Pleural small cell lung cancer masquerading as malignant mesothelioma: A case report.

Nodular soft tissue pleural thickening on imaging is highly suggestive of malignancy, of which pleural malignant mesothelioma and metastatic disease are differentials. We present the case of a 71-year-old male who presented with acute worsening of shortness of breath associated with a recurrent left pleural effusion post-pleurocentesis. He was an ex-smoker with previous asbestos exposure. Computed tomography performed demonstrated left-sided pleural thickening in the hemithorax and hemidiaphragm with complex pleural effusion. 18F-2-deoxy-d-glucose whole body PET scan revealed extensive uptake throughout the left hemithorax in multiple pleural masses. The imaging findings and clinical case were typical of malignant mesothelioma. However, histopathology results revealed small cell lung cancer. We need to be cognisant of this atypical presentation of a common disease entity. Even when all clinical and imaging findings point towards a certain diagnosis, histopathological assessment cannot be ignored.

Outcomes of incidental findings on multi-detector computed tomography for transcatheter aortic valve implantation assessment: A single-centre study and review of the literature.

INTRODUCTION: Patients with severe aortic stenosis (AS) require multi-detector computed tomography (MDCT) when considered for transcatheter aortic valve implantation (TAVI). Incidental findings on MDCT are common given the age group and region imaged. Our aim was to evaluate the frequency and outcome of incidental findings (IF) identified on MDCT and the impact on survival. METHODS: This single-centre analysis retrospectively reviewed severe AS patients who underwent MDCT during TAVI workup. MDCT reports were reviewed for any IF and defined into three categories: IF of no relevant clinical significance (IF-NoCS), IF of non-immediate clinical significance (IF-NICS) and IF of immediate clinical significance (IF-ICS). Demographics, follow-up of IF and survival were calculated from MDCT date. RESULTS: Two hundred and sixty-five patients underwent MDCT for TAVI suitability (mean age 83 ± 6 years, 52% male). The majority proceeded to TAVI (65%). Renal lesions (25%) and lung nodules (18%) were the most common IF. Fifty-nine patients (22%) had IF-NICS; 39% (23/59) were benign, 59% were not further investigated and one patient had suspected lung cancer. Six patients (2.3%) had IF-ICS and all were diagnosed with lung cancer. During a median follow-up of 272 days, there was no survival difference between patients with IF-ICS or IF-NICS versus patients without IF or IF-NoCS in the overall cohort (P = 0.44) or in TAVI patients (P = 0.88). CONCLUSION: Incidental findings on MDCT are common with one-quarter having IF-ICS or IF-NCIS. Most patients with IF-NICS did not undergo further investigation. Standardized reporting of MDCT may assist in clarifying the need for further investigation which will in turn influence decision and timing to proceed with TAVI.

Prevalence of non 18 F-fluorodeoxyglucose-avid incidental findings of clinical significance on whole body positron emission tomography/computed tomography: A review of 500 consecutive cases.

INTRODUCTION: The prevalence of incidental 18 F-fluorodeoxyglucose (FDG)-avid findings on positron emission tomography-computed tomography (PET/CT) has been extensively described. Few studies, however, have assessed the prevalence and significance of non-FDG-avid findings; pathology that is identified on review of the low-dose, non-contrast CT. The aim of this study was to determine the overall prevalence of non FDG-avid incidental findings on PET/CT and the prevalence of 'clinically significant' non FDG-avid pathology. METHODS: Five hundred consecutive whole body PET/CT studies performed in 2016 at a university affiliated tertiary hospital were retrospectively reviewed by two radiologists experienced in reporting PET/CT. Findings were categorized according to potential clinical relevance, and a targeted follow-up of clinically significant incidental findings was performed. RESULTS: Incidental findings were encountered in 463 of 500 (92.6%) patients. In 226 patients, these findings had been detected on previous imaging studies, with unknown incidental findings present in 237 of 500 (47.4%) patients. 113 of 500 (22.6%) patients had non-avid incidental findings of potentially major clinical significance, and in 35 patients (7.0%) these findings were considered previously unknown. The most common non-avid findings of potentially major significance were pulmonary nodules (6 mm or larger), moderate or large size pleural effusions, and vascular aneurysms. Unknown incidental findings of potentially major clinical significance were significantly higher in patients imaged for melanoma staging (P= 0.004). CONCLUSION: The prevalence of incidental findings of clinical significance that do not accumulate FDG in PET/CT is not insignificant. Routine systematic review of the low-dose CT is required to avoid missing potentially clinically important findings, in particular pleural effusions, vascular aneurysms and metastatic pulmonary nodules.

