PROBLEM TO BE SOLVED: To provide a method and a device capable of providing information for determining whether a metastasis of a cancer cell or a cancer tissue is present by specifying an accurate position of a sentinel lymph node and inspecting the sentinel lymph node with high sensitivity and high resolution.SOLUTION: The problem is solved by the device and the method that comprises: a step of superimpose-displaying a visible light image obtained by radiating illumination light on an observation range and first fluorescent image obtained by radiating first excitation light on the observation range by using at least two laparoscopes to confirm the position of the sentinel lymph node a step of irradiating a sentinel lymph node selected from the sentinel lymph nodes the positions of which are confirmed, with second excitation light corresponding to the size of the sentinel lymph node and either one or both of a step of receiving second fluorescent light obtained by radiating the second excitation light to display a second fluorescent image and a step of measuring a fluorescent spectrum from the second fluorescent light obtained by radiating the second excitation light and displaying it.
