Monocyte-driven atypical cytokine storm and aberrant neutrophil activation as key mediators of COVID-19 disease severity

Epidemiological and clinical reports indicate that SARS-CoV-2 virulence hinges upon the triggering of an aberrant host immune response, more so than on direct virus-induced cellular damage. To elucidate the immunopathology underlying COVID-19 severity, we perform cytokine and multiplex immune profiling in COVID-19 patients. We show that hypercytokinemia in COVID-19 differs from the interferon-gamma-driven cytokine storm in macrophage activation syndrome, and is more pronounced in critical versus mild-moderate COVID-19. Systems modelling of cytokine levels paired with deep-immune profiling shows that classical monocytes drive this hyper-inflammatory phenotype and that a reduction in T-lymphocytes correlates with disease severity, with CD8+ cells being disproportionately affected. Antigen presenting machinery expression is also reduced in critical disease. Furthermore, we report that neutrophils contribute to disease severity and local tissue damage by amplification of hypercytokinemia and the formation of neutrophil extracellular traps. Together our findings suggest a myeloid-driven immunopathology, in which hyperactivated neutrophils and an ineffective adaptive immune system act as mediators of COVID-19 disease severity.

Comparison of measured and estimated maximum skin doses during CT fluoroscopy lung biopsies

PURPOSE

To measure patient-specific maximum skin dose (MSD) associated with CT fluoroscopy (CTF) lung biopsies and to compare measured MSD with the MSD estimated from phantom measurements, as well as with the CTDIvol of patient examinations.

METHODS

Data from 50 patients with lung lesions who underwent a CT fluoroscopy-guided biopsy were collected. The CT protocol consisted of a low-kilovoltage (80 kV) protocol used in combination with an algorithm for dose reduction to the radiology staff during the interventional procedure, HandCare (HC). MSD was assessed during each intervention using EBT2 gafchromic films positioned on patient skin. Lesion size, position, total fluoroscopy time, and patient-effective diameter were registered for each patient. Dose rates were also estimated at the surface of a normal-size anthropomorphic thorax phantom using a 10 cm pencil ionization chamber placed at every 30°, for a full rotation, with and without HC. Measured MSD was compared with MSD values estimated from the phantom measurements and with the cumulative CTDIvol of the procedure.

RESULTS

The median measured MSD was 141 mGy (range 38-410 mGy) while the median cumulative CTDIvol was 72 mGy (range 24-262 mGy). The ratio between the MSD estimated from phantom measurements and the measured MSD was 0.87 (range 0.12-4.1) on average. In 72% of cases the estimated MSD underestimated the measured MSD, while in 28% of the cases it overestimated it. The same trend was observed for the ratio of cumulative CTDIvol and measured MSD. No trend was observed as a function of patient size.

CONCLUSIONS

On average, estimated MSD from dose rate measurements on phantom as well as from CTDIvol of patient examinations underestimates the measured value of MSD. This can be attributed to deviations of the patient's body habitus from the standard phantom size and to patient positioning in the gantry during the procedure.

Effect of macrolide on lung function and computed tomography (CT) score in non-cystic fibrosis bronchiectasis

BACKGROUND

The few studies addressing the effect of macrolides in non-cystic fibrosis bronchiectasis (NCFB) range from no decline to significant improvement. There are no data evaluating macrolides on CT score.

OBJECTIVES

To retrospectively evaluate the effect of initiation of macrolides on spirometry and HRCT in a NCFB population.

METHODS

We performed a word search in the electronic patient file data of the University Hospital of Leuven, Belgium, identifying all NCFB patients observed during a 41 month period and treated with macrolides. Records of all NCFB patients were manually reviewed, evaluating spirometry and CT scans, before and after/during macrolide treatment, treatment scheme, Pseudomonas status and other relevant data. CT scoring was done by using a modified version of the Brody score.

RESULTS

Evaluation of 131 patients showed a mean FEV1 improvement of 185 ml (p<0.0001) or 7.7% (p<0.0001) and a mean FVC improvement by 234 ml (p<0.001) or 7.4% (p<0.001). Smoking history, gender, Pseudomonas colonization and baseline lung function did not affect improvement in lung function. Patients with NCFB due to an immunodeficiency showed a significant larger macrolide-associated improvement in FEV1% (p=0.0075) and FVC% (p=0.0063) than patients with NCFB due to other causes. An improvement was noted in CT subscores for bronchiectasis (p=0.0053), mucus plugging (p=0.0256), peribronchial thickening (p=0.0037), parenchyma (p=0.026) and total modified Brody score (p=0.001) after versus before macrolide therapy.

