Ferritin is associated with the severity of lung involvement but not with worse prognosis in patients with COVID-19: data from two Italian COVID-19 units.

The coronavirus 2019 disease (COVID-19) is characterised by a heterogeneous clinical presentation, a complex pathophysiology and a wide range of imaging findings, depending on disease severity and time course. We conducted a retrospective evaluation of hospitalized patients with proven SARS-CoV-2 infection, clinical signs of COVID-19 and computed tomography (CT) scan-proven pulmonary involvement, in order to identify relationships between clinical, serological, imaging data and disease outcomes in patients with COVID-19. Clinical and serological records of patients admitted to two COVID-19 Units of the Abruzzo region in Italy with proven SARS-CoV-2 pulmonary involvement investigated with CT scan, assessed at the time of admission to the hospital, were retrospectively evaluated. Sixty-one patients (22 females and 39 males) of median age 65 years were enrolled. Fifty-six patients were discharged while death occurred in 5 patients. None of the lung abnormalities detected by CT was different between discharged and deceased patients. No differences were observed in the features and extent of pulmonary involvement according to age and gender. Logistic regression analysis with age and gender as covariates demonstrated that ferritin levels over the 25th percentile were associated with the involvement of all 5 pulmonary lobes (OR = 14.5, 95% CI 2.3-90.9, p = 0.004), the presence of septal thickening (OR = 8.2, 95% CI 1.6-40.9, p = 0.011) and the presence of mediastinal lymph node enlargement (OR = 12.0, 95% CI 1.1-127.5, p = 0.039) independently of age and gender. We demonstrated that ferritin levels over the 25th percentile are associated with a more severe pulmonary involvement, independently of age and gender and not associated with disease outcomes. The identification of reliable biomarkers in patients with COVID-19 may help guiding clinical decision, tailoring therapeutic approaches and ultimately improving the care and prognosis of patients with this disease.

Under-reporting of cardiovascular findings on chest CT.

PURPOSE: It is unclear whether (and, to what extent) radiologists look at and report cardiovascular abnormalities on non-cardio-synchronized standard chest computed tomography (CT). In this study, the frequency and the reporting rate of cardiovascular findings in chest CT examinations were retrospectively assessed. MATERIALS AND METHODS: This study was approved by the institutional review board of each participating center. Four academic centers provided data on 447 subjects who underwent non-ECG-synchronized chest CT examinations for evaluating pulmonary fibrosis (161/447, 36 %), suspected pulmonary embolism (140/447, 31.3 %), or lung cancer staging (146/447, 32.7 %). A total of 220/447 (53.7 %) and 227/447 CT (46.3 %) examinations were evaluated and reported by junior and senior chest radiologists, respectively. Two radiologists with training in cardiac imaging reviewed the same chest CT images looking for the presence of incidental cardiovascular abnormalities using a preformatted score sheet. Inter-observer agreement was assessed using the kappa coefficient of agreement (k). RESULTS: Inter-observer agreement between the study reviewers was moderate to good (0.4-0.73) for most of the incidental cardiovascular findings. At least one incidental cardiovascular finding not documented in the original report was identified by the study reviewers in 225/409 (55 %) of chest CT examinations. A total of 168/266 (63.2 %) potentially clinically significant cardiovascular findings were unreported in the original reports of 177/447 (39.6 %) subjects (p < 0.0001). Senior radiologists tended to more frequently report coronary artery calcification (p = 0.0006), cardiac valves calcification (p = 0.0003), and ascending aorta enlargement (p = 0.01) compared to junior radiologists. CONCLUSIONS: Several cardiovascular abnormalities can be reliably identified on standard chest CT. Yet, they are often under-reported, even when they might be relevant to the patient's work-up.

Comparison between whole-body MRI and Fluorine-18-Fluorodeoxyglucose PET or PET/CT in oncology: a systematic review.

