Joint Committee on Cancer (AJCC) staging systems relative to 1-, 2-, 3-, 4- and 5-year PRS (AUC 0.70, vs. BCLC, AUC 0.50, vs. CNLC, AUC 0.54, vs. AJCC, AUC 0.51).

CONCLUSIONS

The ATS model had excellent prognostic discriminatory power to stratify patients relative to PRS.

Higher Tumor Burden Status Dictates the Impact of Surgical Margin Status on Overall Survival in Patients Undergoing Resection of Intrahepatic Cholangiocarcinoma

BACKGROUND

The present study aimed to examine the prognostic significance of margin status following hepatectomy of intrahepatic cholangiocarcinoma (ICC) relative to overall tumor burden and nodal status.

METHOD

Patients who underwent curative-intent surgery for ICC between 1990 and 2017 were included from a multi-institutional database. The impact of margin status and width on overall survival (OS) was examined relative to TBS and preoperative nodal status.

RESULTS

Among 1105 patients with ICC who underwent resection, median tumor burden score (TBS) was 6.1 (IQR 4.2-8.8) and 218 (19.7%) patients had N1 disease. More than one in eight patients had an R1 surgical margin (n = 154, 13.9%). Among patients with low or medium TBS, an increasing margin width was associated with an incrementally improved 5-year OS (R1 31.9% vs. 1-3 mm 38.5% vs. 3-10 mm 48.0% vs. ≥ 10 mm 52.3%). In contrast, among patients with a high TBS, margin width was not associated with better survival (R1 28.9% vs. 1-3 mm 22.8% vs. 3-10 mm 29.6% vs. ≥ 10 mm 13.7%). In addition, surgical margin status did not impact survival with cutoffs of TBS 7 or greater. Furthermore, patients with low or medium TBS and preoperative negative lymph nodes derived a survival benefit from an R0 resection (R1 resection, HR 2.15, 95% CI 1.35-3.44, p = 0.001). In contrast, margin status was not associated with prognosis among patients with a high TBS and preoperative positive/suspicious lymph nodes (R1 resection, HR 1.34, 95% CI 0.58-3.11, p = 0.50).

CONCLUSION

R0 resection and wider margin resection resulted in improved outcomes in patients with low tumor burden; however, the survival benefit of negative margin status disappeared in patients with underlying poor tumor biology.

Label-free multiphoton microscopy enables histopathological assessment of colorectal liver metastases and supports automated classification of neoplastic tissue

As the state of resection margins is an important prognostic factor after extirpation of colorectal liver metastases, surgeons aim to obtain negative margins, sometimes elaborated by resections of the positive resection plane after intraoperative frozen sections. However, this is time consuming and results sometimes remain unclear during surgery. Label-free multimodal multiphoton microscopy (MPM) is an optical technique that retrieves morpho-chemical information avoiding all staining and that can potentially be performed in real-time. Here, we investigated colorectal liver metastases and hepatic tissue using a combination of three endogenous nonlinear signals, namely: coherent anti-Stokes Raman scattering (CARS) to visualize lipids, two-photon excited fluorescence (TPEF) to visualize cellular patterns, and second harmonic generation (SHG) to visualize collagen fibers. We acquired and analyzed over forty thousand MPM images of metastatic and normal liver tissue of 106 patients. The morphological information with biochemical specificity produced by MPM allowed discriminating normal liver from metastatic tissue and discerning the tumor borders on cryosections as well as formalin-fixed bulk tissue. Furthermore, automated tissue type classification with a correct rate close to 95% was possible using a simple approach based on discriminant analysis of texture parameters. Therefore, MPM has the potential to increase the precision of resection margins in hepatic surgery of metastases without prolonging surgical intervention.

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.

Using Artificial Intelligence to Find the Optimal Margin Width in Hepatectomy for Colorectal Cancer Liver Metastases

Importance

In patients with resectable colorectal cancer liver metastases (CRLM), the choice of surgical technique and resection margin are the only variables that are under the surgeon's direct control and may influence oncologic outcomes. There is currently no consensus on the optimal margin width.

