Higher risk of incomplete mesorectal excision and positive circumferential margin in low rectal cancer regardless of surgical technique

From Dukes-MAC Staging System to Molecular Classification: Evolving Concepts in Colorectal Cancer

This historical review aimed to summarize the main changes that colorectal carcinoma (CRC) staging systems suffered over time, starting from the creation of the classical Duke’s classification, modified Astler–Coller staging, internationally used TNM (T—primary tumor, N—regional lymph nodes’ status, M—distant metastases) staging system, and ending with molecular classifications and epithelial–mesenchymal transition (EMT) concept. Besides currently used staging parameters, this paper briefly presents the author’s contribution in creating an immunohistochemical (IHC)-based molecular classification of CRC. It refers to the identification of three molecular groups of CRCs (epithelial, mesenchymal and hybrid) based on the IHC markers E-cadherin, β-catenin, maspin, and vimentin. Maspin is a novel IHC antibody helpful for tumor budding assessment, which role depends on its subcellular localization (cytoplasm vs. nuclei). The long road of updating the staging criteria for CRC has not come to an end. The newest prognostic biomarkers, aimed to be included in the molecular classifications, exert predictive roles, and become more and more important for targeted therapy decisions.

The feasibility and technical strategy of a fascia space priority approach in laparoscopic lateral lymph node dissection for advanced middle and low rectal cancer: a retrospective multicentre study

Introduction

Laparoscopic lateral lymph node dissection (LLND) is an important treatment for patients with lateral lymph node metastasis.

Aim

To assess the technical feasibility and investigate the surgical outcomes after LLND using the fascia space priority approach for patients with advanced middle and low rectal cancer.

Material and methods

Consecutive patients undergoing laparoscopic LLND using the fascia space priority approach from June 2017 to June 2020 were identified from 12 medical centres in mainland China. Three anatomic fascia spaces were dissected to establish the boundaries of the LLND, and the obturator and internal iliac lymph nodes were excised in an en bloc manner. Retrospective clinical data including patient characteristics, surgical details, and pathology were analysed.

Results

A total of 112 patients were identified. All surgeries were completed laparoscopically with no conversions. The mean operation time was 343.6 ±103.8 min for the entire procedure. The median blood loss was 100 ml (range: 100-700 ml). The median lymph node yield was 6 (range: 1-41), and lymph nodes were positive in 39.3% (44/112) of the patients. Sixteen (14.3%) patients had Clavien-Dindo I-II complications, no Clavien-Dindo III-IV complications were identified. The incidence of complications between the bilateral dissection group and the unilateral dissection group was not statistically different (p = 0.19). The complication rate between the "nCRT" group and the "no nCRT" group was not significantly different (p = 0.62) either. There were no perioperative deaths.

Conclusions

Laparoscopic LLND using the fascia space priority approach is feasible and safe for patients with lateral lymph node metastasis.

Risk factors for suboptimal laparoscopic surgery in rectal cancer patients

PURPOSE

Laparoscopic surgery for rectal cancer is technically complex. This study aimed to identify risk factors for suboptimal laparoscopic surgery (involved margins, incomplete mesorectal excision, and/or conversion to open surgery) in patients with rectal cancer.

METHODS

We included patients undergoing laparoscopic anterior resection for rectal cancer between June 2009 and June 2018. We defined the outcome variable suboptimal laparoscopic surgery as conversion to open surgery or inadequate histopathological specimens (margins < 1 mm or involved and/or poor-quality mesorectal excision). To identify independent predictors of suboptimal laparoscopic surgery, we analyzed 15 prospectively recorded demographic, clinical, and anthropometric variables obtained from our rectal cancer unit's database. Subanalyses examined the same variables with respect to conversion and to inadequate histopathological specimens.

RESULTS

Of the 323 patients included, 91 (28.2%) had suboptimal laparoscopic surgery. In the multivariate analysis, the independent factors associated with all suboptimal laparoscopic surgery were tumor location ≤ 5 cm from the anal verge (OR = 2.95, 0.95% CI 1.32-6.60; p = 0.008) and the intertuberous distance (OR = 0.79, 0.95% CI 0.65-0.96; p = 0.019). In the subanalyses, the promontorium-retropubic axis was an independent predictor of conversion (OR 0.70, 0.95% CI 0.51-0.96; p = 0.026), and tumor location ≤ 5 cm from the anal verge (OR 3.71, 0.95% 1.51-9.15; p = 0.004) was an independent predictor of inadequate histopathological specimens.

CONCLUSIONS

Predictive factors for suboptimal laparoscopic anterior resection for rectal cancer were tumor location and the intertuberous distance. These results could help surgeons decide whether to use other surgical approaches in complex cases.

TRIAL REGISTRATION

The study was registered at Clinicaltrials.org (No. NCT03107650).

Surgical resection for rectal cancer. Is laparoscopic surgery as successful as open approach? A systematic review with meta-analysis

BACKGROUND

Recently, it has been questioned if minimally invasive surgery for rectal cancer was surgically successful. We decided to perform a meta-analysis to determine if minimally invasive surgery is adequate to obtain a complete resection for curable rectal cancer.

METHODS

A systematic search pertaining to evaluation between laparoscopic and open rectal resection for rectal cancer was performed until 30th November 2016 in the electronic databases (PubMed, Web of Science, Scopus, EMBASE), using the following search terms in all possible combinations: rectal cancer, laparoscopy, minimally invasive and open surgery. Outcomes analyzed were number of clear Distal Resection Margins (DRM or DM), complete Circumferential Resection Margins (CRM) and complete, nearly complete and incomplete Total Mesorectal Excision (TME) and of patients who received laparoscopic or open treatment for rectal cancer.

RESULTS

12 articles were included in the final analysis. The prevalence of successful surgical resection was similar between open and laparoscopic surgery. About distance from distal margin of the specimen, clear CRM and complete TME there were no statistically significant difference between the two groups (MD = -0.090 cm, p = 0.364, 95% CI -0.283, 0.104; OR = 1.032, p = 0.821, 95% CI 0.784, 1.360; OR = 0.933, p = 0.720, 95% CI 0.638, 1.364, respectively). The analysis of nearly complete TME showed a significant difference between the two groups (OR = 1.407, p = 0.006, 95% CI 1.103, 1.795), while the analysis of incomplete TME showed a non-significant difference (OR = 1.010, p = 0.964, 95% CI 0.664, 1.534).

CONCLUSIONS

By pooling together data from 5 RCTs and 7 nRCTs, we are able to provide evidence of safety and efficacy of minimally invasive surgery. Waiting for further randomized clinical trials, our results are encouraging to introduce laparoscopic rectal resection in daily practice.

Transanal total mesorectal excision (TATME) - preliminary findings

Fifteen years ago, laparoscopic surgery of rectal cancer was considered as radical in terms of oncology as open surgery. A trend to reduce surgical injury may be observed in surgery in recent years. In this paper the first experience in the new minimally invasive method of anterior rectal resection is described - through the transanal way. The procedure duration was 130 min. The use of transanal access in rectal cancer surgery is undoubtedly an alternative method to standard laparoscopic surgery. In patients with a large tumour in the lower rectum, the technique allows a longer rectal stump to be left below the resection border.