C71

C71 is the ICD-10-CM code for malignant neoplasm of the brain. In the United States, ICD-10-CM is the clinical modification of the World Health Organization’s ICD-10 coding system and is used for diagnosis documentation, billing, and health statistics. The C71 category covers malignant tumors that originate within the brain parenchyma. Subcodes within C71 specify the tumor’s anatomic site within the brain, using decimal extensions to indicate more precise locations.

The code does not encode tumor histology; histologic type is typically captured separately using ICD-O pathology codes. In clinical practice, C71 encompasses a range of primary brain cancers, including glioblastoma, other astrocytomas, oligodendrogliomas, ependymomas, medulloblastomas, and other malignant brain neoplasms. It is distinct from benign brain tumors and from tumors arising from other intracranial structures, as well as from brain metastases, which use different codes.

ICD-10-CM codes, including C71, support patient care, billing, epidemiological tracking, and research. The coding system is maintained and updated annually to reflect advances in medical knowledge and coding guidelines. C71 thus serves as a standardized label for primary malignant brain neoplasms within clinical documentation and administrative processes.