Objective

To determine the optimal margin width in CRLM by using artificial intelligence-based techniques developed by the Massachusetts Institute of Technology and to assess whether optimal margin width should be individualized based on patient characteristics.

Design, Setting, and Participants

The internal cohort of the study included patients who underwent curative-intent surgery for KRAS-variant CRLM between January 1, 2000, and December 31, 2017, at Johns Hopkins Hospital, Baltimore, Maryland, Memorial Sloan Kettering Cancer Center, New York, New York, and Charité-University of Berlin, Berlin, Germany. Patients from institutions in France, Norway, the US, Austria, Argentina, and Japan were retrospectively identified from institutional databases and formed the external cohort of the study. Data were analyzed from April 15, 2019, to November 11, 2021.

Exposures

Hepatectomy.

Main Outcomes and Measures

Patients with KRAS-variant CRLM who underwent surgery between 2000 and 2017 at 3 tertiary centers formed the internal cohort (training and testing). In the training cohort, an artificial intelligence-based technique called optimal policy trees (OPTs) was used by building on random forest (RF) predictive models to infer the margin width associated with the maximal decrease in death probability for a given patient (ie, optimal margin width). The RF component was validated by calculating its area under the curve (AUC) in the testing cohort, whereas the OPT component was validated by a game theory-based approach called Shapley additive explanations (SHAP). Patients from international institutions formed an external validation cohort, and a new RF model was trained to externally validate the OPT-based optimal margin values.

Results

This cohort study included a total of 1843 patients (internal cohort, 965; external cohort, 878). The internal cohort included 386 patients (median [IQR] age, 58.3 [49.0-68.7] years; 200 men [51.8%]) with KRAS-variant tumors. The AUC of the RF counterfactual model was 0.76 in both the internal training and testing cohorts, which is the highest ever reported. The recommended optimal margin widths for patient subgroups A, B, C, and D were 6, 7, 12, and 7 mm, respectively. The SHAP analysis largely confirmed this by suggesting 6 to 7 mm for subgroup A, 7 mm for subgroup B, 7 to 8 mm for subgroup C, and 7 mm for subgroup D. The external cohort included 375 patients (median [IQR] age, 61.0 [53.0-70.0] years; 218 men [58.1%]) with KRAS-variant tumors. The new RF model had an AUC of 0.78, which allowed for a reliable external validation of the OPT-based optimal margin. The external validation was successful as it confirmed the association of the optimal margin width of 7 mm with a considerable prolongation of survival in the external cohort.

Conclusions and Relevance

This cohort study used artificial intelligence-based methodologies to provide a possible resolution to the long-standing debate on optimal margin width in CRLM.

Application of Tumor Burden Score for predicting conversion outcome in patients with initially unresectable colorectal liver metastases after first-line systemic therapy

BACKGROUND

Patients with initially unresectable colorectal liver metastases (CRLM) could achieve survival benefit from successful conversion therapy. Recently, Tumor Burden Score (TBS) was proposed as a valuable index to predict outcome following resection of CRLM. The study is aimed to investigate the association of TBS with conversion outcome.

METHODS

A total of 234 patients who underwent first-line treatment in our center were enrolled as training cohort. The validation cohort was developed from 89 patients in our previous study. Cut-off value of TBS was calculated to stratify patients into two groups. Significance test and logistic regression model were used to examine the prediction value of TBS for conversion outcome after first-line systemic therapy. Kaplan-Meier method and Cox proportional hazard model were applied to assess the prognostic value of TBS.

RESULTS

TBS showed good discriminatory power [area under curve (AUC) 0.726, p < 0.001] with cut-off value defined as 14.3 in training cohort, which was validated in the validation cohort. Increasing TBS was related to adverse chemotherapy response and conversion outcome. Low TBS group had three times higher conversion rate than that in high TBS group (57.3% versus 19.0%, p < 0.001). Multivariate analysis indicated that high TBS [odds ratio (OR) = 3.676, 95% confidence interval (CI) 1.671-8.429, p = 0.002], first-line treatment response as stable disease (SD) or progressive disease (PD) (OR = 9.247; 95% CI 4.736-18.846, p < 0.001), and absence of targeted therapy (OR = 2.453, 95% CI 1.139-5.455, p = 0.024) were three independent risk factors for failure conversion outcome. High TBS was significantly associated with conversion outcome whatever chemotherapy response, addition of targeted therapy, and Kirsten rat sarcoma viral oncogene homolog (KRAS) status. High TBS was also associated with worse overall survival.

