The CERN Large Hadron Collider (LHC) ALICE detector is undergoing a major upgrade in the Second Long Shutdown of the LHC in 2019–2020. During this upgrade, the innermost detector, the Inner Tracking System, will be completely replaced by a new detector which is built from the ALPIDE sensor. In the Bergen proton computer tomography (pCT) collaboration, we decided to apply these sensors for medical applications. They can be used for positioning in hadron therapies due to their good position resolution and radiation tolerance. Dose planning of hadron therapy is calculated currently from photon CT measurements, which results in large uncertainties in the planning and therefore in a necessary enlargement of the treatment area. This uncertainty can be reduced by performing the CT scan using protons. The current contribution shows the development of a sampling calorimeter built from the ALPIDE detector for proton CT measurements and describes the state of the project.
