Thirty four studies with 1,913 participants (including 577 healthy volunteers) were included in the review.
Results suggested that haemoglobin concentration in breast lesions was approximately twice that in background tissue, but did not support a difference in oxygen saturation.
Lesion detectability (based on contrast with respect to background properties) following retrospective comparison with x-ray mammography could be determined for 212 lesions; 179 of these lesions were detectable in at least one optical mammography view and the authors, therefore, reported that approximately 85% of lesions were detectable by optical mammography.
Only one article provided sensitivity and specificity values for the ability of diffuse optical imaging to detect malignancy based on spectroscopic data (two dimensional nomogram of oxygen desaturation versus blood volume). This study included 166 participants, 44 with confirmed malignancy and the remainder classified as non-cancer patients, and reported a sensitivity of 96% and a specificity of 93%.