A picture archiving communication system for storing, transferring various digital image data in a single or a plurality of hospitals includes a modality (10), a data base (12), a workstation (14) as a display unit, and a network (16) for connecting these components. The modality (10) includes various diagnosis apparatuses for generating medical digital images, such as a film digitizer (18), an angiography apparatus (20), a CT scanner (22), an MRI system (24), a nuclear medicine diagnosis apparatus (26), an ultrasound diagnosis apparatus (28), and an electric endoscope (30). An examination ordering system (32) is connected to the network (16). The workstation (14) outputs computer-aided diagnosis data obtained by analyzing medical image data by means of a computer. This computer-aided diagnosis data includes the location, the type, and the degree of abnormality. In order to alarm an abnormality, the workstation (14) displays a marker pointing the portion of the abnormal portion on the image, a text sentence representing the details of the abnormality. The computer-aided diagnosis data is obtained before its output is requested. The computer-aided diagnosis data is stored in a semiconductor memory (86) until its output is requested.