Chronic thromboembolic pulmonary hypertension and impairment after pulmonary embolism: the FOCUS study.

AIMS: To systematically assess late outcomes of acute pulmonary embolism (PE) and to investigate the clinical implications of post-PE impairment (PPEI) fulfilling prospectively defined criteria. METHODS AND RESULTS: A prospective multicentre observational cohort study was conducted in 17 large-volume centres across Germany. Adult consecutive patients with confirmed acute symptomatic PE were followed with a standardized assessment plan and pre-defined visits at 3, 12, and 24 months. The co-primary outcomes were (i) diagnosis of chronic thromboembolic pulmonary hypertension (CTEPH), and (ii) PPEI, a combination of persistent or worsening clinical, functional, biochemical, and imaging parameters during follow-up. A total of 1017 patients (45% women, median age 64 years) were included in the primary analysis. They were followed for a median duration of 732 days after PE diagnosis. The CTEPH was diagnosed in 16 (1.6%) patients, after a median of 129 days; the estimated 2-year cumulative incidence was 2.3% (1.2-4.4%). Overall, 880 patients were evaluable for PPEI; the 2-year cumulative incidence was 16.0% (95% confidence interval 12.8-20.8%). The PPEI helped to identify 15 of the 16 patients diagnosed with CTEPH during follow-up (hazard ratio for CTEPH vs. no CTEPH 393; 95% confidence interval 73-2119). Patients with PPEI had a higher risk of re-hospitalization and death as well as worse quality of life compared with those without PPEI. CONCLUSION: In this prospective study, the cumulative 2-year incidence of CTEPH was 2.3%, but PPEI diagnosed by standardized criteria was frequent. Our findings support systematic follow-up of patients after acute PE and may help to optimize guideline recommendations and algorithms for post-PE care.

ERS statement on chest imaging in acute respiratory failure.

Chest imaging in patients with acute respiratory failure plays an important role in diagnosing, monitoring and assessing the underlying disease. The available modalities range from plain chest X-ray to computed tomography, lung ultrasound, electrical impedance tomography and positron emission tomography. Surprisingly, there are presently no clear-cut recommendations for critical care physicians regarding indications for and limitations of these different techniques.The purpose of the present European Respiratory Society (ERS) statement is to provide physicians with a comprehensive clinical review of chest imaging techniques for the assessment of patients with acute respiratory failure, based on the scientific evidence as identified by systematic searches. For each of these imaging techniques, the panel evaluated the following items: possible indications, technical aspects, qualitative and quantitative analysis of lung morphology and the potential interplay with mechanical ventilation. A systematic search of the literature was performed from inception to September 2018. A first search provided 1833 references. After evaluating the full text and discussion among the committee, 135 references were used to prepare the current statement.These chest imaging techniques allow a better assessment and understanding of the pathogenesis and pathophysiology of patients with acute respiratory failure, but have different indications and can provide additional information to each other.

European Respiratory Society International Congress, Paris, 2018: highlights from the Clinical Assembly.

This article contains highlights and a selection of the scientific advances from the European Respiratory Society's Clinical Assembly (Assembly 1 and its five respective groups) that were presented at the 2018 European Respiratory Society International Congress in Paris, France. The most relevant topics from each of the groups will be discussed, covering a wide range of areas including clinical problems, rehabilitation and chronic care, thoracic imaging, interventional pulmonology, and general practice and primary care. The newest research, actual data and highlight sessions will be discussed.

Chronic thromboembolic pulmonary hypertension (CTEPH): Updated Recommendations from the Cologne Consensus Conference 2018.

