Abstract:
HTML
Purpose: In suspected parotid malignancy, imaging is used for anatomical mapping and tumour staging. Others have proposed the use of imaging data to assess the nature of parotid tumours. This study reviews our experience in the imaging of primary parotid malignancy and investigates the association between imaging features and the final histological diagnosis.
Methods and Materials: Patients presenting with suspected primary parotid malignancy in the period 1993-2001 were identified from computer databases held at the departments of oncology, pathology and radiology. Patients were excluded if appropriate images were not available and if there was a suspicion of metastatic disease. Two head and neck radiologists, blinded to the histological and radiological diagnoses, systematically reviewed the images. Clinical and pathological data were retrieved from the case notes and recorded separately. The radiological appearances were then correlated with the histological findings and the results submitted to statistical inferencing using a chi-squared test of association.
Results: 42 patients with a median age of 67.5 years were included. 32 had undergone CT, 9 MR and 3 ultrasound scanning. 93% were correctly diagnosed radiologically, as having malignant parotid disease. Tumour size recorded radiologically, correlated well with the pathology specimen in 81% and tumour epicentre in 76% of cases. The radiological shape of the lesion for all modalities did not correlate with malignancy. Local infiltration and boundary definition were the most sensitive features (89% & 78% respectively). Local invasion was more accurately reported radiologically with MR rather than CT (p=0.01). The other MR features examined: T1-weighted signal, T2-weighted signal, intra-tumour fluid signal, and lymph node enlargement were unreliable indicators. Tumour boundary and contrast enhancement were the most significant findings associated with malignancy identified on CT. No significant difference in the imaging characteristics of the various tumour types could be demonstrated.
Conclusion: In our series a poorly defined tumour boundary and local invasion showed the strongest correlation with malignancy for MR and CT, MR being the most reliable modality (p=0.03; p=0.01). The sensitivity of imaging in the diagnosis of parotid malignancy was 100% for MR and 91% for CT, with an overall sensitivity of 93%. Our results support the use of imaging as a reliable means of assessment of suspected primary parotid malignancy, with MR the imaging modality of choice.
Questions about this event email: kenneth.saliba@ncl.ac.uk
Saliba MD, MSc, K,
Imaging Primary Parotid Malignancy. Radiological Society of North America 2003 Scientific Assembly and Annual Meeting, November 30 - December 5, 2003 ,Chicago IL.
http://archive.rsna.org/2003/3102028.html