BACKGROUND: The aim of the article is to systematically review published data about the comparison between positron emission tomography (PET) or PET/computed tomography (PET/CT) using Fluorine-18-Fluorodeoxyglucose (FDG) and whole-body magnetic resonance imaging (WB-MRI) in patients with different tumours. METHODS: A comprehensive literature search of studies published in PubMed/MEDLINE, Scopus and Embase databases through April 2012 and regarding the comparison between FDG-PET or PET/CT and WB-MRI in patients with various tumours was carried out. RESULTS: Forty-four articles comprising 2287 patients were retrieved in full-text version, included and discussed in this systematic review. Several articles evaluated mixed tumours with both diagnostic methods. Concerning the specific tumour types, more evidence exists for lymphomas, bone tumours, head and neck tumours and lung tumours, whereas there is less evidence for other tumour types. CONCLUSIONS: Overall, based on the literature findings, WB-MRI seems to be a valid alternative method compared to PET/CT in oncology. Further larger prospective studies and in particular cost-effectiveness analysis comparing these two whole-body imaging techniques are needed to better assess the role of WB-MRI compared to FDG-PET or PET/CT in specific tumour types.

Food residue granuloma mimicking metastatic disease on FDG-PET/CT.

A 31-year-old woman presenting with acute abdomen underwent an emergency Hartmann's procedure for fecal peritonitis due to perforated adenocarcinoma of the left colon. Shortly after a 7-month course of adjuvant chemotherapy, follow-up contrast-enhanced CT showed multiple peritoneal and hepatic nodules, showing focal intense and homogeneous FDG uptake on FDG-PET/CT, highly suspected for recurrence of disease. Excisional biopsy of the nodules revealed foreign body granulomas made up of alimentary materials surrounded by a fibrous wall. We report a unique case of a false-positive finding secondary to food residues mimicking metastatic disease on FDG-PET in a patient with colon cancer.

Usefulness of (18)F-FDG PET/CT in disease extent and treatment response assessment in a patient with syphilitic aortitis.

A 40-year-old man was admitted to our hospital for surgical treatment of aortic insufficiency and coronary ostial stenosis. Histopathology and serological tests revealed a syphilitic aortitis. F-FDG PET/CT was performed to assess the extent of aortitis, showing increased radiopharmaceutical uptake along the ascending aortic wall. A repeated FDG PET/CT after antibiotic therapy showed a markedly reduced uptake in the aortic wall, suggesting resolution of the infection according to clinical and serological data. This case highlights the usefulness of FDG PET/CT for the assessment of disease extent and treatment response in patients with syphilitic aortitis.

Low-dose radiotherapy as a chemo-potentiator of a chemotherapy regimen with pemetrexed for recurrent non-small-cell lung cancer: a prospective phase II study.

PURPOSE: Low-dose radiotherapy (LDR) (<50 cGy) induces enhanced cell killing in vitro via the hyper-radiation sensitivity phenomenon. Aim of this study was to evaluate the safety and efficacy of a palliative regimen combining pemetrexed and LDR (as a chemopotentiator) on patients affected by recurrent non-small-cell lung cancer (NSCLC). METHODS AND MATERIALS: Eligible patients had an ECOG performance status ≤2, one prior chemotherapy regimen for advanced NSCLC, adequate organ function, measurable lesions. Patients received pemetrexed (500 mg/m(2) IV) and concurrent LDR (40 cGy bid on days 1 and 2) delivered to target pulmonary or metastatic disease. This cycle was repeated fourfold every 21 days. The accrual was determined by the single proportion powered analysis (α=0.05, power=0.8) with H0 ("bad" response probability, 9% according to literature) and H1 ("good" response probability, 35% ongoing study); 19 is the number required. RESULTS: Nineteen patients with stage III and IV disease were enrolled. Only one patient experienced neutropenia grade 4. All patients are evaluable for clinical response of irradiated lesion: overall response rate was 42%. CONCLUSIONS: Low-dose radiotherapy combined with pemetrexed has a similar toxicity profile to chemotherapy alone. The response rate of this novel approach is encouraging, since it was higher than what was reported for pemetrexed alone (42% versus 9.1%). Additional scientific investigation of this new treatment paradigm is warranted.

Usefulness of whole-body fluorine-18-fluorodeoxyglucose positron emission tomography in patients with neurofibromatosis type 1: a systematic review.

