Sarcopenic Obesity Promotes Recurrence in Patients Undergoing Resection for Colorectal Liver Metastases (CRLM).

BACKGROUND/AIM: Sarcopenia, is predictive of a worse outcome after resection for colorectal liver metastases (CRLM). Obesity leads to a metabolic double burden if sarcopenia is as present, prompting malignancy progression, known as sarcopenic obesity (SO). This study aimed to compare sarcopenia and SO in patients undergoing CRLM resection, to prognostic parameters. PATIENTS AND METHODS: The skeletal muscle index (SMI) defined sarcopenia using sex specific cut off values (48.4 cm2/m2 for females and 59.1 cm2/m2 for males) by calculating the preoperative muscle mass at the vertebral height L3 using OSIRIX DICOM viewer. SO was determined as sarcopenia in patients showing obesity, as shown via fat percentage measurements on the preoperative CT scan. Established prognostic parameters (KRAS status, TNM classification, inflammatory response) were evaluated against SMI and SO to assess their predictability for postoperative outcomes. RESULTS: A total of 251 patients (62% female, median age 68 years) were included. Sarcopenic patients showed a threefold higher risk for postoperative death as compared to non-sarcopenic patients (p=0.04). Prevalent SO increased this risk to fivefold (p=0.01) compared to non-sarcopenic patients. COX regression analysis revealed SO and KRAS positivity as independent prognostic factors for disease-free survival (SO: p=0.038; KRAS: p=0.041; TNM, tumor size, Charlson Comorbidity Index, platelet-to-lymphocyte ratio, neutrophil-to-lymphocyte ratio all not significant). Patients risk of death in case of KRAS positivity and SO was seven times higher (p=0.03). CONCLUSION: There seems to be a benefit in merging data on mutational status and muscle wasting in patients with CRLM to facilitate an individual, patient-tailored approach.

Incidence of Diabetes Mellitus and Its Impact on Outcomes in Patients Undergoing Surgical Pancreatectomy for Non-Malignant and Malignant Pancreatobiliary Diseases-A Retrospective Analysis.

Diabetes mellitus (DM) is a prominent risk factor for malignant and non-malignant pancreatic diseases. Furthermore, the presence of DM predicts an unfavourable outcome in people with pancreatic cancer. This retrospective observational study investigated 370 patients who underwent pancreatic resection surgery for various indications (84.3% in malignant indication) in a single surgery centre in Graz, Austria. The preoperative and postoperative diabetes statuses were evaluated according to surgery method and disease entity and predictors for diabetes development after surgery, as well as outcomes (survival and cancer recurrence) according to diabetes status, were analysed. In the entire cohort, the postoperative diabetes (postopDM) incidence was 29%. PostopDM occurred significantly more frequently in malignoma patients than in those with benign diseases (31.3% vs. 16.7%; p = 0.040, OR = 2.28). In the malignoma population, BMI, longer surgery duration, and prolonged ICU and hospital stay were significant predictors of diabetes development. The 1- and 2-year follow-ups showed a significantly increased mortality of people with postopDM in comparison to people without diabetes (HR 1-year = 2.02, p = 0.014 and HR 2-years = 1.56, p = 0.034). Local cancer recurrence was not influenced by the diabetes status. Postoperative new-onset diabetes seems to be associated with higher mortality of patients with pancreatic malignoma undergoing pancreatobiliary surgery.

Combining isotope ratios for provenancing Viking Age iron artefacts in the British Isles: a pilot study.

Stable and radiogenic isotope analysis - particularly using lead isotope analysis (LIA) - has previously been shown to be a useful tool for the provenancing of ancient metal artefacts of silver and copper and its alloys, but less progress has been made in the provenancing of iron artefacts, despite their importance and frequency in the archaeological record. In this pilot study we investigate for the first time the possibilities of iron isotope analysis in combination with trace strontium isotope analysis and LIA for the provenancing of iron objects believed to be from the Viking Age in the British Isles. Previous studies have shown that analysis of each of these isotopes can contribute to provenancing iron artefacts, but they are not individually resolutory. In this proof-of-concept study, we examine the Fe, Sr and Pb isotopes of 7 artefacts believed to derive from the Viking Age: 3 from Meols - a former Viking seaport on Wirral and 4 samples from the probable location of the AD 1066 Battle of Fulford in North Yorkshire. We also examine an additional artefact of unknown antiquity from Bebington Heath - a possible location of the AD 937 Battle of Brunanburh. Although the pilot data set is too small to make definitive conclusions, it has paved the way for a fuller study involving 100 samples (including 30 from the former Viking camp of Torksey, Lincolnshire) funded by the NEIF fund of the UK National Environmental Research Council. The high range of 87Sr/86Sr values in the present data set of 8 is beyond what would be expected for bog iron (with a cut-off ∼ 0.709) and suggests that mined ore was being used, a preliminary conclusion supported by the narrow range of Fe isotope data.

