Chondrosarcoma of the Spinous Process: A Rare Presentation
A 34-year-old gentleman presented to us with a painless mass over the left paraspinal region incidentally noticed one year earlier. He was not aware of any previous swelling in the same region, or other swellings in the body. Examination revealed a 11×4 cm non-tender, hard, immobile swelling in the left paraspinal region of the lumbar spine (). There were no palpable swellings elsewhere in the appendicular or axial skeleton.\nPlain radiographs of the lumbar spine demonstrated. A soft tissue swelling with calcifications, there were mild osteolysis and scalloping seen over the superior border of the spinous process of third lumbar vertebra (). A radiological skeletal survey revealed multiple exostoses in both distal femora, proximal tibiae, proximal humeri, multiple ribs and scapula ranging from 1 to 2 cm in size ().\nMagnetic resonance imaging (MRI) revealed a large lobulated paraspinal mass involving the multifidus muscle extending from L2-L5 spinous process level measuring 4.7×11.5 cm hypointense in T1 weighted, and hyperintense in T2 weighted/short tau inversion recovery, with no extension into the spinal canal (). A radionucleotide technetium 99 m bone scan did not show any increased uptake at the level of the lesion.\nComputed tomography (CT) showed intra-lesional calcifications within the swelling, which arose from the spinous process of 3rd lumbar vertebra ().\nAt surgery, a 11×4×4 cm lobulated mass was seen in the left paraspinal region displacing the muscles, arising from the spinous process of L3 vertebra and indenting the lamina of L3 vertebra (). A marginal resection of the tumour and L3 spinous process was done. The postoperative period was uneventful.\nHistopathology revealed a low grade classical chondrosarcoma arising from the L3 spinous process. Curettings from the L3 lamina demonstrated the margins to be free of tumour ().\nAt one year follow-up, patient had no complaints of pain or recurrence of the swelling. Clinical examination revealed no obvious swelling at the operated site. Plain radiographs showed absent spinous process of the lumbar 3rd vertebra with no evidence of any recurrence (). MRI also confirmed the same ().