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1.
Singapore Med J ; 2021 10 11.
Artigo em Inglês | MEDLINE | ID: mdl-34628803

RESUMO

INTRODUCTION: Ultrasound (US) is current standard of care for imaging surveillance in patients at risk for hepatocellular carcinoma (HCC). Magnetic resonance imaging (MRI) has been explored as an alternative, given the higher sensitivity of MRI, although this comes at a higher cost. We performed a cost-effective analysis comparing US and a dual-sequence non-contrast MRI (NCEMRI) for HCC surveillance, in the local setting. METHODS: Cost-effectiveness analysis of no surveillance, US surveillance and NCEMRI surveillance was performed using Markov modelling and microsimulation. At-risk patient cohort was simulated and followed-up for 40 years to estimate their disease status, direct medical costs, and effectiveness. Quality-adjusted life years (QALYs) and incremental cost effectiveness ratio were calculated. RESULTS: 482,000 patients with an average age of 40 years were simulated and followed up for 40 years. The average total costs and QALYs for the three scenarios - no surveillance, US surveillance and NCEMRI surveillance were S$1,193/7.460 QALYs; S$8,099/11.195 QALYs; S$9,720/11.366 QALYs, respectively. CONCLUSION: Despite NCEMRI having a superior diagnostic accuracy, it is a less cost-effective strategy than US for HCC surveillance in the general at-risk population. Future local cost-effectiveness analyses should include stratifying surveillance methods with a variety of imaging techniques (US, NCEMRI, CEMRI) based on patients' risk profiles.

2.
Br J Radiol ; : 20210509, 2021 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-34520694

RESUMO

OBJECTIVES: To perform a systematic review and meta-analysis comparing diagnostic performance and inter reader agreement between PI-RADS v. 2.1 and PI-RADS v. 2 in the detection of clinically significant prostate cancer (csPCa). METHODS: A systematic review was performed, searching the major biomedical databases (Medline, Embase, Scopus), using the keywords "PIRADS 2.1" or "PI RADS 2.1" or "PI-RADS 2.1". Studies reporting on head-to-head diagnostic comparison between PI-RADS v. 2.1 and v. 2 were included. Pooled sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) were compared between PI-RADS v. 2.1 and v. 2. Summary receiver operator characteristic graphs were plotted. Analysis was performed for whole gland, and pre-planned subgroup analysis was performed by tumour location (whole gland vs transition zone (TZ)), high b-value DWI (b-value ≥1400 s/mm2), and reader experience (<5 years vs ≥5 years with prostate MRI interpretation). Inter-reader agreement and pooled rates of csPCa for PI-RADS 1-3 lesions were compared between PI-RADS v. 2.1 and v. 2. Study quality was assessed using the Quality Assessment of Diagnostic Accuracy Studies tool v. 2 (QUADAS-2). RESULTS: Eight studies (1836 patients, 1921 lesions) were included. Pooled specificity for PI-RADS v. 2.1 was significantly lower than PI-RADS v. 2 for whole gland (0.62 vs 0.66, p = 0.02). Pooled sensitivities, PPVs and NPVs were not significantly different (p = 0.17, 0.31, 0.41). Pooled specificity for PI-RADS v. 2.1 was significantly lower than PI-RADS v. 2 for TZ only (0.67 vs 0.72, p = 0.01). Pooled sensitivities, PPVs and NPVs were not significantly different (p = 0.06, 0.36, 0.17). Amongst studies utilising diffusion-weighted imaging with highest b-value of ≥1400 s/mm2, pooled sensitivities, specificities, PPVs and NPVs were not significantly different (p = 0.52, 0.4, 0.5, 0.47). There were no significant differences in pooled sensitivities, specificities, PPVs and NPVs between PI-RADS v. 2.1 and PI-RADS v. 2 for less-experienced readers (p = 0.65, 0.37, 0.65, 0.81) and for more experienced readers (p = 0.57, 0.90, 0.91, 0.65). For PI-RADS v. 2.1 alone, there were no significant differences in pooled sensitivity, specificity, PPV and NPV between less and more experienced readers (p = 0.38, 0.70, 1, 0.48). Inter-reader agreement was moderate to substantial for both PI-RADS v. 2.1 and v. 2. There were no significant differences between pooled csPCa rates between PI-RADS v. 2.1 and v. 2 for PI-RADS 1-2 lesions (6.6% vs 7.3%, p = 0.53), or PI-RADS 3 lesions (24.1% vs 26.8%, p = 0.28). CONCLUSIONS: Diagnostic performance and inter-reader agreement for PI-RADS v. 2.1 is comparable to PI-RADS v. 2, however the significantly lower specificity of PI-RADS v. 2.1 may result in increased number of unnecessary biopsies. ADVANCES IN KNOWLEDGE: 1. Compared to PI-RADS v. 2, PI-RADS v. 2.1 has a non-significantly higher sensitivity but a significantly lower specificity for detection of clinically significant prostate cancer.2. PI-RADS v. 2.1 could potentially result in considerable increase in number of negative targeted biopsy rates for PI-RADS 3 lesions, which could have been potentially avoided.

