Cancer-sniffing pets: what is the secret?

The media carry stories of patients who, thanks to early diagnosis of malignancy, claim to have been saved by their cancer-sniffing pets. It is established that the brain of a dog features a wide olfactory cortex, compared to that of humans, where the visual cortex predominates. The cat also possesses an acute sense of smell, due to its well-developed olfactory bulb and a large surface of olfactory mucosa. A series of diagnostic hallmarks of malignancy have been defined, among which tumor necrosis. It is a form of hypoxic death resulting in an accumulation of cell debris and decomposing tissue. It is well known that the decomposition process produces foul-smelling molecules, such as cadaverine and putrescine. Given their remarkable sense of smell, it is more than likely that some pets are able to detect on themselves and in their owner’s body the odor of tumor necrosis deriving from aggressive cancers.

Cancer-sniffing pets; Early diagnosis of malignancy; Tumor necrosis

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