Answer of May 2015


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Clinical History:

A 56-year-old female patient of end-stage renal disease on peritoneal dialysis presented with a 6-month history of progressive low back pain. No focal neurological symptom otherwise. The neurological examination was unremarkable.

X Rays of lumbosacral spine:

X Rays of lumbosacral spine 1X Rays of lumbosacral spine 2

Plain CT Lumbosacral spine:


Selected reformatted images at L1:

Plain CT - 1

Plain CT - 2Plain CT - 3

MRI Lumbosacral spine :

MRI - 1MRI - 2

Axial T2W images at L1 (LEFT) and L3 (RIGHT) respectively:

Axial - 1Axial - 2



Brown tumour of the spine resulting in compression of conus medullaris and cauda equina.


While brown tumours of the appendicular skeleton are well-known to be associated with hyperparathyroidism (primary > secondary), brown tumour of the spine complicated by cord / cauda equina compression is very rare.  Most cases reported in literature are associated with chronic renal disease in adults.  The patients may present with back pain of insidious onset, and progressive weakness related to cord compression, or acute back pain and paraplegia related to pathological fractures.


Imaging findings include lytic solitary or multifocal sharply demarcated expansile lesions on radiographs, CT and MRI. On bone scan they are MDP-avid and may mimic metastases. Correlation with serum parathyroid hormone levels, sestamibi scan for parathyroid lesions and other radiographic features of hyperparathyroidism would be helpful. However, since the differential diagnoses of these lesions include amyloidosis, metastases and myeloma, which are much more common in renal patients, the diagnosis of brown tumour should only be made by exclusion. CT-guided biopsy for obtaining histological diagnosis is often warranted.


For treatment, the main aim is to optimize control of the hyperparathyroidism. Like other brown tumours, these spinal lesions may resolve 1-2 years after subtotal parathyroidectomy. Medical treatment (eg cinacalcet) alone is often considered inadequate for prevention of tumour growth or recurrence. Urgent decompression surgery may be warranted if patients present with acute neurological deficits.