Researchers have tracked cancer stem cells in patients for the first time.

The idea of cancer stem cells has been a controversial subject for the past several years. The idea suggests that a "small subset of cancer cells" exists that is responsible for the growth and progression of the disease, a University of Oxford news release reported.

The finding suggests that finding a treatment to eradicate the stem cells could help wipe out the cancer completely.

"It's like having dandelions in your lawn. You can pull out as many as you want, but if you don't get the roots they'll come back," first author Doctor Petter Woll of the MRC Weatherall Institute for Molecular Medicine at the University of Oxford, said in the news release.

The researchers tracked malignant cells in the bone marrow of patients suffering from myelodysplastic syndrome (MDS). They used genetic tools to track what cells cancer-driving mutations started in and what cells they later propagated to.

The team found a "rare subset" of MDS cells was able to propagate the tumor and replenish themselves. These cells were the origin of all DNA changes and mutations that drove the disease.

"This is conclusive evidence for the existence of cancer stem cells in myelodysplastic syndromes," Doctor Woll said. "We have identified a subset of cancer cells, shown that these rare cells are invariably the cells in which the cancer originates, and also are the only cancer-propagating cells in the patients. It is a vitally important step because it suggests that if you want to cure patients, you would need to target and remove these cells at the root of the cancer - but that would be sufficient, that would do it."

The researchers hope the finding will lead to the development of more effective cancer therapies in the future.

"We can't offer patients today new treatments with this knowledge. What it does is give us a target for development of more efficient and cancer stem cell specific therapies to eliminate the cancer," Doctor Woll said. "We need to understand more about what makes these cancer stem cells unique, what makes them different to all the other cancer cells. If we can find biological pathways that are specifically dysregulated in cancer stem cells, we might be able to target them with new drugs."