Ranking as a Procedure for Selecting a Replacement Variable in the Score Predicting the Survival of Patients Treated with Curative Intent for Colorectal Liver Metastases.

Background and Objectives: The issue of a missing variable precludes the external validation of many prognostic models. For example, the Liverpool score predicts the survival of patients undergoing surgical therapy for colorectal liver metastases, but it includes the neutrophil-lymphocyte ratio, which cannot be measured retrospectively. Materials and Methods: We aimed to find the most appropriate replacement for the neutrophil-lymphocyte ratio. Survival analysis was performed on data representing 632 liver resections for colorectal liver metastases from 2000 to 2020. Variables associated with the Liverpool score, C-reactive protein, albumins, and fibrinogen were ranked. The rankings were performed in four ways: The first two were based on the Kaplan-Meier method (log-rank statistics and the definite integral IS between two survival curves). The next method of ranking was based on univariate and multivariate Cox regression analyses. Results: The ranks were as follows: the radicality of liver resection (rank 1), lymph node infiltration of primary colorectal cancer (rank 2), elevated C-reactive protein (rank 3), the American Society of Anesthesiologists Classification grade (rank 4), the right-sidedness of primary colorectal cancer (rank 5), the multiplicity of colorectal liver metastases (rank 6), the size of colorectal liver metastases (rank 7), albumins (rank 8), and fibrinogen (rank 9). Conclusions: The ranking methodologies resulted in almost the same ranking order of the variables. Elevated C-reactive protein was ranked highly and can be considered a relevant replacement for the neutrophil-lymphocyte ratio in the Liverpool score. These methods are suitable for ranking variables in similar models for medical research.

The external validation of a difficulty scoring system for predicting the risk of intraoperative complications during laparoscopic liver resection.

BACKGROUND: This study aimed to externally validate and upgrade the recent difficulty scoring system (DSS) proposed by Halls et al. to predict intraoperative complications (IOC) during laparoscopic liver resection (LLR). METHODS: The DSS was validated in a cohort of 128 consecutive patients undergoing pure LLRs between 2008 and 2019 at a single tertiary referral center. The validated DSS includes four difficulty levels based on five risk factors (neoadjuvant chemotherapy, previous open liver resection, lesion type, lesion size and classification of resection). As established by the validated DSS, IOC was defined as excessive blood loss (> 775 mL), conversion to an open approach and unintentional damage to surrounding structures. Additionally, intra- and postoperative outcomes were compared according to the difficulty levels with usual statistic methods. The same five risk factors were used for validation done by linear and advanced nonlinear (artificial neural network) models. The study was supported by mathematical computations to obtain a mean risk curve predicting the probability of IOC for every difficulty score. RESULTS: The difficulty level of LLR was rated as low, moderate, high and extremely high in 36 (28.1%), 63 (49.2%), 27 (21.1%) and 2 (1.6%) patients, respectively. IOC was present in 23 (17.9%) patients. Blood loss of >775 mL occurred in 8 (6.2%) patients. Conversion to open approach was required in 18 (14.0%) patients. No patients suffered from unintentional damage to surrounding structures. Rates of IOC (0, 9.5, 55.5 and 100%) increased gradually with statistically significant value among difficulty levels (P < 0.001). The relations between the difficulty level, need for transfusion, operative time, hepatic pedicle clamping, and major postoperative morbidity were statistically significant (P < 0.05). Linear and nonlinear validation models showed a strong correlation (correlation coefficients 0.914 and 0.948, respectively) with the validated DSS. The Weibull cumulative distribution function was used for predicting the mean risk probability curve of IOC. CONCLUSION: This external validation proved this DSS based on patient's, tumor and surgical factors enables us to estimate the risk of intra- and postoperative complications. A surgeon should be aware of an increased risk of complications before starting with more complex procedures.

Outcomes of the Surgical Treatment for Adenocarcinoma of the Cardia - Single Institution Experience.

