Accuracy of CT colonography in the preoperative staging of colon cancer: a prospective study of 217 patients

AIM

The purpose of the present study was to evaluate the accuracy of computed tomography colonography (CTC) in the preoperative localization and TN staging of colon cancer. CTC can be an effective technique for preoperative evaluation of colon cancer and could facilitate the selection of high-risk patients who may benefit from neoadjuvant chemotherapy.

METHOD

This was a prospective observational study conducted at a single tertiary-care centre. It involved 217 patients (225 tumours) who had colon cancer and underwent preoperative CTC and elective colectomy. The radiologist determined the TNM stage using postprocessing software with multiplanar images and virtual colonoscopy. The following criteria were analysed for every colon tumour: location, size and signs of direct colon wall invasion. The histopathological findings of the surgical colectomy specimens served as the reference standard for local staging.

RESULTS

CTC detected all tumours and achieved an exact location in 208 cases (92.4%). CTC findings changed the surgical plan in 31 patients (14.3%) following colonoscopy. The accuracy in differentiating T3/T4 vs T1/T2 tumours was 87.1%, with a sensitivity and specificity of 88.5% and 84.1%, respectively (kappa = 0.71). For high-risk tumours (T3 ≥ 5 mm and T4), CTC showed an accuracy, sensitivity and specificity of 82.7%, 86% and 80%, respectively (kappa = 0.65). The accuracy of N-stage evaluation was 69.3%, the sensitivity 74% and the specificity 67.1% (kappa = 0.37).

CONCLUSION

CTC provides accurate information for the assessment of tumour localization and T staging, allowing better surgical planning and also allows the selection of locally advanced tumours that may benefit from new treatments such as neoadjuvant chemotherapy.

The fusion fascia of Fredet: an important embryological landmark for complete mesocolic excision and D3-lymphadenectomy in right colon cancer

BACKGROUND

The fusion fascia of Toldt is a well-known landmark used by colorectal surgeons. On the contrary, the fusion fascia of Fredet (the plane between the ascending mesocolon and the visceral duodenal-pancreatic peritoneum) still remains a neglected embryological structure. Aim of this study was to provide an anatomic description of this fascia and its application to minimally invasive D3-lymphadenectomy (D3-L) and complete mesocolic excision (CME) for right colon cancer.

METHODS

First phase: Cadaveric dissection and anatomic description of the fascia of Fredet. Second phase: prospective evaluation of its surgical application in a consecutive series of laparoscopic right hemicolectomies with CME and D3-L at a tertiary hospital.

RESULTS

The fascia of Fredet was identified and dissected in one fresh and two formalin-fixed cadavers. The trunk of Henle and the medial border of the superior mesenteric vein defined the medial limit of this embryologic plane. Seventeen patients were operated on. Laparoscopic dissection of the fascia of Fredet was possible in every patient. Median operative time was 210 (120-380) min. There were no major postoperative complications. All cases were adenocarcinomas, except one adenomatous polyp. T stage was Tis in three, T2 in two, T3 in seven, and T4 in five patients. Median number of harvested lymph nodes was 24 (9-39). Lymphatic invasion was found in six patients. All resections were classified as satisfactory mesocolic excision and R0. Median postoperative length of stay was 6 (4-20) days. Median follow-up time was 28 (16-41) months. Local and distal recurrence rate was 0.

CONCLUSION

The fusion fascia of Fredet is useful to achieve CME and D3-L in right colon cancers with reduced risk of intraoperative complications. This structure is particularly suitable for minimally invasive surgery; therefore, we encourage awareness of the fascia of Fredet by colorectal surgeons.

A multifaceted individualized pneumoperitoneum strategy for laparoscopic colorectal surgery: a multicenter observational feasibility study

BACKGROUND

While guidelines for laparoscopic abdominal surgery advise using the lowest possible intra-abdominal pressure, commonly a standard pressure is used. We evaluated the feasibility of a predefined multifaceted individualized pneumoperitoneum strategy aiming at the lowest possible intra-abdominal pressure during laparoscopic colorectal surgery.

METHODS

Multicenter prospective study in patients scheduled for laparoscopic colorectal surgery. The strategy consisted of ventilation with low tidal volume, a modified lithotomy position, deep neuromuscular blockade, pre-stretching of the abdominal wall, and individualized intra-abdominal pressure titration; the effect was blindly evaluated by the surgeon. The primary endpoint was the proportion of surgical procedures completed at each individualized intra-abdominal pressure level. Secondary endpoints were the respiratory system driving pressure, and the estimated volume of insufflated CO₂ gas needed to perform the surgical procedure.