Treatment characteristics and outcomes of pure Acinar cell carcinoma of the pancreas - A multicentric European study on radically resected patients.

BACKGROUND: Acinar cell carcinomas (ACC) belong to the exocrine pancreatic malignancies. Due to their rarity, there is no consensus regarding treatment strategies for resectable ACC. METHODS: This is a retrospective multicentric study of radically resected pure pancreatic ACC. Primary endpoints were overall survival (OS) and disease-free survival (DFS). Further endpoints were oncologic outcomes related to tumor stage and therapeutic protocols. RESULTS: 59 patients (44 men) with a median age of 64 years were included. The median tumor size was 45.0 mm. 61.0% were pT3 (n = 36), nodal positivity rate was 37.3% (n = 22), and synchronous distant metastases were present in 10.1% of the patients (n = 6). 5-Years OS was 60.9% and median DFS 30 months. 24 out of 31 recurred systemically (n = 18 only systemic, n = 6 local and systemic). Regarding TNM-staging, only the N2-stage negatively influenced OS and DFS (p = 0.004, p = 0.001). Adjuvant treatment protocols (performed in 62.7%) did neither improve OS (p = 0.542) nor DFS (p = 0.159). In 9 cases, radical resection was achieved following neoadjuvant therapy. DISCUSSION: Radical surgery is currently the mainstay for resectable ACC, even for limited metastatic disease. Novel (neo)adjuvant treatment strategies are needed, since current systemic therapies do not result in a clear survival benefit in the perioperative setting.

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.

Gene Alterations, Mediators, and Artificial Intelligence in Colorectal Liver Metastases.

In this Special Issue of Cells, we seek articles that focus on the study of tumor biology in order to guide the scalpel [...].

Interdisciplinary Approach of Establishing PDAC Resectability: Biochemical, Radiological and NAT Regimen Prognostic Factors-Literature Review.

Background and Objectives: Pancreatic ductal adenocarcinoma (PDAC) remains one of the most lethal tumors, with a 5-year overall survival rate of less than 10%. To date, curative surgical resection remains the only favorable option for improving patients' survival. However, there is no consensus on which prognostic biochemical, radiological markers or neoadjuvant therapy regimens would benefit patients the most. Materials and Methods: A literature review was performed focusing on overall survival, R0 resection, 30-day mortality, adverse events (AEs), and elevated biomarkers. The electronic databases were searched from 2015 to 2020. Results: We reviewed 22 independent studies. In total, 20 studies were retrospective single- or multi-center reviews, while 2 studies were prospective Phase II trials. Conclusions: Patients with borderline resectable or locally advanced PDAC, who received neoadjuvant therapy (NAT) and surgery, have significantly better survival rates. The CA 19-9 biomarker levels in the neoadjuvant setting should be evaluated and considered as a specific biomarker for tumor resectability and overall survival.

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.

Life threatening rupture of the diaphragm after Covid 19 pneumonia: a case report.

