RAS Mutation Is Associated with Decreased Survival in Patients Undergoing Repeat Hepatectomy for Colorectal Liver Metastases

Radiomics and machine learning analysis by computed tomography and magnetic resonance imaging in colorectal liver metastases prognostic assessment

OBJECTIVE

The aim of this study was the evaluation radiomics analysis efficacy performed using computed tomography (CT) and magnetic resonance imaging in the prediction of colorectal liver metastases patterns linked to patient prognosis: tumor growth front; grade; tumor budding; mucinous type. Moreover, the prediction of liver recurrence was also evaluated.

METHODS

The retrospective study included an internal and validation dataset; the first was composed by 119 liver metastases from 49 patients while the second consisted to 28 patients with single lesion. Radiomic features were extracted using PyRadiomics. Univariate and multivariate approaches including machine learning algorithms were employed.

RESULTS

The best predictor to identify tumor growth was the Wavelet_HLH_glcm_MaximumProbability with an accuracy of 84% and to detect recurrence the best predictor was wavelet_HLH_ngtdm_Complexity with an accuracy of 90%, both extracted by T1-weigthed arterial phase sequence. The best predictor to detect tumor budding was the wavelet_LLH_glcm_Imc1 with an accuracy of 88% and to identify mucinous type was wavelet_LLH_glcm_JointEntropy with an accuracy of 92%, both calculated on T2-weigthed sequence. An increase statistically significant of accuracy (90%) was obtained using a linear weighted combination of 15 predictors extracted by T2-weigthed images to detect tumor front growth. An increase statistically significant of accuracy at 93% was obtained using a linear weighted combination of 11 predictors by the T1-weigthed arterial phase sequence to classify tumor budding. An increase statistically significant of accuracy at 97% was obtained using a linear weighted combination of 16 predictors extracted on CT to detect recurrence. An increase statistically significant of accuracy was obtained in the tumor budding identification considering a K-nearest neighbors and the 11 significant features extracted T1-weigthed arterial phase sequence.

CONCLUSIONS

The results confirmed the Radiomics capacity to recognize clinical and histopathological prognostic features that should influence the choice of treatments in colorectal liver metastases patients to obtain a more personalized therapy.

Demystifying BRAF Mutation Status in Colorectal Liver Metastases : A Multi-institutional, Collaborative Approach to 6 Open Clinical Questions

OBJECTIVE

To investigate the clinical implications of BRAF -mutated (mut BRAF ) colorectal liver metastases (CRLMs).

BACKGROUND

The clinical implications of mut BRAF status in CRLMs are largely unknown.

METHODS

Patients undergoing resection for mut BRAF CRLM were identified from prospectively maintained registries of the collaborating institutions. Overall survival (OS) and recurrence-free survival (RFS) were compared among patients with V600E versus non-V600E mutations, KRAS/BRAF comutation versus mut BRAF alone, microsatellite stability status (Microsatellite Stable (MSS) vs instable (MSI-high)), upfront resectable versus converted tumors, extrahepatic versus liver-limited disease, and intrahepatic recurrence treated with repeat hepatectomy versus nonoperative management.

RESULTS

A total of 240 patients harboring BRAF -mutated tumors were included. BRAF V600E mutation was associated with shorter OS (30.6 vs 144 mo, P =0.004), but not RFS compared with non-V600E mutations. KRAS/BRAF comutation did not affect outcomes. MSS tumors were associated with shorter RFS (9.1 vs 26 mo, P <0.001) but not OS (33.5 vs 41 mo, P =0.3) compared with MSI-high tumors, whereas patients with resected converted disease had slightly worse RFS (8 vs 11 mo, P =0.01) and similar OS (30 vs 40 mo, P =0.4) compared with those with upfront resectable disease. Patients with extrahepatic disease had worse OS compared with those with liver-limited disease (8.8 vs 40 mo, P <0.001). Repeat hepatectomy after intrahepatic recurrence was associated with improved OS compared with nonoperative management (41 vs 18.7 mo, P =0.004). All results continued to hold true in the multivariable OS analysis.

CONCLUSIONS

Although surgery may be futile in patients with BRAF -mutated CRLM and concurrent extrahepatic disease, resection of converted disease resulted in encouraging survival in the absence of extrahepatic spread. Importantly, second hepatectomy in select patients with recurrence was associated with improved outcomes. Finally, MSI-high status identifies a better prognostic group, with regard to RFS while patients with non-V600E mutations have excellent prognosis.

