scholarly journals An Iterative Algorithm for Semisupervised Classification of Hotspots on Bone Scintigraphies of Patients with Prostate Cancer

2021 ◽  
Vol 7 (8) ◽  
pp. 148
Author(s):  
Laura Providência ◽  
Inês Domingues ◽  
João Santos

Prostate cancer (PCa) is the second most diagnosed cancer in men. Patients with PCa often develop metastases, with more than 80% of this metastases occurring in bone. The most common imaging technique used for screening, diagnosis and follow-up of disease evolution is bone scintigraphy, due to its high sensitivity and widespread availability at nuclear medicine facilities. To date, the assessment of bone scans relies solely on the interpretation of an expert physician who visually assesses the scan. Besides this being a time consuming task, it is also subjective, as there is no absolute criteria neither to identify bone metastases neither to quantify them by a straightforward and universally accepted procedure. In this paper, a new algorithm for the false positives reduction of automatically detected hotspots in bone scintigraphy images is proposed. The motivation relies in the difficulty of building a fully annotated database. In this way, our algorithm is a semisupervised method that works in an iterative way. The ultimate goal is to provide the physician with a fast, precise and reliable tool to quantify bone scans and evaluate disease progression and response to treatment. The algorithm is tested in a set of bone scans manually labeled according to the patient’s medical record. The achieved classification sensitivity, specificity and false negative rate were 63%, 58% and 37%, respectively. Comparison with other state-of-the-art classification algorithms shows superiority of the proposed method.

2009 ◽  
Vol 23 (4) ◽  
pp. 422-425 ◽  
Author(s):  
Yee-Jee Jan ◽  
Su-Ju Chen ◽  
John Wang ◽  
Rong-San Jiang

Background Liquid-based cytology (LBC) has achieved great success in cytological diagnosis of various cancers when compared with conventional smear methods. However, its application in diagnosing nasopharyngeal carcinoma (NPC) has never been studied. Methods Eighty-four consecutive patients who underwent nasopharyngeal biopsy for suspicious NPC or a nasopharyngeal mass under nasopharyngoscopy were enrolled in this prospective study. Brush samples were taken from the same site before punch biopsy and processed with the Thin Prep test. Results The adequacy, accuracy, sensitivity, specificity, false-negative rate, and false-positive rate of LBC in diagnosing NPC were 92.9% (78 of 84), 93.6% (73 of 78), 84.2% (16 of 19), 96.6% (57 of 59), 15.8% (three of 19), and 3.4% (two of 25), respectively. There were four inadequate specimens from patients with NPC and two inadequate ones from those without NPC. Conclusions Our study showed that the adequacy, accuracy, sensitivity, specificity, and diagnostic rate of LBC were equivalent to those using conventional smear methods. Although the diagnostic rate of NPC was lower using brush cytology than by punch biopsy, further improvements in the sampling technique could make brushing cytology a potential tool for NPC screening.


Author(s):  
Harikrishna Mulam ◽  
Malini Mudigonda

Many research works are in progress in classification of the eye movements using the electrooculography signals and employing them to control the human–computer interface systems. This article introduces a new model for recognizing various eye movements using electrooculography signals with the help of empirical mean curve decomposition and multiwavelet transformation. Furthermore, this article also adopts a principal component analysis algorithm to reduce the dimension of electrooculography signals. Accordingly, the dimensionally reduced decomposed signal is provided to the neural network classifier for classifying the electrooculography signals, along with this, the weight of the neural network is fine-tuned with the assistance of the Levenberg–Marquardt algorithm. Finally, the proposed method is compared with the existing methods and it is observed that the proposed methodology gives the better performance in correspondence with accuracy, sensitivity, specificity, precision, false positive rate, false negative rate, negative predictive value, false discovery rate, F1 score, and Mathews correlation coefficient.


2020 ◽  
Vol 41 (Supplement_2) ◽  
Author(s):  
H Tjora ◽  
O.T Steiro ◽  
J Langorgen ◽  
T Omland ◽  
P Collinson ◽  
...  

