We have read with interest the SEPAR guidelines referring to lung cancer staging,1 a document that we believe is necessary due to the need to rationalize the growing complexity of lung cancer diagnosis and treatment. Initiatives like this are extremely important for the efficient management of resources and for determining the best possible therapies for patients depending on prognostic factors, tumor stage and molecular profile.

With the intention of participating in the scientific debate that this document has initiated, we believe it is important to highlight two instances in which the published evidence does not seem to support the conclusions of the authors of the guidelines. In the first place, the use of PET/CT is recommended for the staging of patients with non-small-cell lung cancer (NSCLC) in clinical stages IA–IIIA, excluding patients with stage IIIB; however, the ACCP Evidence-Based Clinical Practice Guidelines,2 cited by the guidelines, indicate PET or PET/CT for the staging of patients with clinical stage IA–IIIB who will receive curative treatment. Likewise, the panel of experts of the International Atomic Energy Authority (IAEA)3 does not define any patient subgroup in which PET should not be used for planning radiotherapy in NSCLC. In a study of the usefulness of PET/CT for the pre-operative staging of NSCLC, Fisher et al.4 included patients with stage IIIB (33% of the cases studied) and the results of the assay do not conclude that this patient group does not benefit from the test. Finally, in a recent French multi-center study, Pommier et al.5 have demonstrated the utility of PET–CT for planning the treatment with radical radiotherapy, including patients in stage IIIB.

Second, with regard to the role that SEPAR1 attributes to PET and bone scintigraphy (BS) in the diagnosis of bone metastasis, it should be pointed out that the cited guidelines of the ACCP recommend the use of the former technique over the latter2 based on two studies that demonstrated the greater preciseness of PET over BS. A recent meta-analysis6 of 17 publications has concluded that PET or PET–CT are better imaging methods for the diagnosis of bone metastases in patients with lung cancer than BS or magnetic resonance imaging. Given the fact that the patients may also suffer a hidden visceral disease that is detectable with PET, it seems more logical to indicate this test, if available, as a first choice in studying distant metastasis staging.

In conclusion, we suggest that, based on the evidence presented, the recommendations of the SEPAR guidelines for lung cancer staging should be revised with regard to the use of PET or PET–CT in the non-invasive investigation of the mediastinum in clinical stage IIIB as well as the indication of BS instead of PET in screening for bone metastases.