Chronic thromboembolic pulmonary hypertension (CTEPH) is a subgroup of pulmonary hypertension that differs from all other forms of PH in terms of its pathophysiology, patient characteristics and treatment. For implementation of the European Guidelines on Diagnosis and Treatment of Pulmonary Hypertension in Germany, the Cologne Consensus Conference 2016 was held and last updated in spring of 2018. One of the working groups was dedicated to CTEPH, practical and controversial issues were commented and updated. In every patient with suspected PH, CTEPH or chronic thromboembolic disease (CTED, i.e. symptomatic residual vasculopathy without pulmonary hypertension) should be excluded. Primary treatment is surgical pulmonary endarterectomy (PEA) in a multidisciplinary CTEPH centre. Inoperable patients or patients with persistent or recurrent CTEPH after PEA are candidates for targeted drug therapy. There is increasing experience with balloon pulmonary angioplasty (BPA) for inoperable patients; this option, like PEA, is reserved for specialised centres with expertise in this treatment method.

European Respiratory Society International Congress 2017: highlights from the Clinical Assembly.

This article contains highlights and a selection of the scientific advances from the European Respiratory Society's Clinical Assembly (Assembly 1 and its six respective groups) that were presented at the 2017 European Respiratory Society International Congress in Milan, Italy. The most relevant topics from each of the groups will be discussed, covering a wide range of areas including clinical problems, rehabilitation and chronic care, thoracic imaging, interventional pulmonology, diffuse and parenchymal lung diseases, and general practice and primary care. In this comprehensive review, the newest research and actual data as well as award-winning abstracts and highlight sessions will be discussed.

Clinical highlights from the 2016 European Respiratory Society International Congress.

This article contains highlights and a selection of the scientific advances from the European Respiratory Society (ERS) Clinical Assembly (Assembly 1) and its six respective groups (Groups 1.1-1.6) that were presented at the 2016 ERS International Congress in London, UK. The most relevant topics for clinicians will be discussed, covering a wide range of areas including clinical problems, rehabilitation and chronic care, thoracic imaging, interventional pulmonology, diffuse and parenchymal lung diseases, and general practice and primary care. In this comprehensive review, the newest research and actual data will be discussed and put into perspective.

In Silico Oncology: Quantification of the In Vivo Antitumor Efficacy of Cisplatin-Based Doublet Therapy in Non-Small Cell Lung Cancer (NSCLC) through a Multiscale Mechanistic Model.

The 5-year survival of non-small cell lung cancer patients can be as low as 1% in advanced stages. For patients with resectable disease, the successful choice of preoperative chemotherapy is critical to eliminate micrometastasis and improve operability. In silico experimentations can suggest the optimal treatment protocol for each patient based on their own multiscale data. A determinant for reliable predictions is the a priori estimation of the drugs' cytotoxic efficacy on cancer cells for a given treatment. In the present work a mechanistic model of cancer response to treatment is applied for the estimation of a plausible value range of the cell killing efficacy of various cisplatin-based doublet regimens. Among others, the model incorporates the cancer related mechanism of uncontrolled proliferation, population heterogeneity, hypoxia and treatment resistance. The methodology is based on the provision of tumor volumetric data at two time points, before and after or during treatment. It takes into account the effect of tumor microenvironment and cell repopulation on treatment outcome. A thorough sensitivity analysis based on one-factor-at-a-time and latin hypercube sampling/partial rank correlation coefficient approaches has established the volume growth rate and the growth fraction at diagnosis as key features for more accurate estimates. The methodology is applied on the retrospective data of thirteen patients with non-small cell lung cancer who received cisplatin in combination with gemcitabine, vinorelbine or docetaxel in the neoadjuvant context. The selection of model input values has been guided by a comprehensive literature survey on cancer-specific proliferation kinetics. The latin hypercube sampling has been recruited to compensate for patient-specific uncertainties. Concluding, the present work provides a quantitative framework for the estimation of the in-vivo cell-killing ability of various chemotherapies. Correlation studies of such estimates with the molecular profile of patients could serve as a basis for reliable personalized predictions.

Functional Characterization of Patients with Chronic Thromboembolic Disease.

