How to Use the New Digital Pathology CPT Codes: CAP Answers Questions

This blog post stems from the webinar "Coming Reimbursement Opportunities for Digital Pathology," hosted by the CAP's Digital and Computational Pathology Committee (DCPC) and presented by Economic Affairs Committee (EAC) and DCPC leaders. It serves as a follow up to the initial announcement of the codes' release and also answers member-submitted questions that could not be addressed during the webinar. Editorial clarifications were made by members of the EAC and DCPC.

In 2022, the CAP successfully advocated for adding 13 new digital pathology Current Procedural Terminology (CPT) codes to the 2023 CPT code set. These add-on CPT codes are used to report additional clinical staff work and service requirements associated with digitizing glass microscope slides for primary diagnosis. The new codes help pathologists, pathology practices, and laboratories using digitization of glass slides to appropriately report these services.

As of January 1, 2023, Category III add-on codes 0751T-0763T may be reported in addition to the appropriate Category I service code when the digitization procedure of glass microscope slides is performed and documented in conjunction with the Category I code for the primary service. Each new add-on CPT code is to be reported (1:1) in combination with its specific corresponding Category I direct service CPT code.

The add-on digital pathology CPT codes are currently classified as Category III codes, which are temporary codes for emerging technologies that allow for data collection associated with the service and have no assigned RVU or established payment. Category III code usage documents the utilization of the service and, thus, the potential need for Category I codification.

The new add-on CPT codes are to be used when digitization has been performed in the process of primary diagnosis. There are a few situations when the new add-on CPT codes should not be utilized. These are when the digitization process is performed:

• Solely for archival purposes (eg, after the Category I service has already been performed and reported)
• Solely for educational purposes
• Solely to validate artificial intelligence algorithms
• Solely for clinical conference presentations (eg, tumor boards or interdisciplinary conferences)

Below are answers to questions collected from CAP member pathologists regarding the add-on CPT codes and their ramifications thus far.

Digital pathology is an element we need to advance our work and take advantage of new opportunities, such as artificial intelligence and the disseminated ability to bring much-needed subspecialty expertise in a timely fashion to all patient populations. Investing in digital pathology can potentially improve and democratize primary diagnosis, which merits reimbursement.

Still, we are also aware that digital pathology can be utilized in ways other than for primary diagnosis. Therefore, to appropriately account for the resource costs in the future valuation of these services, the utilization of digital pathology essential for primary diagnosis must be explicitly specified. The development of additional digital pathology direct diagnosis codes for cytopathology, intraoperative consultation, and potential future applications—such as those combined with emerging AI technologies—are being considered.

Classification as Category III does not preclude future reclassification as Category I; instead, it is a needed step, as Category III code usage is intended to document the need for subsequent Category I codification.

Digital pathology is, unfortunately, in some ways the victim of its many successes. Given its utility in many arenas besides primary diagnosis, third-party payers are concerned that pathologists will seek reimbursement for using digital pathology for purposes other than primary diagnosis. By appropriately using the new add-on digitization CPT codes and pairing this service with the standard CPT codes already acknowledged to be of value in direct patient care to an individual patient, pathologists can demonstrate to the AMA CPT Editorial Panel that digital pathology is being used for primary diagnosis and deserves reimbursement.

The typical lifecycle of a Category III code is 1–5 years. The CAP will advocate for converting the new add-on CPT codes from Category III to Category I as soon as there is evidence of general and widespread use, a requirement for Category I codification. Therefore, we need you [practicing pathologists] to use these Category III codes so that we can justify moving these to Category I, where they can be valued nationally for payment, even if you are only digitizing a portion of your cases.

The 88361 CPT code is used for computer-assisted quantitative immunohistochemistry. Since this requires scanned slides, this CPT code already recognizes the digitization process. Therefore, no additional digital pathology CPT code is needed.

Is the retention period for digitized slides the same as for glass slides?

The retention period for glass slides is set at several levels involving multiple entities. Currently, the retention period for digitized slides is not yet definitively set. The retention of glass slides fulfills all requirements presently. Still, it should be noted that if the glass slide is re-utilized (such as for re-staining or DNA retrieval), the digital slide becomes the reference standard and should be retained for the mandated period.

In general, this panel believes that if one took the time, effort, and expense to digitize slides, planning to retain them long-term would be most beneficial.

Some viewers and archiving systems are file-type agnostic and, therefore, can be considered a viable bridge between scanners/file types. This highlights the need for adherence to standards like DICOM so that interoperability can be more robust. Evidence from the several "hackathons," which challenge vendors of differing scanners, viewing systems, and such to be able to manage diverse file types, would indicate that many systems currently manage these differences while others still struggle. Checking out the results of such live "experiments" with these systems before implementing or purchasing a system would be prudent.

This will necessarily be very dependent on context. If you are in an institution that relies on external consultative expertise, it will lower the time and effort threshold for obtaining consultations, expediting, and potentially improving, care. In that case, it will allow your consulting pathologists to review WSIs remotely, ensuring that they remain cutting edge regarding referrals and thereby increasing the likelihood that your institution will continue to be a referral center for pathology cases and patient referrals.

Whoever prepares the digitized slide images should use the new add-on CPT codes. To avoid improper billing, pathologists billing only the professional component for reviewing the images should not apply these codes.

This distinction looks forward to these services' valuation (and payment). Each of these linked glass-slide services have an implicit number of slides, permitting the valuation of the technical resources required for digitization.

No. Only glass slides digitized for diagnostic purposes have an associated digitization CPT code.

Due to the hard work of the CAP Economic Affairs Committee and the Council on Government and Professional Affairs, the CAP successfully advocated for the incorporation of the new Category III CPT codes to capture the work of slide digitization as the practice of pathology migrates to this platform. However, for our specialty to be ultimately successful in capturing the additional costs of these services, the use of these new codes by all pathology practices is crucial. For more information, including the "Final 2023 Medicare Payment Regulations" webinar, visit the 2023 Digital Pathology Codes page.

The Digital and Computational Pathology Committee is charged with advancing the adoption of digital pathology within the CAP and serving as a respected resource for information and education for pathologists, patients, and the public on the practice and science of digital pathology. This committee reports to the Council on Informatics and Pathology Innovation.