CONCLUSION

TBS should be applied in clinical practice to predict conversion outcome in patients with initially unresectable CRLM.

Prognostic value of a novel biomarker combining DNA ploidy and tumor burden score for initially resectable liver metastases from patients with colorectal cancer

Background

Colorectal cancer liver metastases (CRLM) has not been identified as a unified disease entity due to the differences in the severity of metastatic disease and tumor aggressiveness. A screen for specific prognostic risk subgroups is urgently needed. The current study aimed to investigate the prognostic value of DNA ploidy, stroma fraction and nucleotyping of initially resectable liver metastases from patients with CRLM.

Methods

One hundred thirty-nine consecutive patients with initially resectable CRLM who underwent curative liver resection from 2006 to 2018 at Sun Yat-sen University Cancer Center were selected for analysis. DNA ploidy, stroma fraction and nucleotyping of liver metastases were evaluated using automated digital imaging systems. Recurrence-free survival (RFS) and overall survival (OS) were analyzed using the Kaplan-Meier method and Cox regression models.

Results

DNA ploidy was identified as an independent prognostic factor for RFS (HR, 2.082; 95% CI 1.053–4.115; P = 0.035) in the multivariate analysis, while stroma-tumor fraction and nucleotyping were not significant prognostic factors. A significant difference in 3-year RFS was observed among the low-, moderate- and high-risk groups stratified by a novel parameter combined with the tumor burden score (TBS) and DNA ploidy (72.5% vs. 63.2% vs. 37.3%, P = 0.007). The high-risk group who received adjuvant chemotherapy had a significantly better 3-year RFS rate than those without adjuvant chemotherapy (46.7% vs. 24.8%; P = 0.034).

Conclusions

Our study showed that DNA ploidy of liver metastases is an independent prognostic factor for patients with initially resectable CRLM after liver resection. The combination of DNA ploidy and TBS may help to stratify patients into different recurrence risk groups and may guide postoperative treatment among the patients.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12935-021-02250-x.

Liver transplantation versus liver resection for colorectal liver metastasis: a survival benefit analysis in patients stratified according to tumor burden score

Liver transplantation (LT) for colorectal liver metastasis (CRLM) may provide excellent survival rates in patients with unresectable disease. High tumor load is a risk factor for recurrence and low overall survival (OS) after liver resection (LR). We tested the hypothesis that LT could offer better survival than LR in patients with high tumor load. LR performed at Padua University Hospital for CRLM was compared with LT for unresectable CRLM performed both at Oslo and Padua. High tumor load was defined as tumor burden score (TBS) ≥ 9, and inclusion criteria were as in the SECA-I transplant study. 184 patients were eligible: 128 LRs and 56 LTs. 5-year OS after LR and LT was 40.5% and 54.7% (P = 0.102). In the high TBS cohort, 5-year OS after LR and LT was 22.7% and 52.2% (P = 0.055). In patients with Oslo score ≤ 2 and TBS ≥ 9 (13 LR; 24 LT) the 5-year OS after LR and LT was 14.6% and 69.1% (P = 0.002). The corresponding disease-free survival (DFS) was 0% and 22.9% (P = 0.005). Selected CRLM patients with low Oslo score and high TBS could benefit from LT with survival outcomes that are far better than what is achieved by LR.

Parenchymal-sparing hepatectomy for colorectal liver metastases reduces postoperative morbidity while maintaining equivalent oncologic outcomes compared to non-parenchymal-sparing resection

BACKGROUND

Modern chemotherapy and repeat hepatectomy allow to tailor the surgical strategies for the treatment of colorectal liver metastases (CRLM). This study addresses the hypothesis that parenchymal-sparing hepatectomy reduces postoperative complications while ensuring similar oncologic outcomes compared to the standardized non-parenchymal-sparing procedures.