The Role of Targeted Therapy in the Multi-Disciplinary Approach to Colorectal Liver Metastasis

Colorectal cancer (CRC) is the second most common cause of cancer-related mortality in the United States. Among newly diagnosed patients with CRC, 20% will present with metastatic disease and another 25% will develop metastases. The surgical resection of the primary tumor and metastatic disease sites confers the best chance at long-term survival. Unfortunately, many patients will recur after resection or present with unresectable disease. As such, metastatic CRC is commonly treated with a combination of surgery, systemic therapy, and/or liver-directed therapies. Despite best efforts, 5-year survival for unresectable metastatic CRC is only about 20%. CRC is a heterogeneous disease and the underlying genetic differences inform behavior, treatment strategy, and prognosis. Given the limitations of cytotoxic chemotherapy and the growing role of molecular profiling, research has focused on identifying and developing targeted therapies. We herein review how genetic profiling informs prognosis, crucial cell-signaling pathways that play a role in CRC carcinogenesis, and currently approved targeted therapies for metastatic CRC.

Colorectal liver metastases patients prognostic assessment: prospects and limits of radiomics and radiogenomics

In this narrative review, we reported un up-to-date on the role of radiomics to assess prognostic features, which can impact on the liver metastases patient treatment choice. In the liver metastases patients, the possibility to assess mutational status (RAS or MSI), the tumor growth pattern and the histological subtype (NOS or mucinous) allows a better treatment selection to avoid unnecessary therapies. However, today, the detection of these features require an invasive approach. Recently, radiomics analysis application has improved rapidly, with a consequent growing interest in the oncological field. Radiomics analysis allows the textural characteristics assessment, which are correlated to biological data. This approach is captivating since it should allow to extract biological data from the radiological images, without invasive approach, so that to reduce costs and time, avoiding any risk for the patients. Several studies showed the ability of Radiomics to identify mutational status, tumor growth pattern and histological type in colorectal liver metastases. Although, radiomics analysis in a non-invasive and repeatable way, however features as the poor standardization and generalization of clinical studies results limit the translation of this analysis into clinical practice. Clear limits are data-quality control, reproducibility, repeatability, generalizability of results, and issues related to model overfitting.

Colorectal Cancer Liver Metastases: Genomics and Biomarkers with Focus on Local Therapies

Molecular cancer biomarkers help personalize treatment, predict oncologic outcomes, and identify patients who can benefit from specific targeted therapies. Colorectal cancer (CRC) is the third-most common cancer, with the liver being the most frequent visceral metastatic site. KRAS, NRAS, BRAF V600E Mutations, DNA Mismatch Repair Deficiency/Microsatellite Instability Status, HER2 Amplification, and NTRK Fusions are NCCN approved and actionable molecular biomarkers for colorectal cancer. Additional biomarkers are also described and can be helpful in different image-guided hepatic directed therapies specifically for CRLM. For example, tumors maintaining the Ki-67 proliferation marker after thermal ablation was shown to be particularly resilient to ablation. Ablation margin was also shown to be an important factor in predicting local recurrence, with a ≥10 mm minimal ablation margin being required to attain local tumor control, especially for patients with mutant KRAS CRLM.

Genomic Predictors of Recurrence Patterns After Complete Resection of Colorectal Liver Metastases and Adjuvant Hepatic Artery Infusion Chemotherapy

BACKGROUND

Despite curative hepatectomy, most colorectal liver metastasis (CRLM) patients relapse locally within 2 years. Genomic predictors for hepatic recurrence are poorly understood. This study was designed to identify genomic signatures for recurrence in resected CRLM patients treated with adjuvant hepatic artery infusion (HAI) and/or systemic (SYS) chemotherapy.

METHODS

Patients undergoing curative hepatectomy and adjuvant HAI+SYS or SYS between January 2000 and October 2017 with next-generation sequencing data were catalogued. Gene and signaling-level alterations were checked for association with time to any (AR), liver (LR), and extrahepatic recurrence (ER) by using Kaplan-Meier analysis.

RESULTS

Of 172 receiving HAI+SYS, 100 patients recurred, with 69 LR and 83 ER. Five- and ten-year LR-free rates were 57% (95% confidence interval [CI] 48-65%) and 51% (95% CI 41-60%), respectively. Five- and 10-year ER-free, rates were 51% (95% CI 43-58%) and 45% (95% CI 36-54%), respectively. More ER was observed with tumors harboring altered KRAS (38% [95% CI 25-50%] vs. 63% [95% CI 53-71%], p-adj = 0.003) and RAS/RAF (36% [95% CI 25-48%] vs. 66% [95% CI 56-74%], p-adj < 0.001) than wild-type. Co-altered RAS/RAF-TP53 was associated with worse AR (26% [95% CI 14-40%] vs. 48% [95% CI 39-57%], p-unadj < 0.001), ER (30% [95% CI 17-45%] vs. 62% [95% CI 53-70%], p-unadj < 0.001), and LR rate (40% [95% CI 24-57%] vs. 70% [95% CI 60-77%], p-unadj = 0.002). On multivariable analysis, controlling for clinical risk score, ablation, margin status, and primary T-stage, co-altered RAS/RAF-TP53 was associated with increased risk for AR (HR = 2.14, 95% CI 1.38-3.31, p-unadj < 0.001), LR (HR = 1.79, 95% CI 1.06-3.02, p-unadj = 0.029), and ER (HR = 2.81, 95% CI 1.78-4.44, p-unadj < 0.001).

