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62 result(s) for "Mokhtar, Alaa"
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The grasper-integrated disposable flexible cystoscope is comparable to the reusable, flexible cystoscope for the detection of bladder cancer
Flexible cystoscopy under local anaesthesia is standard for the surveillance of bladder cancer. Frequently, several reusable cystoscopes fail to reprocess. With the new grasper incorporated single-use cystoscope for retrieval of ureteric stents, we explored the feasibility of using it off-label for diagnosis and the detection of bladder cancer. Consecutive diagnostic flexible cystoscopies between Mar 2016 and Nov 2018 were reviewed comparing the reusable versus the disposable cystoscopes. A total of 390 patients underwent 1211 cystoscopies. Median age was 61.5 years (SD 14.2, 18.8–91.4), males 331 (84.9%) and females 59 (15.1%). Indication for cystoscopy was prior malignancy in 1183 procedures (97.7%), haematuria 19 (1.6%) or bladder mass 7 (0.6%). There were 608 reusable and 603 disposable cystoscopies. There was no significant difference between groups at baseline in age, sex, BMI, smoking status, or prior tumor risk category. There was no significant difference in positive findings (123/608, 20.2% vs 111/603, 18.4%, p  = 0.425) or cancer detection rates (95/608, 15.6% vs 88/603, 14.4%, p 0.574) among the two groups, respectively. We conclude that the disposable grasper integrated cystoscope is comparable to reusable cystoscope in the detection of bladder cancer.
Trimodal therapy versus radical cystectomy for cT2N0M0 urothelial muscle-invasive bladder cancer: Single-center experience
Abstract Background: Bladder cancer is ranked the ninth most common cancer in the world. Locally, the incidence of bladder cancer has increased tenfold over the past 26 years. Radical cystectomy (RC) is considered a gold standard management option for muscle-invasive bladder cancer (MIBC), but trimodal therapy (TMT) has shown comparable oncological outcomes in selected patients. Materials and Methods: This is a retrospective study in which we reviewed medical records of patients diagnosed with MIBC without nodal disease or distant metastasis (cT2N0M0) who underwent either RC or TMT. Demographic data, comorbidities, histopathological and clinical staging, neoadjuvant/adjuvant therapy, and follow-up were analyzed. Results: We included a total of 31 patients in the study, with 10 patients in the TMT group and 21 patients in the RC group. There was no significant difference in recurrence between the TMT and RC groups (P = 0.58). The TMT group had a higher percentage of local recurrence (40% vs. RC 5.2%, P = 0.018) but no significant difference in metastasis (0% vs. 10%, P = 0.420). The difference in overall survival between the TMT and RC groups was not significant (P = 0.25). Conclusion: TMT may be considered an alternative option for patients unwilling to undergo RC due to related complications and prioritize a better quality of life. However, the decision should be made after considering the cost of extensive follow-ups and patient compliance with surveillance.
Prediction of prostate biopsy outcomes at different cut-offs of prostate-specific antigen using machine learning: a multicenter study
Machine learning (ML) is a significant area of artificial intelligence, which can improve the accuracy of predictive or diagnostic models for differentiating between prostate biopsy outcomes. This study aims to develop a novel decision-support ML model for classifying patients with biopsy-negative (cancer-free), clinically significant, and non-clinically significant prostate cancer across two prostate-specific antigen (PSA) cut-offs 10 ng/ml and > 10 ng/ml. The data for the current study were retrieved from the records of two main hospitals in Riyadh, Saudi Arabia from July 2018 through July 2024. Six machine learning algorithms were employed, and the dataset was randomly divided into a training set and a validation set at a ratio of 8:2. The following metrics were used as performance indicators across the six algorithms: Accuracy, Precision, Recall, F1-score, and area under the curve. Recent data from the two hospitals was utilized for external validation. The metrics for Random Forest, Extra Tree, and Decision Tree algorithms showed excellent capability in classifying the outcomes of prostate biopsy for the two PSA cut-offs. However, the metrics for the PSA cut-off > 10 ng/ml are higher than those for PSA 10 ng/ml. For the three-class classification, the accuracy and area under the curve for the cut-off > 10 ng/ml were 0.96 and 0.99, respectively. While for the cut-off 10 ng/ml they were 0.92 and 0.94 for Random Forest and 0.94 and 0.95 for the Extra Tree algorithm. The metrics of non-clinically significant and biopsy-negative cases outperformed those of clinically significant cases. ML models are proving to be effective tools in differentiating between prostate biopsy outcomes, enhancing diagnostic accuracy, and potentially transforming clinical practices in prostate cancer management.