BACKGROUND: Patients with chronic thromboembolic pulmonary disease (CTED) have persistent pulmonary vascular obstruction and exercise intolerance without pulmonary hypertension at rest and may benefit from pulmonary endarterectomy. However, up to now, CTED has been poorly characterized. OBJECTIVES: This study aimed to analyze the exercise capacity and limiting factors in CTED. METHODS: We compared right heart catheterization and cardiopulmonary exercise test results of patients with CTED [mean pulmonary artery pressure (mPAP) at rest <25 mm Hg, n = 10], chronic thromboembolic pulmonary hypertension (CTEPH, n = 31) and a control group (n = 41) presenting with dyspnea but normal pulmonary vascular imaging and excluded pulmonary hypertension. RESULTS: Subjects with CTED show a reduced oxygen uptake [median 76/interquartile range (IQR) 22% pred.] and work rate (median 76/IQR 21 W). The work rate was significantly lower compared to control subjects (p = 0.04) but not significantly different from CTEPH patients (p = 0.66). Oxygen pulse and breathing reserve were normal. CTED subjects showed decreased end-tidal CO2 at anaerobic threshold (28.4/4.3 mm Hg), an elevated VE/VCO2 slope (42.5/23.5), breathing equivalents (EQO2 32.0/8.7, EQCO2 39.5/8.8), alveolar-capillary oxygen gradient (34.7/15.5 mm Hg) and capillary end-tidal carbon dioxide gradient (8.8/5.7 mm Hg) compared to control subjects (p < 0.001). The degree of limitation was similar to that in CTEPH. CONCLUSIONS: Despite an mPAP of <25 mm Hg, subjects with CTED show objective functional impairment and similar limitations to patients with CTEPH. Functional limitation is characterized by gas exchange disturbance and ineffective ventilation.

Assessment of operability by means of CTPA and perfusion SPECT in patients with chronic thromboembolic pulmonary hypertension.

BACKGROUND: Chronic thromboembolic pulmonary hypertension (CTEPH) can potentially be cured by pulmonary thrombendarterectomy (PEA), the criteria for differentiation between operable and non-operable patients are not standardized. PURPOSE: To retrospectively evaluate the value of rigidly registered computed tomography pulmonary angiography (CTPA) and single photon emission CT (SPECT) in differentiating for PEA. MATERIAL AND METHODS: Forty-nine patients with CTEPH (21 men; age, 58 ± 13 years) were evaluated by an interdisciplinary expert board using all available diagnostic information and their consensus statement as gold standard. For SPECT a lobe based perfusion score was visually assessed using the score of 0 (lack of perfusion) to 1 (normal perfusion) calculating percentage of vascular obstruction (PVO). By CTPA, vascular obstruction index (OI) of central, peripheral, and global PA-bed were determined. The accuracy of the alignment between CTPA and SPECT was determined by fusion score (FS) ranging from 1 (no alignment) to 5 (exact alignment). Angiography provided PA pressure (PAP), pulmonary vascular resistance (PVR), and PA wedge pressure (PAWP). Receiver operating characteristics (ROC) analysis was performed. RESULTS: Twenty-nine patients were considered surgically amenable, and 20 patients were inoperable. Mean PAP, PVR, and PAWP were 48 ± 11 mmHg, 868 ± 461 dynes*sec*cm(-5), and 11 ± 5 mmHg, without differences between surgical and non-surgical patients (P > 0.5). In all patients accurate registration was reached (FS = 4.1 ± 0.7; range, 2-5). PVO and central OI separated PEA-amenable patients (P ≤ 0.001) resulting in the area under the curve of 0.828 (cutoff for PVO: 37.8% with a sensitivity of 82% and specificity of 79%) and 0.755 (cutoff for central OI: 29% with a sensitivity and specificity of 86.2% and 79%) for operability. CONCLUSION: An accurate interpretation of rigidly registered CTPA and perfusion SPECT may contribute to stratification of operability in patients with CTEPH.

PET-based delineation of tumour volumes in lung cancer: comparison with pathological findings.