CONCLUSIONS

Altered KRAS, RAS/RAF, and RAS/RAF-TP53 associated with earlier local and distant recurrence in resected CRLM patients receiving adjuvant HAI+SYS. Co-altered RAS/RAF-TP53 was a novel predictor of LR warranting investigation of whether genomic cooperativity is associated with this relapsing phenotype. Systemic therapies tailored to high-risk tumor biology are needed to reduce distant relapse after hepatectomy.

PGC-1β and ERRα Promote Glutamine Metabolism and Colorectal Cancer Survival via Transcriptional Upregulation of PCK2

BACKGROUND

Previous studies have shown that Peroxisome Proliferator-Activated Receptor Gamma, Coactivator 1 Beta (PGC-1β) and Estrogen-Related Receptor Alpha (ERRα) are over-expressed in colorectal cancer and promote tumor survival.

METHODS

In this study, we use immunoprecipitation of epitope tagged endogenous PGC-1β and inducible PGC-1β mutants to show that amino acid motif LRELL on PGC-1β is responsible for the physical interaction with ERRα and promotes ERRα mRNA and protein expression. We use RNAsequencing to determine the genes regulated by both PGC-1β & ERRα and find that mitochondrial Phosphoenolpyruvate Carboxykinase 2 (PCK2) is the gene that decreased most significantly after depletion of both genes.

RESULTS

Depletion of PCK2 in colorectal cancer cells was sufficient to reduce anchorage-independent growth and inhibit glutamine utilization by the TCA cycle. Lastly, shRNA-mediated depletion of ERRα decreased anchorage-independent growth and glutamine metabolism, which could not be rescued by plasmid derived expression of PCK2.

DISCUSSION

These findings suggest that transcriptional control of PCK2 is one mechanism used by PGC-1β and ERRα to promote glutamine metabolism and colorectal cancer cell survival.

Precision surgery for colorectal liver metastases: Current knowledge and future perspectives

Precision surgery for colorectal liver metastases (CRLM) includes optimal selection of both the patient and surgery. Initial attempts of using clinical risk scores to identify patients for whom technically feasible surgery is oncologically futile failed. Since then, patient selection for single-stage hepatectomy followed three distinct approaches, all of which incorporated biomarkers. The BRAF V600E mutation, the G12V KRAS variant, and the triple mutation of RAS, TP53, and SMAD4 appear to be the most promising, but none can be used in isolation to deny surgery in otherwise resectable cases. Combining biomarkers with clinicopathologic factors that predict poor prognosis may be used to select patients for surgery, but external validation and matched analyses with medically treated counterparts are needed. Patient selection for special surgical procedures (two-stage hepatectomy [TSH], Associating Liver Partition and Portal vein Ligation for staged hepatectomy [ALPPS], and liver transplant [LT]) has been recently refined. Specifically, BRAF mutations and right-sided laterality have been proposed as separate contraindications to LT. A similar association of right-sided laterality, particularly when combined with RAS mutations, with very poor outcomes has been observed for ALPPS and has been suggested as a biologic contraindication. Data are scarce for TSH but RAS mutations may portend very poor survival following TSH completion. The selection of the best single-stage hepatectomy (optimal margin and type of resection) based on biomarkers remains debated, although there is some evidence that RAS may play a significant role. Lastly, although there are currently no criteria to select among the three special techniques based on their efficacy or appropriateness in different settings, RAS mutational status may be used to select patients for TSH, while right-sided tumor in conjunction with a RAS mutation may be a contraindication to LT and ALPPS.

Stage IV colon cancer patients without DENND2D expression benefit more from neoadjuvant chemotherapy

According to the EPOC study, chemotherapy could improve 5-year disease-free survival of stage IV colon cancer patients by 8.1%. However, more molecular biomarkers are required to identify patients who need neoadjuvant chemotherapy. DENND2D expression was evaluated by immunohistochemistry in 181 stage IV colon cancer patients. The prognosis was better for patients with DENND2D expression than patients without DENND2D expression (5-year overall survival [OS]: 42% vs. 12%, p = 0.038; 5-year disease-free survival: 20% vs. 10%, p = 0.001). Subgroup analysis of the DENND2D-negative group showed that patients treated with neoadjuvant chemotherapy achieved longer OS than patients without neoadjuvant chemotherapy (RR = 0.179; 95% CI = 0.054-0.598; p = 0.003). DENND2D suppressed CRC proliferation in vitro and in vivo. Downregulation of DENND2D also promoted metastasis to distant organs in vivo. Mechanistically, DENND2D suppressed the MAPK pathway in CRC. Colon cancer patients who were DENND2D negative always showed a worse prognosis and were more likely to benefit from neoadjuvant chemotherapy. DENND2D may be a new prognostic factor and a predictor of the need for neoadjuvant chemotherapy in stage IV colon cancer.

