Nucs has been something which three different fields have traditionally been involved with: radiologists, patholgists, and endocrinologists. The latter two are not really involved anymore, and have been replaced by those who specialize only in nucs.
Thus, you can be a board certified diagnostic radiologist with a fellowship in nuclear radiology (1 yr), or you can train in nuclear medicine (separate residency). The nuclear radiologist is more versatile in the job market...
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