METHODS

Clinicopathological data of patients who underwent liver resection for CRLM between 2012 and 2019 at a hepatobiliary center in Switzerland were assessed. Patients were stratified according to the tumor burden score [TBS² = (maximum tumor diameter in cm)² + (number of lesions)²)] and were dichotomized in a lower and a higher tumor burden cohort according to the median TBS. Postoperative outcomes, overall survival (OS) and recurrence-free survival (RFS) of patients following parenchymal-sparing resection (PSR) for CRLM were compared with those of patients undergoing non-PSR.

RESULTS

During the study period, 153 patients underwent liver resection for CRLM with curative intent. PSR was performed in 79 patients with TBS <4.5, and in 42 patients with TBS ≥4.5. Perioperative chemotherapy was administered in equal rates in both groups (PSR vs. non-PSR) both in TBS ≥4.5 and TBS <4.5. In patients with lower tumor burden (TBS <4.5), PSR was associated with lower overall complication rate (15.2% vs. 46.2%, p = 0.009), a trend for lower major complication rate (8.9% vs. 23.1%, p = 0.123), and shorter length of hospital stay (5 vs. 9 days, p = 0.006) in comparison to non-PSR. For TBS <4.5, PSR resulted in equivalent 5-year OS (48% vs. 39%, p = 0.479) and equivalent 5-year RFS rates (44% vs. 29%, p = 0.184) compared to non-PSR. For TBS ≥4.5, PSR resulted in lower postoperative complication rate (33.3% vs. 63.2%, p = 0.031), a trend for lower major complication rate (23.8% vs. 42.2%, p = 0.150), lower length of hospital stay (6 vs. 9 days, p = 0.005), equivalent 5-year OS (29% vs. 22%, p = 0.314), and equivalent 5-year RFS rates (29% vs. 18%, p = 0.156) compared to non-PSR. Among all patients treated with PSR, patients undergoing minimal-invasive hepatectomy had equivalent 5-year OS (42% vs. 37%, p = 0.261) and equivalent 5-year RFS (34% vs. 34%, p = 0.613) rates compared to patients undergoing open hepatectomy.

CONCLUSIONS

PSR for CRLM is associated with lower postoperative morbidity, shorter length of hospital stay, and equivalent oncologic outcomes compared to non-PSR, independently of tumor burden. Our findings suggest that minimal-invasive PSR should be considered as the preferred method for the treatment of curatively resectable CRLM, if allowed by tumor size and location.

The prognostic impact of resection margin status varies according to the genetic and morphological evaluation (GAME) score for colorectal liver metastasis

BACKGROUND

Surgical margin status remains a controversial factor in predicting the outcome of colorectal liver metastases (CRLM) resection. Our study aims to evaluate the effects of surgical margins on oncologic outcomes with regard to the genetic and morphological evaluation (GAME) score.

METHODS

R1 resection was defined as having a less than 1 mm margin width. Patients who underwent surgery for CRLM from January 2005 to December 2018 were recruited. The patients were divided into two risk subgroups, namely, the low or medium risk (GAME 0-3) and high-risk (GAME score 4 or more) groups. The effects of margin status on overall survival (OS) and recurrence-free survival rate (RFS) were examined.

RESULTS

In total, 661 patients were recruited, among which 159 (24.1%) had R1 resection. Before hepatectomy, 514 patients showed a low or medium risk (R1 resection: n = 124), while 147 patients demonstrated a high risk (R1 resection: n = 35). In the whole cohort, multivariable analysis did show that R1 resection was associated with worse RFS and OS. While further research only found that in the low or medium risk group, R1 resection was related to poor OS and RFS. Meanwhile, in the high risk group, no significant difference was found in the median OS and RFS among patients with R0 or R1 resection.

CONCLUSION

The prognostic role of margin status varied according to the GAME score. Margin clearance only improved survival rates in patients with low or medium GAME score. In contrast, R1 resection demonstrated similar oncologic outcomes with R0 resection in patients with high GAME score.