Neither Surgical Margin Status nor Somatic Mutation Predicts Local Recurrence After R0-intent Resection for Colorectal Liver Metastases

BACKGROUND

We evaluated the associations of surgical margin status and somatic mutations with the incidence of local recurrence (LR) and oncologic outcomes in patients undergoing R0-intent (microscopically negative margin) resection of colorectal liver metastases (CLM).

METHODS

Patients with CLM who underwent initial R0-intent resection and analysis of tumor tissue using next-generation sequencing during 2001-2018 were analyzed. Recurrences were classified as LR (at the resection margin), other intrahepatic recurrence, or extrahepatic recurrence. Predictors and survival effect of LR were evaluated using univariate and multivariate analysis.

RESULTS

Of 552 patients analyzed, 415 (75%) had R0 resection (margin width ≥ 1.0 mm), and 38 (7%) had LR. LR incidence was not affected by surgical margin width. RAS/TP53 co-mutation was associated with increased risk of intrahepatic recurrence (67% vs. 49%; p < 0.001) and overall recurrence (p < 0.001). However, incidence of LR did not differ significantly by RAS/TP53, BRAF, SMAD4, or FBXW7 mutation. Extrahepatic disease (hazard ratio [HR], 1.47; p = 0.034), > 8 cycles of preoperative chemotherapy (HR, 1.98; p = 0.033), tumor viability ≥ 50% (HR, 1.55; p = 0.007), RAS/TP53 co-mutation (HR, 1.69; p = 0.001), and SMAD4 mutation (HR, 2.44; p < 0.001) were independently associated with poor overall survival, but surgical margin status was not.

CONCLUSIONS

Although somatic mutations were associated with overall recurrence, neither surgical margin width nor somatic mutations affected LR risk after R0-intent hepatectomy for CLM. LR and prognosis were likely driven by individual tumor biology rather than surgical margins.

Prognostic and Therapeutic Implications of Tumor Biology in Colorectal Liver Metastases

Prognostic models allow clinicians to predict survival outcomes, facilitate patient-physician discussions, and identify subgroups with potentially distinct prognoses [...].

Emerging strategies to target RAS signaling in human cancer therapy

RAS mutations (HRAS, NRAS, and KRAS) are among the most common oncogenes, and around 19% of patients with cancer harbor RAS mutations. Cells harboring RAS mutations tend to undergo malignant transformation and exhibit malignant phenotypes. The mutational status of RAS correlates with the clinicopathological features of patients, such as mucinous type and poor differentiation, as well as response to anti-EGFR therapies in certain types of human cancers. Although RAS protein had been considered as a potential target for tumors with RAS mutations, it was once referred to as a undruggable target due to the consecutive failure in the discovery of RAS protein inhibitors. However, recent studies on the structure, signaling, and function of RAS have shed light on the development of RAS-targeting drugs, especially with the approval of Lumakras (sotorasib, AMG510) in treatment of KRASG12C-mutant NSCLC patients. Therefore, here we fully review RAS mutations in human cancer and especially focus on emerging strategies that have been recently developed for RAS-targeting therapy.

Prognostic and Therapeutic Implications of Tumor Biology, Including Gene Alterations, in Colorectal Liver Metastases

BACKGROUND

For patients with colorectal liver metastases (CLM), the combination of surgical resection with other therapeutic options is essential. This article shows how recent advances in knowledge of tumor biology, including genetic alterations, affect the choice of therapeutic approach for patients with CLM.

METHODS

We reviewed the literature on recent advances in knowledge about CLM tumor biology including genetic profiles, clinical risk score models for CLM, preoperative therapy for CLM, and liver-directed therapy for CLM.

RESULTS

Studies showed that RAS alteration is a negative prognostic factor in addition to traditional clinical risk factors (e.g., larger diameter and higher number of CLM, spread of the primary tumor to regional lymph nodes). Although the response to preoperative chemotherapy is an important predictor of survival, poor response is not a contraindication to surgical resection. The combination of surgical therapy and percutaneous ablation can be considered in marginally resectable cases; however, a wider ablation margin is required for RAS-mutant CLM. More recently, genetic analysis using next-generation sequencing showed the negative prognostic impact of alterations in TP53, SMAD4, FBXW7, and RAS/BRAF in patients with CLM. In RAS-mutant CLM, intensive follow-up is required in patients who remain recurrence free 2 years after surgery.

DISCUSSION

In patients with CLM, RAS mutation status is important in predicting postoperative survival, selecting the treatment approach, and tailoring postoperative follow-up. In addition, more recent genetic analyses of CLM have identified additional predictors of survival.

