Surgical resection of colorectal carcinoma metastases to the liver. A prognostic scoring system to improve case selection, based on 1568 patients. Association Française de Chirurgie

Colorectal liver metastases patients prognostic assessment: prospects and limits of radiomics and radiogenomics

In this narrative review, we reported un up-to-date on the role of radiomics to assess prognostic features, which can impact on the liver metastases patient treatment choice. In the liver metastases patients, the possibility to assess mutational status (RAS or MSI), the tumor growth pattern and the histological subtype (NOS or mucinous) allows a better treatment selection to avoid unnecessary therapies. However, today, the detection of these features require an invasive approach. Recently, radiomics analysis application has improved rapidly, with a consequent growing interest in the oncological field. Radiomics analysis allows the textural characteristics assessment, which are correlated to biological data. This approach is captivating since it should allow to extract biological data from the radiological images, without invasive approach, so that to reduce costs and time, avoiding any risk for the patients. Several studies showed the ability of Radiomics to identify mutational status, tumor growth pattern and histological type in colorectal liver metastases. Although, radiomics analysis in a non-invasive and repeatable way, however features as the poor standardization and generalization of clinical studies results limit the translation of this analysis into clinical practice. Clear limits are data-quality control, reproducibility, repeatability, generalizability of results, and issues related to model overfitting.

Outcomes of staged hepatectomies for liver malignancy

Liver malignancies are the fifth most common cause of death worldwide. Surgical intervention with curative intent is the treatment of choice for liver tumors as it provides long-term survival. However, only 20% of patients with metastatic liver lesions can be managed by curative liver resection. In most of the cases, hepatectomy is not feasible because of insufficient future liver remnant (FLR). Two-stage hepatectomy is advocated to achieve liver resection in a patient who is considered to not be a candidate for resection. Procedures of staged hepatectomy include conventional two-stage hepatectomy, portal vein embolization, and associating liver partition and portal vein ligation for a staged hepatectomy. Technical success is high for each of these procedures but variable between them. All the procedures have been reported as being effective in achieving a satisfactory FLR and completing the second-stage resection. Moreover, the overall survival and disease-free survival rates have improved significantly for patients who were otherwise considered nonresectable; yet, an increase in the morbidity and mortality rates has been observed. We suggest that this type of procedure should be carried out in high-flow centers and through a multidisciplinary approach. An experienced surgeon is key to the success of those interventions.

Colorectal cancer: Metastases to a single organ

Colorectal cancer (CRC) is a common malignancy worldwide. In CRC patients, metastases are the main cause of cancer-related mortality. In a group of metastatic CRC patients, the metastases are limited to a single site (solitary organ); the liver and lungs are the most commonly involved sites. When metastatic disease is limited to the liver and/or lungs, the resectability of the metastatic lesions will dictate the management approach and the outcome. Less commonly, the site of solitary organ CRC metastasis is the peritoneum. In these patients, cytoreduction followed by hyperthermic intraperitoneal chemotherapy may improve the outcome. Rarely, CRC involves other organs, such as the brain, bone, adrenals and spleen, as the only site of metastatic disease. There are limited data to guide clinical practice in these cases. Here, we have reviewed the disease characteristics, management approaches and prognosis based on the metastatic disease site in patients with CRC with metastases to a single organ.

Predictive factors for anastomotic leakage after simultaneous resection of synchronous colorectal liver metastasis

BACKGROUND

The optimal surgical strategy for resectable, synchronous, colorectal liver metastases remains unclear. The objective of this study was to determine which patients could benefit from staged resections instead of simultaneous resection by identifying predictive factors for postoperative morbidity and anastomotic leakage after simultaneous resection of synchronous, colorectal liver metastases and the primary colorectal tumor.

METHODS

This study involved 86 patients with synchronous colorectal liver metastases who underwent simultaneous resection of the primary colorectal tumor and the hepatic tumor. Postoperative mortality, morbidity, and other surgical outcomes, including survival and hospitalization, were assessed. Predictive factors for postoperative morbidity and for anastomotic leakage were evaluated.

RESULTS

Postoperative morbidity and anastomotic leakage were found in 55 (64%) and 18 (21%) patients. Predictive factors for postoperative morbidity and for anastomotic leakage were intraoperative blood loss and operation time >8 h, respectively. The overall 5-year survival rate was 45%.

CONCLUSIONS

The frequency of morbidity and that of anastomotic leakage seemed to be high after simultaneous resection for synchronous colorectal liver metastases, especially when intraoperative blood loss or operation time increased greatly. Staged resections should be considered in cases in which excessive surgical stress from simultaneous resection of synchronous colorectal liver metastases would be expected.