BACKGROUND: Adenocarcinomas at the cardia are biologically aggressive tumors with poor long-term survival following curative resection. For resectable adenocarcinoma of the cardia, mostly esophagus extended total gastrectomy or esophagus extended proximal gastric resection is performed; however, the surgical approach, transhiatal or transthoracic, is still under discussion. Postoperative morbidity, mortality and long-term survival were analyzed to evaluate the potential differences in clinically relevant outcomes. PATIENTS AND METHODS: Of altogether 844 gastrectomies performed between January 2000 and December 2016, 166 were done for the adenocarcinoma of the gastric cardia, which we analyzed with using the Cox proportional hazards model. RESULTS: 136 were esophagus extended total gastrectomy and 125 esophagus extended proximal gastric resection. A D2 lymphadenectomy was performed in 88.2%, splenectomy in 47.2%, and multivisceral resections in 12.4% of patients. R0 resection rate was 95.7%. The mean proximal resection margin on the esophagus was 42.45 mm. It was less than 21 mm in 9 patients. Overall morbidity regarding Clavien-Dindo classification (> 1) was altogether 28.6%. 15.5% were noted as surgical and 21.1% as medical complications. The 30-day mortality was 2.2%. The 5-year survival for R0 resections was 33.4%. Multivisceral resection, depth of tumor infiltration, nodal stage, and curability of the resection were identified as independent prognostic factors. CONCLUSIONS: Transhiatal approach for resection of adenocarcinoma of the cardia is a safe procedure for patients with Siewert II and III regarding the postoperative morbidity and mortality; moreover, long-term survival is comparable to transthoracic approach. The complications associated with thoracoabdominal approach can therefore be avoided with no impact on the rate of local recurrence.

Impact Factors for Perioperative Morbidity and Mortality and Repercussion of Perioperative Morbidity and Long-term Survival in Pancreatic Head Resection.

BACKGROUND: The focus of the present study was to reveal any impact factors for perioperative morbidity and mortality as well as repercussion of perioperative morbidity on long-term survival in pancreatic head resection. PATIENTS AND METHODS: In a retrospective study, clinic-pathological factors of 240 patients after pancreatic head (PD) or total resection were analyzed for correlations with morbidity, 30- and 90-day mortality, and long-term survival. According to Clavien-Dindo classification, all complications with grade II and more were defined as overall complications (OAC). OAC, all surgical (ASC), general (AGC) and some specific types of complications like leaks from the pancreatoenteric anastomosis (PEA) or pancreatic fistula (PF, type A, B and C), leaks from other anastomoses (OL), bleeding (BC) and abscesses (AA) were studied for correlation with clinic-pathological factors. RESULTS: In the 9-year period, altogether 240 patients had pancreatic resection. The incidence of OAC was 37.1%, ASC 29.2% and AGC 15.8%. ASC presented themselves as PL, OL, BC and AA in 19% (of 208 PD), 5.8%, 5.8%, and 2.5% respectively. Age, ASA score, amylase on drains, and pancreatic fistulas B and C correlated significantly with different types of complications. Overall 30- and 90-day mortalities were 5 and 7.9% and decreased to 3.5 and 5% in P2. CONCLUSIONS: High amylase on drains and higher mean age were independent indicators of morbidity, whereas PL and BC revealed as independent predictor for 30-day mortality, and physical status, OAC and PF C for 90-day mortality.

Simultaneous Pure Laparoscopic Resection of Primary Colorectal Cancer and Synchronous Liver Metastases: A Single Institution Experience with Propensity Score Matching Analysis.