APC and PIK3CA Mutational Cooperativity Predicts Pathologic Response and Survival in Patients Undergoing Resection for Colorectal Liver Metastases

OBJECTIVE

The aim of the study was to determine the prognostic impact of co-existence of APC and PIK3CA mutations in patients undergoing preoperative chemotherapy and resection for colorectal liver metastases (CLM).

BACKGROUND

Co-occurring genetic events have been shown to drive carcinogenesis in multiple malignancies.

METHODS

We identified 396 patients with primary colorectal cancer and known somatic mutation status by next-generation sequencing who underwent hepatectomy for CLM (2005-2015). Survival after hepatectomy in patients with double mutation of APC and PIK3CA and others was analyzed. Predictors of pathologic response and survival were determined. The prognostic value of double mutation was evaluated with a separate cohort of 157 patients with CLM undergoing chemotherapy alone.

RESULTS

Forty-five patients had double mutation of APC and PIK3CA; 351 did not. Recurrence-free survival (RFS) and overall survival (OS) after hepatectomy were worse in patients with double mutation (3-year RFS, 3.1% vs 20% [P < 0.001]; 3-year OS, 44% vs 84% [P < 0.001]). Independent predictors of major pathologic response were bevacizumab use (odds ratio [OR] 2.22; P = 0.001), tumor size <3 cm (OR 1.97; P = 0.004), wild-type RAS (OR 2.00; P = 0.003), and absence of double mutation (OR 2.91; P = 0.002). Independent predictors of worse OS were primary advanced T category (hazard ratio [HR] 2.12; P = 0.021), RAS mutation (HR 1.74; P = 0.015), and double mutation (HR 3.09; P < 0.001). In the different medical cohort, patients with double mutation had worse 3-year OS of 18%, compared with 35% without double mutation (P = 0.023).

CONCLUSIONS

Double mutation of APC and PIK3CA predicts inferior response to preoperative chemotherapy and poor survival in patients with CLM.

Mast Cells, microRNAs and Others: The Role of Translational Research on Colorectal Cancer in the Forthcoming Era of Precision Medicine

Colorectal cancer (CRC) is a heterogeneous disease, molecularly and anatomically, that develops in a multi-step process requiring the accumulation of several genetic or epigenetic mutations that lead to the gradual transformation of normal mucosa into cancer. In fact, tumorigenesis is extremely complex, with many immunologic and non-immunologic factors present in the tumor microenvironment that can influence tumorigenesis. In the last few years, a role for mast cells (MCs), microRNAs (miRNAs), Kirsten rat sarcoma (KRAS) and v-raf murine sarcoma viral oncogene homologue B (BRAF) in cancer development and progression has been suggested, and numerous efforts have been made to thoroughly assess their correlation with CRC to improve patient survival and quality of life. The identification of easily measurable, non-invasive and cost-effective biomarkers, the so-called "ideal biomarkers", for CRC screening and treatment remains a high priority. The aim of this review is to discuss the emerging role of mast cells (MCs), microRNAs (miRNAs), KRAS and BRAF as diagnostic and prognostic biomarkers for CRC, evaluating their influence as potential therapy targets in the forthcoming era of precision medicine.

Conversion to complete resection with mFOLFOX6 with bevacizumab or cetuximab based on K-RAS status for unresectable colorectal liver metastasis (BECK study): Long-term results of survival

BACKGROUND/PURPOSE

To investigate the long-term outcome and entire treatment course of patients with technically unresectable CRLM who underwent conversion hepatectomy and to examine factors associated with conversion to hepatectomy.

METHODS

Recurrence and survival data with long-term follow-up were analyzed in the cohort of a multi-institutional phase II trial for technically unresectable colorectal liver metastases (the BECK study).

RESULTS

A total of 22/12 patients with K-RAS wild-type/mutant tumors were treated with mFOLFOX6 + cetuximab/bevacizumab. The conversion R0/1 hepatectomy rate was significantly higher in left-sided primary tumors than in right-sided tumors (75.0% vs 30.0%, P = .022). The median follow-up was 72.6 months. The 5-year overall survival (OS) rate in the entire cohort was 48.1%. In patients who underwent R0/1 hepatectomy (n = 21), the 5-year RFS rate and OS rate were 19.1% and 66.3%, respectively. At the final follow-up, seven patients had no evidence of disease, five were alive with disease, and 20 had died from their original cancer. All 16 patients who achieved 5-year survival underwent conversion hepatectomy, and 11 of them underwent further resection for other recurrences (median: 2, range: 1-4).

CONCLUSIONS

Conversion hepatectomy achieved a similar long-term survival to the results of previous studies in initially resectable patients, although many of them experienced several post-hepatectomy recurrences. Left-sided primary was found to be the predictor for conversion hepatectomy.

