Dogs may be the future of breast cancer detection.

New research revealed German Shepherds can sniff out breast cancer from clothing that has contacted the breast of a woman with a tumor. The study, which was conducted by the Curie Institute in Paris, found that after six months of training the dogs had a 100 percent success rate diagnosing cancer, according to researchers on Friday.

For the study, researchers collected cloth samples from 31 cancer patients. Using a reward system, the dogs were trained to determine the difference between materials that have been in contact with cancer patients from the regular cloths.

“It is all based on game-playing,” canine specialist Jacky Experton said in a statement.

Dogs would go up to a box with a cloth, and if detected, they would place their muzzle in a cone. In the first found, dogs detected 28 out of the 31 swaths from women with cancer, but in the second trial, the dogs improved to score 100 percent.

Researchers plan to continue the research with a clinical trial with more patients and dogs.

The team said that the research would benefit areas where it is difficult for women to get mammograms, more so than developed countries.

“In these countries, there are oncologists, there are surgeons, but in rural areas often there is limited access to diagnostics,” project leader Isabelle Fromantin said.