Primary tumor resection improves prognosis of unresectable carcinomas of the transverse colon including flexures with liver metastasis: a preliminary population-based analysis

Purpose

Studies on unresectable colorectal cancer liver metastasis(CRLM) rarely analyze the prognosis of the patients from the point of colonic subsites. We aimed to evaluate the effect of primary tumor resection (PTR) and different scope of colectomy on the prognosis of patients with unresectable transverse colon cancer liver metastasis (UTCLM), hepatic flexure cancer liver metastasis (UHFLM), and splenic flexure cancer liver metastasis (USFLM).

Patients and methods

The patients were identified from the Surveillance, Epidemiology, and End Results (SEER) database from 2010 to 2015. Cox proportional hazards regression models were used to identify prognostic factors of overall survival (OS) and cause-specific survival (CSS). Kaplan-Meier analyses and log-rank tests were conducted to assess the effectiveness of PTR on survival.

Results

In total, this study included a cohort of 1960 patients: 556 cases of UHFLM, 1008 cases of UTCLM, and 396 cases of USFLM. The median survival time of whole patients was 11.0 months, ranging from 7.0 months for UHFLM patients to 15.0 months for USFLM patients. USFLM patients had the best OS and CSS, followed by UTCLM patients. UHFLM patients had the worst OS and CSS (All P < 0.001). PTR could improve the OS and CSS of UTCLM, UHFLM, and USFLM (All P < 0.001). Subgroups analysis revealed that USFLM patients with tumor size≤5 cm and negative CEA had not demonstrated an improved OS and CSS after PTR. Multivariate analysis showed that PTR and perioperative chemotherapy were common independent prognostic factors for UHFLM, UTCLM, and USFLM patients. There was no difference between segmental colon resection and larger colon resection on CSS of UHFLM, UTCLM, and USFLM patients.

Conclusions

We confirmed the different survival of patients with UTCLM, UHFLM, and USFLM, and for the first time, we proved that PTR could provide survival benefits for patients with unresectable CRLM from the perspective of colonic subsites of transverse colon, hepatic flexure, and splenic flexure. Besides, PTR may not improve the prognosis of USFLM patients with CEA- negative or tumor size≤5 cm. For oncologic outcomes, we concluded that segmental colon resection seemed an effective surgical procedure for UTCLM, UHFLM, and USFLM.

Prospective Non-Randomized Study of Intraoperative Assessment of Surgical Resection Margin of Colo-Rectal Liver Metastases

Introduction: More than 50% of patients with colorectal cancer (CRC) develop liver metastases during the natural course of disease. Surgical resection is currently the most potentially curative method in the treatment of colorectal liver metastases (CRLM). The goal of surgery is to achieve a negative resection margin (RM) of at least 1 mm, which provides the best prognosis for patients. The RM can be assessed by the pathologist of the resected liver specimen (RLS) and by the surgeon intraoperatively. The aim of this research paper is to determine the degree of agreement on intraoperative assessment of the RM by the surgeon and histopathological RM assessment by the pathologist.

Material and methods: This prospective non-randomized double-blind study was approved by the Ethics Committee of the Oncology Institute of Vojvodina and registered on ClinicalTrials.gov #NCT04634526. The study was conducted at the Oncology Institute of Vojvodina, Sremska Kamenica, Serbia. An experienced hepatobiliary surgeon assessed RM for every specimen intra-operatively, immediately after CRLM resection. Resected CRLM lesions were analyzed by two experienced pathologists. These data were compared with pathological RM assessment as a “gold standard”. RM of 1 mm or more was rated as negative RM (RM-). Disease-free survival (DFS) and recurrence rate was calculated by RM status defined by surgeon and by pathologist.