CONCLUSION

Macrolides, as part of a multimodal and individualized therapy may significantly improve FVC, FEV1 and the modified Brody score in patients with NCFB, especially those with NCFB due to immunodeficiency.

Late recurrent ovarian carcinoma metastatic to the thoracic wall

Ovarian cancer is the second most common gynaecologic malignancy. Ovarian carcinomas typically metastasize to multiple sites via exfoliation, lymphatic spread or direct invasion. We present a rare case of a very late recurrence of ovarian carcinoma into the thoracic wall, heralded by thoracic pain in a patient otherwise disease-free for 23 years. This unusual and late presentation of an ovarian cancer metastasis underscores the need for continued awareness and attention to new symptoms in patients with ovarian cancer who show prolonged disease-free intervals.

Follicular bronchiolitis: a rare cause of bronchiolitis obliterans syndrome after lung transplantation: a case report

This case report is the first confirmed case of follicular bronchiolitis (FB), a rare bronchiolar disorder characterized by peribronchiolar lymphoid follicles, in a series of over 400 lung transplantations performed in our center. It is to our knowledge, the first publication describing FB after lung transplantation (LTx), presenting as chronic allograft dysfunction or bronchiolitis obliterans syndrome (BOS).

Integrated PET/CT and cancer imaging

Integrated Positron Emission Tomography/Computed Tomography (PET/CT) is an imaging technique that was introduced in clinical practice in 1998. PET/CT is the combination of two different examination techniques in one machine: Computed Tomography (CT) giving anatomic information and Positron Emission Tomography (PET) giving metabolic information. PET/CT has two major advantages: CT can be used for attenuation correction and PET/CT improves diagnostic accuracy when compared to CT and PET alone.The quality of PET/CT images depends on different parameters such as CT dose, patient respiration, and the use of intravenous (i.v.) and per oral (PO) contrast. A rapidly expanding amount of literature demonstrates the additional value of PET/CT in the diagnosis, staging, prognosis, treatment planning, assessment of treatment response and diagnosis of recurrence of many tumor types. CT increases the sensitivity of the PET/CT examination, but the most beneficial effect of having the CT data is the increase of the specificity of the PET data. PET data also helps to specify CT information.The utility of PET/CT for tumor staging, which is one of the major imaging study indication, seems to be very high, and therefore PET/CT may become the scanner of the future. Till this moment there are no many published studies about the cost-effectiveness of PET/CT. The integration of PET/CT in clinical practice will result in higher equipment running costs, but these costs are likely not to be prohibitive to the diffusion of this combined technology.

Detection of extrapulmonary lesions with integrated PET/CT in the staging of lung cancer

The aim of the present study was to assess retrospectively the additional value of positron emission tomography (PET)/computed tomography (CT) in the detection of unexpected extrapulmonary lesions in the staging of patients with a malignant pulmonary lesion in comparison with CT and PET used alone. A total of 217 patients with a pathologically proven lung tumour underwent PET/CT. CT, PET and PET/CT were evaluated in the detection of extrapulmonary lesions. These abnormalities were compared with the final diagnosis obtained from the medical records and statistical analysis was carried out. In total, 108 lesions were clinically detected. PET/CT showed a sensitivity, specificity, positive and negative predictive values and accuracy of 100, 81, 71, 100 and 87%, respectively, for the detection of extrapulmonary lesions and 92, 98, 89, 98 and 97%, respectively, for the detection of malignant extrapulmonary lesions. PET/CT was significantly better than CT and PET used alone. Conventional staging work-up has a poor sensitivity in detecting second primary cancers or unexpected metastases. The detection of malignant extrapulmonary lesions is necessary for correct tumour staging. By combining both metabolic and anatomical information, positron emission tomography/computed tomography is able to depict more unexpected extrapulmonary lesions than computed tomography and positron emission tomography used alone, and positron emission tomography/computed tomography provides more additional information of malignancy or benignancy of lesions detected with one of the two imaging modalities alone.

