Circulating tumour DNA may help predict recurrence in patients with early triple-negative breast cancer

It has been revealed that the presence of circulating tumour DNA (ctDNA) in early-stage triple-negative breast cancer can aid in independently predicting the risk of recurrence of the disease in patients who had undergone surgery after neoadjuvant chemotherapy. This may represent an important novel stratification factor for future post-neoadjuvant trials.

Patients with triple-negative breast cancer with residual disease have an exceptionally high risk of recurrence and novel therapies and technologies are thus essential, including those that can potentially predict the risk of relapse. ctDNA or plasma-derived tumour DNA is being explored as a way to detect cancer, guide treatment, and monitor patients during remission as the presence of ctDNA can signal the presence of cancer.

Researchers analysed plasma samples collected from 196 patients enrolled in the BRE12-158 clinical trial, which studied genomically directed therapy versus physician’s choice of treatment after preoperative chemotherapy in patients with triple-negative breast cancer [1]. In this study, ctDNA was sequenced in 142 patients and mutated ctDNA was detected in 63% of the patients. The most commonly mutated gene was TP53 followed by others that are commonly associated with breast cancer. At 17.2 months follow-up, detection of ctDNA was significantly associated with inferior distant disease-free survival (DDFS). Patients with ctDNA had a median DDFS of 32.5 months, while the patients without ctDNA did not reach the median. At 24 months, the DDFS probability was 56% in ctDNA-positive patients versus 81% in ctDNA-negative patients. The multivariate analysis controlled for factors such as residual cancer burden, tumour size, grade, stage, age, and race. Detection of ctDNA remained independently associated with inferior DDFS. It was shown that, overall, ctDNA-positive patients were 3 times as likely to have distant disease recurrence than ctDNA-negative patients. Detection of ctDNA was also associated with inferior overall survival as ctDNA-positive patients had an increased risk of death, 4.1 times higher than ctDNA-negative patients. It was pointed out though, that as the follow-up period is still ongoing, results may change in future analyses.

1. Radovich M, et al. GS5-02. SABCS 2019.

Posted on 13 February 202025 March 2024