Abstract
BACKGROUND: Renal cell carcinoma (RCC), the most common kidney cancer, often metastasizes to bones, lungs, liver, and the central nervous system. Intramedullary spinal metastasis from RCC is rare but can cause significant neurological deficits, necessitating prompt diagnosis and treatment through surgical intervention, radiotherapy, and immunotherapy. OBSERVATIONS: An 86-year-old man presented with progressive right lower-limb weakness and reduced sensation over 3 weeks. His medical history included a right nephrectomy for RCC 15 years earlier and L4-S1 spondylosis. Imaging identified a bleeding lesion in the conus medullaris at T11-12 and an incidental left kidney mass. Urgent surgical exploration led to a T12 laminectomy and en bloc removal of the lesion, which was confirmed as RCC metastasis. Postoperatively, the patient received focused radiotherapy and immunotherapy, showing significant motor and sensory improvement before dying 3 months later. LESSONS: This case underscores the importance of comprehensive diagnostic imaging for the accurate identification and characterization of spinal lesions. An interdisciplinary approach involving neurosurgeons, oncologists, radiologists, and pathologists is crucial for optimal treatment planning. Urgent surgical intervention can effectively address acute neurological deficits caused by intramedullary lesions. Additionally, adhering to postoperative care instructions, such as deep venous thrombosis prophylaxis, is vital to prevent fatal complications. https://thejns.org/doi/10.3171/CASE24349.