2024 ICD-10-CM Diagnosis Code D42.9

Neoplasm of uncertain behavior of meninges, unspecified

ICD-10-CM Code:
ICD-10 Code for:
Neoplasm of uncertain behavior of meninges, unspecified
Is Billable?
Yes - Valid for Submission
Chronic Condition Indicator: [1]
Code Navigator:

Code Classification

  • Neoplasms
    • Neoplasms of uncertain behavior, polycythemia vera and myelodysplastic syndromes
      • Neoplasm of uncertain behavior of meninges

D42.9 is a billable diagnosis code used to specify a medical diagnosis of neoplasm of uncertain behavior of meninges, unspecified. The code is valid during the current fiscal year for the submission of HIPAA-covered transactions from October 01, 2023 through September 30, 2024.

The following anatomical sites found in the Table of Neoplasms reference this diagnosis code given the correct histological behavior: Neoplasm, neoplastic arachnoid or Neoplasm, neoplastic dura (cranial) (mater) or Neoplasm, neoplastic meninges or Neoplasm, neoplastic pia mater or Neoplasm, neoplastic subdural .

Unspecified diagnosis codes like D42.9 are acceptable when clinical information is unknown or not available about a particular condition. Although a more specific code is preferable, unspecified codes should be used when such codes most accurately reflect what is known about a patient's condition. Specific diagnosis codes should not be used if not supported by the patient's medical record.

Approximate Synonyms

The following clinical terms are approximate synonyms or lay terms that might be used to identify the correct diagnosis code:

  • Meningioma of uncertain behavior
  • Neoplasm of uncertain behavior of meninges
  • Solitary fibrous tumor
  • Solitary fibrous tumor of meninges

Clinical Classification

Clinical Information

  • Arachnoid

    a delicate membrane enveloping the brain and spinal cord. it lies between the pia mater and the dura mater. it is separated from the pia mater by the subarachnoid cavity which is filled with cerebrospinal fluid.
  • Arachnoid Cysts

    intracranial or spinal cavities containing a cerebrospinal-like fluid, the wall of which is composed of arachnoidal cells. they are most often developmental or related to trauma. intracranial arachnoid cysts usually occur adjacent to arachnoidal cistern and may present with hydrocephalus; headache; seizures; and focal neurologic signs. (from joynt, clinical neurology, 1994, ch44, pp105-115)
  • Arachnoiditis

    acute or chronic inflammation of the arachnoid membrane of the meninges most often involving the spinal cord or base of the brain. this term generally refers to a persistent inflammatory process characterized by thickening of the arachnoid membrane and dural adhesions. associated conditions include prior surgery, infections, trauma, subarachnoid hemorrhage, and chemical irritation. clinical features vary with the site of inflammation, but include cranial neuropathies, radiculopathies, and myelopathies. (from joynt, clinical neurology, 1997, ch48, p25)
  • Medulloblastoma

    a malignant neoplasm that may be classified either as a glioma or as a primitive neuroectodermal tumor of childhood (see neuroectodermal tumor, primitive). the tumor occurs most frequently in the first decade of life with the most typical location being the cerebellar vermis. histologic features include a high degree of cellularity, frequent mitotic figures, and a tendency for the cells to organize into sheets or form rosettes. medulloblastoma have a high propensity to spread throughout the craniospinal intradural axis. (from devita et al., cancer: principles and practice of oncology, 5th ed, pp2060-1)
  • Meninges

    the three membranes that cover the brain and the spinal cord. they are the dura mater, the arachnoid, and the pia mater.
  • Meningocele

    a congenital or acquired protrusion of the meninges, unaccompanied by neural tissue, through a bony defect in the skull or vertebral column.
  • Pia Mater

    the innermost layer of the three meninges covering the brain and spinal cord. it is the fine vascular membrane that lies under the arachnoid and the dura mater.

Convert D42.9 to ICD-9-CM

  • ICD-9-CM Code: 237.6 - Unc behav neo meninges
    Approximate Flag - The approximate mapping means there is not an exact match between the ICD-10 and ICD-9 codes and the mapped code is not a precise representation of the original code.

Table of Neoplasms

This code is referenced in the table of neoplasms by anatomical site. For each site there are six possible code numbers according to whether the neoplasm in question is malignant, benign, in situ, of uncertain behavior, or of unspecified nature. The description of the neoplasm will often indicate which of the six columns is appropriate.

Where such descriptors are not present, the remainder of the Index should be consulted where guidance is given to the appropriate column for each morphological (histological) variety listed. However, the guidance in the Index can be overridden if one of the descriptors mentioned above is present.

Neoplasm, neoplastic Malignant
CaInSitu Benign Uncertain
»Neoplasm, neoplastic
C70.9C79.49 D32.9D42.9D49.7
»Neoplasm, neoplastic
  »dura (cranial) (mater)
C70.9C79.49 D32.9D42.9D49.7
»Neoplasm, neoplastic
C70.9C79.49 D32.9D42.9D49.7
»Neoplasm, neoplastic
  »pia mater
C70.9C79.40 D32.9D42.9D49.7
»Neoplasm, neoplastic
C70.9C79.32 D32.9D42.9D49.7

Patient Education

Spinal Cord Diseases

Your spinal cord is a bundle of nerves that runs down the middle of your back. It carries signals back and forth between your body and your brain. It is protected by your vertebrae, which are the bone disks that make up your spine. If you have an accident that damages the vertebrae or other parts of the spine, this can also injure the spinal cord. Other spinal cord problems include:

  • Tumors
  • Infections such as meningitis and polio
  • Inflammatory diseases
  • Autoimmune diseases
  • Degenerative diseases such as amyotrophic lateral sclerosis and spinal muscular atrophy

Symptoms vary but might include pain, numbness, loss of sensation and muscle weakness. These symptoms can occur around the spinal cord, and also in other areas such as your arms and legs. Treatments often include medicines and surgery.

[Learn More in MedlinePlus]

Code History

  • FY 2024 - No Change, effective from 10/1/2023 through 9/30/2024
  • FY 2023 - No Change, effective from 10/1/2022 through 9/30/2023
  • FY 2022 - No Change, effective from 10/1/2021 through 9/30/2022
  • FY 2021 - No Change, effective from 10/1/2020 through 9/30/2021
  • FY 2020 - No Change, effective from 10/1/2019 through 9/30/2020
  • FY 2019 - No Change, effective from 10/1/2018 through 9/30/2019
  • FY 2018 - No Change, effective from 10/1/2017 through 9/30/2018
  • FY 2017 - No Change, effective from 10/1/2016 through 9/30/2017
  • FY 2016 - New Code, effective from 10/1/2015 through 9/30/2016. This was the first year ICD-10-CM was implemented into the HIPAA code set.


[1] Chronic - a chronic condition code indicates a condition lasting 12 months or longer and its effect on the patient based on one or both of the following criteria:

  • The condition results in the need for ongoing intervention with medical products,treatment, services, and special equipment
  • The condition places limitations on self-care, independent living, and social interactions.