Sandro Massimo Priola

Clinical Implications and Added Costs of Incidental Findings in an Early Detection Study of Lung Cancer by Using Low-Dose Spiral Computed Tomography

INTRODUCTIONnTo prospectively evaluate the frequency and spectrum of incidental findings (IF) in a 5-year lung cancer screening program with low-dose spiral computed tomography (CT) and to estimate the additional costs of their imaging workup incurred from subsequent radiologic follow-up evaluation.nnnMATERIALS AND METHODSnA total of 519 asymptomatic volunteers were enrolled. All IFs were reported and were considered clinically relevant if they required further evaluations or with clinical implications if they required more than one additional diagnostic test for characterization or medical and/or surgical intervention.nnnRESULTSnIFs were commonly found (59.2%, 307/519 participants at baseline and 5.3% per year at 5-year follow-up [123 participants of 2341 LDsCT exams performed during follow-up], with an overall rate of 26.3%). IFs were categorized as previously unknown clinically relevant in 52 (10.0%) individuals at baseline. Of these, 36 (6.9%) individuals had IFs with clinical implications (10 clinically relevant, of which 6 had clinical implications, detected during the subsequent 5-year follow-up). The most common recommendations were for additional imaging of the thyroid and kidneys. Additional imaging was mainly performed by ultrasound (43/68 [63.2%]). Subsequent surgical intervention resulted from these findings in 7 (1.5%) subjects. Six malignancies were diagnosed (rate, 0.2% per year). Costs of subsequent radiologic follow-up studies were calculated as €4644.56 [U.S.

Chemical shift and diffusion-weighted magnetic resonance imaging of the anterior mediastinum in oncology: Current clinical applications in qualitative and quantitative assessment

6575.04] at baseline and €1052.30 [U.S.

Diffusion-weighted magnetic resonance imaging of thymoma: ability of the Apparent Diffusion Coefficient in predicting the World Health Organization (WHO) classification and the Masaoka-Koga staging system and its prognostic significance on disease-free survival

1489.69] at 5-year follow-up (average added costs per participant €8.95 [U.S.

Diagnostic and functional imaging of thymic and mediastinal involvement in lymphoproliferative disorders.

12.67] and €2.25 [U.S.

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.

3.19], respectively).nnnCONCLUSIONSnLow-dose spiral CT commonly detects IFs. Some of these require further investigations to assess their clinical relevance. Although such IFs add little clinical benefit to the screening intervention, moderate incremental costs are incurred based on additional radiologic procedures generated during short-term follow-up, given the potential for positive effects on patient care.

Chemical-shift MRI of rebound thymic hyperplasia with unusual appearance and intense 18F-FDG uptake in adulthood: report of two cases

Recently, the use of magnetic resonance (MR) in clinical practice for the evaluation of the anterior mediastinum has considerably increased due to technological improvements and standardization of thoracic protocols. Currently, MR imaging is increasingly seen as a useful problem-solving modality, especially in equivocal cases at computed tomography, with the advantage of a higher contrast resolution and no radiation exposure. Chemical shift and diffusion-weighted MR are helpful in tissue characterization and present advantages over conventional MR imaging, first in providing quantitative data, without the need for the administration of contrast medium. By detecting microscopic fat in tissue, chemical shift imaging is useful for differentiating normal thymus and rebound hyperplasia from cancer tissue at diagnosis and after chemotherapy in oncologic patients, and for distinguishing lymphoid hyperplasia from thymoma in autoimmune diseases such as myasthenia gravis. Diffusion-weighted MR reflects diffusivity of water molecules within tissue and is increasingly used as a cancer biomarker, even in the thorax, for the detection and characterization of tumors, for their differentiation from benign conditions, and for monitoring treatment response. In this review, based on the current literature, technical considerations about image acquisition and data analysis of chemical shift and diffusion-weighted MR are discussed along with clinical applications in the field of benign and malignant disease of the anterior mediastinum.

