C34.11
BillableMalignant neoplasm of upper lobe, right bronchus or lung
Last updated: FY2026 ICD-10-CM (Oct 1, 2025 – Sep 30, 2026) | CMS-HCC V28 (100% phase-in, PY2026)
Is C34.11 an HCC code?
Yes. C34.11 maps to Lung and Other Severe Cancers under the CMS-HCC V28 risk adjustment model (and Lung and Other Severe 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 C34.11
For C34.11 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 C34.11 during that encounter — not just copy-forwarded from a problem list.
What This Code Means
C34.11 is the ICD-10-CM diagnosis code for malignant neoplasm of upper lobe, right bronchus or lung. This code represents cancer that has started in the upper portion of the right lung or the bronchus (airway) leading to it. It is a malignant tumor, meaning it is cancerous and can spread to other parts of the body. C34.11 sits in the ICD-10-CM chapter for neoplasms (c00-d49), within the section covering malignant neoplasms of respiratory and intrathoracic organs (c30-c39).
Under the CMS-HCC V28 risk adjustment model, C34.11 maps to Lung and Other Severe Cancers (HCC 20) with a community, non-dual, aged base RAF weight of 0.000. Under the older V24 model, C34.11 mapped to the same category but with a base RAF weight of 0.973 — V28 recalibrated weights across the entire model. 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 laterality (right side) and specific lobe (upper) are documented in the medical record before assigning this code. Because C34.11 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 C34.11 sourced directly from the CMS-HCC risk adjustment model files and the CMS ICD-10-CM code set.
Coding Tips
- •Verify the laterality (right side) and specific lobe (upper) are documented in the medical record before assigning this code
- •This code does not include histology type or stage; additional codes may be needed to specify the type of lung cancer (e.g., adenocarcinoma, squamous cell) and TNM staging when available
Clinical Significance
Right upper lobe lung cancer is the most common presentation of lung cancer overall. The right upper lobe is the most frequent site, particularly for adenocarcinoma. Superior sulcus (Pancoast) tumors at the apex carry unique clinical features including Horner syndrome and brachial plexus involvement. Accurate coding supports treatment planning and risk adjustment.
Documentation Requirements
- ✓Pathology with histological type (adenocarcinoma, squamous cell, large cell, small cell)
- ✓Molecular markers (EGFR, ALK, ROS1, PD-L1, KRAS) for non-small cell lung cancer
- ✓Imaging confirming right upper lobe location with laterality
- ✓TNM staging with nodal and metastatic assessment
- ✓Assessment for Pancoast features if apical location