Integrated PET/CT in lung cancer imaging: history and technical aspects

Integrated PET/CT is a new anatomo-metabolic imaging modality combining two different techniques: Computed Tomography (CT) that provides very detailed anatomic information and Positron Emission Tomography (PET) that provides metabolic information. Integrated PET/CT has several advantages. One of the advantages is the use of CT data for attenuation correction that is significantly faster compared to that in conventional PET systems. Due to the use of CT data for attenuation correction, artefacts can be generated on PET images related to the use of intravenous or oral CT contrast agents, CT beam-hardening artefacts due to metallic implants and motion artefacts (respiratory motion, physical bowel motion, cardiac motion). The purpose of this review is to discuss some technical considerations concerning the CT protocol that can be used for PET/CT in lung cancer imaging and to give a short overview of the initial results of staging of non-small cell lung cancer (NSCLC).

Additional value of CT-fluoroscopic biopsy of pulmonary lesions: a retrospective study of 69 patients

The purpose of this retrospective study was to evaluate the diagnostic accuracy of CT-fluoroscopic transthoracic biopsy of pulmonary lesions related to their localization and size. The complication rate was also evaluated. Between January 2003 and June 2004, we performed seventy-two CT-fluoroscopic transthoracic biopsies in sixty-nine patients. Lesions were subdivided in subpleural, peripheral and central lesions. The lesions were also subdivided concerning their diameter. Fifty three lesions (77%) had a final diagnosis of malignancy and 13 lesions (19%) had a final benign diagnosis. CT-fluoroscopic transthoracic biopsy had an overall diagnostic accuracy of 84.4%, sensitivity of 80.7%, specificity of 100%, positive predictive value of 100% and negative predictive value of 54.5%. For lesions between 1 and 3 cm the accuracy was 78.5% for lesions greater than 3 cm 87%. Only one lesion was smaller than 1 cm, this lesion was true positive. There were no false-positive findings. Pneumothoraces were observed in only 7 patients (10%) and there was only 1 small postpuncture hemothorax (1.7%). CT-fluoroscopic biopsy of pulmonary lesions has a good diagnostic accuracy with a very low complication rate. The accuracy is higher for larger lesions, but there is no significant difference for subpleural and peripheral lesions.

Additional value of integrated PET-CT in the detection and characterization of lung metastases: correlation with CT alone and PET alone

The purpose was evaluating retrospectively the additional value of integrated positron emission tomography (PET) and computed tomography (CT) in the detection of pulmonary metastases in comparison with CT and PET alone. Fifty-six lung nodules, divided into three groups according their size, detected in 24 consecutive patients with a known primary tumor were retrospectively evaluated with integrated PET-CT, CT and PET. The nature of these nodules was determined by either histopathology or a follow-up of at least 6 months. The CT and PET images of the integrated PET-CT were evaluated separately by a radiologist and a nuclear medicine physician, the integrated PET-CT images were evaluated by a chest radiologist and nuclear medicine physician in consensus. The investigators were asked to search lung nodules and to determine whether these nodules were metastases or not. Sensitivity and accuracy for CT, PET and integrated PET-CT for characterization of all pulmonary nodules were, respectively: 100%, 90%, 100% and 57%, 55%, 55%. There was no significant difference in the characterization of pulmonary nodules between integrated PET-CT and CT alone (P=1.000) and PET alone (P=0.1306). An accurate evaluation is only possible for lesions larger than 1 cm.

Additional value of PET-CT in the staging of lung cancer: comparison with CT alone, PET alone and visual correlation of PET and CT

Integrated positron emission tomography (PET) and computed tomography (CT) is a new imaging modality offering anatomic and metabolic information. The purpose was to evaluate retrospectively the accuracy of integrated PET-CT in the staging of a suggestive lung lesion, comparing this with the accuracy of CT alone, PET alone and visually correlated PET-CT. Fifty patients undergoing integrated PET-CT for staging of a suggestive lung lesion were studied. Their tumor, node, metastasis (TNM) statuses were determined with CT, PET, visually correlated PET-CT and integrated PET-CT. These TNM stages were compared with the surgical TNM status. Integrated PET-CT was the most accurate imaging technique in the assessment of the TNM status. Integrated PET-CT predicted correctly the T status, N status, M status and TNM status in, respectively, 86%, 80%, 98%, 70% versus 68%, 66%,88%, 46% with CT, 46%, 70%, 96%, 30% with PET and 72%, 68%, 96%, 54% with visually correlated PET-CT. T status and N status were overstaged, respectively, in 8% and 16% with integrated PET-CT, in 20% and 28% with CT, in 16% and 20% with PET, in 12% and 20% with visually correlated PET-CT and understaged in 6% and 4% with integrated PET-CT, versus 12% and 6% with CT, 38% and 10% with PET and 12% with visually correlated PET-CT. Integrated PET-CT improves the staging of lung cancer through a better anatomic localization and characterization of lesions and is superior to CT alone and PET alone. If this technique is not available, visual correlation of PET and CT can be a valuable alternative.

