Critical appraisal of surgical margins according to KRAS status in liver resection for colorectal liver metastases: Should surgical strategy be influenced by tumor biology?

BACKGROUND

KRAS mutation is a negative prognostic factor for colorectal liver metastases. Several studies have investigated the resection margins according to KRAS status, with conflicting results. The aim of the study was to assess the oncologic outcomes of R0 and R1 resections for colorectal liver metastases according to KRAS status.

METHODS

All patients who underwent resection for colorectal liver metastases between 2010 and 2015 with available KRAS status were enrolled in this multicentric international cohort study. Logistic regression models were used to investigate the outcomes of R0 and R1 colorectal liver metastases resections according to KRAS status: wild type versus mutated. The primary outcomes were overall survival and disease-free survival.

RESULTS

The analysis included 593 patients. KRAS mutation was associated with shorter overall survival (40 vs 60 months; P = .0012) and disease-free survival (15 vs 21 months; P = .003). In KRAS-mutated tumors, the resection margin did not influence oncologic outcomes. In multivariable analysis, the only predictor of disease-free survival and overall survival was primary tumor location (P = .03 and P = .03, respectively). In KRAS wild-type tumors, R0 resection was associated with prolonged overall survival (74 vs 45 months, P < .001) and disease-free survival (30 vs 17 months, P < .001). The multivariable model confirmed that R0 resection margin was associated with prolonged overall survival (hazard ratio = 1.43, 95% confidence interval: 1.01-2.03) and disease-free survival (hazard ratio = 1.42; 95% confidence interval: 1.06-1.91).

CONCLUSIONS

KRAS-mutated colorectal liver metastases showed more aggressive tumor biology with inferior overall survival and disease-free survival after liver resection. Although R0 resection was not associated with improved oncologic outcomes in the KRAS-mutated tumors group, it seems to be of paramount importance for achieving prolonged long-term survival in KRAS wild-type tumors.

Long-Term Outcomes of Perioperative Versus Neoadjuvant Chemotherapy for Resectable Colorectal Liver Metastases: An International Multicentre Propensity-Score Matched Analysis with Stratification by Contemporary Risk-Scoring

BACKGROUND

There is still debate regarding the principal role and ideal timing of perioperative chemotherapy (CTx) for patients with upfront resectable colorectal liver metastases (CRLM). This study assesses long-term oncological outcomes in patients receiving neoadjuvant CTx only versus those receiving neoadjuvant combined with adjuvant therapy (perioperative CTx).

METHODS

International multicentre retrospective analysis of patients with CRLM undergoing liver resection between 2010 and 2015. Characteristics and outcomes were compared before and after propensity score matching (PSM). Primary endpoints were long-term oncological outcomes, such as recurrence-free survival (RFS) and overall survival (OS). Furthermore, stratification by the tumour burden score (TBS) was applied.

RESULTS

Of 967 patients undergoing hepatectomy, 252 were analysed, with a median follow-up of 45 months. The unmatched comparison revealed a bias towards patients with neoadjuvant CTx presenting with more high-risk patients (p = 0.045) and experiencing increased postoperative complications ≥Clavien-Dindo III (20.9% vs. 8%, p = 0.003). Multivariable analysis showed that perioperative CTx was associated with significantly improved RFS (hazard ratio [HR] 0.579, 95% confidence interval [CI] 0.420-0.800, p = 0.001) and OS (HR 0.579, 95% CI 0.403-0.834, p = 0.003). After PSM (n = 180 patients), the two groups were comparable regarding baseline characteristics. The perioperative CTx group presented with a significantly prolonged RFS (HR 0.53, 95% CI 0.37-0.76, p = 0.007) and OS (HR 0.58, 95% CI 0.38-0.87, p = 0.010) in both low and high TBS patients.

CONCLUSIONS

When patients after resection of CRLM are able to tolerate additional postoperative CTx, a perioperative strategy demonstrates increased RFS and OS in comparison with neoadjuvant CTx only in both low and high-risk situations.

Sleep deprivation among surgical residents: Does it affect performance while practising a laparoscopic intestinal anastomosis?

INTRODUCTION

To assess the impact of fatigue due to incorrect night rest in the performance of a laparoscopic manual anastomosis.

METHODS

A prospective study evaluating the results from the realization of a manual endotrainer entero-enteral anastomosis performed by residents in terms of fatigue caused by inadequate nightly rest. Two groups were established; the FATIGUE group (F): anastomosis performed by residents coming off shift who slept less than seven hours and the REST group(R), being those who slept at home for more than 7 h. The time taken, length of the anastomosis and quality of such were compared based on 4 parameters: Air leak test, correct tension on the suture line, accurate opposition of the edges and optimal distance between stitches.

