Fine-needle aspiration cytologic technique for lung cancer has a high potential of malignant cell spread through the tract

Background: Fine-needle aspiration cytologic technique (FNAC), a method to detect malignancy for undetermined pulmonary nodules, may have a high poten tial to spread malignant cells from the tumor to the pleural cavity. Objective: The authors assessed malignant cell spread through the needle tr act following FNAC for peripheral lung carcinoma. Materials and methods: Lung lobes resected from 20 patients during the trea tment of lung carcinoma were examined. The visceral pleura over the lung ca rcinoma was irrigated by heparinized saline solution to clean the surface, and then irrigated before FNAC and irrigated following FNAC to collect cell s on the visceral pleura, FNAC was performed once for each tumor. Papanicol au's method was employed for cytologic examination. Results: There were 15 specimens of adenocarcinoma, 4 specimens of squamous cell carcinoma, and 1 specimen of atypical carcinoid. The maximum diameter of the specimens ranged from 10 to 60 mm (median, 25 mm), Pleural indentat ion was observed in 15 samples. All results of FNAC were positive and match ed the histologic diagnosis. Pre-FNAC specimens revealed a positive maligna ncy rate of 10% (2 of 20), but post-FNAC specimens had a rate of 60% (12 of 20; p = 0.002) Conclusion: FNAC has the potential to spread malignant cells to the pleural space. Further study is needed to determine the clinical significance of t he spread of malignant cells in the pleural space.