BACKGROUND: The aim of the study was to compare the outcome of pure laparoscopic and open simultaneous resection of both the primary colorectal cancer and synchronous colorectal liver metastases (SCLM). PATIENTS AND METHODS: From 2000 to 2016 all patients treated by simultaneous resection were assessed for entry in this single center, clinically nonrandomized trial. A propensity score matching was used to compare the laparoscopic group (LAP) to open surgery group (OPEN). Primary endpoints were perioperative and oncologic outcomes. Secondary endpoints were overall survival (OS) and disease-free survival (DFS). RESULTS: Of the 82 patients identified who underwent simultaneous liver resection for SCLM, 10 patients underwent LAP. All these consecutive patients from LAP were matched to 10 comparable OPEN. LAP reduced the length of hospital stay (P = 0.044) and solid food oral intake was faster (P = 0.006) in this group. No patient undergoing the laparoscopic procedure experienced conversion to the open technique. No difference was observed in operative time, blood loss, transfusion rate, narcotics requirement, clinical risk score, resection margin, R0 resections rate, morbidity, mortality and incisional hernias rate. The two groups did not differ significantly in terms of the 3-year OS rate (90 vs. 75%; P = 0.842) and DFS rate (60 vs. 57%; P = 0.724). CONCLUSIONS: LAP reduced the length of hospital stay and offers faster solid food oral intake. Comparable oncologic and survival outcomes can be achieved. LAP is beneficial for well selected patients in high volume centers with appropriate expertise.

Single Nucleotide Polymorphisms in Genes MACC1, RAD18, MMP7 and SDF-1a As Prognostic Factors in Resectable Colorectal Cancer.

BACKGROUND: Colorectal cancer (CRC) represents one of the most common malignancies worldwide. Research has indicated that functional gene changes such as single nucleotide polymorphism (SNP) influence carcinogenesis and metastasis and might have an influence on disease relapse. The aim of our study was to evaluate the role of SNPs in selected genes as prognostic markers in resectable CRC. PATIENTS AND METHODS: In total, 163 consecutive patients treated surgically for CRC of stages I, II and III at the University Medical Centre in Maribor in 2007 and 2008 were investigated. DNA was isolated from formalin-fixed paraffin-embedded CRC tissue from the Department of Pathology and SNPs in genes SDF-1a, MMP7, RAD18 and MACC1 were genotyped using polymerase chain reaction followed by high resolution melting curve analysis or restriction fragment length polymorphism. RESULTS: We found worse disease-free survival (DFS) for patients with TT genotype of SNP rs1990172 in gene MACC1 (p = 0.029). Next, we found worse DFS for patients with GG genotype for SNP rs373572 in gene RAD18 (p = 0.020). Higher frequency of genotype GG of MMP7 SNP rs11568818 was found in patients with T3/T4 stage (p = 0.014), N1/N2 stage (p = 0.041) and with lymphovascular invasion (p = 0.018). For MACC1 rs1990172 SNP we found higher frequency of genotype TT in patients with T3/T4 staging (p = 0.024). Higher frequency of genotype GG of RAD18 rs373572 was also found in patients with T1/T2 stage with disease relapse (p = 0.041). CONCLUSIONS: Our results indicate the role of SNPs as prognostic factors in resectable CRC.

Pancreaticoduodenectomy for ductal adenocarcinoma of the pancreatic head with venous resection.

