C94.31 Mast cell leukemia, in remission

Billable ICD-10-CM code, FY2026. Acts as a Complication or Comorbidity (CC) as a secondary diagnosis.

Applies from C94 Other leukemias of specified cell type

Excludes1 (never code together)

• leukemic reticuloendotheliosis (C91.4-)
• myelodysplastic syndromes (D46.-)
• personal history of leukemia (Z85.6)
• plasma cell leukemia (C90.1-)

Risk adjustment (HCC)

• CMS-HCC V28: HCC 20 — Lung and Other Severe Cancers
• CMS-HCC V22: HCC 9 — Lung and Other Severe Cancers
• RxHCC V08: HCC 19 — Leukemias and Other Hematologic Cancers
• ESRD V24: HCC 9

MS-DRG index

Defines the logic of DRG(s) 820-822 in MDC 17.

Approximate ICD-9-CM (GEMs)

• 207.81 Other specified leukemia, in remission (approximate)

Code annotations containing back-references to C94.31

Back-references to C94.3

• Type 1 Excludes: D47.02 Systemic mastocytosis ("mast cell leukemia (C94.3-)")
• Type 1 Excludes: D89.4 Mast cell activation syndrome and related disorders ("mast cell leukemia (C94.3-)")

Back-references to C94

• Type 1 Excludes: C76 Malignant neoplasm of other and ill-defined sites ("malignant neoplasm of lymphoid, hematopoietic and related tissue (C81-C96)")
• Type 1 Excludes: D72.8 Other specified disorders of white blood cells ("leukemia (C91-C95)")
• Type 1 Excludes: D72.825 Bandemia ("leukemia (C91.-, C92.-, C93.-, C94.-, C95.-)")
• Code First: M36.1 Arthropathy in neoplastic disease ("leukemia (C91-C95)")
• Code First: N16 Renal tubulo-interstitial disorders in diseases classified elsewhere ("leukemia (C91-C95)")
• Code First: R50.81 Fever presenting with conditions classified elsewhere ("leukemia (C91-C95)")
• Type 1 Excludes: T66 Radiation sickness, unspecified ("leukemia (C91-C95)")
• Code First: Z15.0 Genetic susceptibility to malignant neoplasm (", if applicable, any current malignant neoplasm (C00-C75, C81-C96)")

Nearby codes

• C94.20 Acute megakaryoblastic leukemia not having achieved remission
• C94.21 Acute megakaryoblastic leukemia, in remission
• C94.22 Acute megakaryoblastic leukemia, in relapse
• C94.3 Mast cell leukemia
• C94.30 Mast cell leukemia not having achieved remission
• C94.31 Mast cell leukemia, in remission (this code)
• C94.32 Mast cell leukemia, in relapse
• C94.4 Acute panmyelosis with myelofibrosis
• C94.40 Acute panmyelosis with myelofibrosis not having achieved remission
• C94.41 Acute panmyelosis with myelofibrosis, in remission
• C94.42 Acute panmyelosis with myelofibrosis, in relapse