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Blog February 21, 2018

By Lynn Thornton, RHIA, CCS

Procedure Review for Pro Fee Coders

There is confusion among professional fee coders in regard to the coding of Lymphazurin Blue Injection during sentinel node biopsy for breast procedures. This is a procedure that is frequently performed, and audit results show it is associated with a high potential for error.

What is Lymphazurin Blue: Lymphazurin blue is a blue dye. It is also known as Isosulfan blue and it is classified as a diagnostic agent for lymphatic visualization. Most importantly, it is not a radioactive tracer.

The CPT code that is commonly, and errantly, assigned for this service is as follows:


CPT code 38792 is for the injection of a radioactive tracer.  This service is generally performed in the ancillary department by a radiologist prior to a patient being taken to the operating room for a sentinel node biopsy by the surgeon. Infrequently, the tracer may be injected by the surgeon.  Coders will need to carefully review the documentation to determine the site of service for this procedure.  Professional fee coders may only code and report the services personally provided by the surgeon/midlevel.

The biopsy service is commonly performed in conjunction with an injection of a blue dye, Lymphazurin Blue and mapping. Mapping occurs after the injection of Lymphazurin blue. During this service the surgeon massages the area of the injection for a few minutes. This assists in dispersing the dye through the axillary lymphatics.

Documentation Review: The following documentation is typical of what is seen in these procedures:

PROCEDURES PERFORMED: Left axillary lymphatic mapping, left injection of Lymphazurin blue dye for sentinel node imaging and left deep axillary sentinel node biopsy if necessary.

DESCRIPTION OF PROCEDURE: The patient was brought to the operating room, placed in supine position, and placed under general laryngeal mask anesthesia. The left breast and axilla were prepped and draped in a sterile manner. Then 2 mL of Lymphazurin blue were injected intradermally and massaged for 5 minutes.

The above documentation supports the coding of the following CPT code 38900.


CPT Instructional Notes:  CPT has provided instructional notes below CPT code 38792 as well as 38900.  These instructional notes direct the coder to do as follows:


For purposes of demonstration the critical elements of these descriptors were underlined.

The code descriptors also clarify the intent of the service as shown above.

Root Cause of the Error:  A failure to review the instructional notes could lead to coder error.  Coder error may also occur due to coders mistaking Lymphazurin blue for a radioactive tracer.

*WRVU Impact of Error:  The wRVU values for 2018 for these two procedure codes on the CMS MPFS are listed below.  For each error of this type the surgeon would be losing 2.0 wRVU’s and this is prior to multiple procedure discounting.  This is a significant variance and many surgeons are keenly aware of what wRVU’s should be awarded for services performed.  Over an extended period of time, this could amount to a substantial variance in cumulative wRVU’s.


Note:  CPT code 38900 is an add on code and is not subject to multiple procedure discounting.

Modifier 51 Multiple Procedure is not to be appended to this code

*wRVU-“work relative value unit” structure for compensation purposes

Best Practice in Coding:  Professional fee coding is a position that requires a coder employ critical thinking at all times. Available resources should always be consulted prior to assigning a code when there is an unknown. Never guess as to what a drug, treatment, condition and/or surgical procedure is. The risk of an error is just too high. Repeated errors on a Professional Fee Coders part not only results in a loss of wRVU’s for service performs, it also erodes the physicians trust in the coder.


  • NIH.Gov Lymphazurin blue
  • AMA CPT Manual 2018
  • CMS MPFS 2018