RESULTS

Ninety-two patients were enrolled in the study. Fourteen cases were converted to open surgery for reasons not related to the strategy. The intervention was feasible in all patients and well-accepted by all surgeons. In 61 out of 78 patients (78%), surgery was performed and completed at the lowest possible IAP, 8 mmHg. In 17 patients, IAP was raised up to 12 mmHg. The relationship between IAP and driving pressure was almost linear. The mean estimated intra-abdominal CO₂ volume at which surgery was performed was 3.2 L.

CONCLUSION

A multifaceted individualized pneumoperitoneum strategy during laparoscopic colorectal surgery was feasible and resulted in an adequate working space in most patients at lower intra-abdominal pressure and lower respiratory driving pressure. ClinicalTrials.gov (Trial Identifier: NCT03000465).

Predictors of complications and mortality following left colectomy with primary stapled anastomosis for cancer: results of a multicentric study with 1111 patients

AIM

Reports detailing the morbidity-mortality after left colectomy are sparse and do not allow definitive conclusions to be drawn. We aimed to identify risk factors for anastomotic leakage, perioperative mortality and complications following left colectomy for colonic malignancies.

METHOD

We undertook a STROBE-compliant analysis of left colectomies included in a national prospective online database. Forty-two variables were analysed as potential independent risk factors for anastomotic leakage, postoperative morbidity and mortality. Variables were selected using the 'least absolute shrinkage and selection operator' (LASSO) method.

RESULTS

We analysed 1111 patients. Eight per cent of patients had a leakage and in 80% of them reoperation or surgical drainage was needed. A quarter of patients (24.9%) experienced at least one minor complication. Perioperative mortality was 2%, leakage being responsible for 47.6% of deaths. Obesity (OR 2.8, 95% CI 1.00-7.05, P = 0.04) and total parenteral nutrition (TPN) (OR 3.7, 95% CI 1.58-8.51, P = 0.002) were associated with increased risk of leakage, whereas female patients had a lower risk (OR 0.36, 95% CI 0.18-0.67, P = 0.002). Corticosteroids (P = 0.03) and oral anticoagulants (P = 0.01) doubled the risk of complications, which was lower with hyperlipidaemia (OR 0.3, P = 0.02). Patients on TPN had more complications (OR 4.02, 95% CI 2.03-8.07, P = 0.04) and higher mortality (OR 8.7, 95% CI 1.8-40.9, P = 0.006). Liver disease and advanced age impaired survival, corticosteroids being the strongest predictor of mortality (OR 21.5, P = 0.001).

CONCLUSION

Requirement for TPN was associated with more leaks, complications and mortality. Leakage was presumably responsible for almost half of deaths. Hyperlipidaemia and female gender were associated with lower rates of complications. These findings warrant a better understanding of metabolic status on perioperative outcome after left colectomy.

How to reduce the superior mesenteric vein bleeding risk during laparoscopic right hemicolectomy

PURPOSE

The superior right colic vein (SRCV) has been proposed as the main cause of superior mesenteric vein bleeding by avulsion during laparoscopic right hemicolectomy. Our objective is to identify the main vessel causing transverse mesocolic tension during the extraction of the surgical specimen or extracorporeal anastomosis and to perform an anatomical description of the SRCV.

METHODS

In this cadaveric study, we performed a simulation of right hemicolectomy and anatomical description of the surgical area of the gastrocolic trunk of Henle (SAGCTH), the gastrocolic trunk of Henle (GCTH), and SRCV. The length of the exteriorization of the anastomotic transverse colon (ATC) was measured before and after sectioning the vascular vessel causing the exteriorization tension.

RESULTS

Five fresh cadavers and 12 formalin were dissected. In 100% of the specimens, the SRCV was present and drained in 95% into the GCTH and in 5% directly into the superior mesenteric vein (SMV). In 100% of the specimens, the SRCV caused the tension when extracting the ATC. The mean length of exteriorization of the ATC before and after SRCV section was 7.2 and 10.4 cm in formalin cadavers, meaning a 44% of increment in the length of exteriorization. In fresh cadavers, the mean length of exteriorization increased to 2.7 cm, meaning a 28% of the initial length of exteriorization.