Abstract Background Rapid rule-out algorithms for non-ST-elevation infarction (NSTEMI) may be beneficial for logistics in the emergency room. Current algorithms are designed to rule-out NSTEMI, but do not differentiate between unstable angina (UAP) in need of revascularization and non-cardiac chest pain patients (NCCP) who could be discharged. Recent improvements in analytical precision of high sensitivity troponin (cTn) assays allow for trialing algorithms with very small delta values. Purpose Could the use of lower delta values produce rule-out algorithms for NSTE-ACS with a false negative rate of ≤5%, and a sufficient high rule-out rate of patients with NCCP. Method 927 patients with suspected NSTE-ACS were consecutively included. Serum samples were collected at 0, 3 and 8–12 hours. The final diagnosis was adjudicated by two independent cardiologists based on all clinical data including routine cTnT. The 0- and 3-hour samples were additionally measured for cTnIand cTnI from Singulex Clarity System (cTnI(sgx)). The diagnostic performance to rule-out NSTE-ACS was compared between one low-delta value algorithm from each assay (cTnT, cTnI and cTnT). Results The prevalence of NSTEMI was 13.4%, UAP 11.4% and NCCP 60%. Median age was 63 years, 60% males. Fig. 1 shows baseline and 3-hour delta cTn values for the UAP and NCCP patients for the three different assays. The baseline cTn value differed significantly between UAP and NCCP for all assays, p value <0.001. The novel low-delta cTnT algorithm (Table 1) ruled out 8 NSTE-ACS patients (3.5%), the cTnI algorithm and cTnI (sgx) algorithm ruled out 11 (4.8%) and 12 (5.2%) patients with NSTE-ACS, respectively. Moreover, the cTnT algorithm allocated 35.3% of the NCCP patients to discharge. Respective numbers for the cTnI(sgx) and cTnI algorithm were 30.6% and 33.5%. Comparing the ROC curves, the cTnT algorithm had significantly higher AUC compared to the cTnI(sgx) algorithm (p value =0.005, DeLong test). Conclusion The low-delta value algorithms correctly ruled in ≥95% of the NSTE-ACS patients whilst >30% of NCCP patients were ruled out. The cTnT algorithm had the best performance with a significant higher AUC compared to the cTnI(sgx) algorithm. Figure 1 Funding Acknowledgement Type of funding source: Public Institution(s). Main funding source(s): Western Norway Regional Health Authority, Haukeland and Stavanger University hospital


2020 ◽  
Vol 38 (15_suppl) ◽  
pp. 1047-1047
Author(s):  
Ning Liao ◽  
RongFeng Song ◽  
FangQin Xue ◽  
Shuirong Zhang ◽  
Samuel J Klempner ◽  
...  

1047 Background: Establishment of ERBB2 ( HER2) amplification status in breast carcinoma (BC) and gastric carcinoma (GC) is essential for treatment selection, but no anti- HER2 therapies have been approved for tumors with low level of HER2 expression. The clinical trial ( NCT02564900 ) was initiated to evaluate the safety and efficacy of trastuzumab deruxtecan (DS-8201a) in BC patients with lower HER2 expression by current methods. This study aims to validate NGS-based detection for HER2 low expression. Methods: 275 BC and 425 GC were collected and subjected to NGS for genomic alteration detection. The testing was carried out by a College of American Pathologists (CAP) accredited and Clinical Laboratory Improvement Amendments (CLIA) certified laboratory, Shanghai, China. Protein expression was analyzed by using IHC. FISH was carried out on 108 samples, including 63 BC and 45 GC. To set up NGS cutoff, FISH was performed on additional 34 samples. Sensitivity, specificity and accuracy were evaluated based on FISH as a gold-standard reference. Results: In BC, the expression level of HER2 protein detected by IHC was overall IHC 0 in 28.7%, 1+ in 18.9%, 2+ in 27.3% and 3+ in 25.1%, respectively, while in GC, the expression level was 60.7%, 18.6%, 14.8% and 5.9%, respectively. Log2ratio was used to assess ERBB2 amplification status detected by NGS. According to the FISH results of 34 other samples with high sensitivity (98%) and specificity (100%), the threshold was determined as 0.5. 8 and 10 samples of IHC 1+/2+ met the cutoff in BC and GC, respectively. In 63 BC, there were 17 positive and 46 negative by FISH. According to the threshold, the sensitivity and specificity of NGS detection was 94.1% and 97.8%, respectively. The proportion of samples with IHC 2+ that couldn't determine NGS ERBB2 status was 49.2%. However, except for false positive and false negative, the NGS results were concordant with FISH. In 45 GC, there were 5 positive and 40 negative by FISH. The specificity and sensitivity was 97.5% and 40%, respectively. In 4 samples with IHC 2+, 2 of them were discordant with the results of NGS and FISH. All IHC 1+ didn't meet the cutoff of NGS and was FISH negative in 108 samples. The accuracy of NGS in ERBB2 detection was 96.8% and 91.1% for BC and GC, respectively. Conclusions: Our data indicated that the NGS-based detection of ERBB2 amplification had high sensitivity, specificity and accuracy. In samples with IHC 1+/2+, the results of NGS detection were high concordant with FISH detection.