PURPOSE: The objective of the study was to validate an adaptive, contrast-oriented thresholding algorithm (COA) for tumour delineation in (18)F-fluorodeoxyglucose (FDG) positron emission tomography (PET) for non-small cell lung cancer (NSCLC) in comparison with pathological findings. The impact of tumour localization, tumour size and uptake heterogeneity on PET delineation results was also investigated. METHODS: PET tumour delineation by COA was compared with both CT delineation and pathological findings in 15 patients to investigate its validity. Correlations between anatomical volume, metabolic volume and the pathology reference as well as between the corresponding maximal diameters were determined. Differences between PET delineations and pathological results were investigated with respect to tumour localization and uptake heterogeneity. RESULTS: The delineated volumes and maximal diameters measured on PET and CT images significantly correlated with the pathology reference (both r > 0.95, p < 0.0001). Both PET and CT contours resulted in overestimation of the pathological volume (PET 32.5 ± 26.5%, CT 46.6 ± 27.4%). CT volumes were larger than those delineated on PET images (CT 60.6 ± 86.3 ml, PET 48.3 ± 61.7 ml). Maximal tumour diameters were similar for PET and CT (51.4 ± 19.8 mm for CT versus 53.4 ± 19.1 mm for PET), slightly overestimating the pathological reference (mean difference CT 4.3 ± 3.2 mm, PET 6.2 ± 5.1 mm). PET volumes of lung tumours located in the lower lobe were significantly different from those determined from pathology (p = 0.037), whereas no significant differences were observed for tumours located in the upper lobe (p = 0.066). Only minor correlation was found between pathological tumour size and PET heterogeneity (r = -0.24). CONCLUSION: PET tumour delineation by COA showed a good correlation with pathological findings. Tumour localization had an influence on PET delineation results. The impact of tracer uptake heterogeneity on PET delineation should be considered carefully and individually in each patient. Altogether, PET tumour delineation by COA for NSCLC patients is feasible and reliable with the potential for routine clinical application.

Simultaneous occurrence of typical carcinoid and non-small-cell lung cancer in the same lung lobe: value of nuclear medicine.

The present report demonstrates the usefulness of nuclear medicine in differentiating different pulmonary tumors. A 79-year-old woman presented with a suspicious peripherally located lesion of the right lower lobe in the costophrenic angle. During bronchoscopic evaluation, a centrally located intrabronchial lesion was found, which was positive on a subsequent In-111 octreotide examination. The histologic examination of this central lesion confirmed a typical bronchial carcinoid. The FDG PET examination revealed a high uptake just in the peripherally located lesion, which was then confirmed to be non-small-cell lung cancer. This is the first report of nuclear medicine methods evaluating simultaneous occurrence of a typical bronchial carcinoid and a non-small-cell lung cancer in the same lung lobe.

F-18-FDG-PET confined radiotherapy of locally advanced NSCLC with concomitant chemotherapy: results of the PET-PLAN pilot trial.

PURPOSE: The integration of fluoro-deoxy-D-glucose positron emission tomography (FDG-PET) in the process of radiotherapy (RT) planning of locally advanced non-small-cell lung cancer (NSCLC) may improve diagnostic accuracy and minimize interobserver variability compared with target volume definition solely based on computed tomography. Furthermore, irradiating only FDG-PET-positive findings and omitting elective nodal regions may allow dose escalation by treating smaller volumes. The aim of this prospective pilot trial was to evaluate the therapeutic safety of FDG-PET-based RT treatment planning with an autocontour-derived delineation of the primary tumor. METHODS AND MATERIALS: Eligible patients had Stages II-III inoperable NSCLC, and simultaneous, platinum-based radiochemotherapy was indicated. FDG-PET and computed tomography acquisitions in RT treatment planning position were coregistered. The clinical target volume (CTV) included the FDG-PET-defined primary tumor, which was autodelineated with a source-to-background algorithm, plus FDG-PET-positive lymph node stations. Limited by dose restrictions for normal tissues, prescribed total doses were in the range of 66.6 to 73.8 Gy. The primary endpoint was the rate of out-of-field isolated nodal recurrences (INR). RESULTS: As per intent to treat, 32 patients received radiochemotherapy. In 15 of these patients, dose escalation above 66.6 Gy was achieved. No Grade 4 toxicities occurred. After a median follow-up time of 27.2 months, the estimated median survival time was 19.3 months. During the observation period, one INR was observed in 23 evaluable patients. CONCLUSIONS: FDG-PET-confined target volume definition in radiochemotherapy of NSCLC, based on a contrast-oriented source-to-background algorithm, was associated with a low risk of INR. It might provide improved tumor control because of dose escalation.

