D49.9 — Neoplasm of unspecified behavior of unspecified site

BillableUnspecified

Is D49.9 billable?

Yes, but D49.9 is an unspecified code. D49.9 is a valid, billable ICD-10-CM code for encounters from October 1, 2026 through September 30, 2027. However, D49.9 is an unspecified or catch-all code. Payers apply additional scrutiny to unspecified codes and many deny them when the medical record supports a more specific option, so check the documentation before selecting D49.9 — the more specific alternatives are listed below.

More specific alternatives

D49.9 at a glance

Code	D49.9
Description	Neoplasm of unspecified behavior of unspecified site
Billable	Yes
Code set	ICD-10-CM FY2027
Valid for encounters	October 1, 2026 – September 30, 2027

Which MS-DRGs does D49.9 group to?

D49.9 sits in MDC 17 and helps define the logic of 3 MS-DRGs (version 44, FY2027). Which one a stay actually groups to also depends on procedures and secondary diagnoses.

826Myeloproliferative Disorders or Poorly Differentiated Neoplasms with Major O.R. Procedures with MCCsurgical
827Myeloproliferative Disorders or Poorly Differentiated Neoplasms with Major O.R. Procedures with CCsurgical
828Myeloproliferative Disorders or Poorly Differentiated Neoplasms with Major O.R. Procedures without CC/MCCsurgical

How is D49.9 listed in the Alphabetic Index?

These are the routes through the Alphabetic Index that lead to D49.9. They show the wording a clinician may have documented, which often differs from the Tabular description.

Dermatomyositis › inneoplastic disease (acute) (chronic)
Dermatopolymyositis › in neoplastic disease
Neuromyopathy › paraneoplastic
Neuropathy, neuropathic › paraneoplastic
Arthropathy › in › neoplastic disease NOS
Encephalopathy › in › neoplastic disease (acute)
Myelopathy › in › neoplastic disease (spinal cord)
Polyneuropathy › in › neoplastic disease (peripheral)
Ataxia, ataxy, ataxic › cerebellar › in › neoplastic disease
Atrophy, atrophic › systemic affecting central nervous system › in › neoplastic disease (of)
Compression › nerve › root or plexus NOS › neoplastic disease
Myasthenia › syndrome › in › neoplastic disease

Excludes2 — not included here — inherited from D49

The conditions below are not part of D49.9, but a patient may have both at the same time. When documentation supports it, D49.9 and the excluded code may both be reported.

neoplasms of uncertain behavior (D37-D44, D48)

How long has D49.9 existed?

D49.9 has been in ICD-10-CM since at least FY2016, the earliest fiscal year on record here.

Derived from the official order files for FY2016–FY2026. FY2017 and FY2020 publish no order file, so those years are not covered.