Platelet recovery correlates parenchymal volume recovery after liver resection

AIM

Platelet count seems to assess liver function and predict liver regeneration, but factors associated with liver regeneration remain unclear. This study analyzed the relationship between platelet recovery and postresection liver regeneration.

METHODS

Data from 343 candidates from 1245 consecutive patients with liver resection of more than Couinaud's segments were analyzed. Patients were divided into a low-platelet-recovery rate (LPRR) group (lowest 25%) or a control group on the basis of the platelet recovery rate on postoperative day (POD)7. Data were matched before analysis to adjust for operation scale. Trends in liver functional recovery were assessed, and liver volume recovery and remnant ischemic area was calculated using computed tomography volumetry. Factors predicting liver regeneration were analyzed.

RESULTS

In 78 matched-pair patients, the all-complications rate (42.3% vs. 26.9%, P = 0.002) and infectious complications rate (21.8% vs. 9.0%, P = 0.027) were significantly higher in the LPRR group than in controls. Trends in liver functional recovery did not differ significantly, whereas significant differences remained for platelet recovery. Parenchyma volume recovery was delayed in the LPRR group from POD7 (84.5% vs. 78.1, P < 0.01) to POD30 (92.5% vs. 85.6, P < 0.01). Platelet recovery rate on POD7 correlated negatively with ischemic liver volume as evaluated on POD2 by computed tomography (r = 0.691). Postoperative ischemic volume on POD2 (5.41 [1.98-11.21], P < 0.001), infectious complications (3.48 [1.44-7.37], P < 0.001), and multiple resection (1.67 [1.10-4.11], P = 0.011) predicted delayed platelet recovery rate on multivariate analysis.

CONCLUSION

Platelet recovery correlated with liver volume recovery and occurrence of complications. Large ischemic area might negatively impact regeneration after liver resection.

Does KRAS mutation status impact the risk of local recurrence after R1 vascular resection for colorectal liver metastasis? An observational cohort study

INTRODUCTION

R0 margin is the standard in the surgical treatment of colorectal liver metastases (CLM). Recently R1 surgery, at least that enabling CLM vessel-detachment (R1vasc), seems comparable to R0. As a possible background of that biologic factors could play some role. Among them, KRAS has been investigated in the present study.

METHODS

Patients who underwent curative surgery for CLM between 2008 and 2016 were identified. R0, R1vasc and parenchymal R1 (R1par; tumor exposure once dissected from the parenchyma) resections with known KRAS status were analyzed.

RESULTS

Of 1000 resection areas in 340 patients, 654 (65%) R0, 98 (10%) R1vasc and 248 (25%) R1par. In mutated KRAS (mKRAS), local recurrence (LR) was similar between R0 and R1vasc (per-patient 4,8% vs. 2%, p = 0.628; per-area 2,1% vs. 1,9%, p = 0.940), while higher in R1par (per-patient 25,4% and per-area 19,5%; p < 0.001 for both). In wild-type KRAS (wtKRAS), R0 had less LR compared to R1vasc (per-patient 7,6% vs 14,6%, p = 0.335; per-area 3,1% vs 13,3%, p = 0.012) and R1par (per-patient 18,3%, p = 0.060; per-area 9,9%, p = 0.013). KRAS did not impact LR in R0 (per-patient 7,6% vs. 4,8%, p = 0.491; per-area 3,1% vs. 2,1%, p = 0.555), while wtKRAS R1par had less LR compared to mKRAS R1par (per-patient 18,3% vs 25,4%, p = 0.404; per-area 9,9% vs 19,5%, p = 0.048). Inversely, LR was increased in wtKRAS R1vasc compared to mKRAS R1vasc (per-patient 14,6% vs 2%, p = 0.043; per-area 13,3% vs 1,9%, p = 0.046).

CONCLUSION

KRAS status does not impact LR risk in R0 resection. Inversely, R1vasc vs R1par LR risk is reduced in mKRAS, and increased in wtKRAS. If confirmed these results are of note.

Survival after repeat hepatectomy for recurrent colorectal liver metastasis: A review and meta-analysis of prognostic factors

BACKGROUND

Frequent recurrent hepatic metastasis after hepatic metastasectomy is a major obstacle in the treatment of colorectal liver metastasis (CRLM). We performed the present systematic review to evaluate the short- and long-term outcomes after repeat hepatectomy for recurrent CRLM and determine factors associated with survival in these patients.

DATA SOURCES

An electronic search of PubMed database was undertaken to identify all relevant peer-reviewed papers published in English between January 2000 and July 2018. Hazard ratios (HR) with 95% confidence interval (95% CI) were calculated for prognostic factors of overall survival (OS).