CONCLUSIONS

The SRCV is the main cause of tension in the extraction of the surgical specimen after right hemicolectomy. Its high tie increases the length of the ATC exteriorization, in about 3 cm, and could reduce the risk of SMV bleeding during laparoscopic right hemicolectomy and facilitate an extracorporeal anastomosis free of tension.

Integrating Downstaging in the Risk Assessment of Patients With Locally Advanced Rectal Cancer Treated With Neoadjuvant Chemoradiotherapy: Validation of Valentini's Nomograms and the Neoadjuvant Rectal Score

BACKGROUND

Adjuvant chemotherapy is controversial in patients with locally advanced rectal cancer after preoperative chemoradiation. Valentini et al developed 3 nomograms (VN) to predict outcomes in these patients. The neoadjuvant rectal score (NAR) was developed after VN to predict survival. We aimed to validate these tools in a retrospective cohort at an academic institution.

PATIENTS AND METHODS

VN and the NAR were applied to 158 consecutive patients with locally advanced rectal cancer treated with chemoradiation followed by surgery. According to the score, they were divided into low, intermediate, or high risk of relapse or death. For statistical analysis, we performed Kaplan-Meier curves, log-rank tests, and Cox regression analysis.

RESULTS

Five-year overall survival was 83%, 77%, and 67% for low-, intermediate-, and high-risk groups, respectively (P = .023), according to VN, and 84%, 71%, and 59% for low-, intermediate-, and high-risk groups, respectively (P = .004), according to NAR. When the score was considered as a continuous variable, a significant association with the risk of death was observed (NAR: hazard ratio, 1.04; P < .001; VN: hazard ratio, 1.10; P < .001).

CONCLUSION

We confirmed the value of these scores to stratify patients according to their individual risk when designing new trials.

Individual surgeon is an independent risk factor for leak after double-stapled colorectal anastomosis: An institutional analysis of 800 patients

BACKGROUND

Our aim was to assess whether the individual surgeon is an independent risk factor for anastomotic leak in double-stapled colorectal anastomosis after left colon and rectal cancer resection.

METHODS

This retrospective analysis of a prospectively collected database consists of a consecutive series of 800 patients who underwent an elective left colon and rectal resection with a colorectal, double-stapled anastomosis between 1993 and 2009 in a specialized colorectal unit of a tertiary hospital with 7 participating surgeons. The main outcome variable was anastomotic leak, defined as leak of luminal contents from a colorectal anastomosis between 2 hollow viscera diagnosed radiologically, clinically, endoscopically, or intraoperatively. Pelvic abscesses were also considered to be an anastomotic leak. Radiologic examination was performed when there was clinical suspicion of leak.

RESULTS

Anastomotic leak occurred in 6.1% of patients, of which 33 (67%) were treated operatively, 6 (12%) with radiologic drains, and 10 (21%) by medical treatment. Postoperative mortality rate was 2.9% for the whole group of 800 patients. In patients with anastomotic leak, mortality rate increased up to 16% vs 2.0% in patients without anastomotic leak (P < .0001). At multivariate analysis, rectal location of tumor, male sex, bowel obstruction preoperatively, tobacco use, diabetes, perioperative transfusion, and the individual surgeon were independent risk factors for anastomotic leak. The surgeon was the most important factor (mean odds ratio 4.9; range 1.0 to 13.5). The variance of anastomotic leak between the different surgeons was 0.56 in the logit scale.

CONCLUSION

The individual surgeon is an independent risk factor for leakage in double-stapled, colorectal, end-to-end anastomosis after oncologic left-sided colorectal resection.

Accuracy of magnetic resonance enterography in the preoperative assessment of patients with Crohn's disease of the small bowel

AIM

To assess the accuracy of magnetic resonance enterography in predicting the extension, location and characteristics of the small bowel segments affected by Crohn's disease.

METHOD

This is a prospective study including a consecutive series of 38 patients with Crohn's disease of the small bowel who underwent surgery at a specialized colorectal unit of a tertiary hospital. Preoperative magnetic resonance enterography was performed in all patients, following a homogeneous protocol, within the 3 months prior to surgery. A thorough exploration of the small bowel was performed during the surgical procedure; calibration spheres were used according to the discretion of the surgeon. The accuracy of magnetic resonance enterography in detecting areas affected by Crohn's disease in the small bowel was assessed. The findings of magnetic resonance enterography were compared with surgical and pathological findings.

