Table 1.

Summary of spectroscopic photoacoustic imaging signals of total hemoglobin, oxygen saturation, and lipid content in four histologies (normal, hyperplasia, ductal carcinoma in situ, and invasive carcinoma) in a transgenic mouse model of breast cancer development.

Histology	Total Hemoglobin ± SEM (a.u.)	Oxygen Saturation ± SEM (%)	Lipid Content ± SEM (a.u.)
Normal	527.4 ± 20.5	35.5 ± 0.6	75.4 ± 3.4
Hyperplasia	590.5 ± 42.3	50.6 ± 1.9 *	64.5 ± 6.6
Ductal Carcinoma In situ	472.2 ± 9.1 *^	43.0 ± 0.9 *^	60.4 ± 2.5 *
Invasive Carcinoma	477.9 ± 14.0 *^	46.2 ± 1.1*'	55.5 ± 2.2 *

*Statistically significant difference (P < 0.01) as compared to normal. ^Statistically significant difference (P < 0.01) as compared to hyperplasia. 'Statistically significant difference (P< 0.01) as compared to ductal carcinoma in situ.