📌 Definition: Metastatic tumors that invade the spinal cord parenchyma (intramedullary compartment), often leading to rapid neurologic deterioration.
📊 Epidemiology: Very rare: <3% of CNS metastases.
More common in middle-aged to elderly patients.
Often present in patients with widespread systemic cancer.
🔍 Common Primary Tumors: Lung cancer (esp. small-cell and adenocarcinoma) – most frequent.
Breast cancer
Renal cell carcinoma
Lymphoma/leukemia
Melanoma
Occasionally from colorectal or thyroid cancers.
🧬 Pathophysiology: Spread via hematogenous route or CSF dissemination.
Often associated with leptomeningeal carcinomatosis.
Most frequently involve the cervical and thoracic cord.
⚠️ Clinical Presentation: Rapidly progressive myelopathy.
Motor weakness, sensory loss, and sphincter dysfunction.
Radicular pain may precede neurological deficits.
Symptoms evolve faster than in primary spinal cord tumors.
🧪 Diagnosis: MRI with contrast: gold standard (shows enhancing intramedullary lesion, possible edema).
CSF analysis: may show malignant cells if leptomeningeal spread.
Biopsy: rarely performed unless primary is unknown or atypical imaging.
🧠 Differential Diagnosis: Intramedullary glioma (astrocytoma, ependymoma)
Demyelinating lesions
Vascular malformations
Infectious myelitis
Radiation myelopathy
🩺 Treatment: Steroids: to reduce edema and inflammation.
Radiotherapy: primary modality, often palliative.
Surgery: rarely indicated, only if diagnosis uncertain or mass effect.
Systemic therapy: if chemosensitive tumor and systemic disease present.
📉 Prognosis: Poor, median survival ≈ 3–6 months.
Prognosis depends on systemic disease control and neurological status at diagnosis.