Files with .DCM extension represent a digital image that stores medical information of patients such as MRIs, CT scans, and ultrasound images. DCM files use DICOM (Digital Imaging and Communications in Medicine) image file format and can include patient’s information for reference. It was developed by the National Electrical Manufacturers Association (NEMA) and was meant to standardize the imaging file format for distribution and viewing of medical images.
The XLTM file extension represents files that are generated by Microsoft Excel as Macro-enabled template files. XLTM files are similar to XLTX in structure other than that the later doesn't support creating template files with macros. Such template files are used to generate and set the layout, formatting, and other settings along with the macros to facilitate creating similar XLSX files then.
You can also convert DCM into many other file formats. Please see the complete list below.