BACKGROUND: The incidence of diaphragmatic rupture is low; however, it may be life threatening. Normally caused by blunt trauma, some cases are reported after pulmonary infections with extensive coughing. Covid 19 causes pulmonary infections and pneumonia and has been associated with weakening of the diaphragm after prolonged ventilation. We present a patient who suffered from diaphragmatic rupture 2 months after recovering from a severe Covid 19 pneumonia. CASE: A 71 years old male patient presented with massive thoraco-abdominal pain and severe dyspnea. At the time of admission, the patient was diagnosed with rupture of the diaphragm and developed cardiogenic shock. Intraoperatively there was a 4 cm diameter large rupture of the diaphragm with enterothorax (transverse colon, stomach, spleen, parts of the jejunum). Avulsion of the mesenteric arteries made a segmental resection of the jejunum together with the spleen necessary. A jejuno-jejunostomy was performed and organs were replaced into the abdomen. The rupture of the diaphragm underwent primary closure with non-resorbable suture material. The patient has shown an uneventful post-operative course, fully recovered and was discharged on day 11 after surgery. CONCLUSION: Covid 19 is a disease that is known to have various effects on different organs. The diaphragm is only paid heed in case of dysfunction. Also in the setting of Covid 19 it is not known as prominent effector organ. Nevertheless its affection by coughing caused by Covid 19 can lead to life threatening complications.

Nontumor related risk score: A new tool to improve prediction of prognosis after hepatectomy for colorectal liver metastases.

BACKGROUND: Prognostic stratification of patients with colorectal cancer liver metastasis based solely on tumor-related factors has only moderate discriminatory ability. We hypothesized that the inclusion of nontumor related factors can improve prediction of long-term prognosis of patients with colorectal cancer liver metastasis. METHODS: Nontumor related laboratory markers were assessed utilizing a training cohort from 2 U.S. institutions (n = 1,205). Factors independently associated with prognosis were used to develop a nontumor related prognostic score. The discriminatory ability, assessed by Harrell's C-statistics (C-index) and net reclassification improvement, was validated and compared with 3 commonly used tumor-related clinical risk scores: Fong clinical risk scores, m-clinical risk scores, and Genetic and Morphological Evaluation (GAME) score in an external validation cohort from 5 Asian (n = 1,307) and 3 European (n = 1,058) institutions. The discriminatory ability of nontumor related prognostic score combined with each of these 3 tumor-related prognostic scores was also estimated. RESULTS: Alkaline phosphatase (hazard ratio 1.43; 95% confidence interval, 1.11-1.84), albumin (hazard ratio 0.71; 95% confidence interval, 0.57-0.89), and mean corpuscular volume (hazard ratio 19.0, per log unit; 95% confidence interval, 4.79-75.0) were each independently associated with increased risk of death after resection of colorectal cancer liver metastasis (all P < .05). In turn, alkaline phosphatase, albumin, and mean corpuscular volume were combined to form a nontumor related prognostic score (2.942 × mean corpuscular volume + 0.399 × alkaline phosphatase-0.339 × albumin-12) × 10 (median, 16; range, 1-30). The nontumor related prognostic score had good-to-modest discriminatory ability in the external cohort (C-index = 0.58), which was comparable to the 3 established tumor-related prognostic scores (C-index: Fong clinical risk scores, 0.53, m-clinical risk scores, 0.55, GAME, 0.58). The addition of the nontumor related prognostic score to the tumor-related prognostic scores enhanced the discriminatory ability in the entire study cohort (C-index: nontumor related score+Fong, 0.60, nontumor related score+m-clinical risk scores, 0.61, nontumor related score+GAME, 0.64), as well reclassification improvement (42.5, 42.7%, and 21.2%, respectively). CONCLUSION: Nontumor related prognostic information may help improve the prognostic stratification of patients after resection of colorectal cancer liver metastasis. The nontumor related prognostic score may be combined with tumor-related prognostic tools to enhance prognostic stratification of patients with colorectal cancer liver metastasis.

Platelet to Lymphocyte Ratio Correlates With Carcinoma Progression in Pancreatic Intra Epithelial Neoplasia.