RESULTS

The search yielded 34 studies comprising 3039 patients, with a median overall morbidity of 23% (range 8%-71%), mortality of 0 (range 0-6%), and 5-year OS of 42% (range 17%-73%). Pooled analysis showed that primary T3/T4 stage tumor (HR = 1.94; 95% CI: 1.04-3.63), multiple tumors (HR = 1.49; 95% CI: 1.10-2.01), largest liver lesion ≥5 cm (HR = 1.89; 95% CI: 1.11-3.23) and positive surgical margin (HR = 1.80; 95% CI: 1.09-2.97) at initial hepatectomy, and high serum level of carcinoembryonic antigen (HR = 1.87; 95% CI: 1.27-2.74), disease-free interval ≤12 months (HR = 1.34; 95% CI: 1.10-1.62), multiple tumors (HR = 1.64; 95% CI: 1.32-2.02), largest liver lesion ≥5 cm (HR = 1.85; 95% CI: 1.34-2.56), positive surgical margin (HR = 2.25; 95% CI: 1.39-3.65), presence of bilobar disease (HR = 1.62; 95% CI: 1.19-2.20), and extrahepatic metastases (HR = 1.60; 95% CI: 1.23-2.09) at repeat hepatectomy were significantly associated with poor OS.

CONCLUSIONS

Repeat hepatectomy is a safe and effective therapy for recurrent CRLM. Long-term outcome is predicted mainly by factors related to repeat hepatectomy.

Gene mutation and surgical technique: Suggestion or more?

Advancements in chemotherapy and molecular targeted therapy have improved long-term outcomes for patients with resectable colorectal liver metastases (CLM). RAS mutation status was an original focus as a molecular biomarker as it predicted treatments response to anti-epidermal growth factor receptor agents. More recently, studies have incorporated somatic mutation data in analyses pertaining to surgical outcomes and prognosis. This evidenced-based review covers the implications of somatic mutations in patients undergoing resection of CLM.

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).

Prognostic impact of perihepatic lymph node metastases in patients with resectable colorectal liver metastases

BACKGROUND

Although perihepatic lymph node metastases (PLNMs) are known to be a poor prognosticator for patients with colorectal liver metastases (CRLMs), optimal management remains unclear. This study aimed to determine the risk factors for PLNMs, and the survival impact of their number and location in patients with resectable CRLMs.

METHODS

Data on patients with CRLM who underwent hepatectomy during 2003-2014 were analysed retrospectively. Recurrence-free (RFS) and overall (OS) survival were calculated according to presence, number and location of PLNMs. Risk factors for PLNM were evaluated by logistic regression analysis.

RESULTS

Of 1485 patients, 174 underwent lymphadenectomy, and 54 (31·0 per cent) had PLNM. Ten patients (5·7 per cent) who had lymphadenectomy and 176 (13·4 per cent) who did not underwent repeat hepatectomy. Survival of patients with PLNM was significantly poorer than that of patients without (RFS: 5·3 versus 13·8 months, P < 0·001; OS: 20·5 versus 71·3 months; P < 0·001). Median OS was significantly better in patients with para-aortic versus hepatoduodenal ligament PLNMs (58·2 versus 15·5 months; P = 0·011). Patients with three or more PLNMs had significantly worse median OS than those with one or two (16·3 versus 25·4 months; P = 0·039). The presence of primary tumour lymph node metastases (odds ratio 2·35; P = 0·037) and intrahepatic recurrence requiring repeat hepatectomy (odds ratio 5·61; P = 0·012) were significant risk factors for PLNM on multivariable analysis.

CONCLUSION

Patients undergoing repeat hepatectomy and those with primary tumour lymph node metastases are at significant risk of PLNM. Although PLNM is a poor prognostic factor independent of perihepatic lymph node station, patients with one or two PLNMs have a more favourable outcome than those with more PLNMs.

Impact of Prior Hepatectomy History on Local Tumor Progression after Percutaneous Ablation of Colorectal Liver Metastases

PURPOSE

To test the hypothesis that, given the current resection eligibility criteria for colorectal liver metastasis (CLM), prior hepatectomy would be associated with improved local tumor control and survival after percutaneous ablation of CLMs.

MATERIALS AND METHODS

This single-institution retrospective study included 82 consecutive patients with 97 CLMs treated with ablation (radiofrequency ablation, microwave ablation, or cryoablation) from January 2005 to December 2014. Local tumor progression-free survival (LTPFS), recurrence-free survival (RFS) at any organ, and overall survival (OS) were calculated using the Kaplan-Meier method from the time of ablation and compared between patients with (n = 49) and without (n = 33) prior hepatectomy. Cox regression models were used to identify LTPFS predictors.

RESULTS

Median overall follow-up period was 28 months (range, 4.5-132 months). Three-year actuarial LTPFS (patient level: 73% vs 34%, P < .001) was significantly higher in patients with than without prior hepatectomy, respectively. Similarly, 3-year RFS (23% vs 9.1%, P = .026) and OS (78% vs 48%, P = .003) were improved in patients with prior hepatectomy. At multivariate analysis, predictors of worse LTPFS were: no prior hepatectomy (hazard ratio [HR] 2.35, 95% confidence interval [CI] 1.02-5.45; P = .045), minimal ablation margin < 5 mm (HR 2.4, 95% CI 1.18-4.87; P = .016), and RAS-mutant tumor (HR 2.65, 95% CI 1.18-5.94; P = .019).

