New blood test trialled to spare unnecessary chemotherapy

17 October 2018 (Last Updated October 17th, 2018 10:30)

A new blood test is currently being trialled at more than 40 hospitals in Australia and New Zealand to prevent cancer patients from unnecessary chemotherapy.

New blood test trialled to spare unnecessary chemotherapy
Micrograph of an invasive cecal adenocarcinoma. Credit: Nephron

A new blood test is currently being trialled at more than 40 hospitals in Australia and New Zealand to prevent cancer patients from unnecessary chemotherapy.

The circulating tumour DNA (ctDNA) test, which is developed through a collaboration between the Walter and Eliza Hall Institute of Australia, and Johns Hopkins Kimmel Cancer Centre of US, can determine if fragments of tumour DNA are present in a patient’s blood after the surgical removal of tumours.

Currently, there is no reliable way of ascertaining whether a tumour has been completely removed or not. As a result, patients undergo chemotherapy treatment as a preventive step.

“Results from this blood test could allow the increase or decrease of dosages for patients who require chemotherapy based on the risk factor.”

The trial lead, who is a clinician scientist at the Walter and Eliza Hall Institute and a medical oncologist at the Peter MacCallum Cancer Centre and Western Health, Associate Professor Jeanne Tie said: “While chemotherapy is an essential, life-saving treatment, we don’t want patients receiving it if they don’t need it. We want to help these patients avoid serious and ongoing side-effects associated with chemotherapy.”

Chemotherapy leads to several harmful side effects including nausea, digestive issues, bleeding problems, fertility issues, and increased vulnerability to infection.

Results from this blood test could allow the increase or decrease of dosages for patients who require chemotherapy based on the risk factor.

Tie added: “We would like to be able to tell some patients that they can safely avoid chemotherapy because their cancer is unlikely to recur.”

“But for patients who are at a high risk of recurrence, we want to be able to give them a more intensive dose of chemotherapy than those with a lower risk of recurrence.”

In 2015, the test focused on early stage bowel cancer patients, and following its success, it was extended to patients suffering from ovarian cancer in 2017.

The ovarian cancer wing of the trial is led by Walter and Eliza Hall Institute clinician-researcher Associate Professor Sumi Ananda, who is also a medical oncologist at the Peter MacCallum Cancer Centre and Western Health.

Ananda said: “We suspect that many women with early-stage ovarian cancer can be treated with surgery alone, but we currently treat all these patients as though their cancer may recur, with high dose chemotherapy.

“Undergoing chemotherapy is a huge imposition on a patient’s life, both because of the side-effects patients have to endure, as well as the time the treatment takes.”

Approximately 400 patients have participated in the trial and plans are on to expand this programme to 2,000 patients before its conclusion in 2021.

(Additional reporting by Shalini Nair)