Virtual Bronchoscopy: Accuracy and Usefulness—An Overview

Multidetector CT generated virtual bronchoscopy (VB) represents one of the most recent developments in three-dimensional (3D) visualization techniques which allows a 3D evaluation of the airways down to the sixth- to seventh-generation. In comparison with real bronchoscopy, VB has some advantages: it is a non-invasive procedure that can visualize areas inaccessible to the flexible bronchoscope. Virtual bronchoscopy is able to evaluate bronchial stenosis and obstruction caused by both endoluminal pathology (tumor, mucus, foreign bodies) and external compression (anatomical structures, tumor, lymph nodes), can be helpful in the preoperative planning of stent placement and can be used to evaluate surgical sutures after lung transplantations, lobectomy or pneumectomy. In children, in some indications, VB can replace fiber optical bronchoscopy (FB) when this technique is considered too invasive. Finally, VB can also be used to evaluate anatomical malformations and bronchial variants. Virtual bronchoscopy is accurate but its accuracy is not 100% because false-positives and false-negatives occur. Virtual bronchoscopy contributes to a better understanding of tracheo-bronchial pathology. Fiber optical bronchoscopy will, without doubt, remain the golden standard but it can be expected that in the near future, the technique of VB will find a place in the daily routine.

Multidetector CT-generated virtual bronchoscopy: an illustrated review of the potential clinical indications

Multidetector computed tomography-generated virtual bronchoscopy (VB) is a recent technical development that allows visualisation of the lumen and wall of the trachea and proximal part of the bronchial tree. A dynamic image is produced that resembles what is seen with fibreoptic bronchoscopy (FB). Although the technique has not yet reached daily clinical practice and it can never replace FB, performing VB can be useful in well-defined clinical situations. In this paper, the value and limitations of virtual bronchoscopy will be reviewed, to illustrate the potential role of virtual bronchoscopy in the evaluation of trachea and bronchial tree pathology.

Positron emission tomography for assessment of the response to induction radiochemotherapy in locally advanced oesophageal cancer

AIMS

This prospective study was designed to determine the utility of 18F-labelled deoxyglucose (FDG) in positron emission tomography (PET) (FDG-PET) for assessing the response to neoadjuvant chemoradiation therapy (CRT) in locally advanced oesophageal tumours.

PATIENTS AND METHODS

Thirty-six patients with locally advanced oesophageal cancer (clinical T4 stage) without organ metastases, underwent FDG-PET before and 1 month after CRT. Patients were classified as major responders by serial FDG-PET when the post-CRT PET demonstrated a strong reduction of FDG uptake at the primary tumour site (>80% reduction of tumour-to-liver uptake ratio) without any abnormal FDG uptake elsewhere in the body. PET response was compared with histology obtained during post-induction transthoracic oesophagectomy.

RESULTS

A strong correlation was found between the extent of lymph node (LN) involvement as shown by the pre-CRT PET and the major response rate (P = 0.001): such response occurred in nine of 11 N0M0 patients (82%), in three of nine N(1-2)M0 patients (33%) and in two of 16 patients (13%) with distant lymphatic spread. Such a correlation was not found for computed tomography or endoscopic ultrasonography. The sensitivity of serial FDG-PET for a major CRT response was 10 of 14 (71%), its specificity 18 of 22 (82%). The concordance between the response assessment by PET and histopathology was 78%. The median survival time after CRT of PET major responders compared with PET non-major responders was 16.3 months and 6.4 months, respectively. The metabolic response as measured by serial FDG-PET is a stronger prognostic factor for overall survival (P = 0.002) than the extent of LN involvement seen on the pretreatment FDG-PET (P = 0.087).