Surveillance of patients following surgery with curative intent for colorectal cancer

Surveillance after resection of colorectal cancer with curative intent is an important component of post-operative care. Clinical review, imaging, colonoscopy, and cost to the community are among significant issues to consider in planning a surveillance regime. This review aims to identify the available evidence for the use of surveillance and its individual components. The literature pertaining to follow-up of patients following potentially curative surgery for colorectal cancer was reviewed in order to formulate a summary of the wide range of clinical practice. There is evidence of improved survival of patients undergoing more intense follow-up compared with those having minimal surveillance, with an estimated overall 5-year gain of up to 10%. The efficacy of individual components of follow-up regimes remains unclear, but an overall package of ‘intensive’ follow-up including clinical review, liver imaging, and colonoscopy appears to be of benefit. It is cost-effective and can be specialist or community-based.

Surgical approaches of resectable synchronous colorectal liver metastases: Timing considerations

AIM: To compare the safety and efficacy of simultaneous versus two stage resection of primary colorectal tumors and liver metastases.

METHODS: From January 1996 to May 2004, 103 colorectal tumor patients presented with synchronous liver metastases. Twenty five underwent simultaneous colorectal and liver surgery and 78 underwent liver surgery 1-3 mo after primary colorectal tumor resection. Data were retrospectively analyzed to assess and compare the morbidity and mortality between the surgical strategies. The two groups were comparable regarding the age and sex distribution, the types of liver resection and stage of primary tumors, as well as the number and size of liver metastases.

RESULTS: In two-stage procedures more transfusions were required (4 ± 1.5 vs 2 ± 1.8, pRBCs, P < 0.05). Chest infection was increased after the two-stage approach (26% vs 17%, P < 0.05). The two-stage procedure was also associated with longer hospitalization (20 ± 8 vs 12 ± 6 d, P < 0.05). Five year survival in both groups was similar (28% vs 31%). No hospital mortality occurred in our series.

CONCLUSION: Synchronous colorectal liver metastases can be safely treated simultaneously with the primary tumor. Liver resection should be prioritized over colon resection. It is advisable that complex liver resections with marginal liver residual volume should be dealt with at a later stage.

Proposal of a new and simple staging system of colorectal liver metastasis

AIM: To create a new, simple and useful staging system for colorectal liver metastasis analogous to the Tumor Node Metastasis classification system of International Union Against Cancer.

METHODS: A retrospective review was undertaken of 81 consecutive patients who underwent partial hepatectomy for colorectal liver metastases (group 1). Clinical and pathological features of both primary and metastatic liver cancers were entered into a multivariate analysis to determine independent variables helpful in accurately predicting long-term prognosis after hepatectomy. Using selected variables, we created a new staging system like TNM classification. The usefulness of the new staging system was examined in a series of 92 patients from another hospital (group 2).

RESULTS: Multivariate analysis showed that 81 patients in group 1 had significant multiple hepatic tumors with the largest tumor being more than 5 cm in diameter, resectable extrahepatic distant metastases, and independent prognostic factors for poor survival after hepatectomy. Using these three variables, we created a new staging system to classify patients with colorectal liver metastases. Finally, our new staging system classified the patients both in group 1 and in group 2.

CONCLUSION: Our new staging system of colorectal liver metastasis is simple and useful for staging patients.

Proposal of criteria to select candidates with colorectal liver metastases for hepatic resection: Comparison of our scoring system to the positive number of risk factors

AIM: To select accurately good candidates of hepatic resection for colorectal liver metastasis.

METHODS: Thirteen clinicopathological features, which were recognized only before or during surgery, were selected retrospectively in 81 consecutive patients in one hospital (GroupI). These features were entered into a multivariate analysis to determine independent and significant variables affecting long-term prognosis after hepatectomy. Using selected variables, we created a scoring formula to classify patients with colorectal liver metastases to select good candidates for hepatic resection. The usefulness of the new scoring system was examined in a series of 92 patients from another hospital (Group II), comparing the number of selected variables.

RESULTS: Among 81 patients of GroupI, multivariate analysis, i.e. Cox regression analysis, showed that multiple tumors, the largest tumor greater than 5 cm in diameter, and resectable extrahepatic metastases were significant and independent prognostic factors for poor survival after hepatectomy (P < 0.05). In addition, these three factors: serosa invasion, local lymph node metastases of primary cancers, and post-operative disease free interval less than 1 year including synchronous hepatic metastasis, were not significant, however, they were selected by a stepwise method of Cox regression analysis (0.05 < P < 0.20). Using these six variables, we created a new scoring formula to classify patients with colorectal liver metastases. Finally, our new scoring system not only classified patients in GroupIvery well, but also that in Group II, according to long-term outcomes after hepatic resection. The positive number of these six variables also classified them well.

CONCLUSION: Both, our new scoring system and the positive number of significant prognostic factors are useful to classify patients with colorectal liver metastases in the preoperative selection of good candidates for hepatic resection.