RESULTS

402 anastomoses were studied (211 rest group, 191 fatigue group). In the fatigue group leaks were detected in 33.5% anastomoses, as opposed to 19.4% in the rest group (P < .01). El rest group performed the anastomosis in 56.75 min and the fatigue group in 61,49 min (P = .006). There were no significant differences in the others parameters.

CONCLUSIONS

Fatigue increases the risk of leakage and the time to do the exercise.

Liver resection in elderly patients with extensive CRLM: Are we offering an adequate treatment? A propensity score matched analysis

BACKGROUND

Data on the management of elderly patients with extensive colorectal liver metastases (CRLM) are scarce and conflicting. This study assesses differences in management and long-term oncological outcomes between older and younger patients with CRLM and a high Tumour Burden Score (TBS).

METHODS

International multicentre retrospective study on patients with CRLM and a category 3 TBS, submitted to liver resection. Patients were divided into two groups according to their age (younger and older than 75) and were compared using propensity score matching (PSM) analysis and multivariable regression models. Differences in management and oncological outcomes including recurrence-free survival (RFS) and overall survival (OS) were assessed.

RESULTS

The study included 386 patients, median follow-up was 48 months. The unmatched comparison revealed a higher ASA score (p = 0.035), less synchronous CRLM (47% vs 68%, p = 0.003), a lower median number of lesions (1 vs 3, p = 0.004) and less perioperative chemotherapy (CTx) (66% vs 88%, p < 0.001) in the elderly group. Despite the absence of CTx being an independent predictor of decreased RFS and OS (HR 0.760, p = 0.044 and HR 0.719, p = 0.049, respectively), the elderly group still received less CTx (OR 0.317, p = 0.001) than the younger group. After PSM (n = 100 patients), the two groups were comparable, however, CTx administration was still significantly lower in the elderly group.

CONCLUSION

Liver resection should be considered in patients aged 75 and older, even if they present with extensive liver disease. Despite CTx being associated with improved oncological outcomes, a large percentage of elderly patients with CRLM are undertreated.

Perioperative chemotherapy versus surgery alone for resectable colorectal liver metastases: an international multicentre propensity score matched analysis on long-term outcomes according to established prognostic risk scores

BACKGROUND

There is still uncertainty regarding the role of perioperative chemotherapy (CTx) in patients with resectable colorectal liver metastases (CRLM), especially in those with a low-risk of recurrence.

METHODS

Multicentre retrospective analysis of patients with CRLM undergoing liver resection between 2010-2015. Patients were divided into two groups according to whether they received perioperative CTx or not and were compared using propensity score matching (PSM) analysis. Then, they were stratified according to prognostic risk scores, including: Clinical Risk Score (CRS), Tumour Burden Score (TBS) and Genetic And Morphological Evaluation (GAME) score.

RESULTS

The study included 967 patients with a median follow-up of 68 months. After PSM analysis, patients with perioperative CTx presented prolonged overall survival (OS) in comparison with the surgery alone group (82.8 vs 52.5 months, p = 0.017). On multivariable analysis perioperative CTx was an independent predictor of increased OS (HR 0.705, 95%CI 0.705-0.516, p = 0.029). The benefits of perioperative CTx on survival were confirmed in patients with CRS and TBS scores ≤2 (p = 0.022 and p = 0.020, respectively) and in patients with a GAME score ≤1 (p = 0.006).

CONCLUSION

Perioperative CTx demonstrated an increase in OS in patients with CRLM. Patients with a low-risk of recurrence seem to benefit from systemic treatment.

Analysis of learning styles in a laparoscopic technical skills course. Implications for surgical training

INTRODUCTION

Learning surgical techniques is a dynamic process. In the 1980s David Kolb described developed a learning model that enabled teaching styles to adapt for better learner outcomes. The aim of this study was to identify the Kolb learning styles of the participants in a laparoscopic technical skills course and to check see if there was any relationship with performance.

METHODS

An observational descriptive study was conducted with 64 participants in an intensive course in which they performed laparoscopic manual intestinal anastomoses. All completed Kolb's inventory of learning styles. For each anastomosis, join quality was assessed and the performing time recorded. After that, they were analyzed through statistical studies.

RESULTS

The most frequent learning style was assimilating type (39.1%). No significant differences were observed between different learning styles and gender, professional category, the time taken or the quality of the anastomoses.

CONCLUSIONS

Assimilating type was the most frequent Kolb learning style, with no differences observed between categories, age or gender. There is no relationship between the learning style of the participants and the results obtained in the course.

Sleep deprivation among surgical residents: does it affect performance while practising a laparoscopic intestinal anastomosis?

INTRODUCTION

To assess the impact of fatigue due to incorrect night rest in the performance of a laparoscopic manual anastomosis.

