293 research outputs found
The surgical treatment of pituitary adenomas in the eighth decade
BACKGROUND The surgical treatment of pituitary adenomas in elderly patients (i.e., over 70 years of age) is a special problem because of the increased rate of perioperative complications and the reduced tolerance of postoperative fluid and electrolyte imbalance. Therefore, the unquestionable progress in the pharmacological and radiotherapy may not allow these patients the option of radical surgical treatment, We report our experience with the transsphenoidal procedure for pituitary adenomas in aged patients in an attempt to contribute to a better definition of the actual role of surgery.
METHODS Transsphenoidal surgery was performed in 11 patients over 70 years of age affected by various histological types of pituitary micro- and macroadenomas, ranging from Hardy Grade I through IIIc, Special care was dedicated to the postoperative treatment, in particular to water and electrolyte balances, and to the immediate treatment of any pathological variation of these parameters.
RESULTS We had no mortality and no postoperative adjunctive morbidity, All the patients recovered well from the operation with an average hospital stay of 20 days. The tumor removal was complete in six cases and partial in the remaining five. With an average follow-up of 2 years, we did observe only one case of symptomatic recurrence of the disease.
CONCLUSIONS Transsphenoidal surgery in the elderly is feasible and quite safe in the hands of an experienced team, if special care is devoted to the preoperative selection of patients and to the postoperative treatment of fluid and electrolyte imbalanc
Spinal hydatidosis relapse: a case report
Human cystic echinococcosis (CE) is a zoonosis caused by the larval stage of the Echinococcus granulosus and the most common sites affected are the liver and lung in approximately 80–90% of cases. The hydatid bone represents the 0.5–2.5% of all cases and localization cord is present about 50% of the time. This benign and commonly asymptomatic disease may simulate an aggressive malignancy because of osseous destruction and aggressive extension. We report a case of a 42-year-old male patient, presented with an unusual spinal hydatidosis relapse, related to anthelmintic drug therapy withdrawal after 10-year treatment. The man had previous excision of chest and hepatic hydatid cysts (resp., 10 and 3 years ago) and after primary mediastinal and spinal involvement (3 years ago) he was lost to follow-up and discontinued drug therapy. The patient underwent surgery and the postoperative histopathology confirmed the diagnosis. The patient recovered with no complications. Despite significant progress in diagnostic imaging, pharmacological and surgical therapy, spinal CE remains associated with high morbidity
Revalidation of PET/computed tomography criteria (Hopkins criteria) for the assessment of therapeutic response in lung cancer patients: inter-reader reliability, accuracy and survival outcomes
BACKGROUND/AIM: Systematic reporting using qualitative evaluation of PET/computed tomography (CT) results has been demonstrated to be very accurate and reproducible in posttherapy assessment of lung cancer (so-called Hopkins criteria). Our aim was to test, in a different cohort of patients, the Hopkins criteria for assessment of therapeutic response in lung cancer and to compare the results with those obtained using a semi-quantitative evaluation of uptake. METHODS: This is a retrospective study. A total of 85 patients with known lung cancer who underwent fluorine-18 fluorodeoxyglucose PET/CT assessment within 24 weeks (mean 7.9 weeks) of completion of treatment were included. Treatments included surgical resection, chemotherapy, radiation therapy, immunotherapy or combinations thereof. PET/CT interpretation was done by two nuclear medicine physicians, and discrepancies were resolved by a third interpreter. Studies were scored both according to the Hopkins criteria using qualitative assessment of tracer uptake for the primary tumour, locoregional disease in the mediastinum and distant metastatic sites and by applying the same five-point score using a semi-quantitative measure, maximum standardized uptake value. Overall scores of 1, 2 and 3 were considered negative for residual disease, while scores of 4 and 5 were considered positive. Patients were