BACKGROUND: Recent reports have shown that patients with vascular tumour invasion who undergo concurrent vascular resection can achieve long-term survival rates equivalent to those without vascular involvement requiring pancreaticoduodenectomy alone. There is no consensus about which patients benefit from the portal-superior mesenteric vein resection and there is no consensus about the best surgical technique of vessel reconstruction (resection with or without graft reconstruction). As published series are small the aim of this study was to evaluate our experience in pancreatectomies with en bloc vascular resection and reconstruction of vessels. METHODS: Review of database at University Clinical Centre Maribor identified 133 patients (average age 65.4 ± 8.6 years, 69 female patients) who underwent pancreatoduodenectomy between January 2006 and August 2014. Clinical data, operative results, pathological findings and postoperative outcomes were collected prospectively and analyzed. Current literature and our experience in pancreatectomies with en bloc vascular resection and reconstruction of portal vein are reviewed. RESULTS: Twenty-two patients out of 133 (16.5%) had portal vein-superior mesenteric vein resection and portal vein reconstruction (PVR) during pancreaticoduodenectomy. In fourteen patients portal vein was reconstructed without the use of synthetic vascular graft. In these series two types of venous reconstruction were performed. When tumour involvement was limited to the superior mesenteric vein (SPV) or portal vein (PV) such that the splenic vein could be preserved, and vessels could be approximated without tension a primary end-to-end anastomosis was performed. When tumour involved the SMV-splenic vein confluence, splenic vein ligation was necessary. In the remaining eight procedures interposition graft was needed. Dacron grafts with 10 mm diameter were used. There was no infection after dacron grafting. One patient had portal vein thrombosis after surgery: it was thrombosis after primary reconstruction. There were no thromboses in patients with synthetic graft interposition. There were no significant differences in postoperative morbidity, mortality or grades of complication between groups of patients with or without a PVR. Median survival time in months was in a group with vein resection 16.13 months and in a group without vein resection 15.17 months. Five year survival in the group without vein resection was 19.5%. Comparison of survival curves showed equal hazard rates with log-rank p = 0.090. CONCLUSIONS: Survival of patients with pancreatic cancer who undergo an R0 resection with reconstruction was comparable to those who have a standard pancreaticoduodenectomy with no added mortality or morbidity. Synthetic graft appeared to be an effective and safe option as an interposition graft for portomesenteric venous reconstruction after pancreaticoduodenectomy.

CA19-9 serum levels predict micrometastases in patients with gastric cancer.

BACKGROUND: We explored the prognostic value of the up-regulated carbohydrate antigen (CA19-9) in node-negative patients with gastric cancer as a surrogate marker for micrometastases. PATIENTS AND METHODS: Micrometastases were determined using reverse transcription quantitative polymerase chain reaction (RT-qPCR) for a subgroup of 30 node-negative patients. This group was used to determine the cut-off for preoperative CA19-9 serum levels as a surrogate marker for micrometastases. Then 187 node-negative T1 to T4 patients were selected to validate the predictive value of this CA19-9 threshold. RESULTS: Patients with micrometastases had significantly higher preoperative CA19-9 serum levels compared to patients without micrometastases (p = 0.046). CA19-9 serum levels were significantly correlated with tumour site, tumour diameter, and perineural invasion. Although not reaching significance, subgroup analysis showed better five-year survival rates for patients with CA19-9 serum levels below the threshold, compared to patients with CA19-9 serum levels above the cut-off. The cumulative survival for T2 to T4 node-negative patients was significantly better with CA19-9 serum levels below the cut-off (p = 0.04). CONCLUSIONS: Preoperative CA19-9 serum levels can be used to predict higher risk for haematogenous spread and micrometastases in node-negative patients. However, CA19-9 serum levels lack the necessary sensitivity and specificity to reliably predict micrometastases.

Can we improve the clinical risk score? The prognostic value of p53, Ki-67 and thymidylate synthase in patients undergoing radical resection of colorectal liver metastases.

OBJECTIVES: The aim of this study was to assess whether biological markers can provide prognostic information additional to that supplied by the clinical risk score (CRS) in patients with colorectal liver metastases. METHODS: A retrospective review of a prospectively maintained database was conducted. Patients selected for this study were treated between 1996 and 2011 with potentially curative liver surgery. Expressions of p53, Ki-67 and thymidylate synthase were assayed using immunohistochemical techniques on tissue microarrays. RESULTS: A total of 98 (24%) of 406 patients met the inclusion criteria. The median follow-up was 103 months. Analysis revealed a correlation between p53 protein overexpression and high CRS (P = 0.058). Following multivariate analysis, only high CRS remained as an independent negative prognostic predictor of survival (P = 0.018), as well as an indicator of early recurrence of disease (P = 0.010). Of the biological markers investigated, only Ki-67 overexpression was identified as a positive predictor of survival on multivariate analysis (P = 0.038). CONCLUSIONS: Ki-67 overexpression was a positive predictor of survival. Only high CRS remained an independent negative prognostic predictor.

The impact of obesity on short-term outcomes after the laparoscopic liver resection: a single-institution experience.