METHODS

A prospective study evaluating the results from the realization of a manual endotrainer entero-enteral anastomosis performed by residents in terms of fatigue caused by inadequate nightly rest. Two groups were established; the fatigue group (F): anastomosis performed by residents coming off shift who slept less than seven hours and the rest group (R), being those who slept at home for more than 7 hours. The time taken, length of the anastomosis and quality of such were compared based on 4 parameters: Air leak test, correct tension on the suture line, accurate opposition of the edges and optimal distance between stitches.

RESULTS

402 anastomoses were studied (211 rest group, 191 fatigue group). In the fatigue group leaks were detected in 33,5% anastomoses, as opposed to 19,4% in the rest group (p < 0.01). El rest group performed the anastomosis in 56,75 min and the fatigue group in 61,49 min (p = 0.006). There were no significant differences in the others parameters.

CONCLUSIONS

Fatigue increases the risk of leakage and the time to do the exercise.

Analysis of learning styles in a laparoscopic technical skills course. Implications for surgical training

INTRODUCTION

Learning surgical techniques is a dynamic process. In the 1980s David Kolb described developed a learning model that enabled teaching styles to adapt for better learner outcomes. The aim of this study was to identify the Kolb learning styles of the participants in a laparoscopic technical skills course and to check see if there was any relationship with performance.

METHODS

An observational descriptive study was conducted with 64 participants in an intensive course in which they performed laparoscopic manual intestinal anastomoses. All completed Kolb's inventory of learning styles. For each anastomosis, join quality was assessed and the performing time recorded. After that, they were analyzed through statistical studies.

RESULTS

The most frequent learning style was assimilating type (39.1%). No significant differences were observed between different learning styles and gender, professional category, the time taken or the quality of the anastomoses.

CONCLUSIONS

Assimilating type was the most frequent Kolb learning style, with no differences observed between categories, age or gender. There is no relationship between the learning style of the participants and the results obtained in the course.

Is Routine Prophylaxis Against Pneumocystis jirovecii Needed in Liver Transplantation? A Retrospective Single-Centre Experience and Current Prophylaxis Strategies in Spain

In liver transplant (LT) recipients, Pneumocystis jirovecii pneumonia (PJP) is most frequently reported before 1992 when immunosuppressive regimens were more intense. It is uncertain whether universal PJP prophylaxis is still applicable in the contemporary LT setting. We aimed to examine the incidence of PJP in LT recipients followed at our institution where routine prophylaxis has never been practiced and to define the prophylaxis strategies currently employed among LT units in Spain. All LT performed from 1990 to October 2019 were retrospectively reviewed and Spanish LT units were queried via email to specify their current prophylaxis strategy. During the study period, 662 LT procedures were carried out on 610 patients. Five cases of PJP were identified, with only one occurring within the first 6 months. The cumulative incidence and incidence rate were 0.82% and 0.99 cases per 1000 person transplant years. All LT units responded, the majority of which provide prophylaxis (80%). Duration of prophylaxis, however, varied significantly. The low incidence of PJP in our unprophylaxed cohort, with most cases occurring beyond the usual recommended period of prophylaxis, questions a one-size-fits-all approach to PJP prophylaxis. A significant heterogeneity in prophylaxis strategies exists among Spanish LT centres.

Influence of previous experience on the benefits of laparoscopic surgical training based on simulation

INTRODUCTION

Surgical training based on simulation seeks the acquisition of skills in novice participants and ongoing sill development in experts. The aim of this study is to assess the evolution of students in an intensive laparoscopic anastomosis course and to analyse their results depending on their level and previous experience.

METHODS

The students of all the anastomosis courses conducted during 30 months in the Valdecilla virtual hospital (Santander) were analysed. Manual side-to-side intestinal anastomoses with porcine 'ex vivo' viscera were performed in a laparoscopic endotrainer. The technical and quality differences between the first and the last anastomoses were analyzed and the progression between residents and specialists was compared.

RESULTS

We analyzed 45 participants, 22 of them residents and 23 specialists. A statistically significant improvement of 80.5% was observed in all procedural parameters (94.8% residents vs. 67.3% specialists). The time was reduced by 48.1% in the residents and 43.2% in the specialists (p<.001). In terms of quality, significant improvements were obtained in the group of residents: an increase of 90% in adequate tension, and a reduction of 75% of everted edges and 60% of leaks. In addition, they obtained results comparable to the specialists (27.3% leak in the last anastomosis vs. 34.8% by the specialists, p=.59), which presented improvement without statistical significance.

CONCLUSIONS

The group of residents presented a major and significant improvement in procedural skills and in the quality of the technique, reaching the level of the specialists after completion of the course.