News

PhD Student's Research Bringing New Hope For Liver Cancer Patients


2 March 2010

Patients diagnosed with metastatic liver cancer that cannot be removed surgically have a very short life expectancy. Kathy Willowson, a PhD student in the University of Sydney's School of Physics, is undertaking research that focuses on obtaining quantitative data from nuclear medicine SPECT images. This information is then used to help in the diagnosis and treatment of disease, in particular, investigating the potential of this technique to improve the treatment of metastatic liver cancer.

Kathy Willowson analysing a patient scan to look at the distribution of radioactivity in the liver and lungs. This is a planning study from which Kathy can start to calculate dose distribution for therapy.
Kathy Willowson analysing a patient scan to look at the distribution of radioactivity in the liver and lungs. This is a planning study from which Kathy can start to calculate dose distribution for therapy.

Currently the only available treatment option is palliative and not curative and consists of Selective Internal Radiation Therapy (SIRT). SIRT involves an invasive procedure where millions of microscopic beads labelled with Yttrium-90 (a beta emitter which is ideal for therapy as it has a short range in tissue) are pumped through a catheter to the site of the liver, such that the tumour itself receives a high radiation dose, but the remainder of the body is relatively spared.

However, some of these radioactive beads get pushed to the lungs delivering a potentially damaging radiation dose leading to major complications. If there is a risk of a too high radiation dose to the lungs, therapy should not go ahead, however this leaves the patients with no alternative treatment.

Whilst this is a mostly effective therapy there is room for improvement. Kathy's research focuses on the benefits of a full quantitative evaluation of these patients in order to calculate how much dose the lungs will receive at therapy, and then from this deliver therapy doses tailored specifically to the individual patient. Such a method should give maximum dose to the tumour yet keeping the dose to the lungs below an acceptable threshold. "Ultimately, we are hoping that this work will improve the survival times of these patients, which is currently only 6-12 months following such therapy," says Kathy.

Kathy says her research will play a role in improving diagnosis in many areas of nuclear medicine. "Quantitative SPECT is a fairly new area that is only now opening up due to the introduction of combined SPECT/CT systems. This research will lead to many new possibilities and help address many clinical limitations that currently exist."

Results from her research are already showing as the quantitative technique is used in a growing number of clinical research projects, and collaborations with other areas and departments develop. "I am about to undertake a year of research working directly with the company that make the therapy product, and I hope that by the end we will have made good progress in stepping towards full quantitative analysis as routine assessment of these patients."

Based at at the Royal North Shore Hospital in the Department of Nuclear Medicine where much of her medicine takes place, Kathy is currently working in conjunction with Sirtex Medical, an Australian company based at Lane Cove who make the resin microscopic beads used for such therapy. "Working directly with the company itself, and combining patient data from multiple hospital sites around Sydney, we have the chance to put this technique into practice with the aim of providing optimum benefits to the patient."

Kathy's research has recently been awarded a grant of over $100,000 for 12 months through the Enterprise Connect Researchers in Business Award, which will co-fund her work in conjunction with Sirtex Medical. She says her PhD research is challenging but extremely rewarding. "Medical physics really appeals to me as it allows you to investigate challenging problems, yet also see how they benefit others. It's amazing to see how much physics is behind medicine."