D48.5 vs D48.6
D48.5 and D48.6 can never be reported together. ICD-10-CM declares them mutually exclusive with an Excludes1 note, meaning the two conditions cannot occur in the same patient — so exactly one of them is correct for any given encounter.
The official note, declared on D48.6
neoplasm of uncertain behavior of skin of breast (D48.5)
D48.5
Neoplasm of uncertain behavior of skin
Billable
- Chapter 2
- Neoplasms
- Section
- D37-D48
Use when the record says
- Neoplasm of uncertain behavior of anal margin
- Neoplasm of uncertain behavior of anal skin
- Neoplasm of uncertain behavior of perianal skin
- Neoplasm of uncertain behavior of skin of breast
Indexed under
- Nevus › bathing trunk
- Tumor › basal cell
- Nevus › pigmented › giant
D48.6
Neoplasm of uncertain behavior of breast
Not billable
- Chapter 2
- Neoplasms
- Section
- D37-D48
Use when the record says
- Neoplasm of uncertain behavior of connective tissue of breast
- Cystosarcoma phyllodes
Indexed under
- Cystosarcoma phyllodes
- Tumor › phyllodes
Excludes1 is not always absolute: where two conditions covered by the note are genuinely unrelated, CMS guidance permits reporting both. Document the reasoning rather than assuming it. More on Excludes1 vs Excludes2 · FY2027