Pathology/Lab Coding Alert

You Be the Coder:

Focus ER+ Coding

Published on Wed Apr 12, 2023

Question: I have a pathology report that just indicates, “breast tumor tissue ER 2+.” What are the appropriate procedure and diagnosis codes?

Arkansas Subscriber

Answer: Because the report lists the estrogen receptor (ER) finding numerically, as ER 2+, the appropriate procedure code would be 88360 (Morphometric analysis, tumor immunohistochemistry [eg, Her-2/neu, estrogen receptor/ progesterone receptor],quantitative or semiquantitative, per specimen, each single antibody stain procedure; manual) or 88361 (... using computer-assisted technology). The difference in the two codes depends on whether the pathologist counts/estimates the number of stained cells manually or using a computer to help assess the slide. The numerical, but not exact (percentage) finding indicates that the test in this case is semiquantitative.

A semiquantitative immunohistochemistry ER tissue exam typically reports one of the following “scores:”

0 for no receptors found
1+ for a small number of receptors found
2+ for a medium number
3+ for a large number

The American Society of Clinical Oncology (ASCO) and the College of American Pathologists (CAP) recommend designating a tumor as ER+ if at least one percent of the cells examined test positive. Using that metric, you would report this evaluation as ER+ using code Z17.0 (Estrogen receptor positive status [ER+]).

Caution: You should not report Z17.0 as a principal diagnosis. You must “code first malignant neoplasm of breast (C50.-),” according to ICD-10-CM instruction.