followed up for a median of 18.5 months (range 2-139 months). Kaplan-Meier plots with a Mantel-Cox log-rank test were performed, considering death as the endpoint. Inter-reader variability was assessed using percent agreement and kappa statistics. RESULTS: The Cohen κ coefficient analysis showed substantial agreement between the two interpreters on the five-point Hopkins criteria scoring, with a κ of 0.73. There was almost perfect agreement between the interpreters with respect to classification as positive or negative according to the Hopkins criteria, with a κ of 0.89. The sensitivity, specificity, positive predictive value, negative predictive value and accuracy of the Hopkins criteria were 88.5% [95% confidence interval (CI) 80.6-96.5%), 79.2% (95% CI 63.2-95.1%), 91.5% (95% CI 84.4-98.6%), 73.1% (95% CI 61.8-84.4%) and 85.9% (95% CI 78.5-93.3%), respectively. There was almost perfect agreement between the qualitative and semi-quantitative scoring with a κ of 0.87, with sensitivity, specificity, positive predictive value, negative predictive value and accuracy of the semi-quantitative Hopkin's criteria of 86.9% (95% CI 78.4-95.4%), 79.2% (95% CI 62.9-95.4%), 91.4% (95% CI 84.2-98.6%), 70.4% (95% CI 58.6-82.1%) and 84.7% (95% CI 80.8-92.4%), respectively. CONCLUSION: The use of Hopkins criteria for posttherapy assessment in patients with lung cancer represents an easy and reproducible method with substantial to almost perfect interobserver agreement and high positive predictive value and accuracy; moreover, it is easily understood by referring physicians. Additionally, there was no significant difference when applying a semi-quantitative measure to the same five-point score
Clinical impact of respiratory motion correction in simultaneous PET/MR, using a joint PET/MR predictive motion model
In Positron Emission Tomography (PET) imaging, patient motion due to respiration can lead to artefacts and blurring, in addition to quantification errors. The integration of PET imaging with Magnetic Resonance (MR) imaging in PET/MR scanners provides spatially aligned complementary clinical information, and allows the use of high spatial resolution and high contrast MR images to monitor and correct motion-corrupted PET data. We validate our PET respiratory motion correction methodology based on a joint PET-MR motion model, on a patient cohort, showing it can improve lesion detectability and quantitation, and reduce image artefacts. Methods: We apply our motion correction methodology on 42 clinical PET-MR patient datasets, using multiple tracers and multiple organ locations, containing 162 PET-avid lesions. Quantitative changes are calculated using Standardised Uptake Value (SUV) changes in avid lesions. Lesion detectability changes are explored with a study where two radiologists identify lesions or \u27hot spots\u27, providing confidence levels, in uncorrected and motion-corrected images. Results: Mean increases of 12.4% for SUV_peak and 17.6% for SUV_max following motion correction were found. In the detectability study, an increase in confidence scores for detecting avid lesions is shown, with a mean score of 2.67 rising to 3.01 (out of 4) after motion correction, and a detection rate of 74% rising to 84%. Of 162 confirmed lesions, 49 lesions showed an increase in all three metrics SUV_peak, SUV_max and combined reader confidence scores, whilst only two lesions showed a decrease. We also present a number of clinical case studies, demonstrating the effect respiratory motion correction of PET data can have on patient management, with increased numbers of lesions detected, improved lesion sharpness and localisation, as well as reduced attenuation-based artefacts. Conclusion: We demonstrate significant improvements in quantification and detection of PET-avid lesions, with specific case study examples showing where motion correction has the potential to have an effect on patient diagnosis or care
3-T MRI and clinical validation of ultrasound-guided transperineal laser ablation of benign prostatic hyperplasia
