Dr Liu on SBRT and IMRT in Colorectal Cancer

“Radiation evolves a lot with technology, so when you think about how much technology has evolved in the past few decades, it gives you an idea of how much radiation has come along during that time as well.”

Yufei Liu, MD, PhD, assistant clinical professor in the Department of Radiation Oncology at City of Hope, discusses the role of radiation and how radiation strategies have shaped treatment options in colorectal cancer (CRC) during CRC Awareness Month, observed annually in March.

Radiation therapy continues to evolve as technology has been upgraded, which underscores the improvements that have been made with radiation in recent years, Liu begins. When radiation was first utilized in cancer care, it was primarily used with X-ray guidance, which the X-ray helped visualize the general area where the radiation would be directed, he explains. However, in current practice, CT and MRI guidance is more commonly used when designing radiation plans, he says. Now, stereotactic body radiation therapy (SBRT) and intensity modulated radiation therapy (IMRT) allow for shaping the radiation dose more accurately, he emphasizes. More precise targeting also helps spare normal organs from radiation, including the bladder and intestines.

With SBRT, the most significant advantage is its ability to carry out a highly conformal radiation dose, Liu continues. He notes that this strategy can provide high-dose radiation to the location of the tumor that quickly falls off once the beam is no longer in contact with the tumor, which can also protect normal tissue from the effects of radiation.

In patients with rectal cancer, radiation therapy is the mainstay, particularly in patients with locally advanced disease, Liu explains. However, for patients with colon cancer, he says combining surgery with chemotherapy can also be a curative option and radiation is often utilized in those who aren’t able to tolerate surgery or aren’t good candidates for surgery. Furthermore, for patients with metastases to the lungs or liver, radiation can help improve treatment outcomes, he adds. Liu concludes that radiation therapy can also offer pain relief in patients with advanced cancers who have bone or muscle metastases.