2026 ICD-10-CM Diagnosis Code D37.05Neoplasm of uncertain behavior of pharynx

ICD-10-CM CodesC00–D49D37-D48D37

ICD-10-CM D37.05
CMSSource: CMS FY 2026 ICD-10-CM dataset · Effective Oct 1, 2025 – Sep 30, 2026

D37.05 is a billable ICD-10-CM diagnosis code for neoplasm of uncertain behavior of pharynx. It is valid on HIPAA claims for fiscal year 2026 (October 1, 2025 through September 30, 2026) and groups to MS-DRG 146 through 148. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Neoplasms of unspecified nature or uncertain behavior.

Code Identity

ICD-10-CM Code
D37.05
Billable Status
Yes — Valid for Submission
Code Describes
Neoplasm of uncertain behavior of pharynx
Short Description
Neoplasm of uncertain behavior of pharynx
Same as the full description in the CMS dataset.
Parent Code
Neoplasm of uncertain behavior of lip, oral cavity and pharynx

Code Classification

ChapterC00–D49Neoplasms
SectionD37-D48Neoplasms of uncertain behavior, polycythemia vera and myelodysplastic syndromes
CategoryD37Neoplasm of uncertain behavior of oral cavity and digestive organs
This CodeD37.05Neoplasm of uncertain behavior of pharynx

Approximate SynonymsGuidance

Alternate terms and clinical phrases that map to this code.

  • Congenital nasopharyngeal teratoma
  • Mass of vallecula of epiglottis
  • Neoplasm of adenoid
  • Neoplasm of anterior aspect of epiglottis
  • Neoplasm of anterior wall of nasopharynx
  • Neoplasm of hypopharyngeal aspect of aryepiglottic fold
  • Neoplasm of hypopharyngeal aspect of interarytenoid fold
  • Neoplasm of lateral wall of nasopharynx
  • Neoplasm of postcricoid region
  • Neoplasm of posterior hypopharyngeal wall
  • Neoplasm of posterior wall of oropharynx
  • Neoplasm of pyriform sinus
  • Neoplasm of superior wall of nasopharynx
  • Neoplasm of tonsillar fossa
  • Neoplasm of uncertain behavior of adenoid
  • Neoplasm of uncertain behavior of anterior aspect of epiglottis
  • Neoplasm of uncertain behavior of anterior wall of nasopharynx
  • Neoplasm of uncertain behavior of aryepiglottic fold
  • Neoplasm of uncertain behavior of epiglottis
  • Neoplasm of uncertain behavior of hypopharyngeal aspect of aryepiglottic fold
  • Neoplasm of uncertain behavior of hypopharyngeal aspect of interarytenoid fold
  • Neoplasm of uncertain behavior of hypopharynx
  • Neoplasm of uncertain behavior of junctional region of epiglottis
  • Neoplasm of uncertain behavior of lateral wall of nasopharynx
  • Neoplasm of uncertain behavior of lateral wall of oropharynx
  • Neoplasm of uncertain behavior of lip, oral cavity and pharynx
  • Neoplasm of uncertain behavior of nasopharynx
  • Neoplasm of uncertain behavior of oropharynx
  • Neoplasm of uncertain behavior of pharynx
  • Neoplasm of uncertain behavior of postcricoid region
  • Neoplasm of uncertain behavior of posterior hypopharyngeal wall
  • Neoplasm of uncertain behavior of posterior wall of nasopharynx
  • Neoplasm of uncertain behavior of posterior wall of oropharynx
  • Neoplasm of uncertain behavior of pyriform sinus
  • Neoplasm of uncertain behavior of soft tissues of neck
  • Neoplasm of uncertain behavior of superior wall of nasopharynx
  • Neoplasm of uncertain behavior of tonsil
  • Neoplasm of uncertain behavior of tonsillar fossa
  • Neoplasm of uncertain behavior of tonsillar pillar
  • Neoplasm of uncertain behavior of vallecula of epiglottis
  • Neoplasm of uncertain behavior of Waldeyer's ring
  • Neoplasm of vallecula

Tabular List NotesGuidance

Coding notes and annotation back-references applicable to this code.

Inclusion Terms

  • Neoplasm of uncertain behavior of aryepiglottic fold of pharynx NOS
  • Neoplasm of uncertain behavior of hypopharyngeal aspect of aryepiglottic fold of pharynx
  • Neoplasm of uncertain behavior of marginal zone of aryepiglottic fold of pharynx

Clinical ClassificationClinical

AHRQ’s CCSR groups this code into broader clinical categories.

CCSR NEO072
Neoplasms of unspecified nature or uncertain behavior
Default principal diagnosis: inpatient Yes · outpatient Yes

Clinical InformationClinical

  • Oropharyngeal Neoplasms

    tumors or cancer of the oropharynx.
  • Oropharynx

    the middle portion of the pharynx that lies posterior to the mouth, inferior to the soft palate, and superior to the base of the tongue and epiglottis. it has a digestive function as food passes from the mouth into the oropharynx before entering esophagus.

