Sign in to use this feature.

Years

Between: -

Subjects

remove_circle_outline
remove_circle_outline
remove_circle_outline

Journals

Article Types

Countries / Regions

Search Results (9)

Search Parameters:
Authors = Gancho Kostov ORCID = 0000-0001-5137-6903

Order results
Result details
Results per page
Select all
Export citation of selected articles as:
16 pages, 462 KiB  
Review
Artificial Intelligence-Augmented Advancements in the Diagnostic Challenges Within Renal Cell Carcinoma
by Mladen Doykov, Stanislav Valkanov, Usman Khalid, Jasmin Gurung, Gancho Kostov, Bozhidar Hristov, Petar Uchikov, Maria Kraeva, Krasimir Kraev, Daniel Doykov, Katya Doykova, Siyana Valova, Lyubomir Chervenkov and Stefan Konsulov
J. Clin. Med. 2025, 14(7), 2272; https://doi.org/10.3390/jcm14072272 - 26 Mar 2025
Cited by 1 | Viewed by 1157
Abstract
Background: Advancements in artificial intelligence (AI) diagnostics for renal cell carcinoma (RCC) provide valuable information for classification and subtyping, which improve treatment options and patient care. RCC diagnoses are most commonly incidental due to a lack of specific characterizations of subtypes, often leading [...] Read more.
Background: Advancements in artificial intelligence (AI) diagnostics for renal cell carcinoma (RCC) provide valuable information for classification and subtyping, which improve treatment options and patient care. RCC diagnoses are most commonly incidental due to a lack of specific characterizations of subtypes, often leading to overtreatment. Accurate diagnosis also allows for personalized patient management. Different diagnostic methods, such as histopathology, multi-omics, imaging, and perioperative diagnostics, show a lot of promise for AI. Objective: This literature review focuses on developments in RCC diagnostics and their outcomes, efficacy, and accuracy in classification. Method: We conducted a non-systematic review of the published literature to explore advancements in the diagnostics of RCC. The PubMed and Google Scholar databases were reviewed to extract relevant information. The literature shows that AI can help distinguish RCC from other kidney lesions and track tumor growth. The integration of radiomic features with clinical metadata further enhances the results. This enables clinicians to implement personalized treatment plans. The application of artificial intelligence in perioperative diagnostics enhances decision-making, improves patient safety, mitigates intraoperative complications, and accelerates recovery. Alongside the advancements in AI-assisted diagnostics, there are problems that need to be addressed, including selection bias, demand for larger and diverse datasets, and reliable validation. Conclusions: Despite the challenges, using AI to help with RCC diagnosis could lead to better patient outcomes, a new standard of care for RCC patients, and more personalized cancer management for each patient. Full article
(This article belongs to the Special Issue Clinical Advances in Artificial Intelligence in Urology)
Show Figures