Impact of rigid and nonrigid registration on the determination of 18F-FDG PET-based tumour volume and standardized uptake value in patients with lung cancer.

PURPOSE: Assessment of the metabolically active tumour tissue by FDG PET is evolving for use in the diagnosis of non-small-cell lung cancer (NSCLC), in the planning of radiotherapy, and in follow-up and response evaluation. For exact evaluation accurate registration of PET and CT data is required. The registration process is usually based on rigid algorithms; however, nonrigid algorithms are increasingly being used. The influence of the registration method on FDG PET-based standardized uptake value (SUVmax) and metabolic tumour volume (MTV) definition has not yet been evaluated. We compared intra- and interindividual differences in SUV and MTV between rigid- and nonrigid-registered PET and CT acquired during different breathing manoeuvres. METHODS: The study group comprised 28 radiotherapy candidates with histologically proven NSCLC who underwent FDG PET acquisition and three CT acquisitions (expiration - EXP, inspiration - INS, mid-breath-hold - MID). All scans were registered with both a rigid (R) and a nonrigid (NR) procedure resulting in six fused datasets: R-INS, R-EXP, R-MID, NR-INS, NR-EXP and NR-MID. For the delineation of MTVs a contrast-oriented contouring algorithm developed in-house was used. To accelerate the delineation a semiautomatic software prototype was utilized. RESULTS: Tumour mean SUVmax did not differ for R and NR registration (R 17.5 ± 7, NR 17.4 ± 7; p=0.2). The mean MTV was higher by 3 ± 12 ml (p=0.02) in the NR group than in the R group, as was the mean tumour diameter (by 0.1 ± 0.2 cm; p<0.01). With respect to the three different breathing manoeuvres, there were no differences in MTV in the R group (p > 0.7). In intraindividual comparison there were no significant differences in MTVs concerning the registration pairs R-EXP (68 ± 88 ml) vs. NR-EXP (69 ± 85 ml) und R-MID (68 ± 86 ml) vs. NR-MID (69 ± 83 ml) (both p > 0.4). However, the MTVs were larger after NR registration during inspiration (R-INS 68 ± 82 vs. NR-INS 78 ± 93 ml; p=0.02). CONCLUSION: The use of nonrigid algorithms may lead to a change in MTV, whose extent is influenced by the breathing manoeuvre on CT. Nonrigid registration methods cannot be recommended for the definition of MTV if the CT scan is performed during inspiration. The choice of registration algorithm has no significant impact on SUVmax.

Prospective study of p-[123I]iodo-L-phenylalanine and SPECT for the evaluation of newly diagnosed cerebral lesions: specific confirmation of glioma.