4.
Korean J Radiol ; 22(7): 1087-1099, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33856136

RESUMO

MRI has become important for the detection of prostate cancer. MRI-guided biopsy is superior to conventional systematic biopsy in patients suspected with prostate cancer. MRI is also increasingly used for monitoring patients with low-risk prostate cancer during active surveillance. It improves patient selection for active surveillance at diagnosis, although its role during follow-up is unclear. We aim to review existing evidence and propose a practical approach for incorporating MRI into active surveillance protocols.


Assuntos
Imagem por Ressonância Magnética Intervencionista , Imageamento por Ressonância Magnética Multiparamétrica , Neoplasias da Próstata , Humanos , Biópsia Guiada por Imagem , Imageamento por Ressonância Magnética , Masculino , Neoplasias da Próstata/diagnóstico por imagem , Conduta Expectante
5.
Global Spine J ; : 2192568221994798, 2021 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-33648366

RESUMO

STUDY DESIGN: Retrospective cohort study. OBJECTIVE: To evaluate the outcomes of conventionally-fractionated external beam radiation therapy (cEBRT) in the treatment of prostate cancer spinal metastases (PCSM). METHODS: Patients who received palliative cEBRT for PCSM in our institution between 2008 and 2018 were included. Our outcomes were local progression-free survival (LPFS), overall survival (OS), pain response and toxicities graded using CTCAE version 4.03. Univariable and multivariable Cox proportional hazard regressions were performed to identify predictors for LPFS and OS. RESULTS: A total of 100 patients with 132 sites of PCSM were identified, with a median follow-up of 54 months. Fourteen-percent of patients underwent surgical intervention before receiving cEBRT. Eighteen spinal segments (13.6%) had local progression, with a median time to local progression of 8 months. The median LPFS and OS were 7.8 and 9.0 months, respectively. The complete and partial pain response rates were 57% and 39% respectively. The incidence of grade ≥3 acute toxicities was 11%. Better ECOG performance status (0 to 1), castration-sensitive disease, spinal surgery and use of novel antiandrogen agent were identified as significant predictors for improved OS on multivariable analysis. CONCLUSIONS: In our prostate cancer cohort, cEBRT is an effective treatment modality for local palliation of spinal metastases. More aggressive treatment approach should be considered for patients with excellent performance status and castration-sensitive disease in light of their expected longer survival. Further studies are warranted to identify the predictors for radiotherapy response in this population.

