The biomedical imaging of metastatic
breast cancer, especially in lymphatic and lung
metastasis, is highly significant in
cancer staging as it helps assess disease prognosis and treatment. Using an
albumin-
indocyanine green dual-modal nanoprobe developed in our laboratory, in vivo fluorescence imaging and photoacoustic imaging of metastatic
breast cancer tumors were performed separately. Fluorescence imaging at the near-infrared window features high imaging sensitivity but is generally limited by a low imaging depth. Thus,
tumors can only be observed in situ whereas
tumor cells in the lymph nodes and lung cannot be imaged in a precise manner. In contrast, photoacoustic imaging often helps overcome the limitations of imaging depth with high acoustic spatial resolution, which could provide complementary information for imaging
cancer metastases. Ex vivo fluorescence and photoacoustic imaging were also performed to verify the
tumor metastatic route. This study may not only provide insights into the design of dual-modal nanoprobes for
breast cancer diagnosis but may also demonstrate the superiority of combined fluorescence imaging and photoacoustic imaging for guiding, monitoring, and evaluating lymphatic and lung metastatic stages of
breast cancer with a high imaging specificity as well as sensitivity.