Often xenografts or subcutaneous tumors in small rodents are used in oncology research. Traditionally their volume growth has been monitored by using a mechanical caliper. Recently technological evolution and the increase in computing power have facilitated the development of new devices such as the Peira TM900, https://www.peira.be/measuring-device-oncological-tumor-research . It is a lightweight handheld instrument that makes a direct 3D measurement of the tumor volume. It does so by acquiring a stereoscopic image and reconstructing the 3D shape of the tumor. Therefor it allows a direct 3D capture of the volume. A tumor image, its 3D shape and all geometrical data are automatically calculated and stored. The system includes database, data management and processing software and can be complemented with a weight scale.