Listing 13.13 Central Nervous System Cancer in 2026

Primary malignant brain and central nervous system tumors are diagnosed in about 25,400 adults in the United States each year, with 18,760 deaths. Adding pediatric CNS tumors and secondary brain metastases (from lung, breast, melanoma, colorectal, kidney) brings the total burden much higher. Glioblastoma (GBM) alone accounts for about 12,000 US cases per year with a median survival of 15-18 months even with modern therapy.

SSA Listing 13.13 covers malignant CNS tumors. High-grade gliomas, medulloblastoma, primary CNS lymphoma, and any malignant CNS tumor with progression qualify. The 2021 WHO CNS5 classification substantially changed how these tumors are named and graded, and SSA has adapted its evaluation accordingly. Even patients who achieve initial treatment response typically have significant neurologic residuals that persist for years and support ongoing disability at CDR.

The listing text

Paragraph A: Grade III or IV astrocytoma, glioblastoma multiforme

WHO Grade III (anaplastic astrocytoma) or Grade IV (glioblastoma, gliosarcoma) qualifies automatically upon diagnosis. Under 2021 WHO CNS5:

• Glioblastoma, IDH-wildtype, WHO Grade 4 (formerly glioblastoma multiforme)
• Astrocytoma, IDH-mutant, WHO Grade 4 (formerly some GBM IDH-mutant cases, now separated)
• Astrocytoma, IDH-mutant, WHO Grade 3 (formerly anaplastic astrocytoma)
• Oligodendroglioma, IDH-mutant and 1p/19q-codeleted, WHO Grade 3

All Grade 3 and 4 gliomas meet Listing 13.13A regardless of molecular subtype.

Paragraph B: Medulloblastoma or other primary malignant tumors with progression

Primary CNS malignancies not covered by Paragraph A that show progression after prior therapy. Includes:

• Medulloblastoma (posterior fossa embryonal tumor, historically pediatric but adult cases exist)
• Ependymoma, WHO Grade 3
• Primary CNS lymphoma
• Meningeal hemangiopericytoma / solitary fibrous tumor CNS Grade 3
• Chordoma with progression
• Choroid plexus carcinoma
• Pineoblastoma
• Atypical teratoid/rhabdoid tumor (AT/RT)

Paragraph C: Meningeal carcinomatosis / leptomeningeal disease

Metastatic cancer with spread to meninges or spinal cord. Diagnosed by cytology from CSF, meningeal biopsy, or imaging (leptomeningeal enhancement on MRI). This is a devastating late-stage complication of solid tumors and lymphoma with median survival typically under 3 months.

Diagnostic evidence required

SSA requires objective medical evidence:

• Neuroimaging: MRI brain with contrast including DWI, MR spectroscopy, perfusion imaging. Spinal MRI if leptomeningeal disease suspected.
• Pathology report from stereotactic biopsy, open resection, or debulking with:
  • WHO grade (1-4)
  • Histologic type per 2021 WHO CNS5
  • IDH1/IDH2 mutation status
  • ATRX loss
  • 1p/19q codeletion (for oligodendroglioma)
  • MGMT promoter methylation status
  • H3 K27M mutation (diffuse midline glioma)
  • H3 G34 mutation (diffuse hemispheric glioma)
  • TERT promoter mutation
  • EGFR amplification
  • CDKN2A/B homozygous deletion
• Neurologic examination documenting motor, sensory, cognitive, and cranial nerve deficits
• Karnofsky Performance Status (KPS) or ECOG score
• Cognitive testing if applicable (mini-mental status exam at minimum, neuropsychological battery ideal)
• Seizure history with EEG if seizures are a presenting or persistent feature (30-50% of glioma patients)
• CSF cytology and flow cytometry if paragraph C (leptomeningeal) suspected

The Compassionate Allowance overlay

Multiple CNS malignancies on the CAL list:

• Glioblastoma multiforme (all cases)
• Diffuse intrinsic pontine glioma (DIPG)
• Ependymoblastoma (child)
• Malignant brain stem gliomas (child)
• Medulloblastoma with metastases
• Primary CNS lymphoma
• Anaplastic adrenal cancer with distant metastases (extends to nervous system involvement)

CAL processing targets 14-30 days for initial decision. GBM patients typically approve within 2 weeks.

