C82.66
BillableCutaneous follicle center lymphoma, intrapelvic lymph nodes
Last updated: FY2026 ICD-10-CM (Oct 1, 2025 – Sep 30, 2026) | CMS-HCC V28 (100% phase-in, PY2026)
Is C82.66 an HCC code?
Yes. C82.66 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 C82.66
For C82.66 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 C82.66 during that encounter — not just copy-forwarded from a problem list.
What This Code Means
C82.66 is the ICD-10-CM diagnosis code for cutaneous follicle center lymphoma, intrapelvic lymph nodes. A type of non-Hodgkin lymphoma affecting the skin and follicle center cells in the lymph nodes within the pelvis. C82.66 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, C82.66 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, C82.66 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 (within pelvis) lymph node involvement is clearly documented. Because C82.66 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 C82.66 sourced directly from the CMS-HCC risk adjustment model files and the CMS ICD-10-CM code set.
Coding Tips
- •Verify intrapelvic (within pelvis) lymph node involvement is clearly documented
- •Distinguish from other pelvic lymphomas by confirming cutaneous follicle center origin
Clinical Significance
Cutaneous follicle center lymphoma involving intrapelvic lymph nodes represents a deeper spread pattern that is atypical for a primary cutaneous lymphoma. Intrapelvic nodal involvement (iliac, obturator, presacral nodes) suggests the disease may have extended beyond typical regional drainage and should prompt reconsideration of whether the primary cutaneous designation is accurate. Clinical staging and multidisciplinary discussion may be warranted.
Documentation Requirements
- ✓Skin biopsy confirming cutaneous follicle center lymphoma origin
- ✓Cross-sectional imaging documenting intrapelvic lymph node involvement
- ✓Clinical justification for maintaining primary cutaneous classification
- ✓Distinction between intrapelvic and inguinal lymph node groups on imaging
- ✓Complete staging 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: Inguinal nodes are superficial; intrapelvic (iliac) nodes are deep
- •C82.56 — Diffuse follicle center lymphoma, intrapelvic lymph nodes: Systemic disease without cutaneous origin
- •C82.86 — Other types of follicular lymphoma, intrapelvic lymph nodes: Different follicular subtype