BACKGROUND: The role of PET in the diagnosis of paraneoplastic neurological syndromes (PNS) has previously been reported in retrospective studies, from specialized neuro-oncology units, often selecting patients with positive paraneoplastic antibodies.
OBJECTIVES: To prospectively assess the usefulness of PET in detecting malignancy in patients clinically suspected of having PNS.
METHODS: PET was performed in patients suspected of PNS within 4 weeks of the normal CT body scan. All patients were followed up.
RESULTS: Eighty patients suspected of having PNS underwent PET. 18/80 (23%) were abnormal and suspicious of malignancy. The total number of definite and probable PNS with abnormal PET was 11/18 (61%). The total number of definite and probable PNS with a normal PET was 3/62 (5%). Only 50% of patients with biopsy-proven malignancy were positive for paraneoplastic antibodies. The prevalence of abnormal PET in patients presenting with classical PNS was 41% as opposed to 21% in patients with non-classical PNS. The sensitivity and specificity of PET in diagnosing PNS was 75% and 87% respectively.
CONCLUSIONS: PET is a valuable tool in clinically suspected PNS. Its use should not be restricted to specialized neuro-oncology units or in patients with positive paraneoplastic antibodies. Positive yield is the highest amongst patients with classical PNS.
- Aged, 80 and over
- Autoimmune Diseases of the Nervous System
- Diagnosis, Differential
- Follow-Up Studies
- Health Services Accessibility
- Hospital Units
- Middle Aged
- Nervous System Diseases
- Paraneoplastic Syndromes, Nervous System
- Positron-Emission Tomography
- Prospective Studies
- Sensitivity and Specificity
- Tomography, X-Ray Computed