7.
Med Ultrason ; 22(3): 279-286, 2020 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-32898202

RESUMO

AIM: To compare the latest 2019 version of Bosniak classification (BCnew) against Bosniak classification prior to 2019 (BCold) using contrast-enhanced ultrasound (CEUS) and to compare CEUS against contrast-enhanced CT (CECT) based on BCnew. MATERIAL AND METHODS: Patients who had both CEUS and CECT of the kidneys performed within three months of each other were included. CECT and CEUS images of renal cysts were retrospectively analysed by two independent readers using BCnew, extrapolating the BCnew criteria to CEUS. Where histopathology was not available, 3-year imaging follow-up was used as a reference standard. RESULTS: Forty-nine patients with a total of 54 cysts were included. Using BCnew, Bosniak category between CEUS and CECT and both readers was concordant in 18 cysts (33.3%). Bosniak category between CEUS and CT was concordant in 27 cysts (50%) in reader 1 and in 33 cysts (61%) for reader 2. Based on Cohen's weighted kappa statistic (k), inter-observer agreement was moderate for CEUS (k=0.49) and fair for CECT (k=0.36). Agreement between CEUS and CECT for both readers was fair (reader 1, k=0.24; reader 2, k=0.37). Compared to using BCold, almost half of the benign cysts were assigned to a lower Bosniak category with CEUS using BCnew (reader 1, 42.6%; reader 2, 50%). CONCLUSIONS: CEUS assessment based on BCnew more appropriately assigns benign renal cysts to a lower category than CEUS based on BCold. Readers tend to grade renal cysts to a higher Bosniak category with BCnew but with greater inter-reader agreement on CEUS than on CECT.


Assuntos
Meios de Contraste , Aumento da Imagem/métodos , Doenças Renais Císticas/classificação , Doenças Renais Císticas/diagnóstico por imagem , Ultrassonografia/métodos , Idoso , Feminino , Humanos , Rim/diagnóstico por imagem , Masculino , Pessoa de Meia-Idade , Variações Dependentes do Observador , Reprodutibilidade dos Testes , Estudos Retrospectivos
8.
Quant Imaging Med Surg ; 10(9): 1811-1822, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32879859

RESUMO

Background: To evaluate the clinical utility of combined T2-weighted imaging and T2-mapping for the detection of prostate cancer. Methods: Forty patients underwent multiparametric magnetic resonance imaging (mpMRI) and T2-mapping of the prostate. Three readers each reviewed two sets of images: T2-weighted fast spin-echo (FSE) sequence (standard T2), and standard T2 in combination with T2-mapping. Each reader assigned probability scores for malignancy to each zone [peripheral zone (PZ) or transition zone (TZ)]. Inter-observer variability for standard T2 and combined standard T2 with T2-mapping were assessed. Diagnostic accuracy was compared between standard T2 and combined standard T2 with T2-mapping. Results: There was fair agreement between all three readers for standard T2 [intraclass correlation coefficient (ICC) =0.56] and combined standard T2 with T2-mapping (ICC =0.58). There was no significant difference in the area under the receiver operator characteristics curve for standard T2 compared to combined standard T2 with T2-mapping (0.89 vs. 0.82, P=0.31). Sensitivity (Sn) for combined standard T2 with T2-mapping was significantly higher compared to standard T2 alone (73.0% vs. 49.2%, P=0.006). Specificity (Sp) for combined standard T2 with T2-mapping was borderline significantly lower compared to standard T2 alone (89.3% vs. 94.9%, P=0.05). There was no significant differences between the negative predictive values (NPVs) and positive predictive values (PPVs) (P=0.07, P=0.45). Conclusions: Combination of T2-weighted imaging and T2-mapping could potentially increase Sn for prostate malignancy compared to T2-weighted imaging alone.