Results: From 01 January 2015 to 31 August 2019, 98 patients were enrolled in the study. There were 219 RLS with 245 CRLM. The surgeon registered positive RM (RM+) of <1mm in 41 (18.7%) RLS. Taking the result of the histopathological assessment (HPA) as the “gold standard”, it was determined that RM was true positive in 32 (14.6%) cases. False positive RM was found in 9 (4.1%) cases. False negative RM was found in 20 (9.1%) cases. True negative RM was found in 158 (72.2%) cases. Sensitivity of surgical assessment (SA) of RM+ was 61.5% (32/52). Specificity of SA of RM+ was 94.6% (158/167). The positive predictive value (PPV) was 78.0% (32/41), while the negative predictive value (NPV) was 88.8% (158/178). The overall accuracy of the RM+ SA was 86.8% (190/219). There was no statistically significant difference in the assessment of RM+ per RLS by surgeon and pathologists (p=0.061), but it was significant when analyses per patients was performed (p=0.017). Recurrence rate for RM+ patients was 48.1% (13/27, p=0.05) for SA and 35.0% (14/40, p=0.17) for HPA. Three year DFS for RM- and RM+ was 66.5% and 27.9% (p=0.04), respectively, by SA, and 64.8% and 42.1% (p=0.106), respectively, by HPA.

Conclusion: Intraoperative assessment of RM- by surgeon of RLS is clinically meaningful. There is not a statistically significant difference in the assessment of RM+ by surgeon and pathologists per RLS, but it was statically significant on a per patient basis. RM determined by surgeon has better prognostic impact on recurrence rate and 1- and 3-year DFS than standard histopathological assessment.

Impact and clinical usefulness of genetic data in the surgical management of colorectal cancer liver metastasis: a narrative review

Importance

In patients who undergo surgery for colorectal cancer liver metastases (CRLM), a number of somatic mutations have been associated with worse overall (OS) and recurrence-free survival (RFS). Although useful, an association with prognosis does not necessarily equate to an impact on surgical management.

Objective

The aim of this review was to investigate whether the best-studied somatic mutations impact surgical management of CRLM by informing: (I) post-hepatectomy surveillance; (II) selection of surgical technique; (III) selection of optimal margin width; and (IV) selection of patients for surgery. Lastly, we discuss the refinement of genetic data from overall mutation status to specific variants, as well as lesser studied somatic mutations.

Evidence Review

We conducted a computerized search using PubMed and Google Scholar for reports published so far, using mesh headings and keywords related to genetic data and CRLM.

Findings

Genetic data may impact surgical management of CRLM in three ways. Firstly, KRAS mutations can predict lung recurrences. Secondly, KRAS mutations may help tailor margin width. Thirdly, KRAS mutations may help tailor surgical technique.

Conclusions

Although genetic data may impact post-hepatectomy surveillance, selection of surgical technique and optimal margin width, their use to guide surgical selection remains elusive, as the data cannot support denying surgery to patients according to their somatic mutation profile.

Liver Transplantation for Colorectal Liver Metastasis

Purpose of Review

Accumulating evidence suggest that selected patients with nonresectable liver only metastases from colorectal cancer can be offered liver transplantation with acceptable outcome. This review provides an update on the scientific literature.

Recent Findings

The SECA-I study showed an estimated 5-year survival of 60% in a heterogenous patient population and guided the development of the first clinical selection criteria. In the sequel SECA-II trial, an estimated 5-year survival of 83% was obtained. A recent study shows that an Oslo score of 0–2, a metabolic tumor volume below 70 cm3 on PET-CT or Fong score of 0–2 at time of listing, can stratify patients with superior survival. Recurrence is common, but about 70% are slow-growing lung metastases, whereof the majority are resectable.

Summary

Liver transplantation for colorectal liver metastasis is an option in highly selected patients. Futile use of grafts can be avoided by applying stringent selection criteria.

Effect of Baseline Characteristics and Tumor Burden on Vaspin Expression and Progressive Disease in Operable Colorectal Cancer

Colorectal cancer is a highly heterogeneous malignancy in the Asian population, and it is considered an important prognostic factor for baseline characteristics, tumor burden, and tumor markers. This study investigated the effect of baseline characteristics and tumor burden on tumor marker expression and progressive disease in colorectal cancer by using partial least squares variance-based path modeling (PLS-PM). PLS-PM can be used to evaluate the complex relationship between prognostic variables and progressive disease status with a small sample of measurements and structural models. A total of 89 tissue samples of colorectal cancer were analyzed. Our results suggested that the expression of visceral adipose tissue-derived serpin (vaspin) is a potential indicator of colorectal cancer progression and may be affected by baseline characteristics such as age, sex, body mass index, and diabetes mellitus. Moreover, according to the characteristics of tumor burden, the expression of vaspin was generally higher in each progressive disease patient. The overall findings suggest that vaspin is a potential indicator of the progressive disease and may be affected by the baseline characteristics of patients.