BACKGROUND/AIM: Pancreatic intraepithelial neoplasia (PanIN) is the most common precursor lesion to pancreatic adenocarcinoma (PDAC). Yet no criteria to quantify patients at risk for progression to PDAC with PanIN exist. Platelet to lymphocyte ratio is an inflammatory marker that has been associated with overall survival in patients with invasive malignancies including pancreatic cancer. Preoperative sarcopenia has been linked to more aggressive diseases in pancreatic neoplasms. We aimed to assess a relation between PLR and sarcopenia as predictors for tumor progression in patients undergoing pancreatic resection for IPMN. PATIENTS AND METHODS: We retrospectively reviewed 102 patients (46 females, 56 males) who underwent pancreatic resection for PanIn. PLR was calculated and quantified using a cutoff of 110, sarcopenia was quantified using the skeletal muscle index (SMI) on preoperative abdominal imaging. Both were co-evaluated with additional demographic, clinical, pathological, and imaging data for possible correlation with PanIN associated PDAC. RESULTS: PLR was significantly elevated in patients with PanIN - associated PDAC (p=0.006). In the multivariate analysis, invasive carcinomas were significantly more prevalent in patients with PLR above 110 (OR=4.06, 95%CI=3.91-4.12, p=0.04). Patients with elevated PLR had a two-times higher risk to die in the postoperative period (HR=2.26, 95%CI=1.04-2.21, p=0.001). Patients with elevated PLR, preoperative jaundice and sarcopenia were the most likely to have PanIN-associated PDAC (OR=3.48, 95%CI=2.98-8.41, p=0.02). CONCLUSION: PLR is an independent predictive marker for the presence of PanIN associated invasive carcinoma.

Mutant KRAS as a prognostic biomarker after hepatectomy for rectal cancer metastases: Does the primary disease site matter?

BACKGROUND: The prognostic implication of mutant KRAS (mKRAS) among patients with primary disease in the rectum remains unknown. METHODS: From 2000 to 2018, patients undergoing hepatectomy for colorectal liver metastases at 10 collaborating international institutions with documented KRAS status were surveyed. RESULTS: A total of 834 (65.8%) patients with primary colon cancer and 434 (34.2%) patients with primary rectal cancer were included. In patients with primary colon cancer, mKRAS served as a reliable prognostic biomarker of poor overall survival (OS) (hazard ratio [HR]: 1.58, 95% CI 1.28-1.95) in the multivariable analysis. Although a trend towards significance was noted, mKRAS was not found to be an independent predictor of OS in patients with primary rectal tumors (HR 1.34, 95% CI 0.98-1.80). For colon cancer, the specific codon impacted in mKRAS appears to reflect underlying disease biology and oncologic outcomes, with codon 13 being associated with particularly poor OS in patients with left-sided tumors (codon 12, HR 1.56, 95% CI 1.22-1.99; codon 13, HR 2.10 95% CI 1.43-3.08;). Stratifying the rectal patient population by codon mutation did not confer prognostic significance following hepatectomy. CONCLUSIONS: While the left-sided colonic disease is frequently grouped with rectal disease, our analysis suggests that there exist fundamental biologic differences that drive disparate outcomes. Although there was a trend toward significance of KRAS mutations for patients with primary rectal cancers, it failed to achieve statistical significance.

Sarcopenia and primary tumor location influence patients outcome after liver resection for colorectal liver metastases.

INTRODUCTION: Right-sided and left-sided colorectal cancer (CRC) is known to differ in their molecular carcinogenic pathways. The prevalence of sarcopenia is known to worsen the outcome after hepatic resection. We sought to investigate the prevalence of sarcopenia and its prognostic application according to the primary CRC tumor site. METHODS: 355 patients (62% male) who underwent liver resection in our center were identified. Clinicopathologic characteristics and long-term outcomes were stratified by sarcopenia and primary tumor location (right-sided vs. left-sided). Tumors in the coecum, right sided and transverse colon were defined as right-sided, tumors in the left colon and rectum were defined as left-sided. Sarcopenia was assessed using the skeletal muscle index (SMI) with a measurement of the skeletal muscle area at the level L3. RESULTS: Patients who underwent right sided colectomy (n = 233, 65%) showed a higher prevalence of sarcopenia (35.2% vs. 23.9%, p = 0.03). These patients also had higher chances for postoperative complications with Clavien Dindo >3 (OR 1.21 CI95% 0.9-1.81, p = 0.05) and higher odds for mortality related to CRC (HR 1.2 CI95% 0.8-1.8, p = 0.03).On multivariable analysis prevalence of sarcopenia remained independently associated with worse overall survival and disease free survival (overall survival: HR 1.47 CI 95% 1.03-2.46, p = 0.03; HR 1.74 CI95% 1.09-3.4, p = 0.05 respectively). CONCLUSION: Sarcopenia is known to have a worse prognosis in patients with CRLM and CRC. Depending on the primary location sarcopenia has a variable effect on the outcome after liver resection.

