Chemotherapy delivered directly in the liver in patients with colorectal cancer that has spread to the liver.

The aim of this study was to evaluate if hepatic arterial infusion chemotherapy (HAIC) could be beneficial for patients with colorectal cancer (CRC) that has spread to the liver (liver metastasis; LM). The study found that HAIC improved the outcome of these patients.

CRC is one of the most common types of cancer worldwide. A high number of patients with CRC have the tumor spread to other areas of the body (metastasis). One common site of metastasis is the liver. To treat LM, patients can undergo surgery to remove the tumor. Patients can be given chemotherapy (CT) to ensure all the cancer cells are removed after surgery (adjuvant therapy).

In some patients, the LMs are too difficult to remove by surgery. These patients can be given CT to treat the LM. In difficult-to-treat cases, CT can be given as palliative therapy (to improve the quality of the remaining life of the patient). There are different types of CT. CT that is given directly to the liver through the liver's main blood vessel (hepatic artery) is called HAIC. CT that is traditionally given to patients and travels through their entire body is called systemic CT (SC).

It is thought that by giving the CT directly to the liver with HAIC, some of the side effects of CT could be avoided. However, it is not yet clear whether HAIC is more beneficial than SC for patients with CRC who have LMs.

This study evaluated data from 18 clinical trials with 1,766 patients with CRC and LMs. 922 patients were given HAIC. 844 patients were given SC. In 10 studies, patients were given HAIC and SC as palliative therapy. In 8 studies, CT was given as curative therapy.

Overall, HAIC improved the chances of survival compared to SC. Patients in the HAIC group who received CT as palliative therapy had an 83% higher chance of a better survival compared to those who had SC. Patients who had HAIC as curative therapy had a 37% chance of a higher survival rate than those treated with SC.

Patients in the HAIC group had a 2 times better chance of the tumor responding to CT than those in the SC group. However, there was no significant difference in the length of survival without disease worsening between the HAIC and SC groups.

The study concluded that patients that have CRC with LM have a better outcome when treated with HAIC than SC.  

This study evaluated data from trials already completed. Not all trials were randomized. The duration of CT was not consistent between trials. The study did not discuss the difference in side effects between HAIC and SC in detail. Some studies reported higher side effects in the HAIC group.