That is one of the conclusions of a new study published in the journal CANCER. The study also found that a panel of bladder cancer markers can predict which particular cases are at the highest risk for a fatal outcome.

Researchers have known that smoking is one of the most common causes of bladder cancer, but they’ve wondered whether it also affects how the disease progresses. To investigate, researchers analysed the bladder tumours and smoking history of 212 patients recruited through the Los Angeles County Cancer Surveillance Programme between 1987 and 1996.

They found that the bladder cancers that developed in individuals who smoked intensely were more likely to be deadly than bladder cancers that developed in those who never smoked, or who smoked less.

The study also revealed that changes in particular proteins are often present in bladder cancers that have become deadly. “We have identified a panel of nine molecular markers that can robustly and reproducibly predict bladder cancer prognosis independent of standard clinical criteria and smoking history,” said Dr Anirban Mitra from the Keck School of Medicine of the University of Southern California in the United States, a co-author of the study. Patients with alterations in six to nine markers had a very poor outcome, raising the hypothesis that these individuals could have benefited from more aggressive treatments.

Because the number of changes in these proteins was directly proportional to patients’ health outcomes in a progressive fashion, the findings confirm the theory that an accumulation of changes is more important than individual changes in determining the characteristics of a given cancer. The link between smoking intensity and prognosis found in this study points to the incrementally harmful effects of smoking.

“The study’s findings are extremely clinically relevant as bladder cancer is one of the most expensive malignancies to treat,” said the other author, Dr Richard Cote of the University of Miami Miller School of Medicine. “Personalised patient management is urgently needed for this disease as current clinical stratification cannot predict outcomes of individual patients.”

Source: EurekAlert!