Intraventricular CNS lesions: A pictorial essay.

Intraventricular lesions of the central nervous system (CNS) can present a diagnostic challenge due to a range of differential diagnoses and radiological appearances. Both CT and MRI imaging findings, in combination with location and patient's age, can help limit the differentials. This pictorial essay presents the salient radiological features, location and demographics of the more common intraventricular lesions of the brain.

Hybrid proximal surgery plus adjunctive retrograde endovascular repair in acute DeBakey type I dissection: superior outcomes to conventional surgical repair.

OBJECTIVE: The present study compared the outcomes between conventional surgery and the hybrid approach of proximal surgery with adjunctive retrograde descending aortic endografting plus distal bare metal stenting in acute DeBakey type I dissection. METHODS: From 2003 to 2011, 61 patients underwent surgical management for acute type A aortic dissection at our institution. Of these, 37 were DeBakey type I dissections: 18 patients (group 1) received conventional surgical repair alone, and 19 (group 2) underwent conventional hybrid surgery with adjunctive retrograde descending aortic stent grafting plus distal bare metal stenting. RESULTS: The patients' baseline characteristics were comparable, including the incidence of preoperative malperfusion syndromes (P = .23). The intraoperative and postoperative characteristics were similar, except 4 (22%) patients in group 1 (vs 0 in group 2) had ongoing malperfusion postoperatively (P = .04). Overall, hospital mortality was 11% (n = 2) for group 1 versus 5% (n = 1) for group 2. At a mean follow-up of 50 months, 4 (25%) subjects in group 1 required secondary thoracoabdominal aortic reintervention versus none in group 2 (P = .03). CONCLUSIONS: The use of adjunctive retrograde descending aortic endografting plus distal bare metal stenting during acute DeBakey type 1 dissection repair is a feasible method to enhance thoracoabdominal remodeling. This hybrid strategy improves perioperative outcomes and decreases late distal aortic complications compared with conventional surgical repair for acute DeBakey type I dissection. A prospective, multicenter study is warranted to definitively assess this promising new treatment paradigm.

Combined proximal stent grafting plus distal bare metal stenting for management of aortic dissection: Superior to standard endovascular repair?

OBJECTIVES: The present study compared the outcomes between combined proximal descending aortic endografting plus distal bare metal stenting and conventional proximal descending aortic stent-graft repair in patients with type A and type B aortic dissection. METHODS: From January 2003 to December 2010, 63 patients underwent endovascular treatment for acute (type A, 24; type B, 21) and chronic (type B, 18) aortic dissection. Of these, 40 patients underwent proximal descending aortic endografting plus distal bare metal stenting (group 1), and 23 underwent proximal descending stent-graft repair alone (group 2). All patients with type A dissection underwent open surgical intervention plus adjunctive retrograde endovascular repair. RESULTS: The patients were comparable for baseline characteristics and treatment indicators, but more group 1 patients were active smokers (P = .03). The intraoperative characteristics were also similar, although 4 patients, all in group 2, developed malperfusion syndrome postoperatively (P = .02). The overall hospital mortality was 6%. At a mean follow-up of 49 months, 9 group 2 patients (43%) required unplanned secondary intervention compared with 4 in group 1 (11%; P = .007). Reintervention for thoracoabdominal aortic aneurysm or visceral ischemia was performed in 4 patients (19%) from group 2 (P = .03). Late aortic-related deaths occurred in 1 (5 %) and 2 (5%) patients in groups 1 and 2, respectively. CONCLUSIONS: Combined proximal descending aortic endografting plus distal bare metal stenting for aortic dissection provides favorable short-term outcomes and decreases late distal aortic complications compared with conventional endovascular repair. These results support a more widespread application of this approach. A prospective, randomized trial is needed before definite conclusions can be made.

Magnetic resonance features of primary central nervous system lymphoma in the immunocompetent patient: a pictorial essay.