Tumor burden score predicts tumor recurrence of non-functional pancreatic neuroendocrine tumors after curative resection

BACKGROUND

To investigate the feasibility of Tumor Burden Score (TBS) to predict tumor recurrence following curative-intent resection of non-functional pancreatic neuroendocrine tumors (NF-pNETs).

METHOD

The TBS cut-off values were determined by a statistical tool, X-tile. The influence of TBS on recurrence-free survival (RFS) was examined.

RESULTS

Among 842 NF-pNETs patients, there was an incremental worsening of RFS as the TBS increased (5-year RFS, low, medium, and high TBS: 92.0%, 73.3%, and 59.3%, respectively; P < 0.001). TBS (AUC 0.74) out-performed both maximum tumor size (AUC 0.65) and number of tumors (AUC 0.5) to predict RFS (TBS vs. maximum tumor size, p = 0.05; TBS vs. number of tumors, p < 0.01). The impact of margin (low TBS: R0 80.4% vs. R1 71.9%, p = 0.01 vs. medium TBS: R0 55.8% vs. R1 37.5%, p = 0.67 vs. high TBS: R0 31.9% vs. R1 12.0%, p = 0.11) and nodal (5-year RFS, low TBS: N0 94.9% vs. N1 68.4%, p < 0.01 vs. medium TBS: N0 81.8% vs. N1 55.4%, p < 0.01 vs. high TBS: N0 58.0% vs. N1 54.2%, p = 0.15) status on 5-year RFS outcomes disappeared among patients who had higher TBS.

CONCLUSIONS

TBS was strongly associated with risk of recurrence and outperformed both tumor size and number alone.

Retrospective cohort study of statin therapy effect on resected colorectal liver metastases

BACKGROUND

Above and beyond their role in cardiovascular risk reduction, statins appear to have a chemopreventive role in some gastro-intestinal cancers. In the quest for new chemopreventive agents, some existing established drugs such as statins have shown potential for re-purposing as chemoprevention. Probing existing drugs, whose pharmacodynamics are familiar, for novel beneficial effects offers a more cost-effective and less time-consuming strategy than establishing brand new drugs whose pharmacodynamic profile is unfamiliar. Observational studies show statins decrease the risk of developing colorectal cancer but there are no published studies exploring the potential impact of statins on carcinogenesis in colorectal liver metastases (CRLM).

AIM

To evaluate impact of statins on outcomes of CRLM resection, and secondarily to assess if statins influence CRLM histo-pathology.

METHODS

We conducted a retrospective cohort study of patients operated for CRLM over a 13-year period from 2005 to 2017. Patients were identified from a prospective database maintained in our Tertiary care hospital. All 586 patients included the study had undergone resection of CRLM following discussion at multidisclipinary team meeting, some patients requiring neoadjuvant chemotherapy to downstage CRLM prior to surgery. We analysed patient demographics, operative details, CRLM histopathology, Index of Deprivation, neutrophil-to-lymphocyte ratio, platelet-to-lymphocyte ratio and chemotherapy use in relation to clinical outcome. Statistics were performed using SPSS version 16.0; significance taken at 5%.

RESULTS

Liver resection for CRLM was undertaken in 586 patients at a median age of 68 (range 19 to 88) years. Statin therapy was used by 181 patients. Median follow-up time was 23 (range 12-96) mo and further colorectal cancer metastases developed in 267 patients. A total of 131 patients died. Multi-variate analysis identified 6 independent predictors of poorer disease-free survival: Synchronous presentation, multiple tumours, tumour size ≥ 5 cm, moderate–severe steatosis, peri-neural invasion, and R1-resection margin. Poorer overall survival was significantly associated with neo-adjuvant chemotherapy, major hepatectomy, peri-neural invasion and R1-resection margin. Neither histo-pathological nor radiological traits of CRLM were affected by statins, and, there was no demonstrable effect of statin therapy on patient outcomes.

