Combining radiation therapy and chemotherapy to treat patients with advanced liver cancer lengthens overall survival, according to research presented on October 24 at the American Society for Radiation Oncology (ASTRO) annual meeting in San Antonio.
Results from a phase III clinical trial show that stereotactic body radiation therapy (SBRT) should be the standard treatment for liver cancer patients who are unable to undergo resection or other local-regional therapies, presenter Dr. Laura Dawson of the University of Toronto said.
"Adding radiation therapy to systemic therapy delayed tumor progression and lengthened survival, without an increase in side effects," Dawson said in a statement released by ASTRO. "In all regards, the combination of radiation therapy and [chemotherapy agent] sorafenib appears more effective than the drug on its own."
Chemotherapy is the go-to treatment for people with hepatocellular carcinoma who can't withstand surgery or other invasive treatments, Dawson noted. But new studies suggest that radiation therapy can benefit these patients.
To test this hypothesis, Dawson and colleagues conducted a trial that included 177 patients with new or recurring liver cancer who were ineligible for surgical resection or other local or regional standard therapies because of clinical factors (such as the cancer had invaded the liver's vasculature) or because their cancer had returned after standard therapy.
Study participants were randomized to receive either chemotherapy alone or radiation therapy followed by chemotherapy. The radiation therapy was delivered in five episodes over five to 10 days with total doses ranging between 27.5 Gy and 50 Gy.
The trial revealed that overall survival was longer for individuals who had the combination of radiation and chemotherapy compared to those who underwent chemotherapy alone -- a difference that was statistically significant when the researchers controlled for the degree of the cancer's spread to the liver's vasculature (p = 0.042).
| Comparison of outcomes in patients with advanced liver cancer by treatment protocol | ||
| Outcome | Chemotherapy alone | Radiation therapy plus chemotherapy |
| Overall survival | 12.3 months | 15.8 months |
| Progression-free survival | 5.5 months | 9.2 months |
| Interval before cancer progressed | 9.5 months | 18.5 months |
| Side effects (severe) | 42% | 47% |
| Treatment-related deaths | 1 | 0 |
Dawson "hopes the findings spark an increased interest in future clinical trials to study the benefit of radiation therapy combined with newer drug therapies," according to the ASTRO statement.
"There is a growing number of preclinical and early clinical studies suggesting that SBRT may be synergistic with immunotherapy, with more than an additive benefit for patients," she said.
