ICD 10 Coding Alert

Question: I’m trying to determine the appropriate ICD-10-CM code for a patient who has had a lumpectomy. There only seem to be ICD-10-CM Z codes for acquired absence of breasts, which would seem to imply removal of the entire breast. How would you code this for a patient who has had a lumpectomy? Or a partial mastectomy? Should I use an N63.- code, which allows me to specify where the lump was?

AAPC Forum Participant

Answer: In this situation, you should not use an N63.- (Unspecified lump in breast) code. Even though these codes allow you to add appropriate characters for the right (4th character 1) and left (4th character 2) breasts and 5th characters for the appropriate quadrant, this specificity doesn’t paint the full picture of what has happened to the patient in this situation.

Instead, you will use the appropriate code from Z90.1- (Acquired absence of breast and nipple). You can use these codes because next to the ICD-10-CM index entry for Absence (of) (organ or part) you’ll see the words “complete or partial.” This implies that the entry under Absence for breast(s) (and nipple(s)) (acquired), covers both full and partial mastectomies and lumpectomies.

You can then specify the breast(s) involved in the procedure by adding a 4th character to indicate laterality, though there are no 5th character options for the Z90.1- codes to specify the quadrant affected.