CONCLUSIONS

These data indicate that CRT response as assessed by serial FDG-PET is strongly correlated with pathological response and survival.

Computed tomography in staging for lung cancer

Computed tomography (CT) provides the most detailed imaging information, hence it is generally used as a routine imaging procedure in the tumour, node, metastasis (TNM)-staging of patients with lung cancer. However, despite the continuously ongoing process of improvement in CT scanning in which today's CT scanners combine fast acquisition, fast data reconstruction and high detail, the technique has important limitations. CT can, in some cases, very accurately show tumour extent within, and predict spread beyond the lung. However, the question of whether the tumour has invaded the chest wall or the mediastinum and, if so, whether it is still potentially surgically curable often remains unanswered. In addition, the only sign for predicting lymph node involvement using CT is enlargement. Many studies have shown that this sign is not very reliable. CT is also, with success, being used to evaluate distant metastases although other techniques such as ultrasound and magnetic resonance imaging can have similar or higher accuracies. Despite these well-known limitations, computed tomography will most likely stay the routine imaging procedure for determining resectability and for assessing intra- and extrathoracic spread of lung cancer. The improvement in technology will probably result a better T-staging. The role of computed tomography in nodal staging remains important. It offers the surgeon a road map of the lymph nodes and guides towards the nodes that need biopsy. Combining computed tomography with positron emission tomography, when it becomes more widely available, will add functional images to the detail of computed tomography and will not only improve nodal staging but will probably also allow a better evaluation of distant metastasis and reduce the number of unnecessary interventional procedures.

Paravertebral and diaphragmatic mass: an ectopic location of bronchogenic cyst

Bronchogenic cysts constitute one area of the broad spectrum of developmental anomalies of the primitive foregut. They arise from anomalous budding of the primitive tracheobronchial tube and are commonly located in the mediastinum or the lung parenchyma, closely related to the tracheobronchial tree. In rare cases, they can migrate to subpleural, pericardial, paravertebral and cervical locations, if embryological connections with their parent bronchus are lost. Plain chest radiography and computed tomography have been the primary imaging modalities used for diagnosis. Computed tomography is frequently associated with misleading information with respect to the cyst density. Magnetic resonance imaging has been shown to be useful in the differential diagnosis of cystic mediastinal masses. We present a patient with two asymptomatic bronchogenic cysts found at a distance from the tracheobronchial tree.

Histopathologic validation of lymph node staging with FDG-PET scan in cancer of the esophagus and gastroesophageal junction: A prospective study based on primary surgery with extensive lymphadenectomy

OBJECTIVE

To assess the value of positron emission tomography with 18fluorodeoxyglucose (FDG-PET) for preoperative lymph node staging of patients with primary cancer of the esophagus and gastroesophageal junction.

SUMMARY BACKGROUND DATA

FDG-PET appears to be a promising tool in the preoperative staging of cancer of the esophagus and gastroesophageal junction. Recent reports indicate a higher sensitivity and specificity for detection of stage IV disease and a higher specificity for diagnosis of lymph node involvement compared with the standard use of computed tomography and endoscopic ultrasound.

METHODS

Forty-two patients entered the prospective study. All underwent attenuation-corrected FDG-PET imaging of the neck, thorax, and upper abdomen, a spiral computed tomography scan, and an endoscopic ultrasound. The gold standard consisted exclusively of the histology of sampled nodes obtained by extensive two-field or three-field lymphadenectomies (n = 39) or from guided biopsies of suspicious distant nodes indicated by imaging (n = 3).

RESULTS

The FDG-PET scan had lower accuracy for the diagnosis of locoregional nodes (N1-2) than combined computed tomography and endoscopic ultrasound (48% vs. 69%) because of a significant lack of sensitivity (22% vs. 83%). The accuracy for distant nodal metastasis (M+Ly), however, was significantly higher for FDG-PET than the combined use of computed tomography and endoscopic ultrasound (86% vs. 62%). Sensitivity was not significantly different, but specificity was greater (90% vs. 69%). The FDG-PET scan correctly upstaged five patients (12%) from N1-2 stage to M+Ly stage. One patient was falsely downstaged by FDG-PET scanning.

CONCLUSIONS

FDG-PET scanning improves the clinical staging of lymph node involvement based on the increased detection of distant nodal metastases and on the superior specificity compared with conventional imaging modalities.