Background: Transperineal laser ablation (TPLA) of the prostate is a novel, mini-invasive option for men with lower urinary tract symptoms (LUTS) due to benign prostate hyperplasia (BPH). Our aim was to assess the impact of ultrasound-guided TPLA regarding urodynamic improvement and sexual function, monitoring clinical data, postprocedural complications and imaging findings at 3-T multiparametric magnetic resonance imaging. Methods: Forty-four patients aged ≥ 50 affected with moderate to severe LUTS (International Prostate Symptoms score ≥ 12) due to benign prostatic obstruction and refractoriness, intolerance or poor compliance to medical therapies underwent US-guided TPLA between May 2018 and February 2020. Clinical measurements included PSA, uroflowmetry, sexual function assessment (using the International Index of Erectile Function and Male Sexual Health Questionnaire-Ejaculatory Dysfunction short form) and quality of life questionnaire. Adverse events were evaluated using the Clavien-Dindo scale. Volume changes were measured by MRI and automatic segmentation software during 1-year follow-up. Registration: NCT04044573 – May 5th, 2018, https://www.clinicaltrials.gov Results: MRI assessed the changes over time with a 53% mean reduction of adenoma volume and 71% of the ablated area, associated with clinical and functional improvement and resolution of LUTS in all cases. Five of 44 patients (11.3%) had urinary blockage due to clots and required re-catheterisation for 2 weeks. The overall adverse event rate was 7%. Conclusion: US-guided TPLA performed as a safe, manageable and effective treatment for LUTS. It could be considered an alternative effective mini-invasive procedure to standard treatments for BPH in the outpatient setting
PET/MRI attenuation estimation in the lung: A review of past, present, and potential techniques
Positron emission tomography/magnetic resonance imaging (PET/MRI) potentially offers several advantages over positron emission tomography/computed tomography (PET/CT), for example, no CT radiation dose and soft tissue images from MR acquired at the same time as the PET. However, obtaining accurate linear attenuation correction (LAC) factors for the lung remains difficult in PET/MRI. LACs depend on electron density and in the lung, these vary significantly both within an individual and from person to person. Current commercial practice is to use a single-valued population-based lung LAC, and better estimation is needed to improve quantification. Given the under-appreciation of lung attenuation estimation as an issue, the inaccuracy of PET quantification due to the use of single-valued lung LACs, the unique challenges of lung estimation, and the emerging status of PET/MRI scanners in lung disease, a review is timely. This paper highlights past and present methods, categorizing them into segmentation, atlas/mapping, and emission-based schemes. Potential strategies for future developments are also presented
Non-small-cell lung cancer resectability: diagnostic value of PET/MR.
Purpose
To assess the diagnostic performance of PET/MR in patients with non-small-cell lung cancer.
Methods
Fifty consecutive consenting patients who underwent routine 18F-FDG PET/CT for potentially radically treatable lung cancer following a staging CT scan were recruited for PET/MR imaging on the same day. Two experienced readers, unaware of the results with the other modalities, interpreted the PET/MR images independently. Discordances were resolved in consensus. PET/MR TNM staging was compared to surgical staging from thoracotomy as the reference standard in 33 patients. In the remaining 17 nonsurgical patients, TNM was determined based on histology from biopsy, imaging results (CT and PET/CT) and follow-up. ROC curve analysis was used to assess accuracy, sensitivity and specificity of the PET/MR in assessing the surgical resectability of primary tumour. The kappa statistic was used to assess interobserver agreement in the PET/MR TNM staging. Two different readers, without knowledge of the PET/MR findings, subsequently separately reviewed the PET/CT images for TNM staging. The generalized kappa statistic was used to determine intermodality agreement between PET/CT and PET/MR for TNM staging.
Results
ROC curve analysis showed that PET/MR had a specificity of 92.3 % and a sensitivity of 97.3 % in the determination of resectability with an AUC of 0.95. Interobserver agreement in PET/MR reading ranged from substantial to perfect between the two readers (Cohen’s kappa 0.646 – 1) for T stage, N stage and M stage. Intermodality agreement between PET/CT and PET/MR ranged from substantial to almost perfect for T stage, N stage and M stage (Cohen’s kappa 0.627 – 0.823).