Introduction: Obesity is a major public health problem and a well-known cause of multiple comorbidities. With the increasing application of minimally invasive surgery for benign and malignant liver lesions, the results of laparoscopic liver resection (LLR) in obese patients are of great interest. Aim: To evaluate the short-term operative outcomes after LLR in obese patients and compare them to patients with normal weight and overweight. Material and methods: All 235 consecutive patients undergoing LLR from 2008 to 2023 were retrospectively analysed. Patients were categorized into 3 groups based on their body mass index (BMI): normal weight (18.5-24.9 kg/m2), overweight (25-29.9 kg/m2), and obese (≥ 30 kg/m2). The groups were then compared regarding preoperative data and intra- and postoperative outcomes. Results: Despite higher ASA score and associated comorbidities in the obese group, there were no significant differences in intraoperative complication (blood loss, damage to surrounding structures, conversion rate) between BMI groups (20.8% vs. 16.8% vs. 22.7%, p = 0.619). There were no significant differences in overall morbidity (34.7% vs. 27.7% vs. 29.5%, p = 0.582), as well as major morbidity (15.9% vs. 11.8% vs. 11.4%, p = 0.784) or mortality rates (1.4% vs. 1.7% vs. 0.0%, p = 1.000). Univariate logistic regression did not show BMI or obesity as a predictive variable for intraoperative complication. Conclusions: Obesity is not a significant, strong risk factor for worse short-term outcomes, and LLR may be considered also in patients with overweight and obesity.

Two-stage hepatectomy in resection of colorectal liver metastases - a single-institution experience with case-control matching and review of the literature.

BACKGROUND: Two-stage hepatectomy (TSH) has been proposed for patients with bilateral liver tumours who have a high risk of posthepatectomy liver failure after one-stage hepatectomy (OSH). This study aimed to determine the outcomes of TSH for extensive bilateral colorectal liver metastases. PATIENTS AND METHODS: A retrospective review of a prospectively maintained database of liver resections for colorectal liver metastases was conducted. The TSH group was compared to the OSH group in terms of perioperative outcomes and survival. Case-control matching was performed. RESULTS: A total of 632 consecutive liver resections for colorectal liver metastases were performed between 2000 and 2020. The study group (TSH group) consisted of 15 patients who completed TSH. The control group included 151 patients who underwent OSH. The case-control matching-OSH group consisted of 14 patients. The major morbidity and 90-day mortality rates were 40% and 13.3% in the TSH group, 20.5% and 4.6% in the OSH group and 28.6% and 7.1% in the case-control matching-OSH group, respectively. The recurrence-free survival, median overall survival, and 3- and 5-year survival rates were 5 months, 21 months, 33% and 13% in the TSH group; 11 months, 35 months, 49% and 27% in the OSH group; and 8 months, 23 months, 36% and 21%, respectively, in the case-control matching-OSH group, respectively. CONCLUSIONS: TSH used to be a favourable therapeutic choice in a select population of patients. Now, OSH should be preferred whenever feasible because it has lower morbidity and equivalent oncological outcomes to those of completed TSH.

Rectal cancer treatment and survival--comparison of two 5-year time intervals.

In last two decades there was a huge step forward concerning rectal cancer treatment. The aim of our study was comparison of two time intervals regarding the methods of treatment and results of radical rectal cancer surgery. 407 patients operated on for rectal cancer were included in study. Those were patients with elective radical resection of solitary rectal tumor who survived first month after the operation. Patients were divided in two groups regarding the time of operation. In group one were patients operated on between 1996 and 2000 and in group two patients operated on between 2001 and 2005. We compared our results in both intervals with special interest about type of operation considering localization of the tumor, local recurrence and cancer related survival. Significant differences were found between two groups. There were more sphincter saving operations in second group, less local recurrences and better survival than in first group. This study observed significant improvements at recurrence rates and total survival for patients operated on rectal cancer.

Calcium imaging in intact mouse acinar cells in acute pancreas tissue slices.