Squamous cell carcinoma of the bilharzial and non-bilharzial urinary bladder: a review of etiological features, natural history, and management
Squamous cell carcinoma of the urinary bladder, though uncommon in Europe and the United States, is the most common variety of bladder tumor in countries where urinary bilharziasis prevails. A great controversy still exists regarding its natural history and management. Here, we review the literature of bilharzial and nonbilharzial squamous cell carcinoma of the urinary bladder, focusing on large series. Our aim was to gather most of the published data about this disease entity, report it in a systematic comparative review, and attempt to identify the adverse features and variables behind its dismal outcome. The conclusions are that squamous cell carcinoma, whether bilharzial or nonbilharzial, has distinctive clinicopathological features, different from those of the transitional cell variety. These tumors usually present in advanced (muscle-invasive) stages. Pelvic nodal metastases are not common, and the incidence of distant metastases is less than that reported with transitional cell carcinoma. Local treatment, including cystectomy and adjunctive radiotherapy, is the most acceptable way of treating such tumors.
Is survival after radical cystectomy for bladder cancer in Saudi patients different from that of Western patients?
Although radical cystectomy (RC) is considered the gold standard treatment of muscle invasive bladder cancer, nearly half of patients develop metastases and ultimately die within 2 years. To assess survival, evaluate different prognostic factors that may affect disease-free survival (DFS) in Saudi patients after RC for carcinoma of the bladder and to compare our results with those of Western countries. Retrospective chart review. A tertiary care center in Saudi Arabia. We collected data on patients who underwent RC for bladder cancer in the period between 1979 and 2014. Demographic, clinical and pathological variables and the application of perioperative chemotherapy were reviewed. Univariate and multivariate analyses were done with DFS as the end point. Disease-specific survival. On 328 patients for whom data was available, the median follow up was 23 months (range, 2 month-28 years) and median age was 58 years (range, 21-90). Of these patients, 268 were males (81.7%), 235 (71.7%) had urothelial carcinoma (UC), 79 (24.1%) had squamous cell carcinoma (SCC), and 208 (63.4%) had pathological tumor stage 3 or more. The 5-year overall survival (OS) and DFS were 52% and 48%, respectively. There was no statistically significant difference in DFS of patients with UC and pure SCC. On univariate analysis, lymph node status and pathological tumor stage were significant predictors of DFS. Both variables sustained statistical significance in a multivariate analysis. Survival following RC is almost the same as others. Moreover, pathological tumor stage and lymph node metastasis were the only independent predictors for survival following RC. Future cooperative prospective studies are required to gain data on our region. Relatively small sample size and retrospective.
Prospective randomized trial of 100u vs 200u botox in the treatment of idiopathic overactive bladder
To evaluate the clinical outcomes of two different doses of BTX-A in patients with refractory idiopathic overactive bladder. Thirty nine patients with refractory idiopathic overactive bladder from 1/1/2008 till 30/3/2009 were evaluated in a tertiary care hospital. Patients were evaluated using urodynamic studies, voiding diary, UDI-6 and IIQ-7 questionnaires prior to being prospectively randomized (alternate randomization) to the BTX-A applications and three months after treatment. Voiding diary and residual volume were followed two weeks later. All patients received intradetrusorial injections of BTX-A (Botox, Allergan, Irvine, CA) of 100u or 200u under cystoscopic control on an outpatient basis. The primary endpoint was assessed for the improvement of urodynamic parameters and adverse events at three months after the initial treatment. Secondary end points included urinary frequency, urgency and UUI episodes as assessed by voiding diary and QoL. Eleven patients were enrolled to each arm of the study. There were no significant differences in demographic characteristics between the two groups. Urodynamic assessment at the end of the third month showed significant improvement in urodynamic variables in both groups. There was no statistically significant difference in urodynamic parameters and in the voiding diary between the two groups. QOL was significantly improved in both groups with no statistically significant difference between the different doses. Only three patients developed acute urinary retention. BTX-A at 100u and 200u appears to improve symptoms, urodynamic parameters and QoL with no statistical significance between the two groups.
Predictors of viable germ cell tumor in postchemotherapeutic residual retroperitoneal masses
Objective: The aim of this study was to identify predictors of viable germ cell tumor (GCT) in postchemotherapeutic residual retroperitoneal masses. Materials and Methods: The pertinent clinical and pathologic data of 16 male patients who underwent postchemotherapeutic retroperitoneal lymph node dissection (PC-RPLND) at King Faisal Specialist Hospital and Research Centre between 1994 and 2005 were reviewed retrospectively. It was found that all patients received cisplatin-based chemotherapy for advanced testicular GCT. Results: Out of the 16 male patients, 2 (13%), 8 (50%), and 6 (37%) had viable GCT, fibrosis, and teratoma, respectively. Ten (10) of the patients with prechemotherapeutic S1 tumor markers did not have viable GCT, and two of the six patients who had prechemotherapeutic S2 tumor markers have viable GCT. All tumor marker levels normalized after chemotherapy even in patients with viable GCT. Four patients had vascular invasion without viable GCT. Furthermore, four patients had more than 60% embryonal elements in the original pathology, but only 1 had viable GCT at PC-RPLND. Four of the five patients with immature teratoma had teratoma at PC-RPLND but no viable GCT; however, out of the four patients with mature teratoma, one had viable GCT and two had teratoma at PC-RPLND. Of the two patients with viable GCT, one had 100% embryonal cancer in the original pathology, prechemotherapeutic S2 tumor markers, history of orchiopexy, and no vascular invasion; the other patient had yolk sac tumor with 25% embryonal elements and 40% teratoma in the original pathology, and prechemotherapeutic S2 tumor markers. Conclusion: None of the clinical or pathological parameters showed a strong correlation with the presence of viable GCT in PC-RPLND. However, patients with ≥S2 may be at higher risk to have viable GCT. Further studies are needed to clarify this.