RESULTS

Thirty-eight patients with 81 lesions were included in the study. During surgery, 12 lesions (14.8%) that were not described on magnetic resonance enterography were found. Seven of these were detected exclusively by the use of calibration spheres, passing unnoticed at surgical exploration. Magnetic resonance enterography had 90% accuracy in detecting the location of the stenosis (75.0% sensitivity, 95.7% specificity). Magnetic resonance enterography did not precisely diagnose the presence of an inflammatory phlegmon (accuracy 46.2%), but it was more accurate in detecting abscesses or fistulas (accuracy 89.9% and 98.6%, respectively).

CONCLUSION

Magnetic resonance enterography is a useful tool in the preoperative assessment of patients with Crohn's disease. However, a thorough intra-operative exploration of the entire small bowel is still necessary.

Laparoscopy may decrease morbidity and length of stay after elective colon cancer resection, especially in frail patients: results from an observational real-life study

BACKGROUND

Advantages of laparoscopic approach in colon cancer surgery have been previously demonstrated in controlled, randomized trials and in retrospective analysis of large administrative databases. Nevertheless, evidence of these advantages in prospective, observational studies from real-life settings is scarce.

METHODS

This is a prospective, observational study, including a consecutive series of patients that underwent elective colonic resection for cancer in 52 Spanish hospitals. Pre-/intraoperative data, related to patient, tumor, surgical procedure, and hospital, were recorded as well as 60-day post-operative outcomes, including wound infection, complications, anastomotic leak, length of stay, and mortality. A univariate and multivariate analysis was performed to determine the influence of laparoscopy on short-term post-operative outcome. A sub-analysis of the effect of laparoscopy according to patients' pre-operative risk (ASA Score I-II vs. III-IV) was also performed.

RESULTS

2968 patients were included: 44.2% were initially operated by laparoscopy, with a 13.9% conversion rate to laparotomy. At univariate analysis, laparoscopy was associated with a decreased mortality (p = 0.015), morbidity (p < 0.0001), wound infection (p < 0.0001), and post-operative length of stay (p < 0.0001). At multivariate analysis, laparoscopy resulted as an independent protective factor for morbidity (OR 0.7; p = 0.004), wound infection (OR 0.6; p < 0.0001), and length of post-operative stay (Effect-2 days; p < 0.0001), compared to open approach. These advantages were more relevant in high-risk patients (ASA III-IV), even if the majority of them were operated by open approach (67.1%).

CONCLUSIONS

In a real-life setting, laparoscopy decreases wound infection rate, post-operative complications, and length of stay, especially in ASA III-IV patients.

Efficacy of hydrodynamic interleukin 10 gene transfer in human liver segments with interest in transplantation

Different diseases lead, during their advanced stages, to chronic or acute liver failure, whose unique treatment consists in organ transplantation. The success of intervention is limited by host immune response and graft rejection. The use of immunosuppressant drugs generally improve organ transplantation, but they cannot completely solve the problem. Also, their management is delicate, especially during the early stages of treatment. Thus, new tools to set an efficient modulation of immune response are required. The local expression of interleukin (IL) 10 protein in transplanted livers mediated by hydrodynamic gene transfer could improve the organ acceptance by the host because it presents the natural ability to modulate the immune response at different levels. In the organ transplantation scenario, IL10 has already demonstrated positive effects on graft tolerance. Hydrodynamic gene transfer has been proven to be safe and therapeutically efficient in animal models and could be easily moved to the clinic. In the present work, we evaluated efficacy of human IL10 gene transfer in human liver segments and the tissue natural barriers for gene entry into the cell, employing gold nanoparticles. In conclusion, the present work shows for the first time that hydrodynamic IL10 gene transfer to human liver segments ex vivo efficiently delivers a human gene into the cells. Indexes of tissue protein expression achieved could mediate local pharmacological effects with interest in controlling the immune response triggered after liver transplantation. On the other hand, the ultrastructural study suggests that the solubilized plasmid could access the hepatocyte in a passive manner mediated by the hydric flow and that an active mechanism of transportation could facilitate its entry into the nucleus. Liver Transplantation 23:50-62 2017 AASLD.