FY2027
MenuClose
Excludes1 pair

D18.1 vs D21-

D18.1 and D21 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 D21
lymphangioma (D18.1)
D18.1

Lymphangioma, any site

Billable
Chapter 2
Neoplasms
Section
D10-D36
Indexed under
  • Hemolymphangioma
  • Hygroma (congenital) (cystic)
  • Lymphangioendothelioma
  • Lymphangioma
  • Lymphangiomyoma
D21

Other benign neoplasms of connective and other soft tissue

Not billable
Chapter 2
Neoplasms
Section
D10-D36
Use when the record says
  • benign neoplasm of blood vessel
  • benign neoplasm of bursa
  • benign neoplasm of cartilage
  • benign neoplasm of fascia
  • benign neoplasm of fat
  • benign neoplasm of ligament, except uterine
  • benign neoplasm of lymphatic channel
  • benign neoplasm of muscle

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