Liver transplant improves survival for certain patients with colorectal cancer liver metastases
August 2023
A recent study demonstrated that a liver transplant provided a 10-year overall survival (OS) rate of more than 80% for selected patients with colorectal cancer (CRC) and nonresectable liver metastases.
Non-resectable liver metastases: liver metastases that cannot be safely removed with surgery, for reasons such as the metastatic tumours invading the major blood vessels of the liver.
The liver is the primary site of metastasis among patients with CRC, and the development of liver metastases has a strong impact on patients’ OS, with a median 5-year OS of less than 14% with palliative chemotherapy[1]. While liver transplantation may be a promising treatment option for patients with CRC and nonresectable liver-only metastases, the data to support this option come from small trials without a very clear understanding of which patients within this subgroup are most likely to benefit.
The study
In the 1990s, liver transplantation for patients with colorectal cancer was abandoned as a treatment option due to poor survival. The researchers in this current study aimed to reexamine whether liver transplantation could result in longer overall survival among select patients. In the study, the researchers also identified factors that could predict a negative impact of liver transplant on OS for patients.
The researchers gathered data from three clinical trials assessing liver transplant for colorectal cancer liver metastases conducted at Oslo University in Norway between 2006 and 2020. Data from a total of 61 patients were analyzed.
Disease-free survival, overall survival and survival time after recurrence were the study’s primary outcomes.
Disease-free survival: the amount of time after treatment during which no sign of cancer is found.
The researchers found that negative predictive factors (i.e. factors that suggested the patient would not benefit from liver transplantation) included large liver tumour size (greater than 5.5cm), disease that progressed on chemotherapy, CEA blood levels greater than 80g/L, primary tumour in the ascending colon, tumour burden score of 9 or higher, and nine or more liver metastases (lesions).
Findings
The study results demonstrated that a 10-year OS of 80% or higher can be achieved after liver transplant for colorectal cancer metastases in highly selected cases where patients did not have any of the above-mentioned negative predictive factors. Critique of this study suggest that the patient population that was eligible for this type of surgery is rare, with patients surviving an average of 21 months from diagnosis to transplant while remaining healthy enough for a liver transplant. Nonetheless, the study has shown that there is indeed a small group of patients with unresectable colorectal liver metastases who meet certain favourable prognostic criteria who may be considered for transplant, with achievable long-term survival and even cure. This provides a potential treatment option among patients with few treatment options available.
[1] https://www.nature.com/articles/s41416-023-02213-1
