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D49

Non-Billable (Header)

Neoplasms of unspecified behavior

Last updated: FY2026 ICD-10-CM (Oct 1, 2025 – Sep 30, 2026) | CMS-HCC V28 (100% phase-in, PY2026)

What This Code Means

D49 is the ICD-10-CM diagnosis code for neoplasms of unspecified behavior. D49 sits in the ICD-10-CM chapter for neoplasms (c00-d49), within the section covering neoplasms of unspecified behavior (d49).

Header codes like D49 cannot be reported on claims directly — they organize child codes that share clinical context but the actual diagnosis must be coded to the highest level of specificity supported by the documentation. Coders should look at D49's child codes and select the one that matches the patient's documented presentation, since payers reject header codes submitted as the primary diagnosis. For risk adjustment workflows, header codes never contribute to a Medicare Advantage member's RAF score on their own; only billable child codes that happen to map to a payment HCC affect risk-adjusted plan payments.

HCC Buddy maintains structured V28 and V24 mapping, RAF weights, and MEAT documentation criteria for D49 sourced directly from the CMS-HCC risk adjustment model files and the CMS ICD-10-CM code set.

Includes

  • 'growth' NOS
  • neoplasm NOS
  • new growth NOS
  • tumor NOS

Excludes 1 — Do NOT code together

  • neoplasms of uncertain behavior (D37-D44, D48)

Child Codes

Code Hierarchy

D49Neoplasms of unspecified behavior
D49Neoplasms of unspecified behavior

More on D49

Referenced in blog posts

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