Background: In the setting of solitary pulmonary nodules (SPNs), fluorine-18 fluorodeoxyglucose positron emission tomography/computed tomography (¹⁸F-FDG-PET/CT) is considered a useful non-invasive diagnostic tool though false positive (FP) and false negative (FN) results affects accuracy due to different conditions, such as inflammatory diseases or low-uptake neoplasms. Aim of this study is to evaluate overall diagnostic performance of ¹⁸F-FDG-PET/CT for malignant pulmonary nodules. Methods: A computerized research, including published articles from 2012 and 2017, was carried out. ¹⁸F-FDG-PET/CT overall sensitivity (Se), specificity (Spe), positive likelihood ratio (PLR), negative likelihood ratio (NLR), positive predictive value (PPV), negative predictive value (NPV), diagnostic index and odds ratio were pooled. No selection-bias were found according to asymmetry test. Results: A total of twelve studies were included in the meta-analysis. The pooled Se, Spe, PLR, NLR, PPV, NPV and accuracy index (AI) with relative 95% confidence intervals (CI) were 0.819 (95% CI: 0.794–0.843), 0.624 (95% CI: 0.582–0.665), 2.190 (95% CI: 1.950–2.440), 0.290 (95% CI: 0.250–0.330), 0.802 (95% CI: 0.783–0.819), 0.652 (95% CI: 0.618–0.684) and 0.649 (95% CI: 0.625–0.673), respectively. The diagnostic odds ratio (DOR) was 7.049 with a relative 95% CI between 5.550 and 8.944. Conclusions: The results suggest ¹⁸F-FDG-PET/CT has good diagnostic accuracy in SPNs evaluation; but, it should not be considered as a discriminatory test rather than a method to be included in a clinical and diagnostic pathway.

Solitary pulmonary nodules are common radiologic findings and their detection has increased due to the introduction and improvement of diagnostics. Since a nodule can be an expression of early lung cancers, a proper classification and management are required because its treatment might lead to decreased morbidity and mortality. In this regard, prominent guidelines are available although they are characterized sometimes by discordant and misleading evidences. Furthermore, the same results of studies in the literature appear conflicting. Aim of this work is to evaluate the role of imaging through an extensive literature review but focusing on 18-fluorine fluorodeoxyglucose positron emission tomography combined with computed tomography (18F-FDG-PET/CT) in order to assess the limits and future perspectives of solitary pulmonary nodule characterization in early detection of lung cancer. Key messages Detection of solitary pulmonary nodules has increased. Management of solitary pulmonary nodules is still debated. Future perspectives of early solitary pulmonary nodule characterization.

Background: Multislice computed tomography (MSCT) increased detection of solitary pulmonary nodules (SPNs), changing the management based on radiological and clinical factors. When 18-fluorine fluorodeoxyglucose positron emission tomography combined with computed tomography (¹⁸F-FDG-PET/CT) was considered for the evaluation of nodules, the maximum standardized uptake value (SUVmax) more than 2.5 is used frequently as a cut off for malignancy. The purpose of this study is to evaluate SUVmax PET/CT and pulmonary attenuation patterns at MSCT in patients with SPN according to morphological and pathological characteristics of the lesion. Methods: A retrospective study on 1,592 SPN patients was carried out following approval by the Italian Registry of VATS Lobectomies. Results: All patients underwent VATS lobectomy. On histologic examination, 98.1% had primary or second metachronous primary lung cancers. In addition, 10.7% presented occult lymph node metastases (pN1 or pN2) on histological examination. Nodule attenuation on CT was associated with the histology of the lesion (p= 0.030); in particular, pure ground glass opacities (pGGOs) and partially solid nodules were related to adenocarcinomatous histotypes. Conversely, a significant relationship between SUVmax and age, nodule size, pathological node status (pN) was found (P=0.007, P=0.000 and P=0.002 respectively). Conclusions: Nodule attenuation can predict the histology of the lesion whereas SUVmax may relate to the propensity to lymph node metastases.

Lung cancer is one of the most frequent neoplastic diseases. To date, most lung cancer is diagnosed at an advanced stage, making it difficult to choose the diagnostic and therapeutic strategy. Surgical resection represents the best therapeutic solution. However, the best results are obtained only in the early stages of the disease. Lymph node involvement conditions the treatment (surgical or non-surgical approach). Mediastinoscopy is an effective and widely used method for mediastinal staging but does not allow us to reach many mediastinal lymph nodes. Endobronchial ultrasound/transbronchial needle aspiration (EBUS-TBNA) allows us to reach more lymph nodes and is referred to as a first-choice exam for mediastinal staging.

In the setting of a stage IV non-small cell lung cancer (NSCLC), oligometastatic patients represent a heterogeneous group whose incidence is increasing as far as with the adoption of new therapeutic regimens, the improvement of the molecular characterization assays and the increasing number of long-survivor patients. The oligometastatic state undergone a major revision with the introduction of the new TNM lung cancer staging system, being characterized by a different prognosis compared to multi-metastatic patients. Furthermore, the presence of a limited number of metastases imposes a local control especially when clonal selections occur during adjuvant therapy. In this regard, the review seeks to clarify the indications for surgical treatment by organ according to recent guidelines, by analyzing prognostic factors and outcome of patients. Although accurate patient stratification is mandatory, aggressive local control strategies represent a valid therapeutic approach in patients with oligometastatic NSCLC. At the same time, persevering with ablative strategies raises both medical and ethical issues about limits and reiteration, which certainly requires a deep reflection, being, on the other hand, in front of a metastatic disease.