The identification and differentiation of tissues forms the basis of surgical therapy. Intraoperative tissue differentiation, together with imaging procedures and histopathological and laboratory chemical diagnostics, is one of the various scenarios that influence the decision on therapy. In addition to improved diagnostics, the minimization of surgical trauma during complete tumor removal (R0 resection) remains an essential goal of the further development of surgical methods. Especially in oncology when performing complete tumor resection, new medical technologies enable the clear identification of tumor tissue and its specific differentiation from surrounding healthy tissue in all dimensions allowing for a minimization of damage to the surrounding tissue while preserving functional tissue structures. A reliable differentiation between healthy and malignant tissue is provided by the histopathological examination of the resected tissue, which also guides the intraoperative decision making process when using frozen section diagnostics and represents the gold standard of today. Simultaneously, there is potential to reduce the time and tissue damage.