US chemists have identified the odor that emanates from skin cancer, a development that researchers hope will advance diagnosis and treatment of the deadly disease, said a study out Wednesday.

The creation of a "profile" of the chemical odors linked to skin cancer, may lead to a day when diagnoses can be made by waving a scanner over the skin, researchers told the annual conference of the American Chemical Society in Philadelphia, Pennsylvania.

Doctors have already know that skin cancer carries a particular odor, and recent studies have shown that dogs are able to detect tumors because they smell differently than normal skin.

"Researchers have speculated that tumors give off different odors, but we're the first to identify and quantify the compounds involved in skin cancer odors," said chemist Michelle Gallagher, who conducted the study at the Monell Chemical Senses Center in Philadelphia, Pennsylvania.

Gallagher and colleagues analyzed the air above tumor sites in 11 patients diagnosed with basal cell carcinoma, the most common type of skin cancer, and compared the finding with those taken from healthy patients.

They found "a different profile of chemicals above tumor sites relative to healthy skin; the same chemicals are present, but at skin cancer sites some chemicals are increased, while others are decreased compared to healthy individuals."

Around one million new cases of skin cancer are diagnosed each year.The scientists did not reveal the specific chemicals found, but they plan to identify a reliable "odor profile" of all three forms of skin cancer, including squamous cell cancer and melanoma, the deadliest form.

Gallagher said she hoped the findings would "open doors to potential new approaches to skin cancer diagnosis based on the profile of skin odors, hopefully leading to more rapid and non-invasive detection and diagnosis."

Skin cancer is currently diagnosed by taking biopsies of irregular moles or lesions.