C91.00

HCC Category Mapping

What This Code Means

A fast-growing blood cancer affecting young white blood cells that has not responded to treatment or achieved remission.

Coding Tips

• •Acute lymphoblastic leukemia (ALL) is primarily a pediatric cancer; note patient age in documentation
• •Remission status must be explicitly documented; do not assume based on treatment alone

Clinical Significance

Acute lymphoblastic leukemia (ALL) is a rapidly progressive malignancy of lymphoid precursor cells that infiltrates the bone marrow, peripheral blood, and potentially the central nervous system and other organs. While predominantly a pediatric disease, adult ALL carries a worse prognosis. Non-remission status indicates the disease is refractory to initial induction therapy, which is associated with very poor outcomes requiring alternative treatment strategies.

Documentation Requirements

• ✓Documentation must include bone marrow biopsy with blast percentage, immunophenotyping (B-cell versus T-cell lineage), cytogenetic and molecular studies (particularly Philadelphia chromosome status), cerebrospinal fluid analysis, treatment protocol, response assessment, and explicit non-remission status.
• ✓Risk stratification must be recorded.

Commonly Confused Codes