C88.00
BillableWaldenström macroglobulinemia not having achieved remission
Last updated: FY2026 ICD-10-CM (Oct 1, 2025 – Sep 30, 2026) | CMS-HCC V28 (100% phase-in, PY2026)
Is C88.00 an HCC code?
Yes. C88.00 maps to Breast, Prostate, Colorectal and Other Cancers and Tumors under the CMS-HCC V28 risk adjustment model (and Other Significant Endocrine and Metabolic Disorders under V24).
HCC Category Mapping
RAF weights shown are the community, non-dual, aged base weights from the CMS risk adjustment model file. Actual per-patient RAF contribution depends on member segment, interactions, and the model year used by the payer. V28 is the CMS-HCC model phased in over payment years 2024–2026; V24 remains in use during the transition and for historical data.
MEAT Criteria for C88.00
For C88.00 to count as a valid HCC diagnosis in a given encounter, the provider's documentation must show MEAT: Monitor, Evaluate, Assess, or Treat. A diagnosis from a prior year does not carry forward automatically — it has to be re-documented and supported each calendar year.
- MMonitor: signs, symptoms, disease progression, or lab trending documented in the note
- EEvaluate: test results, medication response, or physical findings reviewed by the provider
- AAssess: explicit mention in the assessment or plan with acknowledgment of status
- TTreat: medication, referral, procedure, therapy, or counseling tied to the diagnosis
Only one of M/E/A/T is required to support the code, but the documentation must be specific enough to show that the provider actually addressed C88.00 during that encounter — not just copy-forwarded from a problem list.
What This Code Means
C88.00 is the ICD-10-CM diagnosis code for waldenström macroglobulinemia not having achieved remission. A rare blood cancer where abnormal plasma cells produce excessive immunoglobulin M protein, and the disease has not responded adequately to treatment. C88.00 sits in the ICD-10-CM chapter for neoplasms (c00-d49), within the section covering malignant neoplasms of lymphoid, hematopoietic and related tissue (c81-c96).
Under the CMS-HCC V28 risk adjustment model, C88.00 maps to Breast, Prostate, Colorectal and Other Cancers and Tumors (HCC 21) with a community, non-dual, aged base RAF weight of 0.545. Under the older CMS-HCC V24 model, C88.00 maps to Other Significant Endocrine and Metabolic Disorders (HCC 23) with a community, non-dual, aged base RAF weight of 0.230. V28 is the CMS-HCC risk adjustment model that reached 100% phase-in for payment year 2026, replacing V24 which was used during the PY2024–PY2025 transition.
Distinguish between remission (C88.01) and non-remission status based on clinical response to therapy. Because C88.00 maps to a payment HCC, the provider's documentation must satisfy MEAT criteria (Monitor, Evaluate, Assess, or Treat) for the encounter to count toward the patient's Medicare Advantage risk adjustment score. When documentation is ambiguous, coders should issue a provider query rather than assume the highest-specificity variant.
HCC Buddy maintains structured V28 and V24 mapping, RAF weights, and MEAT documentation criteria for C88.00 sourced directly from the CMS-HCC risk adjustment model files and the CMS ICD-10-CM code set.
Coding Tips
- •Distinguish between remission (C88.01) and non-remission status based on clinical response to therapy
- •Document laboratory findings including serum protein levels and immunoglobulin M quantification
Clinical Significance
Waldenstrom macroglobulinemia (lymphoplasmacytic lymphoma) is an indolent B-cell neoplasm characterized by bone marrow infiltration by lymphoplasmacytic cells producing monoclonal immunoglobulin M. The elevated immunoglobulin M can cause hyperviscosity syndrome with neurologic symptoms, bleeding, and visual disturbances. Non-remission status indicates ongoing disease requiring active management of both the neoplasm and its immunoglobulin M-related complications.
Documentation Requirements
- ✓Documentation must include confirmation through bone marrow biopsy showing lymphoplasmacytic infiltrate and serum protein electrophoresis demonstrating the immunoglobulin M monoclonal spike.
- ✓Immunoglobulin M quantification, viscosity levels if symptomatic, hemoglobin, treatment regimen, and non-remission status must be documented.