HCC diagnosis codes are Hierarchical Condition Category codes used in Medicare Advantage plans to predict healthcare costs based on a patient’s chronic and severe acute conditions
What is CMS HCC diagnosis?
A CMS HCC diagnosis refers to the Centers for Medicare & Medicaid Services’ Hierarchical Condition Category model used to predict healthcare spending for Medicare Advantage Plan enrollees
Here's the thing: CMS doesn't just hand out money to Medicare Advantage plans. They use the HCC model to figure out who needs more funding based on health risks. The system looks at documented diagnoses—everything must be backed by medical records and reported with ICD-10-CM codes. Only conditions that meet CMS coding guidelines actually count toward risk adjustment. CMS
What does HCC mean after a diagnosis?
HCC stands for Hierarchical Condition Category, a risk-adjustment coding system used to predict future healthcare costs based on a patient’s diagnosed conditions
After you've gotten a diagnosis, HCC coding becomes crucial. Medicare Advantage plans need this info to get paid properly for taking care of patients with complex health needs. Providers code conditions using ICD-10-CM, which then get mapped to HCC codes. Honestly, this is the best approach for making sure plans get funded appropriately for chronically ill patients. CMS Risk Adjustors
How many HCC codes are there in 2020?
In 2020, there were 86 HCC codes used for Medicare Advantage risk adjustment
Those 86 codes come from over 9,700 ICD-10-CM diagnosis codes grouped into clinically meaningful categories. Each HCC represents a set of related diagnoses that predict similar costs. The number hasn't changed much since 2020, though ICD-10-CM codes keep getting updated every year to include new conditions. CMS 2020 HCC Model
What does HCC stand for in cancer?
In cancer, HCC stands for Hepatocellular Carcinoma, the most common type of primary liver cancer
Hepatocellular carcinoma usually shows up in people with chronic liver disease—cirrhosis or hepatitis B/C are common culprits. Other risk factors include heavy drinking, fatty liver disease, and exposure to aflatoxins. It's brutal: this cancer ranks third worldwide for cancer-related deaths. American Cancer Society
What does HCC mean medically?
Medically, HCC refers to Hierarchical Condition Categories, a risk-adjustment system used by CMS to predict healthcare expenditures
This system was created to make sure Medicare Advantage plans get paid fairly when they care for patients with multiple chronic conditions. It uses documented diagnoses to calculate a risk score that reflects expected healthcare needs. Only conditions meeting CMS documentation standards count—nothing gets through on a technicality. CMS Risk Adjustment Overview
What is a good HCC score?
A good HCC risk score is typically less than 1.0, indicating relatively low expected healthcare costs
Scores run from 0.9 to 1.7, with higher numbers meaning more predicted costs due to chronic illness. A score under 1.0 suggests the patient has milder or fewer chronic conditions. Plans with average scores below 1.0 generally receive lower capitation payments. CMS HCC Scoring Memo
How many HCC models are there?
As of 2026, there are two primary HCC risk-adjustment models: CMS-HCC and HHS-HCC
CMS-HCC covers Medicare Advantage enrollees aged 65+ or disabled. The HHS-HCC model, on the other hand, applies to the individual and small group markets under the Affordable Care Act. Each model has different demographic assumptions and coding requirements. ASPE Risk Adjustment Report
What is the difference between CMS-HCC and HHS-HCC?
The CMS-HCC model applies to beneficiaries aged 65+ or disabled, while the HHS-HCC model covers all age groups in the commercial insurance market
| Model | Population | Purpose |
|---|
| CMS-HCC | Medicare Advantage enrollees (age 65+ or disabled) | Adjusts capitation payments based on chronic condition burden |
| HHS-HCC | Individual and small group market (all ages) | Adjusts premiums and payments for ACA-compliant plans |
Both models use ICD-10-CM codes but differ in demographic adjustments and regulatory context. The CMS model is administered by Medicare, while the HHS model is overseen by the Department of Health and Human Services. CMS Risk Adjustment
What is an HCC visit?
An HCC visit is a patient encounter during which Hierarchical Condition Category codes are documented and reported for risk adjustment purposes
For coding to count, diagnoses must be supported by medical records and reported via claims. Providers should make sure all relevant chronic conditions get captured at least once a year. Only diagnoses from face-to-face visits can be used for HCC scoring—chart reviews alone won't cut it. CMS HCC Coding Tips
How many HCC codes are there?
There are 86 HCC codes as of the latest CMS models
These 86 codes represent groups of ICD-10-CM diagnoses that predict similar healthcare costs. The count has stayed the same since 2020, though the underlying diagnosis codes get updated annually to include new clinical conditions. Each HCC gets assigned a risk factor that contributes to a patient’s overall risk score. CMS 2024 HCC Model
How many HCC codes are there in 2021?
In 2021, ICD-10-CM diagnosis codes were mapped to 86 HCC categories under the CMS-HCC Version 24 model
Version 24 used over 71,000 ICD-10-CM codes grouped into 86 HCCs to calculate risk scores. That version included updates to add new diagnoses and retire outdated ones. The structure hasn't changed much in later versions. CMS HCC Version 24 Memo
How is HCC risk score calculated?
An HCC risk score is calculated by summing relative factors for each patient’s demographic variables and diagnosed HCCs
- First, identify all active diagnoses that map to HCCs
- Then apply the relative factor (risk weight) for each HCC and demographic variable
- Sum all those factors to generate a raw risk score
- Finally, normalize the score to reflect expected costs relative to the average beneficiary
Higher scores mean greater expected healthcare use. The model even accounts for interactions between conditions—like diabetes with chronic kidney disease. CMS HCC Scoring Methodology
Is HCC an aggressive cancer?
Hepatocellular carcinoma (HCC) is an aggressive malignancy and the third leading cause of cancer-related death worldwide
It often develops in patients with cirrhosis or chronic hepatitis, which makes early detection tricky. Because it progresses quickly and treatment options are limited in advanced stages, the prognosis is generally poor. High-risk patients should get surveillance with ultrasound and alpha-fetoprotein testing. American Cancer Society
Is HCC a terminal for cancer?
Yes—when HCC reaches end-stage, it is considered terminal, with median survival typically less than 3–4 months
About 15–20% of patients already have end-stage disease at diagnosis. Symptoms can include severe pain, fluid buildup in the abdomen, jaundice, and brain dysfunction from liver failure. Palliative care and hospice become essential for managing symptoms and maintaining quality of life. ACS End-Stage Cancer Care
What are the stages of HCC?
HCC is staged using the Barcelona Clinic Liver Cancer (BCLC) system, which integrates tumor burden, liver function, and performance status
| Stage | Performance Status | Tumor Stage |
|---|
| Stage 0 (Very Early) | 0 | Single tumor ≤2 cm |
| Stage A (Early) | 0 | Single tumor or 3 tumors ≤3 cm |
| Stage B (Intermediate) | 0 | Large, multinodular tumor without vascular invasion |
| Stage C (Advanced) | 1–2 | Vascular invasion or extrahepatic spread |
| Stage D (End-Stage) | 3–4 | Any tumor stage with poor performance status |
Treatment options change dramatically by stage. Early stages might get curative therapies like ablation or resection, while advanced disease often requires systemic therapy or palliation. BCLC Staging System
