The presence of circulating tumour DNA (ctDNA) is a crucial biomarker for patients with bladder cancer (urothelial carcinoma) researchers have found in a new study. Scientists suggest that post-operative screening for ctDNA could improve cancer treatments and patient outcomes. The authors hope the findings could help improve outcomes for bladder cancer and more broadly illustrates the potential for personalised cancer treatments.

During the study, published in the journal Nature, scientists studied the outcomes of 581 patients who had undergone surgery for urothelial carcinoma and evaluable for ctDNA. Specifically, they compared the outcomes of post-surgical patients treated with the immunotherapy adjuvant atezolizumab, against those who underwent observation.

The authors hypothesised that the presence of ctDNA is associated with a worse disease prognosis. They proposed that treatment with immunotherapies will have the most significant impact on survival rates in these patients.

The findings supported their hypothesis. “These data suggest that adjuvant atezolizumab may be associated with improved outcomes compared with observation in patients who are positive for ctDNA and who are at a high risk of relapse,” say the authors.

The situation is complex, as not all patients receive treatment with adjuvant atezolizumab. “Many patients who are cured by surgery are unnecessarily exposed to adjuvant therapy toxicities,” warn the authors. In contrast, others who could benefit from it don’t receive it until disease progression is identified through imaging. The situation means that many patients are exposed to a drug they don’t need to take; or are refused access to effective medication until their condition has worsened.

Screening for ctDNA shortly after surgery could overcome these limitations, say the authors. Genetic screening, where a blood sample or tumour is analysed, can provide clinicians with critical information on the spread of a disease, its progression and effective treatment.

The process would provide early detection for ctDNA, which could be treated with immunotherapies, leading to better outcomes. The authors state that “Minimally invasive approaches to detect residual disease after surgery are needed to identify patients with cancer who are at risk for metastatic relapse.”

In conclusion, the authors summarise that “Circulating tumour DNA (ctDNA) holds promise as a biomarker for molecular residual disease and relapse.”

At RGCC, we’re pioneering personalised medical testing and offer a range of clinically validated methods for cancer diagnosis, including ctDNA screening.

Our Oncotrail RGCC and Oncotrace RGCC and liquid biopsy tests can identify circulating tumour cells in a patient sample to accurately detect and diagnose certain forms of cancer and track the development of secondary cancers or tumours.

For those with a confirmed cancer diagnosis, Oncocount RGCC can accurately identify the presence of circulating tumour cells (CTCs), a powerful biomarker that can act as an early warning sign that cancer is returning.

You can learn more about the full range of RGCC tests here.

You can read the full paper, ctDNA guiding adjuvant immunotherapy in urothelial carcinoma, here.