The utility of positron emission tomography for the diagnosis and staging of recurrent esophageal cancer

OBJECTIVE

To study the utility of whole-body positron emission tomography with (18)F-fluoro-deoxy-D -glucose (FDG-PET) for the evaluation of recurrence after curative resection of cancer of the esophagus or gastroesophageal junction.

METHODS

Forty-one patients with a clinical or radiologic suspicion of recurrent disease underwent conventional diagnostic work-up, including a spiral computed tomographic scan, an endoscopic ultrasound, and a dedicated whole-body FDG-PET. PET lesions were classified as equivocal or suspicious recurrence. The conventional diagnostic work-up and PET findings were correlated with pathology or with radiologic and clinical follow-up. Equivocal lesions were classified as positive.

RESULTS

Forty recurrences were found in 33 patients. The lesions were perianastomotic (n = 9), regional (n = 12), and at distant sites (n = 19). For the diagnosis of a perianastomotic recurrence, the sensitivity, specificity, and accuracy of FDG-PET were 100%, 57%, and 74%, versus 100%, 93%, and 96% for conventional diagnostic work-up, respectively (P = not significant). False-positive PET lesions were found in patients with a progressive anastomotic stenosis requiring repetitive endoscopic dilatation. For the diagnosis of regional and distant recurrences, the sensitivity, specificity, and accuracy of PET were 94%, 82%, and 87%, versus 81% (P = not significant), 82% (P = not significant), and 81% (P =.0771) for conventional diagnostic work-up. All false-positive PET lesions (n = 4) had been reported as equivocal. On a patient base, PET provided additional information in 11 of 41 (27%) patients. A major impact on diagnosis was found in 5 patients with equivocal or negative findings on complete diagnostic work-up in whom PET provided a true-positive diagnosis. In 5 other patients the diagnosis was staged upward from localized to extended recurrent disease, and in 1 patient with an equivocal complete diagnostic work-up, PET correctly excluded malignancy.

CONCLUSION

FDG-PET allows a highly sensitive diagnosis and accurate whole-body staging of symptomatic recurrent esophageal cancer. Further studies in asymptomatic patients are needed to assess the potential benefit on survival.

Utility of positron emission tomography for the staging of patients with potentially operable esophageal carcinoma

PURPOSE

A prospective study of preoperative tumor-node-metastasis staging of patients with esophageal cancer (EC) was designed to compare the accuracy of 18-F-fluoro-deoxy-D-glucose (FDG) positron emission tomography (PET) with conventional noninvasive modalities.

PATIENTS AND METHODS

Seventy-four patients with carcinomas of the esophagus (n = 43) or gastroesophageal junction (n = 31) were studied. All patients underwent attenuation-corrected FDG-PET imaging, a spiral computed tomography (CT) scan, and an endoscopic ultrasound (EUS).

RESULTS

FDG-PET demonstrated increased activity in the primary tumor in 70 of 74 patients (sensitivity: 95%). False-negative PET images were found in four patients with T1 lesions. Thirty-four patients (46%) had stage IV disease. FDG-PET had a higher accuracy for diagnosing stage IV disease compared with the combination of CT and EUS (82% v 64%, respectively; P: =.004). FDG-PET had additional diagnostic value in 16 (22%) of 74 patients by upstaging 11 (15%) and downstaging five (7%) patients. Thirty-nine (53%) of the 74 patients underwent a 2- or 3-field lymphadenectomy in conjunction with primary curative esophagectomy. In these patients, tumoral involvement was found in 21 local and 35 regional or distant lymph nodes (LN). For local LN, the sensitivity of FDG-PET was lower than EUS (33% v 81%, respectively; P: =.027), but the specificity may have been higher (89% v 67%, respectively; P: = not significant [NS]). For the assessment of regional and distant LN involvement, compared with the combined use of CT and EUS, FDG-PET had a higher specificity (90% v 98%, respectively; P: =. 025) and a similar sensitivity (46% v 43%, respectively; P: = NS).

CONCLUSION

PET significantly improves the detection of stage IV disease in EC compared with the conventional staging modalities. PET improves diagnostic specificity for LN staging.

