Urine biomarker may predict bladder cancer treatment response, study finds

• A new urine-based test can detect minimal residual bladder cancer after surgery and BCG treatment by analyzing tumour DNA in urine.
• The test can distinguish between those likely to be cured by surgery alone, those who could benefit from BCG immunotherapy, and those who do not respond and are at high risk of recurrence.
• Participants with detectable tumour DNA after completing BCG were highly likely to experience cancer recurrence, while those whose tumour DNA cleared had excellent outcomes.
• The approach may enable more personalized treatment by identifying who needs additional therapy, who can safely avoid BCG, and who may require earlier intervention.

Bladder cancer is the sixth most common cancer in the United States, and is the tenth leading cause of cancer death in America.

Approximately 70 to 75% of newly diagnosed bladder cancers are non-muscle invasive bladder cancer (NMIBC). This describes an early stage in which cancer cells are confined to the inner layers of the bladder and have not yet grown into the muscle layer.

Initial treatment typically involves the removal of the tumor. It may then be suitable to receive medications placed directly into the bladder to destroy any remaining cancer cells and reduce the risk of cancer recurrence or becoming more aggressive.

For higher risk NMIBC, a person may receive Bacillus Calmette-Guérin (BCG) immunotherapy. Although effective, BCG therapy can be poorly tolerated and it is difficult to predict how people may respond.

Now, a study published in Cell suggests that a simple urine test may help identify which people with bladder cancer are likely to benefit from BCG immunotherapy and those who will not. The findings could mark a step toward more personalized treatment.