Selective Internal Radiation Therapy – Breakthrough New Cancer Treatment Methods

As part of the world’s biggest clinical trial on the treatment of cancer, Professor Gibbs along with other researchers in Melbourne have devised a new cancer treatment method called the Selective Internal Radiation Therapy (SIRT). As part of the clinical trial, hundreds of people with inoperable liver cancer were treated with SIRT in conjunction with sorafenib – a chemotherapy drug.

The SIRT are meant for patients whose cancer prevention cannot be done through surgery such as the hepatic cell carcinoma. In this new cancer prevention method, the researchers used tiny radioactive beads that were injected into the arteries that supply for the tumor growth. These tiny radioactive beads or microspheres are made of glass or resin.

How do the microspheres help?

The microspheres act as a medium to block the blood passage to the tumors. Currently the therasphere and the SIR – spheres, two types of the microspheres, are used in the new cancer treatment process.

Before the SIRT treatment, the patient needs to get three tests done:

-       Hepatic Angiogram: Checks the arterial anatomy and helps the radiologist find the arteries which can carry the radioactive beads away from the target location. The radiologist diverts such arteries to the lungs or the gastrointestinal system.

-       Technetium Macroaggregated Albumin Scan: Checks the percentage of lung shunting. Patients with more than 20% of lung shunting are not recommended SIRT. Increased lung shunting means that the radioactive particles can travel down to the lungs and do considerable damage.

-       CT scan: Checks the exact size of the cancer tumor for the radiologist to determine the correct dose of radioactive beads required.

The process of microspheres injection is checked with the help of Bremsstrahlung image that uses gamma camera. After the SIRT new cancer treatment, the patient undergoes PET scan after several weeks to determine whether the treatment has any effect on the cancer or not. Current statistics show that one – third of the patients do not respond to the treatment and the remaining two – third do.

In the clinical trial done by the Royal Melbourne Hospital, one of the patients reported complete cured from the tumor. The Herald Sun quoted Professor Gibbs saying, “her tumors slowly disappeared and she remains tumor free. I am convinced that she is cured”.