PURPOSE: The differentiation between gliomas, metastases and gliotic or inflammatory lesions by imaging techniques remains a challenge. Gliomas frequently exhibit increased uptake of radiolabelled amino acids and are thus amenable to PET or SPECT imaging. Recently, p-[123I]iodo-L-phenylalanine (IPA) was validated for the visualization of glioma by SPECT and received orphan drug status. Here we investigated its diagnostic performance for differentiating indeterminate brain lesions. METHODS: This prospective open study included 67 patients with newly diagnosed brain lesions suspicious for glioma (34 without and 33 with contrast enhancement in the MRI scan). Patients received 250 MBq IPA intravenously after overnight fasting. SPECT images at 30 min and 3 h post-injection were iteratively reconstructed and visually interpreted after image fusion with an MRI brain scan (fluid-attenuated inversion recovery sequence or T1-weighted contrast-enhanced image). Findings were correlated with results of stereotactic or open biopsies or serial imaging. RESULTS: Twenty-seven low-grade (2 WHO I, 25 WHO II) and 24 high-grade gliomas (1 WHO III, 23 WHO IV), 3 metastases originating from lung cancer as well as 13 non-neoplastic lesions were proven. All non-neoplastic lesions and all metastases were negative with IPA SPECT. Forty gliomas were true-positive (TP) and 11 false-negative (FN) findings (8 WHO II, 1 WHO III, 2 WHO IV) occurred. There were no false-positive (FP) findings. For the differentiation of primary brain tumours and non-neoplastic lesions, sensitivity and specificity were 78 and 100%. In 34 lesions without contrast enhancement in MRI, IPA SPECT resulted in 17 TP, 8 true-negative, 9 FN and no FP findings (sensitivity 65%, specificity 100%). CONCLUSION: In patients with suspected glioma, IPA SPECT shows a high specificity, but especially in low-grade gliomas FN findings may occur. Due to the high positive predictive value a positive finding allows a suspected glioma to be confirmed.

Risk stratification of solitary pulmonary nodules by means of PET using (18)F-fluorodeoxyglucose and SUV quantification.

PURPOSE: (18)F-fluorodeoxyglucose (FDG) PET is the most accurate imaging modality in characterizing a solitary pulmonary nodule (SPN). Besides visual image interpretation, semiquantitative analysis using standardized uptake values (SUV) is performed to improve diagnostic accuracy. Mostly, an SUV threshold of 2.5 is applied to differentiate between benign and malignant lesions. In this study we analysed the use different SUV thresholds to predict the post-test probability of malignancy for the individual patient considering his pre-test probability. Furthermore, we investigated the prognostic value of SUV in SPN for survival. METHODS: This retrospective study included 140 consecutive patients who underwent FDG PET for evaluation of SPN. Visual interpretation was performed by two readers. For semiquantitative analysis, maximum SUV (SUV(max)) was measured in all SPN. A final diagnosis was obtained by pathological examination or follow-up of more than 2 years. In a nomogram, positive and negative predictive values (PPV and NPV) were plotted against the hypothetical SUV threshold to determine the optimum SUV threshold. Survival was analysed using the Kaplan-Meier method and log-rank test. RESULTS: The prevalence of malignancy was 57%. The FDG uptake in malignant SPNs was higher than in benign SPNs (SUV 9.7 +/- 5.5 vs 2.6 +/- 2.5, p < 0.01). More than 90% of SPNs with an SUV below 2.0 were benign (sensitivity, specificity, NPV of 96, 55 and 92%). The highest diagnostic accuracy was achieved with an SUV of 4.0 (sensitivity, specificity and accuracy of 85%). Visual interpretation achieved corresponding values of 94, 70 and 84%, respectively. In lung cancer higher FDG uptake (SUV(max) >or= 9.5) was associated with shorter survival (median survival 20 months) and low FDG uptake with longer survival (>75 months). CONCLUSION: FDG PET allows assessment of the individual risk for malignancy in SPNs by considering tumoural SUV and pre-test probability. Higher FDG uptake in lung cancer as measured by SUV analysis is a prognostic factor. In patients with low FDG uptake in an SPN and increased risk during surgery omission of diagnostic thoracotomy may be warranted.

Nonrigid versus rigid registration of thoracic 18F-FDG PET and CT in patients with lung cancer: an intraindividual comparison of different breathing maneuvers.