Aim. To systematically review the role of positron emission tomography (PET) with fluorine-18-fluorodeoxyglucose (FDG) in patients with neurofibromatosis type 1 (NF1). Methods. A comprehensive literature search of published studies regarding FDG-PET and PET/CT in patients with NF1 was performed. No beginning date limit and language restriction were used; the search was updated until December 2011. Only those studies or subsets in studies including whole-body FDG-PET or PET/CT scans performed in patients with NF1 were included. Results. We identified 12 studies including 352 NF1 patients. Qualitative evaluation was performed in about half of the studies and semiquantitative analysis, mainly based on different values of SUV cutoff, in the others. Most of the studies evaluated the role of FDG-PET for differentiating benign from malignant peripheral nerve sheath tumors (MPNSTs). Malignant lesions were detected with a sensitivity ranging between 100% and 89%, but with lower specificity, ranging between 100% and 72%. Moreover, FDG-PET seems to be an important imaging modality for predicting the progression to MPNST and the outcome in patients with MPNST. Two studies evaluated the role of FDG-PET in pediatric patients with NF1. Conclusions. FDG-PET and PET/CT are useful methods to identify malignant change in neurogenic tumors in NF1 and to discriminate malignant from benign neurogenic lesions.

¹8F-fluoro-deoxy-glucose focal uptake in very small pulmonary nodules: fact or artifact? Case reports.

BACKGROUND: 18F-fluoro-deoxy-glucose (18 F-FDG) positron emission tomography integrated/combined with computed tomography (PET-CT) provides the best diagnostic results in the metabolic characterization of undetermined solid pulmonary nodules. The diagnostic performance of 18 F-FDG is similar for nodules measuring at least 1 cm and for larger masses, but few data exist for nodules smaller than 1 cm. CASE PRESENTATION: We report five cases of oncologic patients showing focal lung 18 F-FDG uptake on PET-CT in nodules smaller than 1 cm. We also discuss the most common causes of 18 F-FDG false-positive and false-negative results in the pulmonary parenchyma.In patient 1, contrast-enhanced CT performed 10 days before PET-CT did not show any abnormality in the site of uptake; in patient 2, high-resolution CT performed 1 month after PET showed a bronchiole filled with dense material interpreted as a mucoid impaction; in patient 3, contrast-enhanced CT performed 15 days before PET-CT did not identify any nodules; in patients 4 and 5, contrast-enhanced CT revealed a nodule smaller than 1 cm which could not be characterized. The 18 F-FDG uptake at follow-up confirmed the malignant nature of pulmonary nodules smaller than 1 cm which were undetectable, misinterpreted, not recognized or undetermined at contrast-enhanced CT. CONCLUSION: In all five oncologic patients, 18 F-FDG was able to metabolically characterize as malignant those nodules smaller than 1 cm, underlining that: 18 F-FDG uptake is not only a function of tumor size but it is strongly related to the tumor biology; functional alterations may precede morphologic abnormalities. In the oncologic population, especially in higher-risk patients, PET can be performed even when the nodules are smaller than 1 cm, because it might give an earlier characterization and, sometimes, could guide in the identification of alterations missed on CT.

Myocardial perfusion single-photon emission tomography (SPET) and positron emission tomography-computed tomography (PET-CT) imaging for congenitally corrected transposition of great arteries.

Congenitally corrected transposition of great arteries (ccTGA) consists of both atrioventricular and ventriculo-arterial discordance. In patients with ccTGA, the pulmonary artery arises from the left ventricle, whereas the aorta arises from the right ventricle. The burden of the systemic blood pressure on the right ventricle involves an increased risk of coronary artery disease (CAD) and, as a long-term consequence, myocardial hypertrophy and gradual failure. This report describes the case of an adult patient affected by ccTGA who was referred for an episode of atypical chest pain while at rest. First-line diagnostic examinations were inconclusive. Myocardial perfusion single-photon emission tomography (SPET) was performed to exclude CAD, but the congenital abnormalities of the patient's heart made interpretation of the images particularly difficult. A perfusion positron emission tomography-computed tomography (PET-CT) scan with (13)N-ammonia then was suggested, which unmasked an unexpected artifact. The case report demonstrates that hybrid imaging techniques such as SPET-CT and PET-CT should be used systematically when CAD is suspected for patients with abnormal anatomy of the heart, including ccTGA.

