Meet the expert: Dr Boon Chua

Intro text: 

Meet Dr. Boon Chua, Director of the Breast Service at Peter MacCallum Cancer Centre in Melbourne, Australia and primary investigator of the "Finely Tuned Radiotherapy" (scientific name: DCIS) project

BIG : What is DCIS (Ductal Carcinoma In Situ) and how much do we know about it?

Dr. Boon Chua : DCIS is generally considered a form of non-invasive breast cancer, some of which could progress to become invasive cancer. It is a growing health problem since mammographic screening is widely available in many countries; today, it accounts for up to 25% of new breast cancer diagnoses. However, in contrast to invasive breast cancer, there has been comparatively little research on DCIS. As a result, there are often uncertainties on how individual patients with DCIS may best be managed, especially to reduce the risk of their DCIS from becoming an invasive breast cancer.

What is the purpose of the “Finely Tuned Radiotherapy” (DCIS) study and how will patients benefit?

Radiotherapy to the breast reduces the risk of the DCIS recurring after breast conserving surgery. The recurrence could be in the form of an invasive breast cancer or another DCIS. The main purpose of the “Finely Tuned Radiotherapy” study is to investigate if a higher radiation dose, known as a ‘boost,’ given to the part of the breast where the DCIS occurred, could reduce the risk of recurrence in women with high-risk DCIS. The boost radiation has been shown to benefit selected women with invasive breast cancer but this research has not been done in DCIS in a large, well-designed clinical trial. On the other hand, the boost radiation may cause more side effects such as breast scarring and poorer cosmetic result. So it is important that we use the boost radiation only if it is of clear benefit to individual patients.

The study also tests if a shorter three-week course of breast radiotherapy is at least as effective as a longer five-week course. This is shown to be the case for invasive breast cancer but such a study has not been done for DCIS. The shorter course of radiotherapy would be more convenient and, in some countries, less costly for the patients.   

A high priority in breast cancer research is to work out which patients with DCIS may develop an invasive breast cancer, and what this risk is in individual patients. At present, there is no reliable test to answer these questions. Patients in our study have been providing tissue samples to support this important research so that we may tailor a patient’s treatment according to her risk of recurrence. The ultimate goal of our research is to personalise the treatment of each patient with DCIS to her recurrence risk to avoid over-treatment leading to unnecessary side effects, or under-treatment resulting in recurrence. 

What were the challenges of launching this project?

We started this study in 2007 in Australia and expanded internationally to include 11 countries.  Thanks to the strong support of BIG researchers worldwide, and their will to conduct this academic trial without commercial sponsorship, 1.608 women were recruited as of June 2014, a full two years ahead of schedule.  This outstanding achievement demonstrates that research on DCIS is considered a high priority for many patients and researchers. 

The on-going challenge is to ensure that this academic study is completed successfully, as we need to follow up the patients for 10 years in order to achieve the purpose of the study. Considerable resources are required for the study to yield meaningful outcomes, particularly to obtain the cutting-edge biomarker information that will allow us to personalize treatment. I believe we have an obligation to the 1.608 patients taking part in the study, and future patients diagnosed with DCIS to complete the study successfully, to help provide the critical information that is lacking at present to achieve the best possible outcomes for the patients.

What makes this project unique?

This is one of a few large-scale clinical trials for DCIS that has highly standardized processes for both collection of patient data and tumour samples, and tissue analysis. This will provide a very valuable, unique and high quality resource to support DCIS research that would deliver the most benefits for the patients. 

Why is it important for this study to be conducted internationally?

We have 136 participating centres worldwide with patients from Australia, Belgium, the Netherlands, France, Switzerland, Italy, the United Kingdom, Ireland, New Zealand, Singapore, and Canada. This is a large clinical trial, and to accrue patients successfully, the support of patients and researchers internationally is absolutely essential.  BIG has been instrumental in facilitating this international collaboration. In addition, DCIS affects women all around the world, and the results of our study will likely have a significant impact on how patients with DCIS are best managed worldwide. 

Why should people support the project?

As DCIS is an increasingly common diagnosis, there is urgency that we resolve the unanswered questions that patients and doctors frequently encounter.  It is very timely that this study is being conducted to address these critical questions. 

It is very important that we personalise the treatment of patients with DCIS according to their individual risks of recurrence to avoid over- or under-treating them. As the majority of these patients are, fortunately, long-term survivors, we need to minimize not only the risk of recurrence but also the long-term side effects of treatment to give them the best quality of life possible.