Proton Therapy for Liver Cancer

About Liver Cancer Treatment

Liver cancer represents the sixth most commonly diagnosed cancer and the third leading cause of cancer death worldwide. Hepatocellular carcinoma (HCC) is a specific type of cancer that accounts for 90% of all liver cancers. Unfortunately, survival rates historically have been low as liver cancer can be aggressive and is often found after the disease has progressed.

Potential treatments include surgery, chemotherapy, liver transplantation and radiation. While radiation can be a good treatment, it can be challenging to deliver as it takes high doses of radiation to kill liver tumors and the healthy liver tissue is relatively susceptible to radiation damage.

Proton therapy has proven clinical results

The ability of protons to precisely target the tumor and avoid hitting healthy tissue makes it a very good option to treat certain liver cancers. Treatment planning studies have shown the ability to significantly reduce the average radiation dose hitting healthy liver with protons versus other types of radiation treatment.

Studies have also shown that protons can reduce side effects and increase over survival versus other forms of radiation treatment.

For example, one study found a 19% increase in survival at 5 years and a 60% reduction in severe long-term side effects with protons versus photon based treatment¹ . Another study out of Massachusetts General Hospital found that average overall survival more than doubled with proton therapy versus photon therapy while radiation induced liver disease was reduced by 26%.²

^{1)Qi WX, Fu S, Zhang Q, Guo XM. Charged particle therapy versus photon therapy for patients with hepatocellular carcinoma: a systematic review and meta-analysis. Radiother Oncol (2015)
114(3):289–95. doi: 10.1016/j.radonc.2014.11.033}

^{2)Sanford NN, Pursley J, Noe B, Yeap BY, Goyal L, Clark JW, et al. Protons versus photons for unresectable hepatocellular carcinoma: Liver decompensation and overall survival. Int J Radiat Oncol Biol Phys (2019) 105(1):64–72. doi: 10.1016/j.ijrobp.2019.01.076}

The image above shows how radiation delivered with X-Rays or photons (left) can spread and hit healthy tissue organs while protons (right) are primarily confined to the tumor.