Oncology & Hematology Coding Alert

Question: We reported 12 units of 77300 and have the documen­tation to support it, but the payer denied part of the charge. Can you advise?

Codify Subscriber

Answer: The descriptor for 77300 (Basic radiation dosimetry calculation, central axis depth dose calculation, TDF, NSD, gap calculation, off axis factor, tissue inhomogeneity factors, calculation of non-ionizing radiation surface and depth dose, as required during course of treatment, only when prescribed by the treating physician) refers to a basic dosimetry calculation, but doesn’t indicate how many units you can report. However, each port typically requires a calculation. Gap and off-axis calculations also merit their own 77300 charge, and if the patient requires a new calculation during treatment, because of weight change, for example, you may code 77300 again.

Payer policies vary widely on how many units you can report for this code, while other insurers want you to report each instance of 77300 on separate line items with modifier 76 (Repeat procedure or service by same physician or other qualified health care professional) appended. However, CMS’ medically unlikely edits limit the number of units for this code to ten, which probably explains why you got paid for part of your charges (likely the first ten units) and not all of the charges (probably the remaining two units).

If you receive denials for multiple units, be sure to ask your payer for its policyin writingfor this code so you’ll know how to report it and be prepared for limitations in reimbursement for next time.