We read with interest the paper by Targowski et al.1 Suspicious lung infiltrations such as malignant tumours are always difficult to diagnose in clinical practice. Transthoracic fine needle biopsy (TFNB) may be a useful procedure despite a high risk of false negative results. To improve the accuracy of the technique, telomerase activity in combination with TFNB was investigated in the study by Targowski et al.

We suggest that alternative options such as positron tomography scanning (CT-PET) should be evaluated, which may provide better imaging quality and accurate guidance for performing TFNB, increasing the accuracy of lung cancer diagnosis.

In the Continuing Observation of Smoking Subjects (COSMOS) study recently published by Veronesi et al2 involving 5200 current or former smokers, CT-PET had a sensitivity of 100% in the diagnosis of solid pulmonary nodules of 10 mm of more. In this study, TFNB was not part of the clinical routine. In contrast, the sensitivity of the combination of TFNB with telomerase activity used by Targowski et al was lower at 89.3% and the mean size of suspected lesions was not described.