C61
BillableMalignant neoplasm of prostate
Last updated: FY2026 ICD-10-CM (Oct 1, 2025 – Sep 30, 2026) | CMS-HCC V28 (100% phase-in, PY2026)
Is C61 an HCC code?
Yes. C61 maps to Prostate, Breast, and Other Cancers and Tumors under the CMS-HCC V28 risk adjustment model (and Breast, Prostate, and Other Cancers and Tumors 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 C61
For C61to 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 C61 during that encounter — not just copy-forwarded from a problem list.
What This Code Means
C61 is the ICD-10-CM diagnosis code for malignant neoplasm of prostate. Cancer that starts in the prostate gland, which is part of the male reproductive system. This is one of the most common cancers in men. C61 sits in the ICD-10-CM chapter for neoplasms (c00-d49), within the section covering malignant neoplasms of male genital organs (c60-c63).
Under the CMS-HCC V28 risk adjustment model, C61 maps to Prostate, Breast, and Other Cancers and Tumors (HCC 23) with a community, non-dual, aged base RAF weight of 0.186. Under the older CMS-HCC V24 model, C61 maps to Breast, Prostate, and Other Cancers and Tumors (HCC 12) with a community, non-dual, aged base RAF weight of 0.150. 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.
C61 is the parent code for prostate cancer; always check for fifth or sixth character extensions that specify the histological type (e.g., C61.9 for unspecified) or laterality if applicable. Because C61 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 C61 sourced directly from the CMS-HCC risk adjustment model files and the CMS ICD-10-CM code set.
Coding Tips
- •C61 is the parent code for prostate cancer; always check for fifth or sixth character extensions that specify the histological type (e.g., C61.9 for unspecified) or laterality if applicable
- •Verify documentation includes staging information (TNM stage) and histology type, as these may be coded separately with additional codes from the C80-C97 range for better specificity and treatment planning
Clinical Significance
Prostate cancer is one of the most common cancers in men and a high-volume risk adjustment code. It is critical to distinguish active prostate cancer from personal history of prostate cancer (Z85.46), as the coding and RAF implications are vastly different. Active disease must be supported by ongoing treatment, rising PSA, or documented recurrence. Watchful waiting and active surveillance still qualify as active disease.
Documentation Requirements
- ✓Pathology confirming adenocarcinoma or other histologic type of prostate cancer
- ✓Gleason score or Grade Group
- ✓TNM staging or clinical stage
- ✓PSA level and trend
- ✓Current treatment status: active treatment, active surveillance, watchful waiting, or post-treatment monitoring
- ✓Documentation distinguishing active cancer from personal history
Excludes 1 — Do NOT code together
- malignant neoplasm of seminal vesicle (C63.7)
Use Additional Code
Commonly Confused Codes
- •Z85.46 — Personal history of prostate cancer; use when treatment is complete with no evidence of disease
- •D07.5 — Carcinoma in situ of prostate (prostatic intraepithelial neoplasia); not invasive cancer
- •N40.0-N40.1 — Benign prostatic hyperplasia; entirely different condition
- •D40.0 — Neoplasm of uncertain behavior of prostate; use when histology is inconclusive