The 2021 WHO CNS5 classification shift

The 2021 update fundamentally reorganized CNS tumor classification around molecular markers rather than histology alone. Key changes affecting SSDI documentation:

• IDH-wildtype glioblastoma is now the only tumor called "glioblastoma" - IDH-mutant Grade 4 gliomas are now called "astrocytoma, IDH-mutant, WHO Grade 4"
• 1p/19q codeletion is required for oligodendroglioma diagnosis (previously histologic)
• H3 K27M mutant tumors are classified as "diffuse midline glioma, H3 K27-altered, WHO Grade 4" regardless of appearance
• H3 G34 mutant hemispheric tumors are separately classified
• Various new pediatric-type gliomas defined molecularly

These changes matter for pathology reports and for how oncologists estimate prognosis. All still meet Listing 13.13A if Grade 3 or 4.

Modern treatment residuals for the CDR

The 3-year remission rule under 13.00H1 applies. For GBM, few patients reach 3-year survival (about 10-15% of GBM patients). For IDH-mutant Grade 3-4 astrocytomas and oligodendrogliomas, 5-year survival is higher (50-80%), and many will reach CDR. Neurologic residuals from tumor and treatment universally support continued disability.

Stupp protocol - surgery + radiation + concurrent/adjuvant temozolomide

Standard for GBM since 2005. Maximal safe resection, then 60 Gy radiation over 6 weeks with concurrent daily temozolomide, then 6-12 cycles adjuvant temozolomide. Residuals:

• Post-surgical neurologic deficits (motor, sensory, language, cognitive, visual field)
• Radiation necrosis (5-20%, can be delayed years)
• Radiation-induced cognitive decline (universal, dose- and volume-dependent)
• Temozolomide-induced myelosuppression (lymphopenia particularly, with increased infection risk)
• MDS/AML risk from alkylating therapy (rare but present)
• Pituitary insufficiency after skull base radiation
• Chronic fatigue lasting years
• Post-treatment seizures (30-50% of glioma patients have seizures at some point)

Tumor treating fields (Optune)

FDA-approved 2011 for GBM. Wearable device delivers alternating electric fields (200 kHz) to disrupt tumor mitosis via transducer arrays on shaved scalp. Requires 18+ hours daily use. EF-14 trial showed 4.9 month median OS improvement in newly diagnosed GBM. Residuals: skin irritation under arrays (universal), lifestyle burden of continuous wear.

Bevacizumab

Anti-VEGF antibody for recurrent GBM. Reduces peritumoral edema and radiographic tumor size but no clear OS benefit at recurrence. Toxicities include hypertension, proteinuria, bleeding, wound healing problems, GI perforation (rare), thromboembolism.

Lomustine (CCNU)

Alkylating agent for recurrent GBM, second-line temozolomide-refractory disease. Delayed myelosuppression (nadir 4-6 weeks post-dose), pulmonary fibrosis with cumulative dose, MDS/AML risk.

Primary CNS lymphoma - high-dose methotrexate + rituximab

Standard induction is high-dose methotrexate (3-8 g/m2) with rituximab, then consolidation with autologous stem cell transplant or whole-brain radiation. Residuals: methotrexate leukoencephalopathy (especially with radiation), cognitive decline, renal dysfunction from methotrexate.

Craniotomy and tumor resection residuals

Depending on tumor location and extent of resection:

• Motor deficits (hemiparesis, monoparesis)
• Aphasia (Broca, Wernicke, or global)
• Visual field cuts (homonymous hemianopia)
• Cranial nerve deficits
• Cognitive impairment (executive function, memory, attention, processing speed)
• Personality/behavioral changes (particularly frontal lobe tumors)
• Seizure disorder
• Cerebellar tumors: ataxia, dysmetria, dysarthria
• Brainstem tumors: cranial nerve palsies, hemiparesis, gaze palsies
• Pituitary/sellar tumors: panhypopituitarism

These neurologic residuals frequently meet or equal listings 11.00 (neurological) and 12.00 (mental disorders) at CDR even if the underlying malignancy is stable.