9.
Singapore Med J ; 2020 Aug 17.
Artigo em Inglês | MEDLINE | ID: mdl-32798363

RESUMO

INTRODUCTION: This study aimed to evaluate the potential of non-contrast enhanced magnetic resonance (MR) imaging as an imaging surveillance tool for hepatocellular carcinoma (HCC) detection in at-risk patients and to compare the performance of non-contrast MR imaging with ultrasonography (US) as a screening modality for the same. METHODS: In this retrospective study, patients diagnosed with HCC between 1 January 2010 and 31 December 2015 were selected from our institution's cancer registry. Patients with MR imaging and US scanning performed within three months of the MR imaging were included. For each MR imaging, two non-contrast MR imaging sequences - T2-weighted fat-saturated sequence (T2w-FS) and diffusion-weighted imaging (DWI) - were reviewed for the presence of suspicious lesions. A non-contrast MR image was considered positive if the lesion was seen on both sequences. The performance of non-contrast MR imaging was compared to that of hepatobiliary US for the detection of HCC. RESULTS: A total of 73 patients with 108 HCCs were evaluated. Sensitivity of non-contrast MR imaging for the detection of HCC using T2w-FS and DWI was 93.2%, which was significantly higher than that of US, at 79.5% (p = 0.02). In a subgroup of 55 patients with imaging features of liver cirrhosis, the sensitivity of non-contrast MR imaging was 90.9%, which was also significantly higher than US, at 74.5% (p = 0.02). CONCLUSION: Our pilot study showed that non-contrast MR imaging, using a combination of T2w-FS and DWI, is a potential alternative to US as a screening tool for the surveillance of patients at risk for HCC.

11.
Eur J Radiol ; 129: 109071, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32531720

RESUMO

PURPOSE: To evaluate if size-based cut-offs based on MR imaging can successfully assess clinically significant prostate cancer (csPCA). The goal was to improve the currently applied size-based differentiation criterion in PI-RADS. METHODS AND MATERIALS: MRIs of 293 patients who had undergone 3 T MR imaging with subsequent confirmation of prostate cancer on systematic and targeted MRI/TRUS-fusion biopsy were re-read by three radiologists. All identifiable tumors were measured on T2WI for lesions originating in the transition zone (TZ) and on DWI for lesions from the peripheral zone (PZ) and tabulated against their Gleason grade. RESULTS: 309 lesions were analyzed, 213 (68.9 %) in the PZ and 96 (31.1 %) in the TZ. ROC-Analysis showed a stronger correlation between lesion size and clinically significant (defined as Gleason Grade Group ≥ 2) prostate cancer (PCa) for the PZ (AUC = 0.73) compared to the TZ (AUC = 0.63). The calculated Youden index resulted in size cut-offs of 14 mm for PZ and 21 mm for TZ tumors. CONCLUSION: Size cut-offs can be used to stratify prostate cancer with different optimal size thresholds in the peripheral zone and transition zone. There was a clearer separation of clinically significant tumors in peripheral zone cancers compared to transition zone cancers. Future iterations of PI-RADS could therefore take different size-based cut-offs for peripheral zone and transition zone cancers into account.


Assuntos
Imageamento por Ressonância Magnética/métodos , Neoplasias da Próstata/diagnóstico por imagem , Neoplasias da Próstata/patologia , Idoso , Humanos , Biópsia Guiada por Imagem , Masculino , Imagem Multimodal/métodos , Próstata/diagnóstico por imagem , Próstata/patologia , Curva ROC , Estudos Retrospectivos , Sensibilidade e Especificidade , Ultrassonografia/métodos
12.
Urol Oncol ; 38(8): 650-660, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32505458

RESUMO

Targeted biopsy using multiparametric magnetic resonance imaging increases the detection rate of clinically significant prostate cancer (csCaP). In this meta-analysis, we compare the diagnostic accuracy of transrectal (TR) vs transperineal (TP) approaches for MRI-guided software fusion biopsy (FB) in the detection of csCaP. A literature search was performed in PubMed, Cochrane and Embase electronic databases up until July 2019 following the preferred reporting items for systematic review and meta-analysis system. The pooled sensitivity and specificity of either approach was evaluated using radical prostatectomy or systematic biopsies with ≥24 biopsy cores to be the reference standard. Fourteen papers with a total of 2002 patients were selected. Seven hundred and sixty-five patients underwent TR FB, while 1,387 underwent TP FB. One hundred and fifty of the patients underwent both TR and TP approaches. Both approaches were similar in terms of sensitivity (TR vs. TP: 0.81 vs 0.80) and specificity (TR vs. TP: 0.99 vs 0.95). In terms of likelihood ratios and diagnostic odds ratio, TR performed better than TP approach. The area under the receiving operator curve for both approaches was similar (0.91 vs 0.88 respectively). However, there was substantial heterogeneity across the studies for both approaches. TP and TR approaches to software-based FB yield similar diagnostic performance for the detection of csCaP. When deciding on the approach, physicians should consider other inherent features of either technique that suit their practice.