The physiology and pathophysiology of the exocrine pancreas are in close connection to changes in intra-cellular Ca2+ concentration. Most of our knowledge is based on in vitro experiments on acinar cells or acini enzymatically isolated from their surroundings, which can alter their structure, physiology, and limit our understanding. Due to these limitations, the acute pancreas tissue slice technique was introduced almost two decades ago as a complementary approach to assess the morphology and physiology of both the endocrine and exocrine pancreas in a more conserved in situ setting. In this study, we extend previous work to functional multicellular calcium imaging on acinar cells in tissue slices. The viability and morphological characteristics of acinar cells within the tissue slice were assessed using the LIVE/DEAD assay, transmission electron microscopy, and immunofluorescence imaging. The main aim of our study was to characterize the responses of acinar cells to stimulation with acetylcholine and compare them with responses to cerulein in pancreatic tissue slices, with special emphasis on inter-cellular and inter-acinar heterogeneity and coupling. To this end, calcium imaging was performed employing confocal microscopy during stimulation with a wide range of acetylcholine concentrations and selected concentrations of cerulein. We show that various calcium oscillation parameters depend monotonically on the stimulus concentration and that the activity is rather well synchronized within acini, but not between acini. The acute pancreas tissue slice represents a viable and reliable experimental approach for the evaluation of both intra- and inter-cellular signaling characteristics of acinar cell calcium dynamics. It can be utilized to assess many cells simultaneously with a high spatiotemporal resolution, thus providing an efficient and high-yield platform for future studies of normal acinar cell biology, pathophysiology, and screening pharmacological substances.

Evaluation of the Iwate Model for Predicting the Difficulty of Laparoscopic Liver Resection: Does Tumor Size Matter?

BACKGROUND: This study aimed to externally validate the Iwate scoring model and its prognostic value for predicting the risks of intra- and postoperative complications of laparoscopic liver resection. METHODS: Consecutive patients who underwent pure laparoscopic liver resection between 2008 and 2019 at a single tertiary center were included. The Iwate scores were calculated according to the original proposition (four difficulty levels based on six indices). Intra- and postoperative complications were compared across difficulty levels. Fitting the obtained data to the cumulative density function of the Weibull distribution and a linear function provided the mean risk curves for intra- and postoperative complications, respectively. RESULTS: The difficulty levels of 142 laparoscopic liver resections were scored as low, intermediate, advanced, and expert level in 41 (28.9%), 53 (37.3%), 32 (22.5%), and 16 (11.3%) patients, respectively. Intraoperative complications were detected in 26 (18.3%) patients and its rates (2.4%, 7.5%, 34.3%, and 62.5%) increased gradually with statistically significant values among difficulty levels (P Ë‚ 0.001). Major postoperative complications occurred in 21 (14.8%) patients and its rates (4.8%, 5.6%, 28.1%, 43.7%; P Ë‚ 0.001) showed the same trend as for intraoperative complications. Then, the mean risk curves of both complications were obtained. Due to outliers, a new threshold for a tumor size index was proposed at 38 mm. The repeated analysis showed improved results. CONCLUSIONS: The Iwate scoring model predicts the probability of complications across difficulty levels. Our proposed tumor size threshold (38 mm) improves the quality of the prediction. The model is upgraded by a probability of complications for every difficulty score.

The learning curve of laparoscopic liver resection utilising a difficulty score.

