While trained animals and humans can detect VOCs, there are limitations: “fatigue, mood swings, and inability to identify specific molecules” can reduce accuracy. That’s why scientists are developing electronic noses (e-noses) to detect cancer reliably.
However, it’s not always the tumor causing the smell. “Diet, medications, microbiota, and smoking habits change the volatilome,” which means strict controls are needed during sample collection. For example, tobacco byproducts like NNAL can interfere with urinary cancer signals.
The immune system also plays a role. Inflammation from tumors triggers enzymes that create smelly aldehydes, which can affect test results. More research is needed to reduce false positives.
Looking Forward:
Validation: “Studies with thousands of participants” are required to confirm accuracy.
Ethics: VOC analysis may reveal other conditions like drug use, raising “smell privacy” concerns.
Equity: It’s vital to ensure that new tests “do not increase gaps” between rich and poor healthcare systems.
🧪 The science is promising—but it must be developed carefully to be safe, accurate, and fair.
