Cetuximab Improves Survival in Advanced Colorectal Cancer

The addition of the targeted agent cetuximab (Erbitux) to chemotherapy improves survival among patients with colorectal cancer that has spread to the liver. These results were recently published in the Journal of Clinical Oncology.

The liver is a common site to which advanced colorectal cancer spreads, a condition which is referred to as liver metastasis. Optimal treatment for liver metastasis is the complete surgical removal of the tumors in the liver. Unfortunately, not all liver metastases are able to be surgically removed, either due to their location (ie, near a major vessel), their size, or due to the amount of cancer throughout the liver.

Often, patients not initially eligible for surgical removal of their liver metastases are treated with chemotherapy and/or targeted therapy in an attempt to shrink the sites of cancer enough so that surgery can become possible. For these patients, researchers continue to explore optimal treatment regimens to improve their survival outcomes.

Cetuximab is a targeted agent that blocks part of the epidermal growth factor receptor (EGFR) pathway. The EGFR pathway is involved in cellular growth and spread of cancer. Cetuximab binds to EGFR proteins on the surface of cancerous cells which ultimately halts or reduces the growth of these cells.

Researchers from Shanghai, China recently conducted a clinical trial to evaluate the effectiveness of cetuximab in the treatment of liver metastases among patients with colorectal cancer. The trial included 138 patients with colorectal cancer who had liver metastasis that was initially considered inoperable. One group of patients was treated with chemotherapy (FOLFIRI or mFOLFOX6) and one group was treated with the same chemotherapy regimens plus cetuximab. Patients did not have KRAS mutations.

At 3 years, overall survival was 41% for those who had received the addition of cetuximab, versus only 18% for those who received only chemotherapy.
The addition of cetuximab allowed for nearly 26% of patients to undergo surgical removal of their liver metastases, with no residual cancer observed, compared with only 7.4% of those who received only chemotherapy.
Among patients who received cetuximab, those who were able to subsequently undergo surgical removal of their liver metastases had a median survival time of 46.4 months.
For those who received cetuximab and were not able to undergo subsequent surgical removal of their liver metastases, median survival time was 25.7 months.
Median survival time for the entire group of patients who received cetuximab was approximately 31 months, compared with 21 months for patients who received chemotherapy only.
The researchers concluded that for patients with liver metastasis from colorectal cancer, the addition of cetuximab to chemotherapy resulted in a significant percentage of patients being able to undergo subsequent surgery compared to chemotherapy alone. Surgical removal of the liver metastases resulted in signifcantly improved survival for these patients.

Reference: Ye L-C, Liu T-S, Ren L, et al. Randomized Controlled Trial of Cetuximab Plus Chemotherapy for Patients With KRAS Wild-Type Unresectable Colorectal Liver-Limited Metastases. Jounal of Clinical Oncology. 2013; Published online before print April 8, 2013, doi: 10.1200/JCO.2012.44.8308.