Assuntos
Imageamento por Ressonância Magnética/métodos , Neoplasias da Próstata/patologia , Ultrassonografia de Intervenção/métodos , Humanos , Biópsia Guiada por Imagem/métodos , Masculino , Períneo , Neoplasias da Próstata/diagnóstico por imagem , Reto
13.
Singapore Med J ; 2020 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-32460449

RESUMO

INTRODUCTION: Patients receiving intravenous iodinated contrast media (IOCM) for CT are predisposed to contrast-induced nephropathy. Chronic kidney disease is an important risk factor, and hydration is the mainstay of prevention. While inpatients can undergo intravenous hydration, there is a knowledge deficit regarding regimens for outpatients. We employed a rapid outpatient hydration protocol to reduce postponement of scan appointments for patients with suboptimal estimated glomerular filtration rate (eGFR). METHODS: From June 2015, we amended our CT preparation protocol to mandate rapid hydration (oral, intravenous or both) for patients with an eGFR of 30-60 mL/min/1.73 m2. Patients receiving this hydration protocol from June to November 2015 were followed up for one month to monitor any admissions for fluid overload, and up to one year to determine the long-term effect on eGFR. RESULTS: 226 outpatients received the hydration protocol, which correlated with a 95% reduction in postponement of imaging appointments. No complications of fluid overload from hydration were encountered. There was a significant association between age and decrease in eGFR, but this was not significant when stratified by drop in eGFR category. No statistical significance was found between decrease in eGFR and gender or race. Higher baseline eGFR was less likely to be associated with decrease in eGFR after imaging. Type of hydration was not related to a drop in eGFR category for patients with eGFR of 45-59 mL/min/1.73 m2. CONCLUSION: We defined a shorter hydration regimen that is safe to use in the outpatient setting.

14.
Medicine (Baltimore) ; 99(16): e19838, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32312006

RESUMO

Renal cell carcinoma (RCC) has been traditionally thought to be radioresistant. This retrospective cohort study aims to assess the outcomes of patients with spinal metastases from RCC treated with conventionally-fractionated external beam radiation therapy (cEBRT) in our institution.Patients diagnosed with histologically or radiologically-proven RCC who received palliative cEBRT to spinal metastases, using 3-dimensional conformal technique between 2009 and 2018 were reviewed. Local progression-free survival (PFS), overall survival (OS) and common terminology criteria for adverse events version 4.0-graded toxicity were assessed. Univariable and multivariable Cox proportional hazards regression analyses were performed to evaluate for predictors associated with survivals.Thirty-five eligible patients with forty spinal segments were identified, with a median follow-up of 7 months (range, 0-47). The median equivalent dose in 2 Gy fractions (EQD2) was 32.5 Gy 10 (range, 12-39). Thirty-seven percent of patients underwent surgical intervention. At the time of last follow-up, all but 1 patient had died. Seven patients developed local progression, with the median time to local progression of 10.2 months. The median local PFS and OS were 3.3 and 4.8 months. There was no grade 3 or higher toxicity. A higher radiation dose (equivalent dose to 2 Gy fraction <32.5 Gy 10 vs ≥32.5Gy 10) (hazard ratio [HR], 0.47; 95% confidence interval [CI], 0.17-3.18; P-value (P) = .68) and spinal surgery (HR, 2.35; 95% CI, 0.53-10.29; P = .26) were not significantly associated with local PFS on univariable analysis. Multivariable analysis showed that higher Tokuhashi score (HR, 0.41; 95% CI, 0.19-0.88; P = .02), lower number of spinal segments irradiated (HR, 1.18; 95% CI, 1.01-1.37; P = .04) and use of targeted therapy (HR, 0.41; 95% CI, 0.18-0.96; P = .04) were independent predictors for improved OS.For an unselected group of patients with RCC, there is no significant association between higher radiation dose and improved local control following cEBRT. This may be due to their short survivals. With the use of more effective systemic therapy, including targeted therapy and immunotherapy, survival will likely be prolonged. A tailored-approach is needed to identify patients with good prognosis who may still benefit from aggressive local treatments.


