The sentinel lymph node biopsy procedure for melanoma patients can be improved with the use of a minimally invasive sentinel lymph node biopsy device. This thesis shows the early stage designing process of such a device, which can reduce overall tissue damage and opens up possibilities to remove the need for general anaesthesia and therefore the need for an operating room. The design of a device that can locally expand a circular cutting blade is presented. The tests main conclusion is that three rods can indeed be used to actuate variable expansion of such a cutting blade. Subsequently, the blade can be used to cut around different sized target lymph nodes. Furthermore, actuation of this expansion can be achieved through a minimally invasive shaft from outside the patients body. Although further steps of the procedure need to be addressed in order to create a fully functional biopsy device, this thesis shows the potential and feasibility of a locally expanding adaptable cutting blade and provides recommendations for further development steps in the design of a MISLNBD.