Table of NeoplasmsClinical

Anatomical sites in the Table of Neoplasms that reference this code family.

SiteMalig.
Primary
Malig.
Secondary
Ca
in situ
BenignUncertainUnspec.
adenoid (pharynx) (tissue)C11.1C79.89D00.08D10.6D37.05D49.0
aryepiglottic foldC13.1C79.89D00.08D10.7D37.05D49.0
aryepiglottic fold hypopharyngeal aspectC13.1C79.89D00.08D10.7D37.05D49.0
aryepiglottic fold marginal zoneC13.1C79.89D00.08D10.7D37.05D49.0
auditory tube openingC11.2C79.89D00.08D10.6D37.05D49.0
branchial (cleft) (cyst) (vestiges)C10.4C79.89D00.08D10.5D37.05D49.0
cartilage (articular) (joint) NEC [See Also: Neoplasm, bone] epiglottis anterior surfaceC10.1C79.89D00.08D10.5D37.05D49.0
choanaC11.3C79.89D00.08D10.6D37.05D49.0
cricoidC13.0C79.89D00.08D10.7D37.05D49.0
cricopharynxC13.0C79.89D00.08D10.7D37.05D49.0
epiglottis anterior aspect or surfaceC10.1C79.89D00.08D10.5D37.05D49.0
epiglottis free border (margin)C10.1C79.89D00.08D10.5D37.05D49.0
epiglottis junctional regionC10.8C79.89D00.08D10.5D37.05D49.0
fauces, faucial NECC10.9C79.89D00.08D10.5D37.05D49.0
fauces, faucial NEC pillarsC09.1C79.89D00.08D10.5D37.05D49.0
fauces, faucial NEC tonsilC09.9C79.89D00.08D10.4D37.05D49.0
fornixC11.3C79.89D00.08D10.6D37.05D49.0
fornix pharyngealC11.3C79.89D00.08D10.6D37.05D49.0
fossa (of) piriformC12C79.89D00.08D10.7D37.05D49.0
fossa (of) pyriformC12C79.89D00.08D10.7D37.05D49.0
fossa (of) RosenmullerC11.2C79.89D00.08D10.6D37.05D49.0
fossa (of) tonsillarC09.0C79.89D00.08D10.5D37.05D49.0
glosso-epiglottic fold (s)C10.1C79.89D00.08D10.5D37.05D49.0
glossopalatine foldC09.1C79.89D00.08D10.5D37.05D49.0
glossopharyngeal sulcusC09.0C79.89D00.08D10.5D37.05D49.0
hypopharynx, hypopharyngeal NECC13.9C79.89D00.08D10.7D37.05D49.0
hypopharynx, hypopharyngeal NEC postcricoid regionC13.0C79.89D00.08D10.7D37.05D49.0
hypopharynx, hypopharyngeal NEC posterior wallC13.2C79.89D00.08D10.7D37.05D49.0
hypopharynx, hypopharyngeal NEC pyriform fossa (sinus)C12C79.89D00.08D10.7D37.05D49.0
interarytenoid foldC13.1C79.89D00.08D10.7D37.05D49.0
interarytenoid fold hypopharyngeal aspectC13.1C79.89D00.08D10.7D37.05D49.0
interarytenoid fold marginal zoneC13.1C79.89D00.08D10.7D37.05D49.0
laryngopharynxC13.9C79.89D00.08D10.7D37.05D49.0
larynx, laryngeal NEC extrinsic NEC meaning hypopharynxC13.9C79.89D00.08D10.7D37.05D49.0
nasopharynx, nasopharyngealC11.9C79.89D00.08D10.6D37.05D49.0
nasopharynx, nasopharyngeal floorC11.3C79.89D00.08D10.6D37.05D49.0
nasopharynx, nasopharyngeal roofC11.0C79.89D00.08D10.6D37.05D49.0
nasopharynx, nasopharyngeal wallC11.9C79.89D00.08D10.6D37.05D49.0
nasopharynx, nasopharyngeal wall anteriorC11.3C79.89D00.08D10.6D37.05D49.0
nasopharynx, nasopharyngeal wall lateralC11.2C79.89D00.08D10.6D37.05D49.0
nasopharynx, nasopharyngeal wall posteriorC11.1C79.89D00.08D10.6D37.05D49.0
nasopharynx, nasopharyngeal wall superiorC11.0C79.89D00.08D10.6D37.05D49.0
nose, nasal choanaC11.3C79.89D00.08D10.6D37.05D49.0
nose, nasal septum posterior marginC11.3C79.89D00.08D10.6D37.05D49.0
oropharynxC10.9C79.89D00.08D10.5D37.05D49.0
oropharynx branchial cleft (vestige)C10.4C79.89D00.08D10.5D37.05D49.0
oropharynx junctional regionC10.8C79.89D00.08D10.5D37.05D49.0
oropharynx lateral wallC10.2C79.89D00.08D10.5D37.05D49.0
oropharynx pillars or faucesC09.1C79.89D00.08D10.5D37.05D49.0
oropharynx posterior wallC10.3C79.89D00.08D10.5D37.05D49.0
oropharynx valleculaC10.0C79.89D00.08D10.5D37.05D49.0
palate soft nasopharyngeal surfaceC11.3C79.89D00.08D10.6D37.05D49.0
palate soft posterior surfaceC11.3C79.89D00.08D10.6D37.05D49.0
palate soft superior surfaceC11.3C79.89D00.08D10.6D37.05D49.0
pharynx, pharyngealC14.0C79.89D00.08D10.9D37.05D49.0
pharynx, pharyngeal bursaC11.1C79.89D00.08D10.6D37.05D49.0
pharynx, pharyngeal fornixC11.3C79.89D00.08D10.6D37.05D49.0
pharynx, pharyngeal recessC11.2C79.89D00.08D10.6D37.05D49.0
pharynx, pharyngeal regionC14.0C79.89D00.08D10.9D37.05D49.0
pharynx, pharyngeal tonsilC11.1C79.89D00.08D10.6D37.05D49.0
pharynx, pharyngeal wall (lateral) (posterior)C14.0C79.89D00.08D10.9D37.05D49.0
pillars of faucesC09.1C79.89D00.08D10.5D37.05D49.0
piriform fossa or sinusC12C79.89D00.08D10.7D37.05D49.0
postcricoid (region)C13.0C79.89D00.08D10.7D37.05D49.0
postnasal spaceC11.9C79.89D00.08D10.6D37.05D49.0
pyriform fossa or sinusC12C79.89D00.08D10.7D37.05D49.0
retropharyngealC14.0C79.89D00.08D10.9D37.05D49.0
Rosenmuller's fossaC11.2C79.89D00.08D10.6D37.05D49.0
septum nasal posterior marginC11.3C79.89D00.08D10.6D37.05D49.0
sinus (accessory) pyriformC12C79.89D00.08D10.7D37.05D49.0
throatC14.0C79.89D00.08D10.9D37.05D49.0
tonsilC09.9C79.89D00.08D10.4D37.05D49.0
tonsil fauces, faucialC09.9C79.89D00.08D10.4D37.05D49.0
tonsil palatineC09.9C79.89D00.08D10.4D37.05D49.0
tonsil pharyngealC11.1C79.89D00.08D10.6D37.05D49.0
tonsil pillar (anterior) (posterior)C09.1C79.89D00.08D10.5D37.05D49.0
tonsillar fossaC09.0C79.89D00.08D10.5D37.05D49.0
vallecula (epigiottis)C10.0C79.89D00.08D10.5D37.05D49.0
Waldeyer's ringC14.2C79.89D00.08D10.9D37.05D49.0

