[Percutaneous needle biopsy guided with computerized tomography of the chest. Personal experience with 1,605 cases]

Fine-needle aspiration biopsy (FNAB) plays an important role in the diagnosis of lung diseases. We report the results of 1605 CT-guided chest biopsies performed September, 1992, to December, 1997, and introduce a new method for specimen storage and handling.

A lubricated flexible connection was placed between the needle and the syringe to cushion the improper movements transmitted on the needle by the operator during aspiration. 22-G needles were most frequently used. The pathologist's report included not only the presence/absence of tumor cells, but also the presence of suspicious/questionable cells, which latter finding led to another biopsy in 152 cases.

64.7% of the lesions were < or = 3 cm and 55.5% were < or = 2 cm. Pneumothorax occurred in 16.0% of cases and it required a chest tube in 5.0%. The specimens were not smeared on a slide but kept in a test tube and quickly sent to the pathologist. 84.3% of the specimens were adequate for diagnosis and special care was given to typifying microcytoma/non-microcytoma histotypes, because treatment is different. 1003 of 1313 cases (76.38%) were true positives, 192 (14.2%) true negatives, 101 (7.69%) false negatives and 17 (1.92%) false positives. Sensitivity was 90.85%, specificity 91.86% and diagnostic accuracy 91.01%. The positive and the negative predictive values were 98.3% and 65.5%, respectively.

The use of a 60 mL syringe with a flexible connection reduces the rate of complications (eg, pneumothorax, bleeding) and also the biopsy time. It also improved the sampling accuracy, cushioning any possible inappropriate movement by the operator, and finally improved the material aspiration thanks to better vacuum than with the 20-30 mL syringes which are usually placed into biopsy guns.