Sentinel node in cancer diagnosis with surgical probes

A probe system has been designed for the accurate location of areas of increased radionuclide uptake. Different types of applications are possible, i.e. when the precise position or even identification of the radionuclide is needed, like in wound investigation. In this paper, we restrict ourselves to a system incorporating two probes, for the identification of “hot” lymph nodes, close to the surface of the body. Axillary lymph node involvement is a major prognostic indicator and treatment planning factor in both melanoma and breast cancer. However, sentinel node localisation is relatively difficult often due to close proximity of the primary tumour. The developed instrument has a very sensitive detector, with good spatial resolution, able to discriminate between primary and scattered radiation. In the first part of the paper the instrument arrangement will be presented, including the two probes, CdTe /CZT and CsI(Tl) coupled to a photodiode. In the second part results will be given, demonstrating the performance of the system.