C81.26
BillableMixed cellularity Hodgkin lymphoma, intrapelvic lymph nodes
Last updated: FY2026 ICD-10-CM (Oct 1, 2025 – Sep 30, 2026) | CMS-HCC V28 (100% phase-in, PY2026)
Is C81.26 an HCC code?
Yes. C81.26 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 C81.26
For C81.26 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 C81.26 during that encounter — not just copy-forwarded from a problem list.
What This Code Means
C81.26 is the ICD-10-CM diagnosis code for mixed cellularity hodgkin lymphoma, intrapelvic lymph nodes. A type of Hodgkin lymphoma with mixed cellularity affecting lymph nodes inside the pelvis. C81.26 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, C81.26 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, C81.26 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.
Verify intrapelvic location is clearly documented in imaging or pathology reports. Because C81.26 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 C81.26 sourced directly from the CMS-HCC risk adjustment model files and the CMS ICD-10-CM code set.
Coding Tips
- •Verify intrapelvic location is clearly documented in imaging or pathology reports
- •Distinguish from other abdominal lymph node sites
Clinical Significance
Mixed cellularity Hodgkin lymphoma involving intrapelvic lymph nodes represents a moderately aggressive classical Hodgkin lymphoma subtype with significant resource utilization for staging, chemotherapy, and radiation planning. Intrapelvic involvement typically indicates at least stage II disease and may complicate treatment delivery due to proximity to reproductive and urinary organs. Accurate capture is critical for risk adjustment as it reflects ongoing oncologic care needs.
Documentation Requirements
- ✓Pathology report confirming mixed cellularity classical Hodgkin lymphoma histology (Reed-Sternberg cells in mixed inflammatory background)
- ✓Imaging confirmation (CT, PET/CT) specifying intrapelvic lymph node involvement
- ✓Ann Arbor staging designation (I-IV) with substage (A/B) for systemic symptoms
- ✓Current treatment status: active treatment, surveillance, or remission
- ✓Documentation that the condition is being actively managed or monitored during the encounter