Urinary volatile terpenes analyzed by gas chromatography-mass spectrometry to monitor breast cancer treatment efficacy in mice.

Urinary volatile terpene (VT) levels are significantly altered with induced models of breast cancer in mice. The question arises whether VTs can detect efficacy of anti-tumor treatments. BALB/c mice were injected with 4T1.2 murine tumor cells in the mammary pad or iliac artery to model localized breast cancer and induced bone metastasis. The effect of two dopaminergic anti-tumor agents was tested by conventional histology and altered VT levels. The headspace of urine specimens was analyzed by gas chromatography-mass spectrometry. In the localized model statistical significance (p < 0.05) was identified for 26% of VTs and in the metastasis model, 19% of VTs. The authors discovered separate VT panels classifying localized/control (area under the curve (AUC) = 1.0), and metastasis/control (AUC = 0.98). Treatment samples were tested using these panels and showed that mice treated with either agent were statistically significantly different than cancer samples, which is consistent with conventional analysis.