C96.9
BillableMalignant neoplasm of lymphoid, hematopoietic and related tissue, unspecified
Last updated: FY2026 ICD-10-CM (Oct 1, 2025 – Sep 30, 2026) | CMS-HCC V28 (100% phase-in, PY2026)
Is C96.9 an HCC code?
Yes. C96.9 maps to Breast, Prostate, Colorectal and Other Cancers and Tumors under the CMS-HCC V28 risk adjustment model (and Lymphoma and Other Cancers 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 C96.9
For C96.9 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 C96.9 during that encounter — not just copy-forwarded from a problem list.
What This Code Means
C96.9 is the ICD-10-CM diagnosis code for malignant neoplasm of lymphoid, hematopoietic and related tissue, unspecified. A cancer of the blood-forming and lymph tissues where the specific type has not been identified or documented. C96.9 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, C96.9 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, C96.9 maps to Lymphoma and Other Cancers (HCC 10) with a community, non-dual, aged base RAF weight of 0.675. 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.
Use this code only when the specific type of lymphoid or hematopoietic malignancy cannot be determined from the medical record. Because C96.9 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 C96.9 sourced directly from the CMS-HCC risk adjustment model files and the CMS ICD-10-CM code set.
Coding Tips
- •Use this code only when the specific type of lymphoid or hematopoietic malignancy cannot be determined from the medical record
- •Query the physician if more specific histology or subtype information is available to assign a more specific C96 code
Clinical Significance
This unspecified code represents a malignant neoplasm of lymphoid, hematopoietic, or related tissue where the specific histological type has not been identified. It typically reflects incomplete workup or pending pathology results, and its use should be temporary until a definitive diagnosis is established. Malignancies in this category carry variable prognoses depending on the ultimate subtype identified.
Documentation Requirements
- ✓This code should only be used when pathology results are pending or unavailable
- ✓once specific histology is obtained, the code should be updated to the appropriate specific diagnosis. Document the reason for unspecified status, any pending diagnostic studies, and the clinical presentation. Follow-up encounters should reflect updated pathology findings with a more specific code assignment.