Quality assessment of surgery for colorectal cancer: Where do we stand?

Quality assurance in surgery has been one of the most important topics of debate among colorectal surgeons in the past decade. It has produced new surgical standards that led in part to the impressive oncological outcomes we see in many units today. Total mesorectal excision, complete mesocolic excision (CME), and the Japanese D3 lymphadenectomy are now benchmark techniques embraced by many surgeons and widely recommended by surgical societies. However, there are still ongoing discrepancies in outcomes largely based on surgeon performance. This is one of the main reasons why many countries have shifted colorectal cancer surgery only to high volume centers. Defining markers of surgical quality is thus a perquisite to ensure that standards and oncological outcomes are met at an institutional level. With the evolution of CME surgery, various quality markers have been described, mostly based on measurements on the surgical specimen and lymph node yield, while others have proposed radiological markers (i.e. arterial stumps) measured on postoperative scans as part of the routine cancer follow-up. There is no ideal marker; however, taken together and assembled into a new score or set of criteria may become a future point of reference for reporting outcomes of colorectal cancer surgery in research studies and defining subspecialization requirements both at an individual and hospital level.

The mesocolic apical fragment in complete mesocolic excision colectomies: Should it be analysed separately? A proof-of-concept study.

AIM: The aim of this work is to describe a protocol and assess the feasibility of harvesting and analysing the mesocolic apical fragment (MAF) for the presence of central lymph node (LN) metastasis and extra lymphatic free tumour cells in a random subgroup extracted from a cohort of complete mesocolic excision colectomies with central vascular ligation. METHOD: Forty-seven patients diagnosed with colorectal cancer were included. A 2/2 cm pyramid of tissue was cut around the central tie and sent for pathological examination. The MAF was sectioned into 16 slices. High-definition images were taken from the slices which were merged into a panoramic three-dimensional image of the MAF. The distribution of LNs in the MAF was quantified. Immunohistochemistry staining for cytokeratin 14 was used to identify isolated tumour cells and micrometastases in the extranodal tissue. RESULTS: No tumoural cells migrating through the apical zone, outside of the LNs, were identified. Margins of resection, mesocolic tissue and LNs were all negative in the subgroup of ultrastaged MAFs. The number of examined central LNs varied between 0 and 24, with positive MAF LNs being identified only in pN2 stages. The rate of positive apical LNs in our cohort was 4.2% (n = 2). CONCLUSIONS: The MAF can be easily extracted from standard specimens, allowing for accurate analysis of lymphatic and extra-nodal tumour cells on the central resection margins, in central LNs and in the apical mesocolic tissue. Future research on larger cohorts is required to establish if analysing the MAF has an impact on patient staging, prognosis and management.

Postoperative Quality Assessment Score Can Select Patients with High Risk for Locoregional Recurrence in Colon Cancer.

BACKGROUND: Monitoring surgical quality has been shown to reduce locoregional recurrence (LRR). We previously showed that the arterial stump length (ASL) after complete mesocolic excision (CME) is a reproducible quality instrument and correlates with the lymph-node (LN) yield. We hypothesized that generating an LRR prediction score by integrating the ASL would predict the risk of LRR after suboptimal surgery. METHODS: 502 patients with curative resections for stage I-III colon cancer were divided in two groups (CME vs. non-CME) and compared in terms of surgical data, ASL-derived parameters, pathological parameters, LRR and LRR-free survival. A prediction score was generated to stratify patients at high risk for LRR. RESULTS: The ASL showed significantly higher values (50.77 mm ± 28.5 mm) with LRR vs. (45.59 mm ± 28.1 mm) without LRR (p < 0.001). Kaplan-Meier survival analysis showed a significant increase in LRR-free survival at 5.58 years when CME was performed (Group A: 81%), in contrast to non-CME surgery (Group B: 67.2%). CONCLUSIONS: The prediction score placed 76.6% of patients with LRR in the high-risk category, with a strong predictive value. Patients with long vascular stumps and positive nodes could benefit from second surgery to complete the mesocolic excision.

The Use of Mucolytic Agent in Percutaneous Drainage of Liver Abscess: A Case-Series Analysis.