Integrated imaging of non-small cell lung cancer recurrence: CT and PET-CT findings, possible pitfalls and risk of recurrence criteria.

OBJECTIVES: To review the role of imaging in the diagnosis of recurrent disease in previously treated non-small cell lung cancer (NSCLC) and discuss the imaging pitfalls. METHODS: A comprehensive review of published literature on CT and PET imaging of NSCLC recurrence was performed. Diagnostic and prognostic values are discussed. Representative imaging examples are illustrated. RESULTS: Up to 30% of NSCLC recurrences present as loco-regional, involving treated hemithorax and ipsilateral lymph nodes, while 70% present as metachronous distant metastases. CT and PET-CT play an important role in the early detection of recurrence; indications for imaging vary depending on pathological features. CONCLUSION: Imaging plays a central role in the identification of recurrence and may predict prognosis. KEY POINTS: Lung cancer recurs after surgery in 30% to 75% of patients. CT and PET-CT are crucial in identification of loco-regional recurrence. Knowledge of potential pitfalls is essential, especially for parenchymal or nodal recurrence. CT can diagnose metastases but further examinations (PET-CT, MRI) are often needed. Morphological and functional imaging criteria may help in predicting recurrence.

Usefulness of fluorine-18 fluorodeoxyglucose PET/computed tomography in diagnosis of aortitis and treatment response evaluation in a patient with aortic prosthesis.

We report the case of an 82-year-old man with aortic prosthesis inflammation in whom fluorine-18 fluorodeoxyglucose (FDG) positron emission tomography/computed tomography has been useful in the detection of the cause of fever of unknown origin. We also describe the correlation between decrease of FDG uptake in the vascular prosthesis after treatment and clinical improvement with normalization of the serological levels of inflammatory markers.

Lung abnormalities at multimodality imaging after radiation therapy for non-small cell lung cancer.

Three-dimensional (3D) conformal radiation therapy (CRT) and stereotactic body radiation therapy (SBRT) are designed to deliver the maximum therapeutic radiation dose to the tumor, allowing improved local disease control, while minimizing irradiation of surrounding normal structures. The complex configuration of the multiple beams that deliver the radiation dose to the tumor in 3D CRT and SBRT produces patterns of lung injury that differ in location and extent from those seen after conventional radiation therapy. Radiation-induced changes in lung tissue after 3D CRT and SBRT occur within the radiation portals. The imaging appearance of irradiated tissues varies according to the time elapsed after the completion of therapy, with acute-phase changes of radiation pneumonitis represented by ground-glass opacities and consolidation and with late-phase changes of radiation fibrosis manifesting as volume loss, consolidation, and traction bronchiectasis. Knowledge of treatment timelines and radiation field locations, as well as familiarity with the full spectrum of possible radiation-induced lung injuries after 3D CRT and SBRT, is important to correctly interpret the abnormalities that may be seen at computed tomography (CT). Differential diagnoses in this context might include infections, lymphangitic carcinomatosis, local recurrence of malignancy, and radiation-induced tumors. The integration of morphologic information obtained at CT with metabolic information obtained at positron emission tomography is helpful in distinguishing radiation-induced parenchymal abnormalities from residual, recurrent, and new cancers. Thus, multimodality follow-up imaging may lead to substantial changes in disease management.

Is there a role for fluorine 18 fluorodeoxyglucose-positron emission tomography and positron emission tomography/computed tomography in evaluating patients with mycobacteriosis? A systematic review.