Primary central nervous system lymphoma (PCNSL) is an uncommon but important variant of non-Hodgkin lymphoma and represents up to 6% of all primary central nervous system (CNS) malignancies. Recognition of this entity by radiologist on MRI may avoid unnecessary neurosurgical resection and redirect to biopsy. The pretreatment MRI of patients with biopsy proven PCNSL from the last 5 years at our institution was reviewed. Selected examples were used to construct a pictorial essay to illustrate some of the typical and atypical MR features of PCNSL. MRI of other CNS conditions with imaging similarities to PCNSL was included to demonstrate possible mimics. The typical features of PCNSL lymphoma are intra-axial homogenous single or multiple contrast enhancing lesions, with marked surrounding oedema and restricted diffusion, usually contacting a cerebrospinal fluid (CSF) surface. Necrosis, peripheral enhancement, haemorrhage or calcification are unusual and other diagnoses should be considered if any of these features are present. Potential mimics include high grade glioma, infarcts, metastatic disease, demyelination, abscess and secondary lymphoma. Careful assessment of the MR features and correlation with the clinical findings should enable the radiologists to raise the possibility of PCNSL and minimise the risk of unnecessary resection.

Combined proximal endografting with distal bare-metal stenting for management of aortic dissection.

BACKGROUND: Established endovascular treatments for aortic dissection often result in incomplete aortic repair, potentially leading to late complications involving the distal aorta. To address the problems of incomplete true lumen reconstitution and late aneurysmal change, we report the midterm results of combined proximal endografting with distal true lumen bare-metal stenting (STABLE: Staged Total Aortic and Branch vesseL Endovascular reconstruction) in Stanford type A and B aortic dissection. METHODS: Between January 2003 and January 2010, 31 patients underwent staged total aortic and branch vessel endovascular reconstruction for management of acute (type A, 13; type B, 11) and chronic (type B, 7) aortic dissection. Proximal endografting was combined with bare-metal Z stent implantation in the distal true lumen. Patients with type A dissection underwent adjunctive treatment at operation. Computed tomography angiography was performed at baseline, 1 year, and annually thereafter to assess aortic remodelling. RESULTS: Primary technical success was 97%. Thirty-day rates of death, stroke, and permanent paraplegia/paresis were 3% (n=1), 0%, and 0%, respectively. Mean follow-up was 57.3 months (range, 5 to 100 months). Overall survival was 60% at 100 months. Aortic-specific survival was 93%. Four patients (13%) underwent device-related reintervention. One (3%) late aortic-related death occurred. Thoracic (p=0.64) and abdominal (p=0.14) aortic dimensions were stable. The true lumen index increased significantly at follow-up. CONCLUSIONS: Staged total aortic and branch vessel endovascular reconstruction is a feasible ancillary endovascular technique to address the problems of distal true lumen collapse, incomplete aortic remodelling, and late aneurysm formation in aortic dissection.

Positron emission tomography with selected mediastinoscopy compared to routine mediastinoscopy offers cost and clinical outcome benefits for pre-operative staging of non-small cell lung cancer.

PURPOSE: (18)F-fluorodeoxyglucose positron emission tomography (FDG-PET) imaging is an important staging procedure in patients with non-small cell lung cancer (NSCLC). We aimed to demonstrate, through a decision tree model and the incorporation of real costs of each component, that routine FDG-PET imaging as a prelude to curative surgery will reduce requirements for routine mediastinoscopy and overall hospital costs. METHODS: A decision tree model comparing routine whole-body FDG-PET imaging to routine staging mediastinoscopy was used, with baseline variables of sensitivity, specificity and prevalence of non-operable and metastatic disease obtained from institutional data and a literature review. Costings for hospital admissions for mediastinoscopy and thoracotomy of actual patients with NSCLC were determined. The overall and average cost of managing patients was then calculated over a range of FDG-PET costs to derive projected cost savings to the community. RESULTS: The prevalence of histologically proven mediastinal involvement in patients with NSCLC presenting for surgical assessment at our institution is 20%, and the prevalence of distant metastatic disease is 6%. Based on literature review, the pooled sensitivity and specificity of FDG-PET for detection of mediastinal spread are 84% and 89% respectively, and for mediastinoscopy, 81% and 100%. The average cost of mediastinoscopy for NSCLC in our institution is 4,160 AUD, while that of thoracotomy is 15,642 AUD. The cost of an FDG-PET scan is estimated to be 1,500 AUD. Using these figures and the decision tree model, the average cost saving is 2,128 AUDper patient. CONCLUSION: Routine FDG-PET scanning with selective mediastinoscopy will save 2,128 AUD per patient and will potentially reduce inappropriate surgery. These cost savings remain robust over a wide range of disease prevalence and FDG-PET costs.