Did some sleuthing in the Oncology Coding Alert and found this:
Thanks to an old National Correct Coding Initiative (NCCI) edit, version 10.2, you can report 78804 and 78803. The edit is important for oncology and nuclear medicine coders because SPECT (single photon emission computed tomography) is the three-dimensional reconstruction of the nuclear medicine scan. The oncologist or nuclear medicine specialist can use SPECT to view a diagnostic study's results.
The code pair combination of whole body and SPECT for either bone imaging or tumor imaging has been a normal part of nuclear medicine imaging for many years. Physicians perform several types of whole-body tumor and SPECT studies, including monoclonal antibody imaging with agents, Bexxar or Zevalin, prostascint imaging, and gallium imaging for malignant disease.
For example: The radiation oncologist uses radiopharmaceutical localization to test radioimmunotherapy agents Zevalin and Bexxar. By using the localization technique, the physician determines whether the radiopharmaceutical will target a patient's tumor or will concentrate in critical organs. For this service you could report 78804. Afterward, the physician performs a SPECT study to increase the specific anatomical localization and augmented lesion count density.
Best bet: Check your carrier's policy on how to submit 78804-78803 claims, because some insurers require modifier 51 (Multiple procedures). Therefore, when you report 78804 and 78803 to these carriers, make sure you attach modifier 51 to one of the codes.
Coders use this modifier when they report multiple procedures. If you assign 51, remember that payers reduce the code's payment by half. That means you should link the modifier to 78803, because this is the lower paying code.