Excludes1 pair

D07.1 vs N90.1

D07.1 and N90.1 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 D07.1
moderate dysplasia of vulva (N90.1)
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)
N90.1

Moderate vulvar dysplasia

Billable
Chapter 14
Diseases of the genitourinary system
Section
N80-N98
Use when the record says
  • Vulvar intraepithelial neoplasia [VIN], grade II
Indexed under
  • Dysplasia › vulva › moderate
  • Neoplasia › intraepithelial › vulva › grade II

These two codes sit in different chapters of the Tabular List, which is usually the clearest signal that they describe different underlying processes rather than different degrees of the same one.

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