D35.4
BillableBenign neoplasm of pineal gland
Last updated: FY2026 ICD-10-CM (Oct 1, 2025 – Sep 30, 2026) | CMS-HCC V28 (100% phase-in, PY2026)
Is D35.4 an HCC code?
Yes. D35.4 maps to Melanoma and Other Skin Cancers 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 D35.4
For D35.4 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 D35.4 during that encounter — not just copy-forwarded from a problem list.
What This Code Means
D35.4 is the ICD-10-CM diagnosis code for benign neoplasm of pineal gland. A noncancerous tumor of the pineal gland, a small gland in the center of the brain that produces melatonin. D35.4 sits in the ICD-10-CM chapter for neoplasms (c00-d49), within the section covering benign neoplasms, except benign neuroendocrine tumors (d10-d36).
Under the CMS-HCC V28 risk adjustment model, D35.4 maps to Melanoma and Other Skin Cancers (HCC 23) with a community, non-dual, aged base RAF weight of 0.251. Under the older CMS-HCC V24 model, D35.4 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.
Pineal gland tumors are uncommon; verify benign histology from pathology report. Because D35.4 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 D35.4 sourced directly from the CMS-HCC risk adjustment model files and the CMS ICD-10-CM code set.
Coding Tips
- •Pineal gland tumors are uncommon; verify benign histology from pathology report
- •Document any symptoms related to increased intracranial pressure or hormonal effects
Clinical Significance
Benign neoplasm of the pineal gland encompasses tumors such as pineocytomas (WHO Grade I), which arise from the pinealocytes of this midline brain structure responsible for melatonin production. Pineal region tumors can present with obstructive hydrocephalus, Parinaud syndrome (paralysis of upward gaze), and endocrine disturbances. Despite benign histology, their deep central location makes surgical access challenging.
Documentation Requirements
- ✓MRI brain demonstrating a pineal region mass with characteristic features.
- ✓If biopsied or resected, pathology must confirm benign histology (WHO Grade I pineocytoma or other benign pineal tumor).
- ✓Document the presence of hydrocephalus, visual symptoms, and any endocrine abnormalities.
- ✓Tumor markers (AFP, beta-HCG) should be documented to rule out germ cell tumors.