Radiology of lung trauma

Trauma caused by motor vehicle accidents is the leading cause of death among people under the age of 40 years. Pulmonary injuries can be caused by direct trauma to the lungs or can be related to indirect effects of the trauma. The most important pulmonary injuries include lung contusion, pulmonary laceration, aspiration, lung atelectasis, and ARDS. Injuries caused by direct trauma may be visible either at the side of trauma or on the opposite side: the contre-coup effect. Conventional chest film is the most important imaging technique for initial evaluation and follow-up of patients with trauma to the lungs. However, CT is more sensitive and specific to detect and identify pulmonary lesions.

The impact of (18)F-fluoro-2-deoxy-D-glucose positron emission tomography (FDG-PET) lymph node staging on the radiation treatment volumes in patients with non-small cell lung cancer

PURPOSE

(18)F-fluoro-2-deoxy-D-glucose positron emission tomography (FDG-PET) combined with computer tomography (PET-CT) is superior to CT alone in mediastinal lymph node (LN) staging in non-small cell lung cancer (NSCLC). We studied the potential impact of this non-invasive LN staging procedure on the radiation treatment plan of patients with NSCLC.

PATIENTS AND METHODS

The imaging and surgical pathology data from 105 patients included in two previously published prospective LN staging protocols form the basis for the present analysis. For 73 of these patients, with positive LN's on CT and/or on PET, a theoretical study was performed in which for each patient the gross tumour volume (GTV) was defined based on CT and on PET-CT data. For each GTV, the completeness of tumour coverage was assessed, using the available surgical pathology data as gold standard. A more detailed analysis was done for the first ten consecutive patients in whom the PET-CT-GTV was smaller than the CT-GTV. Theoretical radiation treatment plans were constructed based on both CT-GTV and PET-CT-GTV. Dose-volume histograms for the planning target volume (PTV), for the total lung volume and the lung volume receiving more than 20 Gy (V(lung(20))), were calculated.

RESULTS

Data from 988 assessed LN stations were available. In the subgroup of 73 patients with CT or PET positive LN's, tumour coverage improved from 75% when the CT-GTV was used to 89% with the PET-CT-GTV (P=0.005). In 45 patients (62%) the information obtained from PET would have led to a change of the treatment volumes. For the ten patients in the dosimetry study, the use of PET-CT to define the GTV, resulted in an average reduction of the PTV by 29+/-18% (+/-1 SD) (P=0.002) and of the V(lung(20)) of 27+/-18% (+/-1 SD) (P=0.001).

CONCLUSION

In patients with NSCLC considered for curative radiation treatment, assessment of locoregional LN tumour extension by PET will improve tumour coverage, and in selected patients, will reduce the volume of normal tissues irradiated, and thus toxicity. This subgroup of patients could then become candidates for treatment intensification.

Role of radiology in lung transplantation

Lung transplantation has been used successfully since 1983 as treatment for terminal stages of chronic progressive lung disease of various origin. Based on the primary pathology, a single lung transplant, a double lung transplant or a heart-lung transplant is performed. The importance of radiology in detecting postoperative complications is well known. This article gives a short overview of the most common complications after lung transplantation with special attention to the specific radiological features and most suited examination techniques. We preferred grouping the complications in function of the affected structure. Postoperative standard radiography of the thorax is performed daily during admission (first recumbent, later standing) and regularly after release from the hospital. Computerised tomography and high-resolution CT of the chest are performed on specific indications. Other less frequently used radiological techniques are transoesophageal ultrasound, pulmonary artery angiography and fluoroscopy.

[Selective embolization of an aneurysm in a massive angiomyolipoma of the kidney]

Forty to 80% of patients with tuberous sclerosis exhibit renal angiomyolipomas which are often multiple and bilateral. Renal ultrasonography has a low sensitivity and a low specificity in the diagnosis of renal angiomyolipomas. Some patients have so many angiomyolipomas that ultrasonography indicates a confluence of angiomyolipomatous tissue throughout the kidney, in which case the size of a separate angiomyolipoma is difficult to estimate and the actual size may be underestimated. However it is an important tool in the follow-up of smaller lesions. With CT and magnetic resonance imaging, the diagnosis of these angiomyolipomas can always be confirmed due to the characteristic fat component. In addition, a better visualisation of the extension of the lesions can be obtained. Once the diagnosis of angiomyolipoma has been established a sonographic follow-up every 6 months is mandatory and feasible. Renal angiomyolipomas larger than 3.5 cm in diameter have a substantial risk for severe hemorrhage which should be treated by selective embolization.