Patient EducationClinical

Throat Disorders

Your throat is a tube that carries food to your esophagus and air to your windpipe and larynx. The technical name for your throat is the pharynx.

Read the full article at MedlinePlus

Courtesy of MedlinePlus, a service of the U.S. National Library of Medicine.

Convert D37.05 to ICD-9-CMHistory

The closest ICD-9-CM equivalents under the General Equivalence Mappings.

ICD-9-CM
235.1 Unc behav neo oral/phar
Approximate The match is approximate rather than exact.

Code HistoryHistory

FY 2016AddedAdded to the ICD-10-CM code setEffective October 1, 2015, the first year of ICD-10-CM.
FY 2017–2025No changes
FY 2026CurrentCurrent code set, no changesEffective October 1, 2025 through September 30, 2026.

Questions About D37.05Overview

Is D37.05 a billable code?

Yes. This is a billable ICD-10-CM code, specific enough to report neoplasm of uncertain behavior of pharynx on HIPAA-covered claims from October 1, 2025 through September 30, 2026.

What MS-DRG does D37.05 group to?

When neoplasm of uncertain behavior of pharynx is the principal diagnosis on an inpatient stay, it groups to MS-DRG 146, 147, 148, with relative weights from 0.7971 to 2.1174 depending on complications. Higher weights mean higher Medicare reimbursement.

What is the ICD-9 equivalent of D37.05?

Under the General Equivalence Mappings, neoplasm of uncertain behavior of pharynx converts to ICD-9-CM 235.1 (unc behav neo oral/phar). The mapping is approximate, so confirm the match fits the documentation.

Footnotes

[1] Not chronic - A diagnosis code that does not fit the criteria for chronic condition (duration, ongoing medical treatment, and limitations) is considered not chronic. Some codes designated as not chronic are acute conditions. Other diagnosis codes that indicate a possible chronic condition, but for which the duration of the illness is not specified in the code description (i.e., we do not know the condition has lasted 12 months or longer) also are considered not chronic.