Nervous system lymphoma with sciatic nerve involvement in two cats diagnosed using computed tomography and ultrasound guided fine needle aspiration

Abstract

Two cats were presented with a recent history of difficulty in walking and jumping. Neurological examination was consistent with a lumbosacral or a sciatic nerve lesion in both cases with an additional C6-T2 spinal cord segment lesion in case 2. Differential diagnosis included neoplastic, inflammatory/infectious (neuritis, meningomyelitis, discospondylitis) and compressive disc disease. Computed tomography (CT) revealed an enlarged, contrast enhancing sciatic nerve from the L7-S1 intervertebral foramen, to the distal third portion of the femoral shaft. In case 2, CT also revealed an enlarged femoral nerve and an extradural mass causing mild compression of the spinal cord at T1-2 and T3-4. Ultrasonography allowed to perform fine needle aspiration of the affected sciatic nerve. Cytology was highly suggestive of indolent, small cell lymphoma in case 1, and confirmed a high-grade lymphoma in case 2, both belonging to the large granular lymphoma subtype.