Worked case examples

Case 1: David, 62, Illinois, IDH-wildtype glioblastoma

David presented with progressive right hand weakness and word-finding difficulty for 6 weeks in January 2026. MRI brain: 4 cm ring-enhancing left frontal lobe mass with peritumoral edema and midline shift. Craniotomy with subtotal resection. Pathology: glioblastoma, IDH-wildtype, WHO Grade 4, MGMT methylated, TERT promoter mutated.

SSDI application filed February 2026. CAL for GBM triggered. Approved 8 days at Illinois DDS. Underwent Stupp protocol (60 Gy radiation + concurrent temozolomide, then adjuvant temozolomide). Added Optune tumor treating fields. Persistent right hemiparesis 4/5, mild expressive aphasia, and post-op focal seizures well-controlled on levetiracetam. Progressed at 16 months, died at 20 months.

Case 2: Rachel, 41, Ohio, IDH-mutant astrocytoma WHO Grade 3

Rachel had a focal seizure while driving in March 2026. MRI: 3.5 cm non-enhancing left temporal mass. Awake craniotomy with gross total resection. Pathology: astrocytoma, IDH1-mutant (R132H), ATRX loss, WHO Grade 3. No 1p/19q codeletion.

SSDI application filed April 2026. Listing 13.13A met (Grade 3 astrocytoma). Approved 4 weeks at Ohio DDS. Adjuvant radiation + PCV (procarbazine + lomustine + vincristine) per CATNON-adapted regimen. IDH-mutant Grade 3 astrocytoma has median OS 10-15 years, so Rachel likely reaches 3-year CDR. Residuals at CDR: mild verbal memory impairment, well-controlled seizures on medication, chronic fatigue - these support continued disability under 11.02 (epilepsy) and 12.02 (neurocognitive disorder).

Case 3: Michael, 68, Florida, primary CNS lymphoma

Michael developed rapidly progressive confusion and gait ataxia over 3 weeks in May 2026. MRI: multiple periventricular enhancing lesions with restricted diffusion. Stereotactic biopsy: diffuse large B-cell lymphoma, primary CNS. Ophthalmologic exam: bilateral vitreous involvement. CSF cytology: positive for large atypical lymphocytes.

SSDI application filed May 2026. CAL for primary CNS lymphoma triggered. Approved 11 days at Florida DDS. Induction with high-dose methotrexate + rituximab + procarbazine + vincristine + cytarabine (R-MPV/Ara-C per Memorial Sloan Kettering protocol). Achieved complete response. Consolidated with autologous stem cell transplant.

What to file with your application

1. MRI brain with contrast (and spine if leptomeningeal disease)
2. Pathology report with 2021 WHO CNS5 diagnosis and full molecular workup
3. Operative note from craniotomy or biopsy
4. Neurology and neuro-oncology consultation notes
5. Neurologic examination documenting deficits
6. Karnofsky Performance Status
7. Cognitive assessment if applicable
8. Seizure log and EEG if seizures present
9. Treatment plan (Stupp protocol, PCV, methotrexate, etc.)
10. CSF studies if leptomeningeal disease

Related reading

Full section walkthrough: Section 13.00 cancer basics. Companion cancer listings: 13.05 lymphoma, 13.14 lung, 13.20 pancreatic, 13.12 melanoma, 13.15 mesothelioma.

Frequently asked questions

Next steps

If you were diagnosed with any Grade 3 or 4 brain tumor, glioblastoma, medulloblastoma, or primary CNS lymphoma, file for SSDI immediately after pathology confirmation. The CAL fast-track will process quickly. Bring MRI, pathology report with 2021 WHO CNS5 diagnosis, and neurologic examination.