Effect of chemotherapy on tumour-vessel relationship in colorectal liver metastases

Preoperative imaging of colorectal liver metastases: what the radiologist and the multidisciplinary team need to know

The management of patients with colorectal liver metastases (CRLM) has transformed over the past 2 decades. Advances in surgical techniques, systemic therapies, and local treatments have resulted in a paradigm shift. Disease that would once have been considered terminal is now frequently treated aggressively with both a disease-free and overall survival benefit. In line with the expanding range of treatment options, there has been an increase in the volume and complexity of imaging required in the management of these patients to ensure optimal patient selection and outcome. The radiologist plays a pivotal role in interpreting these studies, conveying the relevant information and informing the discussion at multidisciplinary team meetings. The purpose of this review is to provide an update for radiologists on the current surgical management of patients with CRLM highlighting specific imaging information that is required by the multidisciplinary team when assessing resectability and/or the need for additional liver-directed therapies.

A contemporary view on vascular resections and reconstruction during hepatectomies

Oncological hepatic surgery carries the possibility to perform vascular reconstructions for advanced tumours with vessel invasion since surgery often represents the only potentially curative approach for these tumours. An extended review was conducted in an attempt to understand and clarify the latest trends in hepatectomies with vascular resections. We searched bibliographic databases including PubMed, Scopus, references from bibliographies and Cochrane Library. Information and outcomes from worldwide clinical trials were collected from qualified institutions performing hepatectomies with vascular resection and reconstruction. Careful patient selection and thorough preoperative imaging remain crucial for correct and safe surgical planning. A literature analysis shows that vascular resections carry different indications in different diseases. Despite significant advances made in imaging techniques and technical skills, reports of hepatectomies with vascular resections are still associated with high postoperative morbidity and mortality. The trend of complex liver resection with vascular resection is constantly on the increase, but more profound knowledge as well as further trials are required. Recent technological developments in multiple fields could surely provide novel approaches and enhance a new era of digital imaging and intelligent hepatic surgery.

Locally advanced mid/low rectal cancer with synchronous resectable liver metastases: systematic review of the available strategies and outcome

The management of patients with locally advanced mid/low rectal cancer with resectable liver metastases is complex because of the need to combine the optimal treatment of both tumors. This study aims to review the available treatment strategies and compare their outcome, focusing on radiotherapy (RT) and liver-first approach (LFA). A systematic review was performed in PubMed, Embase, and web sources including articles published between 2000 and 02/2023 and reporting mid-/long-term outcomes. Overall, twenty studies were included (n = 1837 patients). Three- and 5-year overall survival (OS) rates were 51-88% and 36-59%. Although several strategies were reported, most patients received RT (1448/1837, 79%; > 85% neoadjuvant). RT reduced the pelvic recurrence risk (5.8 vs. 13.5%, P = 0.005) but did not impact OS. Six studies analyzed LFA (n = 307 patients). LFA had a completion rate similar to the rectum-first approach (RFA, 81% vs. 79%) but the interval strategy-an LFA variant with liver surgery in the interval between radiotherapy and rectal surgery-had a better completion rate than standard LFA (liver surgery/radiotherapy/rectal surgery, 92% vs. 75%, P = 0.011) and RFA (79%, P = 0.048). Across all series, LFA achieved the best survival rates, and in one paper it led to a survival advantage in patients with multiple metastases. In conclusion, different strategies can be adopted, but RT should be included to decrease the pelvic recurrence risk. LFA should be considered, especially in patients with high hepatic tumor burden, and RT before liver surgery (interval strategy) could maximize its completion rate.

