Currently there is no support for 4D data from dicom files in the labeler apps. This might be supported in a future release.
In the MATLAB R2021b release, the collection of 2D dicom files can be imported into the Image Labeler app.
If you are working on releases prior to R2021b, a possible workaround for this can be to read the collection of 2D dicom files into an image datastore as described in the following documentation and then label the individual images using the Image Labeler app.
For more details about the Image Labeler app, please refer to the following documentation.