The CAP began discussions with UnitedHealthcare in early March regarding its policy that establishes the maximum frequency per day for services, including IHC. The insurer has stated it lowered the number of units for IHC code 88342 effective January 1, 2014, based on its understanding of the 2014 American Medical Association Current Procedural Terminology (AMA CPT) code descriptor. United will now only pay one unit per patient, per day, of the IHC code 88342 unless claims are submitted with modifiers -59 or -91. The CAP has stated that this is an incorrect interpretation of CPT guidelines for the service, and it is working with United to address.

AMA CPT states 88342 is billed for each separately identifiable antibody per block, cytologic preparation, or hematologic smear; first separately identifiable antibody per slide.