Nanomaterials ◽  
2021 ◽  
Vol 12 (1) ◽  
pp. 33
Author(s):  
Sungje Bock ◽  
Hyung-Mo Kim ◽  
Jaehi Kim ◽  
Jaehyun An ◽  
Yun-Sik Choi ◽  
...  

Prostate cancer can be detected early by testing the presence of prostate-specific antigen (PSA) in the blood. Lateral flow immunoassay (LFIA) has been used because it is cost effective and easy to use and also has a rapid sample-to-answer process. Quantum dots (QDs) with very bright fluorescence have been previously used to improve the detection sensitivity of LFIAs. In the current study, a highly sensitive LFIA kit was devised using QD-embedded silica nanoparticles. In the present study, only a smartphone and a computer software program, ImageJ, were used, because the developed system had high sensitivity by using very bright nanoprobes. The limit of PSA detection of the developed LFIA system was 0.138 ng/mL. The area under the curve of this system was calculated as 0.852. The system did not show any false-negative result when 47 human serum samples were analyzed; it only detected PSA and did not detect alpha-fetoprotein and newborn calf serum in the samples. Additionally, fluorescence was maintained on the strip for 10 d after the test. With its high sensitivity and convenience, the devised LFIA kit can be used for the diagnosis of prostate cancer.


Author(s):  
Mohammadreza Akhlaghi ◽  
Masoomeh Zarei ◽  
Majid Ziaei ◽  
Mohsen Pourazizi

Purpose: This study evaluated the sensitivity, specificity, and diagnostic accuracy of Color Doppler Ultrasonography (CDUS) in patients with suspected retinal detachment (RD) who underwent surgery. Methods: In this prospective, observational clinical study, 65 eyes of 65 consecutive patients with suspected RD with opaque media were included. Following a standardized protocol, CDUS of the retina of the affected eye was performed. The sensitivity, specificity, and diagnostic accuracy of CDUS were determined and compared to the findings during surgery. Results: The mean age of patients (18 men and 47 women) was 52.36 years (range: 8–77 years). The sensitivity, specificity, and overall accuracy of ocular CDUS were 91.3%, 88.1%, and 89.2%, respectively. The false-negative rate (negative CDUS images but presence of RD at operation) was 3.1% (2/65) and the false-positive rate (positive CDUS images but absence of RD at operation) was 7.7% (5/65). Conclusion: CDUS of the retina could be considered as a promising tool in the diagnosis of RD in patients with opaque media.


2011 ◽  
Vol 50 (03) ◽  
pp. 107-115 ◽  
Author(s):  
K.T Tabasi ◽  
S. M. M Bazaz ◽  
V. R. D Kakhki ◽  
A. F Massoom ◽  
H Gholami ◽  
...  

SummaryAim: Sentinel node (SN) biopsy is becoming a standard procedure in the management of several malignancies. Several groups have evaluated the feasibility and value of this procedure in prostate cancer patients. In the current meta-analysis, we comprehensively and quantitatively summarized the results of these studies. Methods: Several databases including Medline, SCOPUS, Google Scholar, Ovid, Springer, and Science direct were systematically searched for the relevant studies regarding SL biopsy in the prostate cancer (“prostate” AND “sentinel” as search keywords). The outcomes of interest were sensitivity and detection rate of the procedure. Results: For detection rate and sensitivity 21 and 16 studies met the criteria of inclusion respectively. Pooled detection rate was 93.8% (95% CI 89–96.6%). Cochrane Q value was 216.077 (I2 = 89.81% and p < 0.001). Pooled sensitivity was 94% (95% CI 91–96%). Cochrane Q value was 14.12 (I2 = 0.0 and p = 0.516). Conclusion: SL biopsy can prevent unnecessary pelvic lymph node dissection in prostate cancer patients. This procedure is feasible with low false negative rate and high detection rate.


2004 ◽  
Vol 87 (2) ◽  
pp. 417-423 ◽  
Author(s):  
Esther Trullols ◽  
Itziar Ruisánchez ◽  
F Xavier Rius ◽  
Marta Ódena ◽  
M Teresa Feliu

Abstract The proper characterization of a commercial qualitative method for determining aflatoxin B1 in some nuts is described. A qualitative method that provides binary responses of the yes/no type means that the performance parameters have been properly adapted and defined. Performance characteristics such as the cut-off limit, the detection limit, sensitivity, specificity, false-positive and negative rates, and the unreliability or uncertainty region are defined and then estimated by means of the performance characteristic curves. The commercial test kit showed the cut-off limit at 1.6 ng/g, with a sensitivity rate of 95% and a false-negative rate of zero. A modification can be performed to shift the cut-off to 2.0 ng/g, keeping the same values for the sensitivity and false-negative rate.


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