Giant Pathological Spectral Imaging (GPSI) systems have potential to rapidly screen H&E stained tissues for cancer diagnosis. The system provides, for the first time, rapid acquisition of spectral information for each pixel. This information can be processed and allows to identify cancer cells and tissues. Therefore, it can help the pathologists to overcome the increasing demand for screening a large number of slides, whereas negating decline in number of pathologist. The fact that the system retains the benefits of ‘Gold standard’ H&E staining to quantifiably assesses giant samples for better diagnostic confidence.