CONCLUSIONS

Prior hepatectomy for CLMs is associated with improved local tumor control after percutaneous ablation of post-resection-developed CLMs.

Remnant Liver Ischemia as a Prognostic Factor for Cancer-Specific Survival After Resection of Colorectal Liver Metastases

IMPORTANCE

Ischemia-reperfusion injury during hepatic resection has been shown to accelerate progression of liver cancer. However, the prognostic relevance of remnant liver ischemia (RLI) after resection of colorectal liver metastases (CLMs) is unknown to date.

OBJECTIVES

To assess the prognostic influence of RLI after resection of CLMs and to identify correlates of greater extent of RLI.

DESIGN, SETTING, AND PARTICIPANTS

This study was a retrospective analysis at The University of Texas MD Anderson Cancer Center based on prospectively collected data. The study identified 202 patients who underwent curative resection of CLMs between January 1, 2008, and December 31, 2014, and had enhanced computed tomographic images obtained within 30 days after surgery.

MAIN OUTCOMES AND MEASURES

Remnant liver ischemia was defined as reduced or absent contrast enhancement during the portal phase. Postoperative RLI was classified as grade 0 (none), 1 (marginal), 2 (partial), 3 (segmental), or 4 (necrotic) as previously defined. Experienced members of the surgical team retrospectively performed imaging assessments. Team members were masked to the postoperative outcomes. Survival after resection was stratified by RLI grade. Predictors of RLI grade 2 or higher and survival were identified.

RESULTS

Among 202 patients (median [range] age, 56 [27-87] years; 84 female), the RLI grades were as follows: grade 0 (105 patients), grade 1 (47 patients), grade 2 (45 patients), grade 3 (5 patients), and grade 4 (0 patients). Recurrence-free survival (RFS) and cancer-specific survival (CSS) rates after hepatic resection were worse in patients with RLI grade 2 or higher vs grade 1 or lower (RFS at 3 years, 6.4% [3 of 50] vs 39.2% [60 of 152]; P < .001 and CSS at 5 years, 20.7% [10 of 50] vs 63.7% [97 of 152]; P < .001). A largest metastasis at least 3 cm (OR, 2.74; 95% CI, 1.35-5.70; P = .005), multiple CLMs (OR, 2.51; 95% CI, 1.25-5.24; P = .009), and nonanatomic resection (odds ratio [OR], 3.29; 95% CI, 1.52-7.63; P = .002) were associated with RLI grade 2 or higher. A largest metastasis at least 3 cm (hazard ratio [HR], 1.70; 95% CI, 1.01-2.88; P = .045), mutant RAS (HR, 2.15; 95% CI, 1.27-3.64; P = .005), and RLI grade 2 or higher (HR, 2.90; 95% CI, 1.69-4.84; P < .001) were associated with worse CSS.

CONCLUSIONS AND RELEVANCE

In this study, remnant liver ischemia grade 2 or higher was associated with worse CSS after resection of CLMs. High-quality anatomic surgery to minimize RLI after resection is essential.

Curative-intent treatment of recurrent colorectal liver metastases: A comparison between ablation and resection

BACKGROUND

Liver-limited recurrence after resection of colorectal liver metastases is a frequent occurrence, and can in some cases be treated with curative intent. Although surgical re-resection remains standard of care, there is growing interest in the role of ablation in this setting. The aim of this study was to compare the outcomes after curative-intent ablation and resection in patients with recurrent colorectal liver metastases.

METHODS

We retrospectively analysed data from 366 consecutive patients who underwent liver resection for colorectal liver metastases between June 2010 and August 2015. Sixty-four developed liver-limited recurrence which was treated with curative intent, thirty-three (51.6%) by ablation and 31 (48.4%) by repeat resection.

RESULTS

Patient groups were well matched, with surgically resected patients showing higher pre-operative carcinoembryonic antigen levels and larger metastases. There were fewer post-operative complications and shorter length of stay in the ablation group (p < 0.02). After a median follow-up of 36.2 months, median overall survival was the same for both the resected and ablated groups at 33.3 months. Median progression-free survival was longer for patients treated with surgery (10.2 months) compared to ablation (4.3 months) (p = 0.002).

CONCLUSIONS

Ablation or resection for liver-limited recurrence after surgery for colorectal liver metastases is associated with improved overall survival compared with systemic chemotherapy alone, and should always be considered for patients with resectable liver recurrence. Although ablation seemed to be associated with a shorter progression-free survival, post-procedure morbidity was significantly lower. The choice between ablation and resection should therefore be made on a personalised basis.