BACKGROUND: This study aimed to quantitatively evaluate the learning curve of laparoscopic liver resection (LLR) of a single surgeon. PATIENTS AND METHODS: A retrospective review of a prospectively maintained database of liver resections was conducted. 171 patients undergoing pure LLRs between April 2008 and April 2021 were analysed. The Halls difficulty score (HDS) for theoretical predictions of intraoperative complications (IOC) during LLR was applied. IOC was defined as blood loss over 775 mL, unintentional damage to the surrounding structures, and conversion to an open approach. Theoretical association between HDS and the predicted probability of IOC was utilised to objectify the shape of the learning curve. RESULTS: The obtained learning curve has resulted from thirteen years of surgical effort of a single surgeon. It consists of an absolute and a relative part in the mathematical description of the additive function described by the logarithmic function (absolute complexity) and fifth-degree regression curve (relative complexity). The obtained learning curve determines the functional dependency of the learning outcome versus time and indicates several local extreme values (peaks and valleys) in the learning process until proficiency is achieved. CONCLUSIONS: This learning curve indicates an ongoing learning process for LLR. The proposed mathematical model can be applied for any surgical procedure with an existing difficulty score and a known theoretically predicted association between the difficulty score and given outcome (for example, IOC).

Prediction of liver metastases after gastric cancer resection with the use of learning vector quantization neural networks.

OBJECTIVE: The aim of our study was to determine whether learning vector quantization neural networks could be used to predict liver metastases after a gastric cancer surgery. BACKGROUND: The prediction of tumor recurrence is invaluable for tailoring specific treatment and follow-up strategies for gastric cancer patients. At present, it is still impossible to make reliable predictions of tumor progression. The use of complex mathematical models such as neural networks has already been implemented for the study of various pathophysiological mechanisms, but to date they have never been used for predicting liver metastases after gastric cancer resection. METHODS: A total of 213 patients operated for gastric cancer between 1999 and 2005 were included in our study. They were stratified in a model development (140 patients) and validation group (73 patients). With the use of an auxiliary regression network, seven clinicopathological variables were selected to predict liver metastases. RESULTS: Forty-one patients developed liver metastases (19.2%). The longest follow-up was 2,754 days. Most liver metastases occurred in the first 799 days after discharge. All predictions were compared to actual recurrences with a two by two contingence table. The determined sensitivity and specificity for the development sample were 71 and 96.1%, respectively. The values for the test sample were 66.7 and 97.1%, respectively. The significance of the model was determined using various post-hoc tests, which all confirmed the effectiveness of our model. CONCLUSION: The presented model exhibited a high negative predictive value and reasonable high sensitivity for liver metastases. To improve sensitivity, the inclusion of more patients and perhaps biological markers is still necessary.

Intraoperative electrochemotherapy of colorectal liver metastases: A prospective phase II study.

BACKGROUND AND OBJECTIVES: A previous pilot study proved the feasibility, safety and efficacy of electrochemotherapy in the treatment of colorectal liver metastases. The aim of this study was to evaluate long-term effectiveness and safety of electrochemotherapy in the treatment of unresectable colorectal liver metastases. PATIENTS AND METHODS: In this prospective phase II study, patients with metachronous colorectal liver metastases were included. In all patients, at least one metastasis was unresectable due to its central location or a too-small future remnant liver volume. Patients were treated by electrochemotherapy using intravenously administered bleomycin during open surgery. Treated were 84 metastases in 39 patients. Local tumor control, progression-free survival and overall survival were evaluated. RESULTS: The objective response was 75% (63% CR, 12% PR). The median duration of the response was 20.8 months for metastases in CR and 9.8 months for metastases in PR. The therapy was significantly more effective for metastases smaller than 3 cm in diameter than for larger ones. There was no difference in response according to the metastatic location, i.e., metastases in central vs. peripheral locations. Progression-free survival was better in patients who responded well to electrochemotherapy compared to those metastases that had a partial response or progressive disease. However, there was no difference in overall survival, with a median of 29.0 months. CONCLUSIONS: Electrochemotherapy has proven to be safe and effective in the treatment of colorectal liver metastases, with a durable response. It provides local tumor control that enables patients with unresectable metastases to receive further treatments.

The validity of clinical risk score for patients undergoing liver resection for colorectal metastases.