Assuntos
Carcinoma de Células Renais/complicações , Radiocirurgia/métodos , Neoplasias da Coluna Vertebral/radioterapia , Neoplasias da Coluna Vertebral/secundário , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Imunoterapia/métodos , Neoplasias Renais/patologia , Masculino , Pessoa de Meia-Idade , Terapia de Alvo Molecular/métodos , Intervalo Livre de Progressão , Radiocirurgia/efeitos adversos , Estudos Retrospectivos , Neoplasias da Coluna Vertebral/cirurgia , Coluna Vertebral/patologia , Coluna Vertebral/efeitos da radiação , Resultado do Tratamento
15.
Eur Radiol ; 30(8): 4262-4271, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32219507

RESUMO

OBJECTIVES: To assess the discriminatory power of lexicon terms used in PI-RADS version 2 to describe MRI features of prostate lesions. METHODS: Four hundred fifty-four patients were included in this retrospective, institutional review board-approved study. Patients received multiparametric (mp) MRI and subsequent prostate biopsy including MRI/transrectal ultrasound fusion biopsy and 10-core systematic biopsy. PI-RADS lexicon terms describing lesion characteristics on mpMRI were assigned to lesions by experienced readers. Positive and negative predictive values (PPV, NPV) of each lexicon term were assessed using biopsy results as a reference standard. RESULTS: From a total of 501 lesions, clinically significant prostate cancer (csPCa) was present in 175 lesions (34.9%). Terms related to findings of restricted diffusion showed PPVs of up to 52.0%/43.9% and NPV of up to 91.8%/89.7% (peripheral zone or PZ/transition zone or TZ). T2-weighted imaging (T2W)-related terms showed a wide range of predictive values. For PZ lesions, high PPVs were found for "markedly hypointense," "lenticular," "lobulated," and "spiculated" (PPVs between 67.2 and 56.7%). For TZ lesions, high PPVs were found for "water-drop-shaped" and "erased charcoal sign" (78.6% and 61.0%). The terms "encapsulated," "organized chaos," and "linear" showed to be good predictors for benignity with distinctively low PPVs between 5.4 and 6.9%. Most T2WI-related terms showed improved predictive values for TZ lesions when combined with DWI-related findings. CONCLUSIONS: Lexicon terms with high discriminatory power were identified (e.g., "markedly hypointense," "water-drop-shaped," "organized chaos"). DWI-related terms can be useful for excluding TZ cancer. Combining T2WI- with DWI findings in TZ lesions markedly improved predictive values. KEY POINTS: • Lexicon terms describing morphological and functional features of prostate lesions on MRI show a wide range of predictive values for prostate cancer. • Some T2-related terms have favorable PPVs, e.g., "water-drop-shaped" and "organized chaos" while others show less distinctive predictive values. DWI-related terms have noticeable negative predictive values in TZ lesions making DWI feature a useful tool for exclusion of TZ cancer. • Combining DWI- and T2-related lexicon terms for assessment of TZ lesions markedly improves PPVs. Most T2-related lexicon terms showed a significant decrease in PPV when combined with negative findings for "DW hyperintensity."


Assuntos
Neoplasias da Próstata/diagnóstico por imagem , Terminologia como Assunto , Adulto , Idoso , Idoso de 80 Anos ou mais , Humanos , Biópsia Guiada por Imagem , Idioma , Imageamento por Ressonância Magnética/métodos , Masculino , Pessoa de Meia-Idade , Imageamento por Ressonância Magnética Multiparamétrica , Neoplasias da Próstata/patologia , Radiologia , Estudos Retrospectivos , Ultrassonografia
16.
Singapore Med J ; 60(11): 554-559, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31781779

RESUMO

Lung cancer is the leading cause of cancer-related death around the world, being the top cause of cancer-related deaths among men and the second most common cause of cancer-related deaths among women in Singapore. Currently, no screening programme for lung cancer exists in Singapore. Since there is mounting evidence indicating a different epidemiology of lung cancer in Asian countries, including Singapore, compared to the rest of the world, a unique and adaptive approach must be taken for a screening programme to be successful at reducing mortality while maintaining cost-effectiveness and a favourable risk-benefit ratio. This review article promotes the use of low-dose computed tomography of the chest and explores the radiological challenges and future directions.


