Excludes1 pair
C51- vs D07.1
C51 and D07.1 are not coded together. ICD-10-CM declares them mutually exclusive with an Excludes1 note — the two conditions are not expected to occur together, so exactly one of them is normally correct for a given encounter. The Official Guidelines carve out one exception: if the two conditions are clearly unrelated to each other, both may be reported.
The official note, declared on C51
carcinoma in situ of vulva (D07.1)
D07.1
Carcinoma in situ of vulva
Billable
- Chapter 2
- Neoplasms
- Section
- D00-D09
Use when the record says
- Severe dysplasia of vulva
- Vulvar intraepithelial neoplasia III [VIN III]
Indexed under
- Dysplasia › vulva › severe NEC
- Neoplasia › intraepithelial › vulva › grade III (severe dysplasia)
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