CT-guided fine-needle aspiration of lung nodules: effect on outcome of using coaxial technique and immediate cytological evaluation.

PURPOSE To evaluate the risk of pneumothorax during CT-guided fine-needle aspiration (FNA) of lung nodules with single needle and coaxial needle techniques and to assess the effect on diagnostic accuracy of immediate cytological examination of lung FNA samples. MATERIALS AND METHODS This prospective study analysed 53 patients undergoing transthoracic FNA biopsy of lung. 36 cases were performed by a radiologist using a coaxial technique, with 17 cases performed by a radiologist using a direct single-needle method. Effect of technique on occurrence of pneumothorax was recorded. FNA samples from all the patients in the study were examined immediately on-site by a cytologist or MLSO to determine whether sufficient aspirate had been obtained. Provisional diagnosis at immediate examination was compared to final diagnosis following full pathological evaluation. RESULTS Coaxial and non-coaxial groups were comparable for age and gender. Number of pleural passes was significantly lower in coaxial group (P < 0.01). Pneumothorax occurred in six (17%) of the 36 patients biopsied by coaxial technique, compared to four (24%) of the 17 patients by non-coaxial method (P = 0.55). Chest tube placement was required in four patients (11%) in the coaxial group, and two patients (12%) in the non-coaxial group (P = 0.85). A provisional cytological diagnosis was recorded for 74% of the patients in the study. 83% of the provisional reports were accurate on comparison with full pathology report. Specimen size was sufficient in 81% of cases. CONCLUSIONS The use of coaxial technique for CT-guided lung FNA biopsy reduced the number of pleural passes but did not significantly reduce the occurrence of pneumothorax. Immediate cytological examination of FNA specimens provided an accurate provisional diagnosis in the majority of cases, and should be routinely employed.