CONCLUSION

Statin therapy does not affect patient survival following liver resection for CRLM. We postulate the reason for this key finding is that statins do not modulate tumour biology of CRLM.

KRAS Mutation Predicted More Mirometastases and Closer Resection Margins in Patients with Colorectal Cancer Liver Metastases

BACKGROUND

The presence of micrometastases is a source of recurrence after surgical resection of colorectal liver metastases (CRLM). The KRAS mutation is common in colorectal cancer, however the correlation between KRAS status and micrometastases has not been thoroughly clarified.

METHODS

We enrolled a cohort of 251 consecutive CRLM patients who received complete liver surgery with known KRAS mutation status, and collected clinicopathological information, including micrometastases, margin status, preoperative chemotherapy, and liver recurrence-free survival (LRFS) and overall survival (OS) rates.

RESULTS

KRAS-mutant (mutKRAS) patients had a higher incidence (60.3 vs. 40.8%; p = 0.002) and higher number of micrometastases [2.0 (range 0-38.0) vs. 0 (range 0-15.0); p < 0.001] than KRAS wild-type (wtKRAS) patients. The micrometastases in the mutKRAS group were more distant than those in the wtKRAS group [0.7 (range 0.1-9.0) vs. 0.6 (range 0.2-5.0) mm; p = 0.018). The mutKRAS group had more involved margin resections (21.5 vs. 9.2%; p = 0.07) and narrower margin widths [2.0 (range 0-40.0) vs. 4.3 (0-50.0) mm; p = 0.002] than the wtKRAS group. In addition, preoperative chemotherapy was associated with a lower rate of micrometastases in mutKRAS CRLM tumors (p < 0.05). mutKRAS status, positive margins, and micrometastases were all related to worse LRFS and OS (p < 0.05); however, micrometastases were not significantly correlated with OS in the multivariate analysis (p = 0.106).

CONCLUSIONS

mutKRAS patients had more micrometastases, increased R1 resections, and narrower margins. The presence of micrometastases may have led to the narrow margin width observed in these cases.

Meta-analysis of the association between primary tumour location and prognosis after surgical resection of colorectal liver metastases

BACKGROUND

Primary tumour location is emerging as an important prognostic factor in localized and metastatic colorectal cancers. However, its prognostic role in colorectal liver metastasis (CRLM) after hepatectomy remains controversial. A systematic review and meta-analysis was undertaken to evaluate its prognostic value.

METHODS

References were identified through searches of PubMed, Embase, Web of Science and the Cochrane Library comparing overall or disease-free survival after hepatic resection between patients with CRLM originating from right- or left-sided colorectal cancers. Data were pooled using hazard ratios (HRs) and 95 per cent confidence intervals according to a random-effects model. Meta-regression and subgroup analyses were conducted to assess the effect of underlying confounding factors on HR estimates and to adjust for this.

RESULTS

The final analysis included 21 953 patients from 45 study cohorts. Compared with left-sided primary tumour location, right-sided location was associated with worse overall survival (HR 1·39, 95 per cent c.i. 1·28 to 1·51; P < 0·001; prediction interval 1·00 to 1·93), and also tended to have a negative impact on disease-free survival (HR 1·18, 1·06 to 1·32; P = 0·004; prediction interval 0·79 to 1·75). Subgroup analysis showed that the negative effect of right-sided primary tumour location on overall survival was more prominent in the non-Asian population (HR 1·47, 1·33 to 1·62) than the Asian population (HR 1·18, 1·05 to 1·32) (P for interaction <0·01).

CONCLUSION

This study demonstrated a prognostic role for primary tumour location in patients with CRLM receiving hepatectomy, especially regarding overall survival. Adding primary tumour location may provide important optimization of prognosis prediction models for CRLM in current use.