On-site evaluation of percutaneous CT-guided fine needle aspiration of pulmonary lesions. A study of 321 cases

Abstract

Purpose: The aim of this study was to assess the usefulness of having a cytopathologist present during percutaneous CT-guided fine needle aspiration (FNA) of pulmonary lesions.

Materials and methods: Three hundred and twenty-one FNAs of lung lesions were performed in 312 patients (218 males, 94 females; age range: 20-86 years; mean age: 66 yrs). Nodule sizes ranged from 0.5 to 8 cm. The sampling was performed by a radiologist under CT-guidance; the calibre of the needle used was 20-25 G. Smears were prepared in the Radiology Department and stained using a quick method by a cytopathologist: the sample adequacy was assessed and, if possible, a preliminary diagnosis was made. An additional FNA was requested if the first aspirate was considered diagnostically inadequate. The diagnostic accuracy was examined by reviewing the clinical data and by correlating with the histological material and the clinical outcome.

Results: Satisfactory diagnostic material was obtained in 275 of the 321 FNA (86%): 231 were malignant (72%), 8 suspicious (3%) and 36 were negative for malignancy (11%). Forty-six of the 321 specimens (14%) were considered inadequate for any diagnostic verification. An additional FNA was performed immediately in 60 cases (19%). Forty-two subjects developed pneumothorax: 21 patients (50%) of these required thoracic drainage. Blood effusion around the lesion site or adjacent to the needle path was observed in 39 patients (12%). Sensitivity was 99%, specificity was 95% and diagnostic accuracy was 99%.

Conclusions: CT guided aspiration cytology can be a safe and fast procedure for lung nodule characterisation. On-site immediate evaluation of FNA specimens can be beneficial in determining the adequacy of the aspirate and in providing accurate preliminary diagnoses of the specimens, thus allowing for rapid clinical decisions.