Correlation between CT findings and thoracoscopic diagnosis in diffuse pleural disease.

OBJECTIVE: Computed Tomography (CT) is considered part of the routine diagnostic workup for pleural malignancy. The definitive diagnosis of pleural malignancy depends upon histological confirmation by pleural biopsy. The aim of this study is to assess the sensitivity and specificity of CT, in view of the latest imaging technologies, in detecting pleural malignancy compared to definitive histology achieved via thoracoscopy (VATS). MATERIALS AND METHODS: We included in this retrospective study 90 patients (36 F, 54 M) with suspected pleural malignancy  evaluated in our Institution with CT scan who received a definitive diagnosis after VATS biopsy. Unaware of histopathologic diagnoses CT scans were evaluated by a junior and two experts thoracic radiologist. Conclusions were reached by consensus. RESULTS: We evaluated all CT signs suggestive for malignant pleural diseases: pleural thickening > 10 mm (Se 0,41 , Sp 0,79); nodular thickening (Se 0,86, Sp 0,75); circumferential thickening (Se 0,79, Sp 0,69); irregular pleural thickening (Se 0,77, Sp 0,91); mediastinal involvement (Se 0,88, Sp 0,64); costal involvement (Se 0,89, Sp 0,60); diaphragmatic involvement (Se 0,88, Sp 0,53). Furthermore, the diagnostic performance of additional CT features was evaluated: concomitant costal, mediastinal and diaphragmatic pleura lesions (Se 0,84, Sp 0,69); nodular/irregular thickening with mediastinal pleural involvement (Se 0,83, Sp 0,90); nodular/irregular thickening with diaphragmatic pleural involvement (Se 0,81, Sp 0,90). CONCLUSIONS: CT confirms its central role in the pleura malignancy. The high sensibility, respect to previous studies, especially in the presence of nodular pleural thickening, may lead to reconsider at least partly the diagnostic pathway of diffuse pleural disease, avoiding the use of VATS in patients not eligible for surgery, in favor of US or CT guided core biopsy.

Diagnostic Imaging and workup of Malignant Pleural Mesothelioma.

Malignant pleural mesothelioma is the most frequent primary neoplasm of the pleura and its incidence is still increasing.This tumor has a strong association with exposure to occupational or environmental asbestos, often after a long latent period of 30-40 years.Plain chest radiography (CXR) is usually the first-line radiologic examination, but the radiographic findings are nonspecific due to its limited contrast resolution and they need to be complemented by other imaging modalities such as computed tomography (CT), magnetic resonance Imaging (MRI), Positron emission tomography-computed tomography (PET-CT) and ultrasound (US).The aim of this paper is to describe the imaging  features of this malignancy, underlining the peculiarity of CXR, CT, MRI, PET-CT and US and also focusing on diagnostic workup, based on the literature evidence and according to our experience.

Diffusion-weighted quantitative MRI to diagnose benign conditions from malignancies of the anterior mediastinum: Improvement of diagnostic accuracy by comparing perfusion-free to perfusion-sensitive measurements of the apparent diffusion coefficient.

PURPOSE: To compare perfusion-free to perfusion-sensitive measurements of the apparent diffusion coefficient (ADC) to diagnose benign conditions from malignancies of the anterior mediastinum. MATERIALS AND METHODS: Seventy-six subjects were divided into a "benign conditions" group (A, n = 44) and a "malignancies" group (B, n = 32), based on histological findings. diffusion-weighted magnetic resonance imaging (DW-MRI) was performed at b of 0/150/800 sec/mm(2) . The ADCs were obtained on an ADC map by including (perfusion-sensitive = ADCb0-800 ) and excluding (perfusion-free = ADCb150-800 ) the b = 0 sec/mm(2) . The Mann-Whitney U-test was used to detect differences in ADCb0-800 compared with ADCb150-800 values between all cases, benign conditions, and malignancies. The same test was used to evaluate differences in ADCs between the two groups for each type of measurement (ADCb0-800 and ADCb150-800 ), and receiver-operating characteristic (ROC) curves were obtained to evaluate discrimination abilities with comparison of areas-under-ROC-curves (AUROC). Optimal cutpoints for discrimination between groups were determined by the Youden-Index with computation of accuracy. RESULTS: The median ADCb0-800 was significantly greater compared with ADCb150-800 for all cases (P = 0.0014), benign conditions (P = 0.0412), and malignancies (P = 0.0001). The median percentage of increase was 5.30% for group-A and 22.39% for group-B (P < 0.0001). AUROC of ADC in discriminating between groups was significantly greater for ADCb150-800 (0.932) compared with ADCb0-800 (0.831) (P = 0.001). The optimal cutpoint for distinction between groups was 1.52 × 10(-3) mm(2) /sec (sensitivity = 93.7%, specificity = 88.6%, accuracy = 90.8%) for ADCb150-800 and 1.75 × 10(-3) mm(2) /sec (sensitivity = 75.0%, specificity = 79.5%, accuracy = 77.6%) for ADCb0-800 . CONCLUSION: The use of perfusion-free ADC measurements significantly improves diagnostic accuracy of DW-MRI in differentiating benign conditions from malignancies of the anterior mediastinum. J. Magn. Reson. Imaging 2016;44:758-769.