Short answer · Medically reviewed summary · Last updated: 2026-05-08
Glioblastoma multiforme is classified under ICD-10 code C71.1 (malignant neoplasm of the frontal lobe) or other codes within the C71 category depending on the tumor's specific location, while its legacy ICD-9 code is 191.1. As a highly aggressive primary brain tumor, Glioblastoma multiforme requires precise clinical coding to ensure accurate tracking for treatment planning and insurance authorization. What exactly is Glioblastoma multiforme? Glioblastoma multiforme, often abbreviated as GBM, is a grade 4 astrocytoma characterized by rapid cell growth and extensive infiltration into surrounding brain tissue.
ICD10 code of Glioblastoma multiforme and ICD9 code
ICD-10 and ICD-9 codes for Glioblastoma multiforme, with classification details for clinicians, coders and patients.
Glioblastoma multiforme is classified under ICD-10 code C71.1 (malignant neoplasm of the frontal lobe) or other codes within the C71 category depending on the tumor's specific location, while its legacy ICD-9 code is 191.1. As a highly aggressive primary brain tumor, Glioblastoma multiforme requires precise clinical coding to ensure accurate tracking for treatment planning and insurance authorization.
What exactly is Glioblastoma multiforme?
Glioblastoma multiforme, often abbreviated as GBM, is a grade 4 astrocytoma characterized by rapid cell growth and extensive infiltration into surrounding brain tissue. Because Glioblastoma multiforme is the most aggressive form of primary brain cancer in adults, understanding its classification is essential for navigating the complex diagnostic and treatment landscape.
How is the coding for Glioblastoma multiforme determined?
Medical coders use the International Classification of Diseases (ICD) system to standardize reporting. While C71.1 is commonly used for frontal lobe tumors, Glioblastoma multiforme can arise in any part of the brain. Providers must select the code that corresponds precisely to the anatomical site:
- C71.0: Malignant neoplasm of the cerebrum, except lobes and ventricles
- C71.1: Malignant neoplasm of the frontal lobe
- C71.2: Malignant neoplasm of the temporal lobe
- C71.3: Malignant neoplasm of the parietal lobe
- C71.4: Malignant neoplasm of the occipital lobe
Why is accurate documentation vital for patients?
For the 85 members of the DiseaseMaps.org community living with Glioblastoma multiforme, accurate medical coding is more than administrative; it is a gateway to specialized care. Proper coding ensures that clinical trial eligibility, insurance coverage for advanced neuro-oncology therapies, and longitudinal data tracking remain accurate. Glioblastoma multiforme is a complex diagnosis, and clear communication between your neuro-oncologist and your billing department helps reduce the logistical burden during treatment.
Next steps
- Consult your neuro-oncologist to confirm the specific anatomical site of your Glioblastoma multiforme for accurate documentation.
- Join the DiseaseMaps.org community to connect with others who have navigated the diagnostic and treatment paths for Glioblastoma multiforme.
- Request a copy of your pathology report to ensure your diagnosis is correctly recorded in your electronic health record.
Medical disclaimer: This content is for informational purposes only and does not constitute professional medical advice, diagnosis, or treatment; always seek the advice of your physician or other qualified health provider.
References
- NIH National Cancer Institute (NCI) - Adult Central Nervous System Tumors
- World Health Organization (WHO) Classification of Tumors of the Central Nervous System
- ICD-10 Data: Malignant Neoplasm of Brain (C71)
- American Brain Tumor Association (ABTA)
