C83.34
BillableDiffuse large B-cell lymphoma, lymph nodes of axilla and upper limb
Last updated: FY2026 ICD-10-CM (Oct 1, 2025 – Sep 30, 2026) | CMS-HCC V28 (100% phase-in, PY2026)
Is C83.34 an HCC code?
Yes. C83.34 maps to Lung and Other Severe Cancers 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 C83.34
For C83.34to 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 C83.34 during that encounter — not just copy-forwarded from a problem list.
What This Code Means
C83.34 is the ICD-10-CM diagnosis code for diffuse large b-cell lymphoma, lymph nodes of axilla and upper limb. A type of aggressive blood cancer (diffuse large B-cell lymphoma) affecting lymph nodes in the armpits and upper arms. C83.34 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, C83.34 maps to Lung and Other Severe Cancers (HCC 20) with a community, non-dual, aged base RAF weight of 1.136. Under the older CMS-HCC V24 model, C83.34 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.
Axillary lymph nodes are the primary focus; ensure documentation distinguishes between axillary and other upper limb involvement. Because C83.34 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 C83.34 sourced directly from the CMS-HCC risk adjustment model files and the CMS ICD-10-CM code set.
Coding Tips
- •Axillary lymph nodes are the primary focus; ensure documentation distinguishes between axillary and other upper limb involvement
- •Verify laterality (right vs. left) is documented if clinically relevant for treatment planning
Clinical Significance
Diffuse large B-cell lymphoma of axillary and upper limb lymph nodes is a frequently encountered site presentation. Axillary lymphadenopathy from DLBCL is typically rapidly progressive, unlike the indolent course seen in low-grade lymphomas, making timely diagnosis and treatment initiation critical.
Documentation Requirements
- ✓Pathology confirmation of DLBCL from axillary node biopsy
- ✓Documentation specifying axillary and/or upper limb lymph node involvement
- ✓Laterality (right, left, bilateral)
- ✓Node size measurement and rate of growth if applicable
- ✓Imaging (CT, PET/CT) documenting extent of axillary disease
Commonly Confused Codes
- •C83.14 — Mantle cell lymphoma, axilla/upper limb; different subtype requiring pathology differentiation
- •C83.04 — Small cell B-cell lymphoma, axilla/upper limb; indolent lymphoma with different prognosis
- •C83.31 — DLBCL, head/face/neck; supraclavicular nodes belong to the cervical chain, not axillary
- •C77.3 — Secondary/unspecified malignant neoplasm of axillary lymph nodes; this is for metastatic disease, not primary lymphoma