C08.0
BillableMalignant neoplasm of submandibular gland
Last updated: FY2026 ICD-10-CM (Oct 1, 2025 – Sep 30, 2026) | CMS-HCC V28 (100% phase-in, PY2026)
Is C08.0 an HCC code?
Yes. C08.0 maps to Breast, Prostate, Colorectal and Other Cancers and Tumors under the CMS-HCC V28 risk adjustment model (and Colorectal, Bladder, 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 C08.0
For C08.0to 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 C08.0 during that encounter — not just copy-forwarded from a problem list.
What This Code Means
C08.0 is the ICD-10-CM diagnosis code for malignant neoplasm of submandibular gland. Cancer that develops in the submandibular gland, a salivary gland located under the jaw. C08.0 sits in the ICD-10-CM chapter for neoplasms (c00-d49), within the section covering malignant neoplasms of lip, oral cavity and pharynx (c00-c14).
Under the CMS-HCC V28 risk adjustment model, C08.0 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, C08.0 maps to Colorectal, Bladder, and Other Cancers (HCC 11) with a community, non-dual, aged base RAF weight of 0.306. 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 laterality documentation (left or right submandibular gland). Because C08.0 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 C08.0 sourced directly from the CMS-HCC risk adjustment model files and the CMS ICD-10-CM code set.
Coding Tips
Clinical Significance
Malignant neoplasm of the submandibular gland is the second most common major salivary gland cancer. The submandibular gland has a higher proportion of malignant tumors relative to benign ones compared to the parotid, meaning a submandibular mass has a greater likelihood of being malignant and warrants prompt evaluation.
Documentation Requirements
- ✓Pathology-confirmed malignancy with histological subtype
- ✓Specific documentation of submandibular gland as primary site
- ✓Laterality (right or left)
- ✓TNM staging including assessment of lingual nerve and marginal mandibular nerve involvement
- ✓Imaging evaluation for bone invasion of mandible and regional lymphadenopathy
Commonly Confused Codes
- •C07 — Malignant neoplasm of parotid gland; the parotid is anterior/inferior to the ear, the submandibular is beneath the mandible
- •C08.1 — Malignant neoplasm of sublingual gland; the sublingual gland is under the tongue, the submandibular is under the jawbone
- •C08.9 — Major salivary gland, unspecified; avoid when submandibular gland is clearly documented
- •D11.7 — Benign neoplasm of other major salivary glands; distinguish benign from malignant submandibular tumors