Isolated ureteric endometriosis presenting as a ureteric tumor
A 32 year old lady presented with recurrent left flank pain for 4 weeks and chronic lower back pain. CT without contrast showed no stones and mild left hydronephrosis. CT of the spine suggested an inflammatory process at L5-S1 vertebra. The diagnosis was supported by a bone scan. Incidentally, the scan showed nonfunctioning left kidney. Diuretic renography confirmed poor perfusion and no excretion. A retrograde study showed narrowing of the ureter at the pelvic brim. Ureteroscopy showed a papillary mass in the lumen of the ureter from which multiple cold cup biopsies were taken. The pathology however was not conclusive. A robotic nephroureterectomy was carried out. Definitive pathology showed intrinsic endometriosis of the ureter. We conclude that endometriosis should be considered in the differential diagnosis of unexplained ureteric obstruction and ureteric lumen filling defects in young women.
Does Machine Learning Prediction of Magnetic Resonance Imaging PI-RADS Correlate with Target Prostate Biopsy Results?
This study aimed to predict and classify MRI PI-RADs scores using different machine learning algorithms and to detect the concordance of PI-RADs scoring with the outcome target of prostate biopsy.OBJECTIVESThis study aimed to predict and classify MRI PI-RADs scores using different machine learning algorithms and to detect the concordance of PI-RADs scoring with the outcome target of prostate biopsy.Machine learning (ML) algorithms were used to develop best-fitting models for the prediction and classification of MRI PI-RAD. The Random Forest and Extra Trees models achieved the best performance compared to the other methods.METHODSMachine learning (ML) algorithms were used to develop best-fitting models for the prediction and classification of MRI PI-RAD. The Random Forest and Extra Trees models achieved the best performance compared to the other methods.The accuracy of both models was 91.95%. The AUC was 0.9329 for the Random Forest model and 0.9404 for the Extra Trees model. PSA level, PSA density, and diameter of the largest lesion were the most important features for the importance of outcome classification. ML prediction enhanced the PI-RAD classification, where clinically significant prostate cancer (csPCa) cases increased from 0% to 1.9% in the low-risk PI-RAD class, this showed that the model identified some previously missed cases.RESULTSThe accuracy of both models was 91.95%. The AUC was 0.9329 for the Random Forest model and 0.9404 for the Extra Trees model. PSA level, PSA density, and diameter of the largest lesion were the most important features for the importance of outcome classification. ML prediction enhanced the PI-RAD classification, where clinically significant prostate cancer (csPCa) cases increased from 0% to 1.9% in the low-risk PI-RAD class, this showed that the model identified some previously missed cases.Predictive machine learning models showed an excellent ability to predict MRI Pi-RAD scores and discriminate between low- and high-risk scores. However, caution should be exercised, as a high percentage of negative biopsy cases were assigned Pi-RAD 4 and Pi-RAD 5 scores. ML integration may enhance PI-RAD's utility by reducing unnecessary biopsies in low-risk patients (via better csPCa detection) and refining the high-risk categorization. Combining such PI-RAD scores with significant parameters, such as PSA density, lesion diameter, number of lesions, and age, in decision curve analysis and utility paradigms would assist physicians' clinical decisions.CONCLUSIONSPredictive machine learning models showed an excellent ability to predict MRI Pi-RAD scores and discriminate between low- and high-risk scores. However, caution should be exercised, as a high percentage of negative biopsy cases were assigned Pi-RAD 4 and Pi-RAD 5 scores. ML integration may enhance PI-RAD's utility by reducing unnecessary biopsies in low-risk patients (via better csPCa detection) and refining the high-risk categorization. Combining such PI-RAD scores with significant parameters, such as PSA density, lesion diameter, number of lesions, and age, in decision curve analysis and utility paradigms would assist physicians' clinical decisions.
Kinetics and mechanism of oxidation of riboflavin by periodate in aqueous acidic medium: evidence for the inhibiting effect of iron(II)
The kinetics of oxidation of riboflavin (RFH) by sodium metaperiodate (IO 4 − ) in aqueous acidic medium have been studied. The reaction showed first-order dependence on both reactants and inverse dependence on [H + ] over the pH range 1.4–2.6. The deprotonated form of riboflavin was found to be more reactive than its conjugate acid, (RFH 2 + ). The polymerization of acrylonitrile provided evidence for an inner-sphere mechanism involving iodine(VI) free radicals. The main oxidation products were identified by TLC and mass spectra as lumichrome and 1-acetylglycerol. The effect of iron(II) on the rate of oxidation was studied over the range (0.96–6.0) × 10 −6  mol dm −3 , and the rate was found to decrease with [Fe 2+ ] over the range studied.