Computed tomography of abdominal neurogenic tumours.

Abdominal and pelvic neurogenic tumours are uncommon neoplasms in adults apart from those tumours found in patients with neurofibromatosis. Malignant degeneration occurs in 2.4-29% of neurofibromatosis. Biopsy of neurofibromas can be complicated by sensorimotor nerve deficit. Distinction of malignancy by imaging may circumvent biopsies of asymptomatic benign neurogenic tumours. Benign neurogenic neoplasm is suspected on CT scan if the tumour is in the region of known nerve ganglia or pathway, and is well demarcated, solid, homogeneous, hypodense relative to muscle, and enhances with contrast material. Malignant neurogenic tumours are often large, irregular, infiltrative, and necrotic with heterogeneous contrast enhancement. Computed tomography is valuable in distinguishing malignant from benign neurogenic neoplasms, predicting resectability, detecting distant metastases, and evaluating response to treatment.