AutoICD API

C31.9

Billable

Malignant neoplasm of accessory sinus, unspecified

Malignant neoplasm of accessory sinus, unspecified

Status

Billable / Specific

Block

C30-C39

Parent Code

C31

ICD-11 Mapping

1 equivalent

Coding Notes

Includes

Conditions included under this code

  • malignant neoplasm of middle ear

Excludes 1

Codes that cannot be used together with this code (mutual exclusion)

Related Codes(5)
C31.0

Malignant neoplasm of maxillary sinus

BillableC31.1

Malignant neoplasm of ethmoidal sinus

BillableC31.2

Malignant neoplasm of frontal sinus

BillableC31.3

Malignant neoplasm of sphenoid sinus

BillableC31.8

Malignant neoplasm of overlapping sites of accessory sinuses

Billable
ICD-11 Equivalents(1)

ICD-11 Equivalents

View full mapping

Corresponding ICD-11 codes from the WHO crosswalk mapping

2C22.ZMalignant neoplasms of accessory sinuses, unspecifiedequivalentPrimary
Also Known As / Clinical Terms(81)

SNOMED CT

UMLS

Clinical Terms

  • Malignant tumor of nasal sinus
  • Malignant Accessory Sinus Neoplasm
  • Malignant tumour of nasal sinus
  • Primary squamous cell carcinoma of accessory sinus
  • Primary malignant neoplasm of nasal cavity
  • Malignant Paranasal Sinus Neoplasm
  • Malignant Tumor of Paranasal Sinus
  • Malignant Neoplasm of Paranasal Sinus
  • SNUC - sinonasal undifferentiated carcinoma
  • Malignant Accessory Sinus Tumor
  • Nasal sinus cancer
  • cancer nasal sinus
  • Primary carcinoma of accessory sinus
  • Primary sinonasal undifferentiated carcinoma
  • Primary adenocarcinoma of accessory sinus
  • Adenocarcinoma of accessory sinus
  • Primary malignant neoplasm of accessory sinus
  • Primary undifferentiated carcinoma of nasal sinus
  • Malignant Tumor of the Accessory Sinus
  • Malignant melanoma of accessory sinus
  • Malignant Paranasal Sinus Tumor
  • Malignant Tumor of the Paranasal Sinus
  • Malignant neoplasm of nasal sinus (disorder)
  • Primary squamous cell carcinoma of nasal cavity
  • Malignant neoplasm of nasal sinus
  • Carcinoma of nasal cavity
  • Primary squamous cell carcinoma of nasal cavity and paranasal sinus
  • Squamous cell carcinoma of accessory sinus
  • Squamous cell carcinoma of nose
  • Undifferentiated carcinoma of nasal sinus
  • Malignant Neoplasm of the Accessory Sinus
  • Sinonasal undifferentiated carcinoma
  • Malignant epithelial neoplasm of nasal cavity
  • Malignant Neoplasm of the Paranasal Sinus
  • Melanoma of accessory sinus
  • Malignant Tumor of Accessory Sinus
  • Malignant neoplasm of nasal cavities, middle ear and accessory sinuses
Frequently Asked Questions
What is the ICD-10 code for malignant neoplasm of accessory sinus, unspecified?

The ICD-10-CM code for malignant neoplasm of accessory sinus, unspecified is C31.9. The full clinical description is "Malignant neoplasm of accessory sinus, unspecified". C31.9 is a billable/specific code that can be used on insurance claims and medical billing.

What does ICD-10 code C31.9 mean?

ICD-10-CM code C31.9 represents “Malignant neoplasm of accessory sinus, unspecified”. It is classified under Chapter 2: Neoplasms and is a billable/specific code that can be used on a claim.

Is C31.9 a billable code?

Yes, C31.9 is a billable/specific ICD-10-CM code and can be used to indicate a diagnosis on a medical claim.

What chapter is C31.9 in?

C31.9 is in Chapter 2: Neoplasms (codes C00-D49).

What codes cannot be used with C31.9?

C31.9 has Excludes1 notes indicating codes that cannot be used together with it, including: mesothelioma (C45.-).

What SNOMED CT codes does C31.9 map to?

C31.9 maps to 15 SNOMED CT concepts: 1255092002, 448990005, 707350007, 187828007, 363506007, and 10 more. SNOMED CT is a clinical terminology used in electronic health records.

What are the UMLS CUIs for C31.9?

C31.9 is linked to 1 UMLS Concept Unique Identifier: C0153474. The UMLS (Unified Medical Language System) integrates multiple biomedical vocabularies maintained by the U.S. National Library of Medicine.

How does C31.9 relate to ICF functioning codes?

ICF (International Classification of Functioning, Disability and Health) codes describe how conditions like malignant neoplasm of accessory sinus, unspecified affect a person's functioning: body functions, activities, participation, and environmental factors. AutoICD provides ICF Core Sets for 12+ conditions and can map clinical text to ICF categories automatically. Browse the ICF directory to explore functioning codes.

What is the ICD-11 equivalent of C31.9?

C31.9 maps to the ICD-11 code: 2C22.Z (Malignant neoplasms of accessory sinuses, unspecified).

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Includes SNOMED Clinical Terms® (SNOMED CT®) used by permission of SNOMED International. Includes content from the UMLS Metathesaurus, courtesy of the U.S. National Library of Medicine.