Liver transplantation in metastatic colorectal cancer: are we ready for it?

Primary tumor sidedness is not prognostic factor in resectable colorectal cancer liver metastasis: a retrospective observational cohort study

Purpose

Right-sided tumors have been reported to have a poorer survival rate than left-sided tumors; however, there remains debate regarding whether sidedness is an independent prognostic factor in colorectal cancer liver metastasis (CRLM). This study aimed to assess the impact of sidedness on prognosis in resectable CRLM and to identify prognostic factors.

Methods

Patients who underwent liver resection for CRLM at Samsung Medical Center from January 2008 to December 2021 were included in the investigation. Overall survival (OS) and progression-free survival (PFS) were analyzed, and prognostic factors were identified.

Results

A total of 497 patients were included in the study, with 106 on the right side and 391 on the left side. The right-sided group had a higher percentage of synchronous tumors (90.6% vs. 80.3%, P = 0.020). In survival analysis, the right side showed lower 5-year OS (49.7% vs. 54.2, P = 0.305) and 5-year PFS (57.1% vs. 60.2%, P = 0.271), but the differences were not statistically significant. In the analysis of prognostic factors, synchronous tumor (odds ratio [OR], 5.01; P < 0.001), CEA (OR, 1.46; P = 0.016), and maximum tumor size of hepatic metastasis (OR, 1.09; P = 0.026) were associated with OS.

Conclusion

In resectable CRLM, there was no difference in prognosis based on sidedness. CEA level, synchronous tumor, and maximum tumor size of hepatic metastasis were identified as prognostic factors.

Translating efficacy of liver transplantation in liver-limited metastatic colorectal cancer into clinical practice: the TransMet trial

Pioneer studies suggested that liver transplantation (LT) has the potential to provide long-term survival in patients with liver-limited metastatic colorectal cancer (mCRC) not amenable for surgery of metastases. Evidence, however, was limited to single-arm studies with few patients enrolled and suboptimal selection criteria, with concerns over access to organ availability overcoming the potential efficacy of LT in this setting. Recently, 5-year survival rates with chemotherapy followed by LT (73%) compared with chemotherapy alone (9%) have been demonstrated by the randomized TransMet trial, enrolling 94 definitively unresectable strictly selected liver-limited mCRC patients. These findings should now prompt clinical oncologists to reconsider LT as a valuable option for unresectable liver-limited mCRC patients meeting TransMet criteria, and transplantation agencies to adapt their policies of access to organ donation.

Expanding MELD exceptions for colorectal liver metastasis: data and policy

PURPOSE OF REVIEW

While liver transplant for unresectable colorectal cancer liver metastases (CRLM) has been demonstrated to be a promising treatment in selected patients, the typically low MELD score of these patients and lack of exception points may lead to challenges in receiving a deceased donor liver for transplant.

RECENT FINDINGS

Several studies have shown improved outcomes in select patients with CRLM who undergo liver transplant, and several trials are ongoing and will conclude in the next several years. MELD exception points have recently been proposed in qualifying patients with CRLM to help this group obtain more timely quality allografts. Under the current proposal, patients with CRLM would receive a score of the median MELD at transplant (MMaT) for their center minus 20 with a minimum score of 15 in cases where MMaT minus 20 would be less than 15. This would allow them to receive transplants faster without competing unnecessarily with those with greater medical need.

SUMMARY

Giving MELD exception points to patients with colorectal cancer liver metastases in need of transplant may decrease time on the waitlist and improve outcomes for these patients.

Prognostic factors associated with early recurrence following liver resection for colorectal liver metastases: a systematic review and meta-analysis

BACKGROUND

Colorectal cancer (CRC) is the 3rd most common malignancy with the liver being the most common site of metastases. The recurrence rate of colorectal liver metastases (CRLM) after liver resection (LR) is notably high, with an estimated 40% of patients experiencing recurrence within 6 months. In this context, we conducted a meta-analysis to synthesize and evaluate the reliability of evidence pertaining to prognostic factors associated with early recurrence (ER) in CRLM following LR.

METHODS

Systematic searches were conducted from the inception of databases to July 14, 2023, to identify studies reporting prognostic factors associated with ER. The Quality in Prognostic Factor Studies (QUIPS) tool was employed to assess risk-of-bias for included studies. Meta-analysis was then performed on these prognostic factors, summarized by forest plots. The grading of evidence was based on sample size, heterogeneity, and Egger's P value.

RESULTS

The study included 24 investigations, comprising 12705 individuals, during an accrual period that extended from 2007 to 2023. In the evaluation of risk-of-bias, 22 studies were rated as low/moderate risk, while two studies were excluded because of high risk. Most of the studies used a postoperative interval of 6 months to define ER, with 30.2% (95% confidence interval [CI], 24.1-36.4%) of the patients experiencing ER following LR. 21 studies were pooled for meta-analysis. High-quality evidence showed that poor differentiation of CRC, larger and bilobar-distributed liver metastases, major hepatectomy, positive surgical margins, and postoperative complications were associated with an elevated risk of ER. Additionally, moderate-quality evidence suggested that elevated levels of carcinoembryonic antigen (CEA) and carbohydrate antigen 19-9 (CA199), lymph node metastases (LNM) of CRC, and a higher number of liver metastases were risk factors for ER.

CONCLUSION

This review has the potential to enhance the efficacy of surveillance strategies, refine prognostic assessments, and guide judicious treatment decisions for CRLM patients with high risk of ER. Additionally, it is essential to undertake well-designed prospective investigations to examine additional prognostic factors and develop salvage therapeutic approaches for ER of CRLM.

Liver Transplantation for Unresectable Colorectal Liver Metastasis: Perspective and Review of Current Literature

The treatment of unresectable colorectal liver metastasis (CRLM) has previously been limited to palliative chemotherapy. Traditionally, the role of liver transplant has not been associated with sufficient survival to justify a patient undergoing a major operation with the associated requirement for postoperative immunosuppression. With improvements in chemotherapy options, a certain subset of patients can experience stable disease for years, which has prompted investigation into the role of liver transplant in these patients. Several recent studies have shown promising results in well-selected patients, with posttransplant survival approaching that of liver transplant recipients for other diseases. Here, we present a review of the data and current protocols for liver transplant for unresectable CRLM.

Liver transplantation in colorectal metastases. Is there an indication for this procedure?

Almost 25 % of patients with colorectal cancer present metastases at the time of diagnosis and 50 % go on to develop metastases in the course of the disease. Surgical resection is the only curative treatment although only between 20 % and 30 % of patients present resectable lesions. Although liver transplantation is contraindicated in unresectable metastases of colorectal cancer, ever since the publication of the results of a pilot study there has been renewed interest in transplantation in these patients. In two consecutive trials overall and recurrence-free 5-year survival rates of 83 % and 35 % respectively, have been reported, Currently several trials are ongoing which are expected to allow the patient selection criteria for the indication of liver transplantation to be refined.

Update to 'A Contemporary Systematic Review on Liver Transplantation for Unresectable Liver Metastasis of Colorectal Cancer'

Colorectal cancer is the second most common cause of cancer-related death worldwide, and half of patients present with colorectal liver metastasis (CRLM). Liver transplant (LT) has emerged as a treatment modality for otherwise unresectable CRLM. Since the publication of the Lebeck-Lee systematic review in 2022, additional evidence has come to light supporting LT for CRLM in highly selected patients. This includes reports of >10-year follow-up with over 80% survival rates in low-risk patients. As these updated reports have significantly changed our collective knowledge, this article is intended to serve as an update to the 2022 systematic review to include the most up-to-date evidence on the subject.