Impact of Pre-Liver Transplant Treatments on the Imaging Accuracy of HCC Staging and Their Influence on Outcomes

The outcome of liver transplantation (LT) for hepatocarcinoma (HCC) is strongly influenced by HCC staging, which is based on radiological examinations in a pre-LT setting; concordance between pre-LT radiological and definitive pathological staging remains controversial. To address this issue, we retrospectively analyzed our LT series to assess concordance between radiology and pathology and to explore the factors associated with poor concordance and outcomes. We included all LTs with an HCC diagnosis performed between 2013 and 2018. Concordance (Co group) was defined as a comparable tumor burden in preoperative imaging and post-transplant pathology; otherwise, non-concordance was diagnosed (nCo group). Concordance between radiology and pathology was observed in 32/134 patients (Co group, 24%). The number and diameter of the nodules were higher when nCo was diagnosed, as was the number of pre-LT treatments. Although concordance did not affect survival, more than three pre-LT treatments led to a lower disease-free survival. Patients who met the Milan Criteria (Milan-in patients) were more likely to receive ≥three prior treatments, leading to a lower survival in multi-treated Milan-in patients than in other Milan-in patients. In conclusion, the concordance rate between the pre-LT imaging and histopathological results was low in patients with a high number of nodules. Multiple bridging therapies reduce the accuracy of pre-LT imaging in predicting HCC stages and negatively affect outcomes after LT.

Preoperative chemotherapy in upfront resectable colorectal liver metastases: New elements for an old dilemma?

The use of preoperative or "neoadjuvant" chemotherapy (NAC) has long been controversial for resectable colorectal liver metastases (CRLM). The European Society of Medical Oncology (ESMO) 2023 guidelines on metastatic colorectal cancer (CRC) indicate a combination of surgical/technical and oncologic/prognostic criteria as the two determinants for allocating patients to NAC or upfront hepatectomy. However, surgical and technical criteria have evolved, and oncologic prognostic criteria date from the pre-modern chemotherapy era and lack prospective validation. The traditional literature is interpreted as not supporting the use of NAC because several studies fail to demonstrate a benefit in overall survival (OS) compared to upfront surgery; however, OS may not be the most appropriate endpoint to consider. Moreover, the commonly quoted studies against NAC contain many limitations that may explain why NAC failed to demonstrate its value. The query of the recent literature focused primarily on other aspects than OS, such as surgical technique, the impact of side effects of chemotherapy, the histological growth pattern of metastases, or the detection of circulating tumor DNA, shows data that support a more widespread use of NAC. These should prompt a critical reappraisal of the use of NAC, leading to a more precise selection of patients who could benefit from it.

Laparoscopic Ultrasound-Guided R1 Vascular Liver Resection for Colorectal Liver Metastases at Caval Confluence

BACKGROUND

Patients with tumors involving the hepatic vein (HV) at the caval confluence (CC) usually receive major hepatectomies or HV grafting. For colorectal liver metastases (CLM), tumor-vessel detachment (R1vasc) has proven to be oncologically adequate.^1-3 However, parenchyma-sparing R1vasc surgery has usually been confined to the open approach. The technical tricks for accomplishing this kind of surgery in laparoscopy are disclosed.

METHODS

A patient with a CLM in contact with the middle HV (MHV) and left HV (LHV) at the CC underwent liver resection. No signs of vascular invasion were observed at preoperative imaging. On the basis of the low rate of tumor-vessel regression after chemotherapy,⁴ technical feasibility, and low tumor burden, patient was considered for upfront surgery. Surgery consisted in: (1) left liver mobilization with full exposure of the CC; (2) identification of the common trunk's root and its encirclement by tape; (3) the use of ultrasound to rule out HV invasion and to define a resection area favoring a transection plane smoothly approaching the point of vascular contact; and (4) careful vascular detachment by blunt dissection in a caudocranial fashion to separate the lesion from HVs.

RESULTS

A limited resection of segments, four superior and two with MHV-LHV detachment, was performed. Operation time was 285 min, with 52 min of cumulative Pringle time and 20 ml of blood loss. Postoperative course was uneventful. The in-hospital stay was 6 days.

CONCLUSION

Similarly to open surgery, laparoscopic R1vasc surgery for CLM at CC is feasible and represents an alternative to major hepatectomy. HV control by tape is recommended to manage any bleeding that may occur during tumor-vessel detachment.