Conclusion
In lung cancer patients PET/MR appears to be a robust technique for preoperative staging
Evolution of 18F-FDG-PET/CT findings in patients following COVID-19 pneumonia: An Initial Investigation
Background: The evolution of pulmonary 18F-FDG uptake is unknown in patients with pneumonia due to SARS-CoV-2 (COVID-19 pneumonia) and in those with persistent respiratory symptoms post-COVID-19 termed Post-COVID-19 Lung-Disease (PCLD). The aim of this study was to assess the temporal evolution of pulmonary 18F-FDG uptake and identify a potential role for the use of 18F-FDG-PET/CT imaging in the management of these patients. Methods: Clinical data and CT imaging of all patients that underwent 18F-FDG-PET/CT imaging at UCLH, Lon-don during the UK pandemic were reviewed to find evidence of active or recovered SARS-CoV-2 infection. Results of PCR tests were used where available. Patients were divided in to acute (early and late) COVID-19 pneumonia, PCLD and asymptomatic recovery. 18F-FDG uptake in the lungs was measured as a target-to-background ratio (SUVmax/SUVmin) TBRlung which was compared to temporal-stage and plasma CRP. Results: There were 50 patients in total (median 61y, range 18-87y, 32-male): 23 incidental acute COVID-19 pneumonia cases identified retrospectively (8 Early, 15 Late), 9 asymptomatic recovered patients, and 18 cases performed for PCLD. In acute COVID-19 patients <3 weeks since disease onset TBRlung was strongly correlated with time since disease onset (rs=0.81, p<0.001)
Clinical Impact of Respiratory Motion Correction in Simultaneous PET/MR with a Joint PET/MR Predictive Motion Model
In Positron Emission Tomography (PET) imaging, patient motion due to respiration can lead to artefacts and blurring, in addition to quantification errors. The integration of PET imaging with Magnetic Resonance (MR) imaging in PET/MR scanners provides spatially aligned complementary clinical information, and allows the use of high spatial resolution and high contrast MR images to monitor and correct motion-corrupted PET data. We validate our PET respiratory motion correction methodology based on a joint PET-MR motion model, on a patient cohort, showing it can improve lesion detectability and quantitation, and reduce image artefacts. METHODS: We apply our motion correction methodology on 42 clinical PET-MR patient datasets, using multiple tracers and multiple organ locations, containing 162 PET-avid lesions. Quantitative changes are calculated using Standardised Uptake Value (SUV) changes in avid lesions. Lesion detectability changes are explored with a study where two radiologists identify lesions or 'hot spots', providing confidence levels, in uncorrected and motion-corrected images. RESULTS: Mean increases of 12.4% for SUV_peak and 17.6% for SUV_max following motion correction were found. In the detectability study, an increase in confidence scores for detecting avid lesions is shown, with a mean score of 2.67 rising to 3.01 (out of 4) after motion correction, and a detection rate of 74% rising to 84%. Of 162 confirmed lesions, 49 lesions showed an increase in all three metrics SUV_peak, SUV_max and combined reader confidence scores, whilst only two lesions showed a decrease. We also present a number of clinical case studies, demonstrating the effect respiratory motion correction of PET data can have on patient management, with increased numbers of lesions detected, improved lesion sharpness and localisation, as well as reduced attenuation-based artefacts. CONCLUSION: We demonstrate significant improvements in quantification and detection of PET-avid lesions, with specific case study examples showing where motion correction has the potential to have an effect on patient diagnosis or care
Biosynthesis of HLA-C heavy chains in melanoma cells with multiple defects in the expression of HLA-A, -B, -C molecules
Recent investigations have shown that malignant transformation may down-regulate the expression of class I HLA molecules, beta(2)-microglobulin (beta(2)m) and members of the antigen-processing machinery. In the present study, we HLA-genotyped and identified at a biochemical level the three (HLA-A25, -B8, -Cw7) class I alleles expressed by the previously described [D'Urso CM et al (1992) J Clin Invest 87: 284-292] beta(2)m-defective human melanoma FO-1 cell line and tested their ability to interact with calnexin, calreticulin and the TAP (transporter associated with antigen processing) complex. Ail these alleles were found to bind calnexin, but not calreticulin or the poorly expressed TAP complex, both in parental and beta(2)m-transfected FO-1 cells, demonstrating a complex defect of class I expression in FO-1 cells. In these conditions, Cw7 heavy chains interacted with calnexin more strongly than A25 and B8, and preferentially accumulated in the endoplasmic reticulum, in both a calnexin-associated and a calnexin-free form. In addition, they could be transported to the cell surface at low levels even in the absence of beta(2)m, without undergoing terminal glycosylation. These results establish a parallel between HLA-C and the murine D-b and L-d molecules which have been found to be surface expressed and functional in beta(2)m-defective cells. They also demonstrate distinctive features of HLA-C molecules. We propose that the accumulation of several assembly intermediates of HLA-C might favour the binding of peptide antigens not readily bound by HLA-A and -B molecules in neoplastic cells with suboptimal class I expression
- …