Magnetic resonance imaging for the study of mediastinal adenopathies in lung cancer: Comparison with standard tests.

BACKGROUND: Lung cancer is the second most common cancer in both men and women. Mediastinal lymph node involvement in these patients, determined by imaging tests, indicates prognosis and modifies therapeutic attitude. PURPOSE: The aim of this study was to analyze the diagnostic capacity of magnetic resonance imaging (MRI) in the study of the mediastinum in comparison with conventional tests (computed tomography [CT] and positron-emission tomography [PET] or PET/CT scans), taking histology as the gold standard. MATERIALS AND METHODS: An observational study was conducted on 16 patients with suspicion of primary lung cancer (June 2016 through December 2018). We studied their demographic characteristics and used CT, PET, or PET/CT scans and MRI (diffusion-weighted imaging-MRI sequence) to examine mediastinal disease and compare MRIs diagnostic yield and percentage agreement to that of conventional tests. RESULTS: As compared to CT and PET scanning, MRI displayed a very low sensitivity and a specificity of 90 and 88%, respectively; positive predictive value was 0.67 (both) and negative predictive value (NPV) was 0.28 and 0.22, respectively. MRI showed a high degree of agreement in lymph node diagnosis when compared with histology (91.2%; P = 0.001): specificity in this case was high (E = 0.94), as was the NPV (NPV = 0.97). CONCLUSIONS: The results of this study would appear to indicate that MRI could play a relevant role in mediastinal staging of lung cancer. More prospective, multicenter studies are, however, needed to be able to draw up firm recommendations about the role of MRI and its place in lung cancer staging.

Usefulness of Positron Emission Tomography in the Examination of Hilar and Mediastinal Lymphadenopathies in Patients with Suspicion of Lung Cancer.

Introduction: Lung cancer is a major health problem. Mediastinal staging performed with the aid of imaging techniques is essential for appropriate disease treatment and prognosis. Accordingly, this study aimed to ascertain the usefulness of positron emission tomography (PET) in mediastinal staging, establish the best maximum standardized uptake value (SUVmax) cutoff point, compare its usefulness to that of computed tomography (CT), and determine the influence of histological tumour subtype. Methods: We conducted a retrospective study across a period of 3 years on 128 patients with suspicion of lung cancer and analyzed their demographic and radiological characteristics using CT and PET to perform the mediastinal examination. Histology was regarded as the gold standard. Results: PET displayed a high sensitivity (95%) and negative predictive value (NPV) (92%), outperforming CT (89% and 85%, respectively). Percentage agreement with histology was also higher (0.207 and 0.241 for CT and PET, respectively; p < 0.001). Taking an SUVmax value of 0.5 as that which would ensure greatest diagnostic accuracy, S and NPV were 100%, though percentage agreement did not increase (0.189; p < 0.001). PET discriminatory power was not affected by histological tumour subtype. Conclusions: The results of our study indicate that PET might be a useful test for examination of the mediastinum in lung cancer patients. Its high NPV suggests that the absence of mediastinal uptake could be used to proceed to surgical treatment without the need for further tests or examinations. Nevertheless, studies directly aimed to answer this specific question are needed.