We read with great interest the SEPAR recommendations for the diagnosis and treatment of non-small cell lung cancer, published as a special issue in May 2016.1

We found it well adapted to the needs of the pulmonologist today.

However, in the subsection on minimally invasive techniques in the section dealing with cytohistological confirmation and staging studies, we were surprised to find that core needle biopsy (CNB) was not included among the techniques described.

This is a very similar procedure to transthoracic fine needle aspiration biopsy (TFNAB). The same guidance techniques, generally computed tomography (CT) and sometimes the ultrasound, are used in both. The main difference between the two procedures is the caliber of the needle, generally 18G, which can yield specimens 1 or 2cm thick, depending on the particular characteristics of the needle and the lesion. The caliber means that the needle track must always be anesthetized. The pulmonologists practicing in our hospital use both techniques. Capalbo et al.2 compared the two procedures in the diagnosis of pulmonary lesions, and reported a greater sensitivity for TFNAB (94.83%) compared to CNB (81.82%).

As confirmed by the literature, this technique has been used for years in the diagnosis of lung cancer, with an acceptable rate of complications.3 The size of the specimen is greater than that obtained by the TFNAB, making it particularly suitable for studying genetic mutations in lung tumors, such as epidermal growth factor receptor (EGFR) and anaplastic lymphoma kinase (ALK), among others. Although some centers are capable of performing these determinations from cytological samples, these laboratory techniques are not as widely implemented as studies performed on the histological sample, and as Schneider et al.4 demonstrated, CNB may be more cost-effective than TFNAB for the study of mutations.

In short, we believe that CNB should be included in paragraph 3.d on minimally invasive techniques of the SEPAR recommendations for the diagnosis and treatment of non-small cell lung cancer, along with bronchoscopy, blind transbronchial aspiration, endobronchial ultrasonography, gastrointestinal endoscopic ultrasonography, electromagnetic navigation bronchoscopy, fine needle aspiration biopsy, thoracentesis, pleural biopsy, and TFNAB, as another diagnostic procedure in non-small cell lung cancer.