UNLABELLED: In lung cancer, (18)F-FDG PET, CT, and (18)F-FDG PET/CT are used for noninvasive staging and therapy planning. Even with improved image registration techniques-especially in the modern hybrid PET/CT scanners-inaccuracies in the fusion process may occur, leading to errors in image interpretation. The aim of this study was to investigate by an intraindividual analysis whether, in comparison with a rigid algorithm, a nonrigid registration algorithm improves the quality of fusion between (18)F-FDG PET and CT. METHODS: Sixteen patients with histologically proven non-small cell lung cancer underwent a thoracic (18)F-FDG PET acquisition in radiotherapy treatment position and 3 CT acquisitions (expiration, inspiration, and mid breath-hold) on the same day. All scans were registered with rigid and nonrigid procedures, resulting in 6 fused datasets: rigid inspiration, rigid expiration, rigid mid breath-hold, nonrigid inspiration, nonrigid expiration, and nonrigid mid breath-hold. The quality of alignment was assessed by 3 experienced readers at 8 anatomic landmarks: lung apices, aortic arch, heart, spine, sternum, carina, diaphragm, and tumor using an alignment score ranging from 1 (no alignment) to 5 (exact alignment). RESULTS: Nonrigid PET/CT showed better alignment than rigid PET/CT (3.5 +/- 0.7 vs. 3.3 +/- 0.7, P < 0.001). Regarding the breathing maneuver, no difference between nonrigid mid breath-hold and rigid mid breath-hold was observed. In contrast, the alignment quality significantly improved from rigid expiration to nonrigid expiration (3.4 +/- 0.7 vs. 3.6 +/- 0.7, P < 0.001) and from rigid inspiration to nonrigid inspiration (3.1 +/- 0.7 vs. 3.3 +/- 0.7, P < 0.001). With regard to individual landmarks, an improvement in fusion quality through the use of nonrigid registration was obvious at the lung apices, carina, and aortic arch. CONCLUSION: The alignment quality of thoracic (18)F-FDG PET/CT exhibits a marked dependence on the breathing maneuver performed during the CT acquisition, as demonstrated in an intraindividual comparison. Nonrigid registration is a significant improvement over rigid registration if the CT is performed during full inspiration or full expiration. The best fusion results are obtained with the CT performed at mid breath-hold using rigid registration, without an improvement using nonrigid algorithms.

FDG-PET-based radiotherapy planning in lung cancer: optimum breathing protocol and patient positioning--an intraindividual comparison.

PURPOSE: Fluoro-2-deoxy-d-glucose (FDG)-positron emission tomography (PET) and PET/computed tomography (CT) are increasingly used for radiotherapy (RT) planning in patients with non-small-cell lung carcinoma. The planning process often is based on separately acquired FDG-PET/CT and planning CT scans. We compared intraindividual differences between PET acquired in diagnostic (D-PET) and RT treatment position (RT-PET) coregistered with planning CTs acquired using different breathing protocols. METHODS AND MATERIALS: Sixteen patients with non-small-cell lung carcinoma underwent two PET acquisitions (D-PET and RT-PET) and three planning CT acquisitions (expiration [EXP], inspiration [INS], and mid-breath hold [MID]) on the same day. All scans were rigidly coregistered, resulting in six fused data sets: D-INS, D-EXP, D-MID, RT-INS, RT-EXP, and RT-MID. Fusion accuracy was assessed by three readers at eight anatomic landmarks, lung apices, aortic arch, heart, spine, sternum, carina, diaphragm, and tumor, by using an alignment score ranging from 1 (no alignment) to 5 (exact alignment). RESULTS: The RT-PET showed better alignment with any CT than D-PET (p < 0.001). With regard to breathing, RT-MID showed the best mean alignment score (3.7 +/- 1.0), followed by RT-EXP (3.5 +/- 0.9) and RT-INS (3.0 +/- 0.8), with all differences significant (p < 0.001). Comparing alignment scores with regard to anatomic landmarks, the largest deviations were found at the diaphragm, heart, and apices. Overall, there was fair agreement (kappa = 0.48; p < 0.001) among the three readers. CONCLUSIONS: Significantly better fusion of PET and planning CT can be reached with PET acquired in the RT position. The best intraindividual fusion results are obtained with the planning CT performed during mid-breath hold. Our data justify the acquisition of a separate planning PET in RT treatment position if only a diagnostic PET scan is available.

Combining 153Sm-lexidronam and docetaxel for the treatment of patients with hormone-refractory prostate cancer: first experience.

