The early symptom of a "silent killer" cancer that could be hiding in your stool

The pancreas is a vital organ that works to help digest food and regulate hormones, so when something goes wrong there, the consequences can be devastating. In this sense, pancreatic cancer has been nicknamed the "silent killer" because it is difficult to detect in its early stages, and by the time most patients experience clear symptoms, the disease is in an advanced stage where treatment options are limited. Experts Falk Hildebrand, a bioinformatics researcher, and Daisuke Suzuki, a PhD candidate in gut microbiome at the Quadram Institute (UK), have argued in an article published in The Conversation the key role that gut bacteria play in detecting this type of cancer.

The most common form of this cancer—around 90%—is called pancreatic ductal adenocarcinoma , which develops in the duct that connects the pancreas to the small intestine (pancreatic duct). As the researchers explain, "When tumors form here, they can block the flow of digestive enzymes, causing problems with energy metabolism that make patients feel chronically tired and ill ."

However, these symptoms are often subtle and are often overlooked or attributed to other causes, making it difficult to identify as pancreatic cancer.

In response to this situation, a method for early detection of this cancer has emerged thanks to fecal samples , Hildebrand and Suzuki point out. "While analyzing feces may seem like an unlikely method for diagnosing cancer, scientists are discovering that our waste contains valuable information about our health," they point out.

This is a noninvasive procedure that allows us to see what's happening inside the body, and its approach has been validated in studies conducted in several countries, including Japan, China, and Spain. Researchers highlight the latest breakthrough from an international study conducted in 2025 involving researchers from Finland and Iran "whose objective was to examine the relationship between gut bacteria and the development of pancreatic cancer in different populations."

To do this, they collected stool samples and analyzed bacterial DNA with "surprising" results , they note, since patients suffering from pancreatic cancer "showed reduced bacterial diversity in their intestines, with certain species enriched or decreased compared to healthy individuals."

These types of advances are also being applied to study other types of cancer, such as colorectal cancer , Falk Hildebrand and Daisuke Suzuki note in their article. "The two-way interactions between cancer and bacteria are particularly fascinating: not only can certain bacterial profiles indicate the presence of a disease, but the disease itself can alter the gut microbiome, as we previously demonstrated in Parkinson's disease, creating a complex web of cause and effect that researchers are still unraveling," they say.

Both researchers maintain that "we are still in the early stages of applying these findings to clinical practice," but are optimistic about what has been achieved so far: "The possibility of detecting this silent killer before it becomes fatal could transform the outcomes for thousands of patients ," they conclude.