Diffusion‑weighted MRI in a case of nonsuppressing rebound thymic hyperplasia on chemical‑shift MRI

AbstractObjectivesTo evaluate the usefulness of diffusion-weighted magnetic resonance for distinguishing thymomas according to WHO and Masaoka-Koga classifications and in predicting disease-free survival (DFS) by using the apparent diffusion coefficient (ADC).MethodsForty-one patients were grouped based on WHO (low-risk vs. high-risk) and Masaoka-Koga (early vs. advanced) classifications. For prognosis, seven patients with recurrence at follow-up were grouped separately from healthy subjects. Differences on ADC levels between groups were tested using Student-t testing. Logistic regression models and areas under the ROC curve (AUROC) were estimated.ResultsMean ADC values were different between groups of WHO (low-risku2009=u20091.58u2009±u20090.20u2009×u200910-3mm2/sec; high-risku2009=u20091.21u2009±u20090.23u2009×u200910-3mm2/sec; pu2009<u20090.0001) and Masaoka-Koga (earlyu2009=u20091.43u2009±u20090.26u2009×u200910-3mm2/sec; advancedu2009=u20091.31u2009±u20090.31u2009×u200910-3mm2/sec; pu2009=u20090.016) classifications. Mean ADC of type-B3 (1.05u2009±u20090.17u2009×u200910-3mm2/sec) was lower than type-B2 (1.32u2009±u20090.20u2009×u200910-3mm2/sec; pu2009=u20090.023). AUROC in discriminating groups was 0.864 for WHO classification (cut-pointu2009=u20091.309u2009×u200910-3mm2/sec; accuracyu2009=u200978.1xa0%) and 0.730 for Masaoka-Koga classification (cut-pointu2009=u20091.243u2009×u200910-3mm2/sec; accuracyu2009=u200973.2xa0%). Logistic regression models and two-way ANOVA were significant for WHO classification (odds ratio[OR]u2009=u20090.93, pu2009=u20090.007; pu2009<u20090.001), but not for Masaoka-Koga classification (ORu2009=u20090.98, pu2009=u20090.31; pu2009=u20090.38). ADC levels were significantly associated with DFS recurrence rate being higher for patients with ADCu2009≤u20091.299u2009×u200910-3mm2/sec (pu2009=u20090.001; AUROC, 0.834; accuracyu2009=u200978.0xa0%).ConclusionsADC helps to differentiate high-risk from low-risk thymomas and discriminates the more aggressive type-B3. Primary tumour ADC is a prognostic indicator of recurrence.Key Points• DW-MRI is useful in characterizing thymomas and in predicting disease-free survival.• ADC can differentiate low-risk from high-risk thymomas based on different histological compositionn • The cutoff-ADC-value of 1.309u2009×u200910-3mm2/sec is proposed as optimal cut-point for this differentiation• The ADC ability in predicting Masaoka-Koga stage is uncertain and needs further validations• ADC has prognostic value on disease-free survival and helps in stratification of risk

Thymoma of the left thymic lobe with a contralateral small pleural implant successfully detected with diffusion-weighted MRI.

Lymphoproliferative disorders of the anterior mediastinum may involve the thymus or lymph nodes as part of disseminated disease or as an isolated site. Imaging is crucial in managing patients with mediastinal lymphoma and is employed in pretreatment assessment, midtreatment evaluation of response, posttreatment restaging, and surveillance during follow-up. For decades, computed tomography (CT) has been the standard imaging technique, although in the last years, positron emission tomography (PET)-CT and magnetic resonance imaging (MRI) have been introduced. We discuss the role of different imaging techniques in the assessment of patients with mediastinal lymphoma, focusing on novel aspects of PET-CT and diffusion-weighted/MRI.

Diffusion-weighted quantitative MRI of pleural abnormalities: Intra- and interobserver variability in the apparent diffusion coefficient measurements.

To compare perfusion‐free to perfusion‐sensitive measurements of the apparent diffusion coefficient (ADC) to diagnose benign conditions from malignancies of the anterior mediastinum.

Apparent diffusion coefficient measurements in diffusion-weighted magnetic resonance imaging of the anterior mediastinum: inter-observer reproducibility of five different methods of region-of-interest positioning

Rebound thymic hyperplasia (RTH) with increased (18)F-FGD uptake at positron emission tomography (PET) computed tomography (CT) is typical of pediatric patients after chemotherapy, although it may occasionally occur in adults. At CT, RTH usually appears as a diffusely enlarged thymus with areas of fatty attenuation. We report two cases of RTH in adults detected at follow-up: both showed unusual morphology on CT and were confirmed at PET-CT as areas of strongly increased radiopharmaceutical uptake, which suggested disease recurrence. Chemical-shift magnetic resonance imaging, however, demonstrated fat infiltration within the tissue. Such finding was consistent with the diagnosis of RTH and was paramount in preventing unnecessary invasive procedures or treatments.