Figure 1

15 pages, 258 KiB  
Review
Artificial Intelligence Algorithms and Their Current Role in the Identification and Comparison of Gleason Patterns in Prostate Cancer Histopathology: A Comprehensive Review
by Usman Khalid, Jasmin Gurung, Mladen Doykov, Gancho Kostov, Bozhidar Hristov, Petar Uchikov, Maria Kraeva, Krasimir Kraev, Daniel Doykov, Katya Doykova, Siyana Valova, Lyubomir Chervenkov, Eduard Tilkiyan and Krasimira Eneva
Diagnostics 2024, 14(19), 2127; https://doi.org/10.3390/diagnostics14192127 - 25 Sep 2024
Cited by 1 | Viewed by 1840
Abstract
The development of the Gleason grading system has proven to be an irreplaceable tool in prostate cancer diagnostics within urology. Despite the advancements and developments in diagnostics, there remains a discrepancy in the grading process among even the most experienced pathologists. AI algorithms [...] Read more.
The development of the Gleason grading system has proven to be an irreplaceable tool in prostate cancer diagnostics within urology. Despite the advancements and developments in diagnostics, there remains a discrepancy in the grading process among even the most experienced pathologists. AI algorithms have demonstrated potential in detecting cancer and assigning Gleason grades, offering a solution to the issue of significant variability among pathologists’ evaluations. Our paper explores the evolving role of AI in prostate cancer histopathology, with a key focus on outcomes and the reliability of various AI algorithms for Gleason pattern assessment. We conducted a non-systematic review of the published literature to examine the role of artificial intelligence in Gleason pattern diagnostics. The PubMed and Google Scholar databases were searched to gather pertinent information about recent advancements in artificial intelligence and their impact on Gleason patterns. We found that AI algorithms are increasingly being used to identify Gleason patterns in prostate cancer, with recent studies showing promising advancements that surpass traditional diagnostic methods. These findings highlight AI’s potential to be integrated into clinical practice, enhancing pathologists’ workflows and improving patient outcomes. The inter-observer variability in Gleason grading has seen an improvement in efficiency with the implementation of AI. Pathologists using AI have reported successful outcomes, demonstrating its effectiveness as a supplementary tool. While some refinements are still needed before AI can be fully implemented in clinical practice, its positive impact is anticipated soon. Full article
(This article belongs to the Section Machine Learning and Artificial Intelligence in Diagnostics)
19 pages, 6812 KiB  
Article
Interventional Treatment of Malignant Biliary Obstruction: Is It Time to Change the Paradigm?
by Bozhidar Hristov, Daniel Doykov, Vladimir Andonov, Mladen Doykov, Krasimir Kraev, Petar Uchikov, Rosen Dimov, Gancho Kostov, Siyana Valova, Katya Doykova, Dzhevdet Chakarov and Milena Sandeva
Gastroenterol. Insights 2024, 15(2), 266-284; https://doi.org/10.3390/gastroent15020020 - 8 Apr 2024
Cited by 1 | Viewed by 2342
Abstract
Introduction. Biliary obstruction is a common manifestation of biliopancreatic malignancies, and its relief is an essential part of the treatment algorithm. Currently, there are three techniques to manage malignant biliary obstruction—endoscopic retrograde cholangiopancreatography (ERCP), percutaneous transhepatic biliary drainage (PTBD), and endoscopic ultrasound-guided biliary [...] Read more.
Introduction. Biliary obstruction is a common manifestation of biliopancreatic malignancies, and its relief is an essential part of the treatment algorithm. Currently, there are three techniques to manage malignant biliary obstruction—endoscopic retrograde cholangiopancreatography (ERCP), percutaneous transhepatic biliary drainage (PTBD), and endoscopic ultrasound-guided biliary drainage (EUS-BD). ERCP has been adopted as a first-line treatment modality but EUS-BD is gradually emerging as a viable alternative. The aim of the current article is to assess the clinical outcomes of the three nonsurgical biliary drainage procedures. Materials and methods. A total of 102 consecutive patients with unresectable biliopancreatic malignancy inducing biliary obstruction and subjected to palliative treatment by means of ERCP, EUS-BD, or PTBD were retrospectively included in the study. Results. No difference in clinical and technical success of the procedures was found: ERCP—97.2% technical; 88.9% clinical; PTBD—94.4% technical, 72.2% clinical; EUS-BD—90% technical; 83.3% clinical. Adverse events (AEs) and reinterventions were significantly more common in PTBD (38.9% and 52.8%) and ERCP (27.9% and 25%) compared to EUS-BD (10% and 3.3%). Total duration of hospital stay and number of hospitalizations were lower in the EUS-BD compared to PTBD and ERCP groups. Conclusions. In the presence of adequate expertise, EUS-BD may be superior to PTBD and ERCP in achieving and sustaining biliary drainage in the setting of unresectable malignancy. Full article
(This article belongs to the Section Biliary Content)
Show Figures