Toward an Optimized Staging System for Pancreatic Ductal Adenocarcinoma: A Clinically Interpretable, Artificial Intelligence-Based Model.

PURPOSE: The American Joint Committee on Cancer (AJCC) eighth edition schema for pancreatic ductal adenocarcinoma treats T and N stage as independent factors and uses positive lymph nodes (PLNs) to define N stage, despite data favoring lymph node ratio (LNR). We used artificial intelligence-based techniques to compare PLN with LNR and investigate interactions between tumor size and nodal status. METHODS: Patients who underwent pancreatic ductal adenocarcinoma resection between 2000 and 2017 at six institutions were identified. LNR and PLN were compared through shapley additive explanations (SHAP) analysis, with the best predictor used to define nodal status. We trained optimal classification trees (OCTs) to predict 1-year and 3-year risk of death, incorporating only tumor size and nodal status as variables. The OCTs were compared with the AJCC schema and similarly trained XGBoost models. Variable interactions were explored via SHAP. RESULTS: Two thousand eight hundred seventy-four patients comprised the derivation and 1,231 the validation cohort. SHAP identified LNR as a superior predictor. The OCTs outperformed the AJCC schema in the derivation and validation cohorts (1-year area under the curve: 0.681 v 0.603; 0.638 v 0.586, 3-year area under the curve: 0.682 v 0.639; 0.675 v 0.647, respectively) and performed comparably with the XGBoost models. We identified interactions between LNR and tumor size, suggesting that a negative prognostic factor partially overrides the effect of a concurrent favorable factor. CONCLUSION: Our findings highlight the superiority of LNR and the importance of interactions between tumor size and nodal status. These results and the potential of the OCT methodology to combine them into a powerful, visually interpretable model can help inform future staging systems.

Performance of two prognostic scores that incorporate genetic information to predict long-term outcomes following resection of colorectal cancer liver metastases: An external validation of the MD Anderson and JHH-MSK scores.

INTRODUCTION: Two novel clinical risk scores (CRS) that incorporate KRAS mutation status were developed: modified CRS (mCRS) and GAME score. However, they have not been tested in large national and international cohorts. The aim of this study was to validate the prognostic discrimination utility and determine the clinical usefulness of the two novel CRS. METHODS: Patients undergoing hepatectomy for CRLM (2000-2018) in 10 centers were included. The discriminatory abilities of mCRS, GAME, and Fong CRS were evaluated using Harrell's C-index and Akaike's Information Criterion. RESULTS: In the entire cohort, the C-index of the GAME score (0.61) was significantly higher than those of Fong score (0.57) and mCRS (0.54), while the C-Index of mCRS was significantly lower than that of Fong score. When we compared the models in the various geographical regions, the C-index of GAME score was significantly higher than that of mCRS in North America, Europe, and South America. The AIC of Fong score, mCRS, and GAME score were 14 405, 14 447, and 14 319, respectively. CONCLUSION: In conclusion, using the largest and most heterogenous population of CRLM patients with known KRAS status, this independent, external validation demonstrated that the GAME score outperforms both the traditional Fong score and mCRS.

The optimal cut-off values for tumor size, number of lesions, and CEA levels in patients with surgically treated colorectal cancer liver metastases: An international, multi-institutional study.

BACKGROUND AND OBJECTIVES: Despite the long-standing consensus on the importance of tumor size, tumor number and carcinoembryonic antigen (CEA) levels as predictors of long-term outcomes among patients with colorectal liver metastases (CRLM), optimal prognostic cut-offs for these variables have not been established. METHODS: Patients who underwent curative-intent resection of CRLM and had available data on at least one of the three variables of interest above were selected from a multi-institutional dataset of patients with known KRAS mutational status. The resulting cohort was randomly split into training and testing datasets and recursive partitioning analysis was employed to determine optimal cut-offs. The concordance probability estimates (CPEs) for these optimal cut offs were calculated and compared to CPEs for the most widely used cut-offs in the surgical literature. RESULTS: A total of 1643 patients who met eligibility criteria were identified. Following recursive partitioning analysis in the training dataset, the following cut-offs were identified: 2.95 cm for tumor size, 1.5 for tumor number and 6.15 ng/ml for CEA levels. In the entire dataset, the calculated CPEs for the new tumor size (0.52), tumor number (0.56) and CEA (0.53) cut offs exceeded CPEs for other commonly employed cut-offs. CONCLUSION: The current study was able to identify optimal cut-offs for the three most commonly employed prognostic factors in CRLM. While the per variable gains in discriminatory power are modest, these novel cut-offs may help produce appreciable increases in prognostic performance when combined in the context of future risk scores.