OBJECTIVE: This study was designed to review the emerging role of fluorine 18 fluorodeoxyglucose (¹8F-FDG)-positron emission tomography (PET) CT/computed tomography (PET/CT) in patients with mycobacteriosis. METHODS: A comprehensive literature search of published studies through October 2010 in PubMed/MEDLINE database regarding ¹8F-FDG-PET and PET/CT in patients with mycobacteriosis was performed. RESULTS: Ultimately, we identified 16 studies comprising a total of 220 patients with mycobacteriosis. Main findings of the included studies are presented. CONCLUSIONS: (1) Mycobacteriosis commonly causes increased ¹8F-FDG uptake; therefore, positive ¹8F-FDG-PET results should be interpreted with caution in differentiating benign from malignant abnormalities. (2) ¹8F-FDG-PET and PET/CT are potentially useful in detecting sites of Mycobacterium infection. (3) Dual-phase ¹8F-FDG-PET is not useful for the differential diagnosis between malignant lesions and sites of Mycobacterium infection. (4) ¹8F-FDG-PET and PET/CT are useful for the evaluation of disease activity and in monitoring response to therapy in patients with mycobacteriosis. (5) Dual-tracer PET and PET/CT are potentially useful for presumptive diagnosis of solitary pulmonary nodules.

Necrotizing pneumonia and sepsis due to Clostridium perfringens: a case report.

Clostridia are uncommon causes of pleuropulmonary infection. Clostridial species infecting the pleuropulmonary structures characteristically cause a necrotizing pneumonia with involvement of the pleura. Most cases have iatrogenic causes usually due to invasive procedures into the pleural cavity, such as thoracentesis or thoracotomy, or penetrating chest injuries. Rarely clostridia pleuropulmonary infections are not related to these factors. The clinical course of pleuropulmonary clostridial infections can be very variable, but they may be rapid and fatal. We report a rare case of necrotizing pneumonia and sepsis due to Clostridium perfringens not related to iatrogenic causes or injuries in an 82 years old woman.

Aging and the respiratory system.

In the elderly, the chest without evident pathology is characterized by findings that occupy a sort of "no man's land" between the normal and the pathologic. Aging results in physiologic modifications that must be recognized so as not to be interpreted erroneously as pathologies. On the other hand, the elderly tend to become ill more frequently and multipathologies are more frequent. Image diagnostics is a key element in the clarification of often blurry clinical pictures, which may make early diagnosis possible, a great advantage to timely treatment. In this sense, knowledge of heart/lung interactions makes it possible to obtain, from the onset, radiologic and clinical signs of the two physiopathologic models prevalent in the elderly, the "cardiac lung" and the "pulmonary heart."

Lung cancer screening with spiral CT.

Lung cancer is the main cause of death from malignancies due to the high prevalence and adverse prognosis when diagnosis is established in symptomatic patients. With early diagnosis, survival is far better; this led to perform some trials of screening in subjects at high risk with chest X-ray since 1970 but outcomes were contrasting. The technological evolution with the introduction of spiral CT and low dose techniques in the last decade led to a new interest in lung cancer screening. Numerous trials were performed and several diagnostic algorithms based on the dimensional and densitometric analysis of CT-evidenced nodules were designed. In spite of the encouraging outcome achieved so far, the high rate of false positives, the high costs and the use of ionizing radiation advise caution at least until a decreased mortality rate from lung cancer is evidenced.

The evolution of digital radiography: from storage phosphors to flat-panel detectors.

At present, conventional radiology is being slowly but inexorably replaced by digital radiology. While storage phosphors introduced approximately twenty years ago are now routinely used, flat panel systems are increasingly popular. There are two types of flat panels: those with direct X-ray conversion to electric charge and those where there is initial X photon conversion to visible light from optical amorphous silicon photodiode coupling for conversion to electric charge. The charge is therefore amplified and digital signal conversion is obtained with an analog-to-digital converter. One of the main advantages of Computed Radiography is the separation of image acquisition processing and display. Acquisition systems of digital images with image processing techniques allow the operator to adapt the image characteristics to the clinical requirements. Contrast value and image brightness can be changed soon after acquisition to optimize visualization before printing or transfer to the workstation for postprocessing. Image processing can be interactive, directly on the system consolle. To digital data various processing algorithms can be applied as high spatial frequency enhancement through the construction of the shadow mask. The new digital systems have improved the quality of conventional radiological images as compared to the screen-film and storage phosphor systems with shorter times of procedures and lower exposure dose to patients, while the diagnostic potentialities of the acquired image are enhanced.