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  2. ICD-10-CM Codes List
  3. C00–D49
  4. C69-C72
  5. Malignant neoplasm of meninges (C70)

Malignant neoplasm of meninges (C70)

The ICD-10 code C70 and its extensions are used to classify malignant tumors originating in the meninges, which are the protective layers surrounding the brain and spinal cord. These codes specify whether the cancer affects cerebral, spinal, or unspecified meninges.

Specifically, C70.0 denotes a malignant neoplasm of the cerebral meninges, including tumors known as primary malignant meningiomas or malignant meningiomas of the optic nerve sheath. This category covers cancers arising from the dura mater, arachnoid mater, or pia mater of the brain's meninges. The C70.1 code is used when the malignant neoplasm affects the spinal meninges, involving the dura, arachnoid, or pia mater layers of the spinal cord's protective tissues. For cases where the exact meninges location is not specified, C70.9 captures malignant neoplasms of meninges without further detail and includes terms like malignant melanoma of the meninges or metastatic malignant neoplasm of meninges. These codes help coders and clinicians accurately identify and document primary malignant meningeal tumors for treatment and billing purposes, guiding diagnosis and management of aggressive nervous system cancers.

Clinical Terms

The following clinical terms provide additional context, helping users better understand the clinical background and common associations for each diagnosis listed in this section. Including related terms alongside ICD-10-CM codes supports coders, billers, and healthcare professionals in improving accuracy, enhancing documentation, and facilitating research or patient education.

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.