Breast cancer is usually identified through mammography and subsequent biopsy of any suspicious sites in the breast, but approximately 70 to 80 percent of biopsies are negative, according to the American Cancer Society. A recent study showed that, when used as an adjunct to mammography, an optical coherence tomography (OCT) scanner improved breast cancer diagnosis.Researchers at Hôtel-Dieu Hospital and at Royal Victoria Hospital, both in Montreal, and at Massachusetts General Hospital in Boston used a near-IR laser-based OCT scanner from Advanced Research Technologies Inc. of Saint-Laurent, Quebec, Canada. The device noninvasively scans and reconstructs a 3-D image of the breast using the extinction coefficients of chromophores naturally found there.The clinical trial consisted of 108 pre- and post-menopausal women, aged 31 to 74. After mammography, patients with lesions underwent a biopsy. The results included only patients with available biopsy results and without suspicious areas outside the scanned region. For the remaining 71 patients, biopsy results indicated that 29 were healthy, 17 had malignant tumors, and 25 had benign tumors. The OCT machine scanned both breasts using a window of approximately 100 cm2.At Photonics West in January, Mario Khayat of Advanced Research Technologies presented results from the study. The OCT scanner detected breast cancer with a sensitivity of 88.2 percent and a specificity of 88 percent. These values are as good as or better than those achieved by existing imaging modalities used for diagnosis after mammography. Future work will include fine-tuning the scanner’s performance, developing guidelines for radiologists and evaluating the scanner in other aspects of the clinical process such as screening and monitoring. Additionally, future clinical trials will assess whether the scanner can improve breast cancer treatment in cases in which other imaging modalities are not recommended.