BACKGROUND/AIMS: The purpose of this study was to examine the validity of the clinical risk score (CRS) for a selection of patients for surgery. METHODOLOGY: In the period of January 1996 to June 2007, 169 patients underwent their first surgical and/or local ablative therapy for CRLM. This study assesses five preoperative prognostic criteria which define the CRS (nodal status of the primary tumor, the disease-free interval, the number of hepatic metastases, the preoperative CEA level, and the size of the largest metastasis). In the present study was analyzed the calculated CRS with respect to patient's postoperative survival. RESULTS: An individual CRS was found to be predictive of survival. CRS stratified into two groups (CRS scores 0-2 and 3-5) were also found to be predictive of survival, with 5-year survival rates of 41% and 13%, respectively. CRS stratified into three groups (CRS scores 0-1; 2-3 and 4-5) were found predictive of survival as well, with 5-year survival rates of 72.7%, 21% and 4.6%, respectively. CONCLUSIONS: Immediate hepatic resection is reasonable in patients with CRS 0 to 1. In patients with CRS 2 to 3, chemotherapy may be required in addition to hepatic resection. In patients with CRS 4 to 5, hepatic resection is probably reasonable only if there is a response to chemotherapy.

Factors affecting the morbidity and mortality of diverting stoma closure: retrospective cohort analysis of twelve-year period.

Background Diverting stoma is often performed in rectal cancer surgery for reducing the consequences of possible anastomotic failure. Closing of stoma follows in most cases after a few months. The aim of our study was to evaluate morbidity and mortality after diverting stoma closure and to identify risk factors for complications of this procedure. Patients and methods At our department, we have performed a retrospective cohort analysis of data for 260 patients with diverting stoma closure from 2003 to 2015. Age, stoma type, patient's preoperative ASA score, surgical technique and time to stoma closure were investigated as factors which could influence the complication rate. Results 218 patients were eligible for investigation. Postoperative complications developed in 54 patients (24.8%). Most common complications were postoperative ileus (10%) and wound infection (5%). Four patients died (1.8%). There was no effect on complication rate regarding type of stoma, closing technique, patient's ASA status and patient age. The only factor influencing the complication rate was the time to stoma closure. We found that patients which had the stoma closed prior to 8 months after primary surgery had lower overall complication rate (p<0. 05). Conclusions To reduce overall complication rate, our data suggest a shorter period than 8 months after primary surgery before closure of diverting stoma. As diverting stoma closure is not a simple operation, all strategies should be taken to reduce significant morbidity and mortality rate.

Impact of perioperative treatment on survival of resectable gastric cancer patients after D2 lymphadenectomy: a single European centre propensity score matching analysis.

Background To determine the effects of perioperative treatment of gastric cancer patients, we conducted an analysis with propensity score matched patient groups to determine the role of perioperative chemotherapy in patients after D2 lymphadenectomy. Patients and methods From our database of 1563 patients, 482 patients were selected with propensity score matching and divided into two balanced groups: 241 patients in the surgery only group and 241 patients in the perioperative group. The long-term results of treatment were compared between the two groups. Results Most of the included patients received radio-chemotherapy with capecitabine (n = 111; 46%) and perioperative chemotherapy with epirubicin, oxalliplatin and capecitabine (n = 91; 37.7%). 92.9% of the patients received a D2 lymph node dissection. Perioperative morbidity was similar between surgery only (18.3%) and perioperative treatment groups (20.7%) (p = 0.537). The perioperative mortality was not influenced by perioperative treatment. A pathological response was observed in 12.5% of patients. The overall 5-year and median survivals were significantly higher in the perioperative treatment group (50.5%; 51.7 moths) compared to surgery only group (41.8%; 34.9 months; p = 0.038). The subgroup analysis revealed that only patients with the TNM stages T3 (p = 0.028), N2 (p = 0.009), N3b (p = 0.043), and UICC stages IIIb (p = 0.003) and IIIc (p = 0.03) significantly benefit from perioperative treatment. Conclusions Perioperative treatment in radically resected gastric cancer patients after D2 lymphadenectomy was beneficial in stages IIIb and IIIc. The effects of perioperative treatment in lower stages could be negated by the effects of the radical surgery in lower stages and in higher stages by the biology of the disease.