Assuntos
Detecção Precoce de Câncer/métodos , Neoplasias Pulmonares/diagnóstico por imagem , Programas de Rastreamento/métodos , Radiologia/organização & administração , Tomografia Computadorizada por Raios X/métodos , Algoritmos , Ensaios Clínicos como Assunto , Análise Custo-Benefício , Aprendizado Profundo , Diagnóstico por Computador , Europa (Continente) , Reações Falso-Positivas , Humanos , Comunicação Interdisciplinar , Guias de Prática Clínica como Assunto , Saúde Pública , Doses de Radiação , Sistema de Registros , Medição de Risco , Singapura/epidemiologia , Abandono do Hábito de Fumar , Estados Unidos
17.
Eur Radiol ; 29(12): 6982-6990, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31264013

RESUMO

OBJECTIVES: To intraindividually compare the signal-enhancing effect of 0.5 M gadoterate meglumine and 1.0 M gadobutrol in dynamic contrast-enhanced magnetic resonance (DCE-MR) imaging of the prostate. METHODS: Fifty patients who underwent two 3-T MR examinations of the prostate were included in this IRB-approved retrospective uncontrolled, unrandomized study. All received two scans (mean time interval, 20.5 months) including T1-weighted DCE-MR imaging, one with 0.5 M gadoterate meglumine and one with 1.0 M gadobutrol. Equimolar doses of gadolinium (0.1 mmol/kg body weight) were administered with identical injection speed (2 mL/s), resulting in differing gadolinium delivery rate. An identical region of interest (ROItz) within a BPH-node was identified on both scans. The area under the time-enhancement curve of each ROItz from 0 to 180 s post contrast arrival and pharmacokinetic parameters were calculated. Relative enhancement and signal-to-noise (SNR) and contrast-to-noise (CNR) ratios in the delayed phase at about 180 s were compared between both agents. RESULTS: There was a significantly larger area under the time-enhancement curve (5.53 vs 4.97 p = 0.0007) and higher relative enhancement of BPH nodules (2.23 vs 1.96 p < 0.0001) with gadobutrol compared with gadoterate meglumine. There were no significant differences in SNR (44.55 vs 37.63 p = 0.12), CNR (31.22 vs 26.39 p = 0.18), and pharmacokinetic parameters Ktrans (0.31 vs 0.32 p = 0.86), Ve (1.36 vs 0.98 p = 0.13), and Kep (0.34 vs 0.36 p = 0.12). CONCLUSIONS: At equimolar doses, increased gadolinium delivery over time using gadobutrol provides higher relative enhancement parameters in BPH nodules compared with gadoterate meglumine, but does not translate into improved SNR or CNR. KEY POINTS: • At equal injection rate and equimolar total dose, gadobutrol compared with gadoterate meglumine provides a significantly greater relative enhancement in DCE-MR imaging of BPH over the first 180 s. • There are no significant differences in SNRs, CNRs, and pharmacokinetic parameters between the two GBCAs.


Assuntos
Imageamento por Ressonância Magnética/métodos , Meglumina/farmacologia , Compostos Organometálicos/farmacologia , Próstata/diagnóstico por imagem , Doenças Prostáticas/diagnóstico , Idoso , Meios de Contraste/farmacologia , Gadolínio , Humanos , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Estudos Retrospectivos
19.
Singapore Med J ; 60(4): 193-198, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30182131

