C82.55
BillableDiffuse follicle center lymphoma, lymph nodes of inguinal region and lower limb
Last updated: FY2026 ICD-10-CM (Oct 1, 2025 – Sep 30, 2026) | CMS-HCC V28 (100% phase-in, PY2026)
Is C82.55 an HCC code?
Yes. C82.55 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 C82.55
For C82.55 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 C82.55 during that encounter — not just copy-forwarded from a problem list.
What This Code Means
C82.55 is the ICD-10-CM diagnosis code for diffuse follicle center lymphoma, lymph nodes of inguinal region and lower limb. This is a type of blood cancer (lymphoma) that starts in the lymph nodes located in the groin and upper leg area. The cancer cells grow slowly and spread throughout the lymph node tissue in that region. C82.55 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, C82.55 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, C82.55 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 the specific anatomical site (inguinal region and lower limb) is documented in the pathology report before assigning this code, as lymphoma site specificity is critical for accurate coding. Because C82.55 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 C82.55 sourced directly from the CMS-HCC risk adjustment model files and the CMS ICD-10-CM code set.
Coding Tips
- •Verify the specific anatomical site (inguinal region and lower limb) is documented in the pathology report before assigning this code, as lymphoma site specificity is critical for accurate coding
- •Ensure the histology is confirmed as diffuse follicle center lymphoma (not nodular or other variants) and that the stage/grade information is documented separately for complete coding
Clinical Significance
Diffuse follicle center lymphoma involving inguinal and lower limb lymph nodes typically presents as painless groin lymphadenopathy. Inguinal lymph node involvement must be differentiated from reactive inguinal adenopathy (which is common) and metastatic disease from genital, lower extremity, or anorectal malignancies. Lower limb lymph node involvement can cause dependent edema and should prompt evaluation for deep venous thrombosis as a concurrent complication.
Documentation Requirements
- ✓Pathology confirming diffuse follicle center lymphoma histology
- ✓Documentation of inguinal and/or lower limb lymph node involvement
- ✓Laterality (right, left, or bilateral)
- ✓Imaging documenting lymph node size and distribution
- ✓Assessment for lower extremity edema or deep vein thrombosis
- ✓Staging documentation including assessment of other nodal and extranodal sites
Commonly Confused Codes
- •C82.65 — Cutaneous follicle center lymphoma, lymph nodes of inguinal region and lower limb: Cutaneous type has primary skin involvement; confirm histologic subtype
- •C82.56 — Diffuse follicle center lymphoma, intrapelvic lymph nodes: Inguinal nodes are superficial and external to the pelvis; intrapelvic nodes (iliac chains) are internal — anatomic distinction is critical
- •C82.85 — Other types of follicular lymphoma, lymph nodes of inguinal region and lower limb: Use only when the specific type is not diffuse follicle center