ICD-10 Code C92.42 – Acute promyelocytic leukemia, in relapse (2026): Diagnosis, Symptoms & Billing Guide
2026 ICD-10-CM Diagnosis Code C92.42 – Acute promyelocytic leukemia, in relapse
What it is
C92.42 identifies acute promyelocytic leukemia that has returned after a period of remission. Use it for the relapsed form of this specific acute myeloid leukemia subtype.
Clinical signs
Clinical features vary; refer to documentation. Relapse is usually supported by evidence of recurrent promyelocytes in blood or marrow, with signs consistent with acute leukemia.
When to use this code
Use C92.42 when the record clearly states acute promyelocytic leukemia is in relapse. This applies after prior remission or response, when the provider documents recurrent disease. If the chart only says leukemia without subtype or relapse status, check documentation before coding.
Do not use for
Do not use this code for new, untreated acute promyelocytic leukemia or for leukemia in remission. If the subtype or relapse status is not documented, do not assume C92.42.
Coding tip
Code the relapse only when the provider explicitly links the diagnosis to acute promyelocytic leukemia.