PURPOSE: 153Sm-lexidronam has been used for the palliation of symptoms from painful bone metastases for years, while docetaxel has recently been shown to improve the survival of patients with hormone-refractory prostate cancer (HRPC). The first clinical experience with the combination of both treatment modalities is reported. METHODS: Between 2005 and 2006, 12 patients with muliple bone metastases from HRPC were treated with a single application of 37 MBq/kg body weight 153Sm-lexidronam and 6 weekly infusions of 35 mg/m2 docetaxel. Data on survival, prostate-specific antigen (PSA) response, symptom palliation, toxicity, and scintigraphic follow-up are provided. RESULTS: Mean follow-up was 11.4 (range, 1.1-25.8) months, overall 1-year survival was 48.6%, and median survival was 11.5 months. A PSA response of >50% was documented in 50% of patients. The average pain score (visual analog scale: 1-10) was reduced from 5.1 to 1.4 (p = 0.016) with decrease of > or =2 in 58.3% of patients. The average World Health Organization medication level dropped from 1.6 to 1.1 (p = 0.5). Overall toxicity was moderate, but 1 patient died due to neutropenic sepsis. CONCLUSIONS: Our analysis demonstrates feasibility and therapeutic potential for the combination treatment and merits prospective investigation. Further studies will be planned with respect to the potentially synergistic hematologic toxicity of bone-seeking radiopharmaceuticals and chemotherapy.

Low-dose MDCT for surveillance of patients with severe homogeneous emphysema after bronchoscopic airway bypass.

OBJECTIVE: The purpose of this study was to evaluate the usefulness of low-dose MDCT for radiologic monitoring of patients who have undergone placement of bronchial stents for airway bypass. SUBJECTS AND METHODS: In a prospective study, seven patients underwent MDCT according to a low-dose protocol (40 mAs, 120 kVp) before and after stent placement. The positions of the stents in the segmental bronchi were analyzed and compared with the bronchoscopic findings, which were reference standard. Patency versus lack of patency of stents was classified with five levels of confidence, and a definitive diagnosis was assigned to each stent. Prediction of stent dislodgment, follow-up findings, and complications occurring during the observation period were recorded. Consensus reading was performed by two radiologists. Statistical analysis was conducted by receiver operating characteristic analysis or four-field table. RESULTS: Seven patients underwent implantation of 37 stents (mean, 5 +/- 2 [SD] stents per patient; range, 2-8 stents). The area under the curve for differentiating patent from occluded stents was 0.995 with resulting sensitivity and specificity of 86.5% and 98.1%. The correct diagnosis of patency was established with MDCT for all but one stent (sensitivity, 94.7%; specificity, 100%). Sensitivity and specificity for prediction of dislodgment were 80% and 91%. Five stents were not identified during inspection bronchoscopy but were found in a regular position at MDCT. Three instances of minor bleeding and one of pneumothorax resolved spontaneously. The mean effective dose of the scan was 1.3 +/- 0.6 mSv. CONCLUSION: Low-dose MDCT is feasible for radiologic monitoring after airway bypass procedure.

Extraosseous manifestation of multiple myeloma with unusual appearance in computed tomography--case report.

Extramedullary Localizations at diagnosis or during the course of multiple myeloma are rare. We report on a 70 year old patient, presenting multiple hypoechoic liver lesions during an ultrasound examination. The following contrast-enhanced computed tomography demonstrated hypodense liver Lesions with slight contrast enhancement and hyperdense polypoid masses in the wall of the gall bladder as well as a small pericostal tumor. A punch biopsy of the liver and immunohistochemical studies confirmed the diagnosis of extramedullary multiple myeloma. In a follow-up CT five weeks later the liver lesions and the pericostal tumor clearly showed progress, the masses in the gall bladder had developed into a concentric wall-thickening. Additionally, polypoid contrast-enhancing masses in the gastric wall became apparent as well as a hypodense lesion in the spleen. Radiologists should be aware that multiple myeloma can on rare occasions present as hypodense nodules in the liver or new masses in other organs in CT. Because of the morphologic similarity to metastatic disease, a biopsy may be necessary for definitive diagnosis.