The Prognostic Impact of Primary Tumor Site Differs According to the KRAS Mutational Status: A Study By the International Genetic Consortium for Colorectal Liver Metastasis.

OBJECTIVE: To examine the prognostic impact of tumor laterality in colon cancer liver metastases (CLM) after stratifying by Kirsten rat sarcoma 2 viral oncogene homolog (KRAS) mutational status. BACKGROUND: Although some studies have demonstrated that patients with CLM from a right sided (RS) primary cancer fare worse, others have found equivocal outcomes of patients with CLM with RS versus left-sided (LS) primary tumors. Importantly, recent evidence from unresectable metastatic CRC suggests that tumor laterality impacts prognosis only in those with wild-type tumors. METHODS: Patients with rectal or transverse colon tumors and those with unknown KRAS mutational status were excluded from analysis. The prognostic impact of RS versus LS primary CRC was determined after stratifying by KRAS mutational status. RESULTS: 277 patients had a RS (38.6%) and 441 (61.4%) had a LS tumor. Approximately one-third of tumors (28.1%) harbored KRAS mutations. In the entire cohort, RS was associated with worse 5-year overall survival (OS) compared with LS (39.4% vs 50.8%, P = 0.03) and remained significantly associated with worse OS in the multivariable analysis (hazard ratio 1.45, P = 0.04). In wild-type patients, a worse 5-year OS associated with a RS tumor was evident in univariable analysis (43.7% vs 55.5%, P = 0.02) and persisted in multivariable analysis (hazard ratio 1.49, P = 0.01). In contrast, among patients with KRAS mutated tumors, tumor laterality had no impact on 5-year OS, even in the univariable analysis (32.8% vs 34.0%, P = 0.38). CONCLUSIONS: This study demonstrated, for the first time, that the prognostic impact of primary tumor side differs according to KRAS mutational status. RS tumors were associated with worse survival only in patients with wild-type tumors.

Prognostic Factors Change Over Time After Hepatectomy for Colorectal Liver Metastases: A Multi-institutional, International Analysis of 1099 Patients.

OBJECTIVE: To evaluate the changing impact of genetic and clinicopathologic factors on conditional overall survival (CS) over time in patients with resectable colorectal liver metastasis. BACKGROUND: CS estimates account for the changing likelihood of survival over time and may reveal the changing impact of prognostic factors as time accrues from the date of surgery. METHODS: CS analysis was performed in 1099 patients of an international, multi-institutional cohort. Three-year CS (CS3) estimates at the "xth" year after surgery were calculated as follows: CS3 = CS (x + 3)/CS (x). The standardized difference (d) between CS3 rates was used to estimate the changing prognostic power of selected variables over time. A d < 0.1 indicated very small differences between groups, 0.1 ≤ d < 0.3 indicated small differences, 0.3 ≤ d < 0.5 indicated moderate differences, and d ≥ 0.5 indicated strong differences. RESULTS: According to OS estimates calculated at the time of surgery, the presence of BRAF and KRAS mutations, R1 margin status, resected extrahepatic disease, patient age, primary tumor lymph node metastasis, tumor number, and carcinoembryonic antigen levels independently predicted worse survival. However, when temporal changes in the prognostic impact of these variables were considered using CS3 estimates, BRAF mutation dominated prognosis during the first year (d = 0.48), whereas surgeon-related variables (ie, surgical margin and resected extrahepatic disease) determined prognosis thereafter (d ≥ 0.5). Traditional clinicopathologic factors affected survival constantly, but only to a moderate degree (0.3 ≤ d < 0.5). CONCLUSIONS: The impact of genetic, surgery-related, and clinicopathologic factors on OS and CS3 changed dramatically over time. Specifically, BRAF mutation status dominated prognosis in the first year, whereas positive surgical margins and resected extrahepatic disease determined prognosis thereafter.