Background: Liver abscess is a scarce but potentially fatal suppurative process. There is a general tendency for minimally invasive treatment, such as broad-spectrum antibiotherapy and percutaneous drainage. Multiloculated, multiple or incompletely liquefied abscesses often limit the efficacy of percutaneous drainage. This study aims to assess the effectiveness of percutaneous drainage and intracavitary instillation of a mucolytic agent for liver abscesses. Material and method: From our department database, we have identified patients with liver abscess admitted during the period 2015 - 2020, treated by ultrasound-guided percutaneous drainage and intracavitary instillation of mucolytic agent. Data regarding imaging appearance, drainage technique, inflammatory markers and clinical course were assessed. Results: Twenty-one patients with multiloculated liver abscesses, sized 8 to 17 cm, were percutaneously drained, with local anaesthesia, under ultrasound guidance. The bacteriological exam of the aspirate showed bacterial infection in 19 cases, mostly Klebsiella pneumoniae, and 2 fungal infections. Acetylcysteine in dilution 1: 1 with saline was instilled daily on the 12F or 14 F drainage catheter. Clinical and radiological resolution was achieved within 14 to 29 days. Two cases required supplementary drainage of a non-communicating residual cavity. There were no complications, periprocedural deaths or relapse at 3 months follow-up. Conclusions: Percutaneous drainage is effective even in the management of multiloculated liver abscesses, facilitated by the use of intracavitary mucolytic agent.

Post-operative computed tomography scan - reliable tool for quality assessment of complete mesocolic excision.

BACKGROUND: Quality control in colon cancer surgery is an ongoing debate ever since standardization proved to be highly efficient in improving survival in rectal cancer. Complete mesocolic excision (CME) is widely acclaimed as the new gold-standard in colon cancer resections, thus it is imperative to establish quality criteria of CME in order to make it easily understood and verified by surgeons worldwide. One simple and reproducible tool could be the measurement of arterial stumps postoperatively and a straightforward way to test its reliability is to test it in a comparative study between CME and non-CME surgery. AIM: To validate arterial stump measurement as a surgical quality tool by comparing CME with conventional radical colectomies. METHODS: This was a retrospective study, carried out on a prospective database. We collected data from two groups of patients, divided according to standard CME with D2 central vascular ligation (group A) and non-standardized surgery (group B). The two groups were compared with regard to the arterial stump length after right- and left-sided colectomies for colon cancer. The actual stump lengths of the ileocolic artery (ICA) and inferior mesenteric artery (IMA) were compared with their theoretical best D2 position of predicted ligation levels (D2PLLs) for calculating the potential for improvement. Measurements on follow-up computed tomography scans were carried out by three observers. Pathological data were recorded (specimen length, lymph node yield) and correlated with stump length. RESULTS: We analysed 58 colectomies. The stump lengths (mean ± SD) in group A were 16.97 ± 4.77 mm for ICA and 31.70 ± 15.71 mm for IMA, whereas group B had 49.93 ± 20.29 mm for ICA and 67.24 ± 28.71 mm for IMA. Shorter lengths were obtained in group A, by a mean difference of 35.66 mm (χ 2 = 27.38, P < 0.001), which was significant for all types of colectomies. Except for a 5.85 ± 4.71 mm difference for right colectomies, all the ligations from group A significantly reached their potential height (0.26 ± 12.18 mm from D2PLL; χ 2 = 0.005, P = 0.944). Apart from three left colectomies, group B failed to reach D2PLL, by a mean difference of 32.14 ± 26.15 mm (χ 2 = 21.77, P < 0.001). The calculated improvement potentials were significantly shorter in group A than in group B, by a mean of 31.88 mm (χ 2 = 22.13, P < 0.001). The large spread of results in group B showed that there is significant variability (P = 0.004) when compared to standard surgery. Significant correlations were found between stump length, specimen length and number of lymph nodes (P = 0.018 and P = 0.008 respectively). No statistical difference was found between observers' measurements (P = 0.866). CONCLUSION: Arterial stump monitoring is a significant step in defining surgical quality, as longer stumps contain residual mesocolic tissue and correlate with major prognostic factors.