RESUMO

INTRODUCTION: Thyroid fine-needle aspiration cytology (FNAC) is an established investigation for the preoperative evaluation of thyroid nodules and is often done under ultrasonography guidance. While its accuracy has been widely reported, there is little evidence in the literature on the approach to non-diagnostic cytology results. In our study, we aimed to determine the diagnostic performance of ultrasonography-guided thyroid FNAC for the preoperative diagnosis of thyroid cancer at our institution and evaluate the significance of a non-diagnostic thyroid FNAC. METHODS: We retrospectively reviewed the thyroid ultrasonography studies and medical records of all patients who underwent both thyroid FNAC and subsequent thyroid surgery at our institution from 2011 to 2013. FNAC results were correlated with the final histological diagnosis from surgery and the ultrasonography studies were reviewed for suspicious sonographic features. RESULTS: FNAC predicted malignancy with sensitivity, specificity, positive predictive value, negative predictive value, false positive rate, false negative rate and total accuracy of 90.7%, 53.6%, 43.3%, 93.7%, 46.4%, 9.3% and 64.1%, respectively. We found that only one of 26 nodules with non-diagnostic FNAC results was proven malignant on a second FNAC and subsequent thyroidectomy. CONCLUSION: The accuracy of ultrasonography-guided FNAC at our institution was comparable to that reported in the literature. There appears to be very low probability of malignancy in sonographically benign nodules with initial non-diagnostic FNAC results.


Assuntos
Biópsia por Agulha Fina , Biópsia Guiada por Imagem , Neoplasias da Glândula Tireoide/patologia , Ultrassonografia de Intervenção , Feminino , Humanos , Masculino , Valor Preditivo dos Testes , Estudos Retrospectivos , Sensibilidade e Especificidade , Singapura , Neoplasias da Glândula Tireoide/cirurgia , Tireoidectomia
20.
J Endourol ; 31(11): 1111-1116, 2017 11.
Artigo em Inglês | MEDLINE | ID: mdl-28797178

RESUMO

OBJECTIVE: To test the hypothesis that targeted biopsy has a higher detection rate for clinically significant prostate cancer (csPCa) than systematic biopsy. We defined csPCa as any Gleason sum ≥7 cancer. In patients with Prostate Imaging Reporting and Data System (PI-RADS) 3 lesions, to determine if factors, such as prostate-specific antigen density (PSAD) and prostate health index (PHI), can predict csPCa and help select patients for biopsy. MATERIALS AND METHODS: We report the first series of targeted biopsies in Southeast Asian men, with comparison against systematic biopsy. Consecutive patients were registered into a prospective institutional review board-approved database in our institution. We reviewed patients who underwent biopsy from May 2016 to June 2017. Inclusion criteria for our study were patients with at least one PI-RADS ≥3, and who underwent both targeted and systematic biopsies in the same sitting. RESULTS: There were 115 patients in the study, of whom 74 (64.3%) had a previous negative systematic biopsy. Targeted biopsies detected significantly less Gleason 6 cancers than systematic biopsies (p < 0.01), and demonstrated significantly higher sensitivity, specificity, positive predictive value, and negative predictive value (NPV) for the detection of csPCa. For patients with PI-RADS 3 lesions, PHI and PSAD were found to be the best predictors for csPCa. PSAD <0.10 ng/mL/mL had an NPV of 93% and sensitivity of 92%, while allowing 20% of patients to avoid biopsy. PHI cutoff of <27 would allow 34% of patients to avoid biopsy, with both sensitivity and NPV of 100%. CONCLUSIONS: Targeted prostate biopsies were found to be significantly superior to systematic biopsies for the detection of csPCa, while detecting less Gleason 6 cancer. Usage of PSAD and PHI cutoff levels in patients with PI-RADS 3 lesions may enable a number of patients to avoid unnecessary biopsy.


Assuntos
Biópsia Guiada por Imagem , Imageamento por Ressonância Magnética , Antígeno Prostático Específico/sangue , Neoplasias da Próstata/diagnóstico por imagem , Idoso , Grupo com Ancestrais do Continente Asiático , Humanos , Masculino , Gradação de Tumores , Valor Preditivo dos Testes , Estudos Prospectivos , Neoplasias da Próstata/sangue , Neoplasias da Próstata/patologia , Sensibilidade e Especificidade , Singapura
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