SBRT Is a Standard for Colorectal Liver Metastases: Michael David Chuong, MD

Stereotactic body radiation therapy (SBRT) has emerged as a cornerstone in the treatment of colorectal liver metastases, now featured in national and international guidelines from organizations such as the National Comprehensive Cancer Network (NCCN) and the American Society of Clinical Oncology (ASCO), says Michael David Chuong, MD, radiation oncologist, Miami Cancer Institute, Baptist Health South Florida. SBRT is especially beneficial for patients who are not surgical candidates or whose tumors are unsuitable for ablation, providing a viable alternative in complex cases.

Chuong presented on this topic at this year’s ASCO Gastrointestinal (GI) Cancers Symposium during a session titled “Liver-Directed Approaches and Transplantation for Unresectable Colorectal Liver Metastasis.”

This transcript was lightly edited for clarity; captions were auto-generated.

Transcript

SBRT is a standard of care for colorectal liver metastases. Can you discuss the consensus guidelines that support this?

Radiation therapy, specifically SBRT, which is also called stereotactic body radiation therapy, has actually been a standard of care for the treatment of colorectal liver metastases for a number of years and, in fact, has been included within national and international expert consensus guidelines within a number of different organizations. SBRT has been included within a number of national and international guidelines for a number of years, and this includes the National Comprehensive Cancer Network, or NCCN guidelines, as well as ASCO guidelines, among other guidelines. These recommendations are based on clinical trial data demonstrating the efficacy and safety of SBRT for the treatment of colorectal liver metastases, which can be highly beneficial to patients, especially when other modalities such as percutaneous ablation or systemic therapies alone are not either feasible or effective.

Which patients are best suited to receive radiation therapy as an alternative to surgery?

Patients with colorectal liver metastases who would best be suited to receive radiation therapy are typically patients who are not good surgical candidates, so they have medical comorbidities, or say, have had prior liver resections, and more liver resections may not be feasible or safe, in which case we would consider either radiation or ablation. And typically, radiation therapy would be done for tumors that are in unsuitable locations or are of a large size that would not be appropriate for ablation. For example, tumors larger than 3 or 3.5 centimeters are typically better suited and have better local control outcomes with radiation as opposed to ablation. Also, historically, tumors that are in certain anatomic locations, for example, near the dome of the liver, abutting the diaphragm, or abutting certain vascular structures like the IVC [inferior vena cava], may not be good candidates for RFA [radiofrequency ablation] or other ablative procedures.