Figure 1

12 pages, 2833 KiB  
Case Report
Hepatico-Duodenal Fistula Following Iatrogenic Strasberg Type E4 Bile Duct Injury: A Case Report
by Bozhidar Hristov, Daniel Doykov, Desislav Stanchev, Krasimir Kraev, Petar Uchikov, Gancho Kostov, Siyana Valova, Eduard Tilkiyan, Katya Doykova and Mladen Doykov
Medicina 2023, 59(9), 1621; https://doi.org/10.3390/medicina59091621 - 7 Sep 2023
Cited by 3 | Viewed by 2506
Abstract
Introduction: Gallstone disease (GSD) is among the most common disorders worldwide. Gallstones are established in up to 15% of the general population. Laparoscopic cholecystectomy (LC) has become the “gold standard” for treatment of GSD but is associated with a higher rate of certain [...] Read more.
Introduction: Gallstone disease (GSD) is among the most common disorders worldwide. Gallstones are established in up to 15% of the general population. Laparoscopic cholecystectomy (LC) has become the “gold standard” for treatment of GSD but is associated with a higher rate of certain complications, namely, bile duct injury (BDI). Biliary fistulas (BF) are a common presentation of BDI (44.1% of all patients); however, they are mainly external. Post-cholecystectomy internal BF are exceedingly rare. Case report: a 33-year Caucasian female was admitted with suspected BDI after LC. Strasberg type E4 BDI was established on endoscopic retrograde cholangiopancreatography (ERCP). Urgent laparotomy established biliary peritonitis. Delayed surgical reconstruction was planned and temporary external biliary drains were positioned in the right and left hepatic ducts. During follow-up, displacement of the drains occurred with subsequent evacuation of bile through the external fistula, which resolved spontaneously, without clinical and biochemical evidence of biliary obstruction or cholangitis. ERCP established bilio-duodenal fistula between the left hepatic duct (LHD) and duodenum, with a stricture at the level of the LHD. Endoscopic management was chosen with staged dilation and stenting of the fistulous tract over 18 months until fistula maturation and stricture resolution. One year after stent extraction, the patient remains symptom free. Discussion: Management of post-cholecystectomy BDI is challenging. The optimal approach is determined by the level and extent of ductal lesion defined according to different classifications (Strasberg, Bismuth, Hannover). Type E BDI are managed mainly surgically with a delayed surgical approach generally deemed preferable. Only three cases of choledocho-duodenal fistulas following LC BDI currently exist in the literature. Management is controversial, with expectant approach, surgical treatment (biliary reconstruction), or liver transplantation being described. Endoscopic treatment has not been described; however, in the current paper, it proved to be successful. More reports or larger case series are needed to confirm its applicability and effectiveness, especially in the long term. Full article
(This article belongs to the Special Issue Advances in Cholecystitis and Cholecystectomy)
Show Figures

Figure 1

10 pages, 1143 KiB  
Case Report
Cholangioscopy-Assisted Laser Lithotripsy for Treatment of Postcholecystectomy Mirizzi Syndrome: Case Series
by Bozhidar Hristov, Daniel Doykov, Vladimir Andonov, Deyan Radev, Krasimir Kraev, Petar Uchikov, Gancho Kostov, Siyana Valova, Eduard Tilkiyan and Katya Doykova
Gastroenterol. Insights 2023, 14(1), 121-130; https://doi.org/10.3390/gastroent14010009 - 6 Mar 2023
Cited by 1 | Viewed by 6355
Abstract
Introduction. Mirizzi syndrome (MS) represents a rare clinical entity caused by impaction of one or multiple stones in the infundibulum of the gall bladder or the cystic duct resulting in partial or complete obstruction of the common hepatic or common bile duct (CBD). [...] Read more.
Introduction. Mirizzi syndrome (MS) represents a rare clinical entity caused by impaction of one or multiple stones in the infundibulum of the gall bladder or the cystic duct resulting in partial or complete obstruction of the common hepatic or common bile duct (CBD). Though described more than a century ago, MS is still one of the most challenging diseases in the spectrum of biliary pathology. In recent years, endoscopic treatment has become an increasingly popular treatment modality. Patients and methods. Three consecutive patients subjected to cholangioscopy-assisted laser lithotripsy (CA-LL) for postocholecystectomy MS (pMS) were retrospectively evaluated. Case reports. Successful clearance of the cystic duct was achieved in all patients in one or two sessions. One complication in the form of mild cholangitis was observed. Clinical success was 100%. Discussion. According to current research, CA-LL achieves a high rate of ductal clearance and acceptable complication rate in patients with pMS. A 250 µm laser fiber seems to be the optimal choice for CA-LL. Our results suggest that procedure duration is closely associated to the stone size and possibly to the operator experience. In our opinion, upon obtainment of successful ductal clearance and drainage, prophylactic stenting does not improve clinical outcome. Conclusions. Our results demonstrate that CA-LL is a safe and effective treatment for pMS. Full article
(This article belongs to the Section Biliary Content)
Show Figures

Figure 1

9 pages, 3047 KiB  
Case Report
Clinical Outcomes of EUS-Guided Choledochoduodenostomy for Biliary Drainage in Unresectable Pancreatic Cancer: A Case Series
by Bozhidar Hristov, Deyan Radev, Petar Uchikov, Gancho Kostov, Mladen Doykov, Siyana Valova and Eduard Tilkiyan
Medicina 2023, 59(2), 351; https://doi.org/10.3390/medicina59020351 - 13 Feb 2023
Cited by 6 | Viewed by 3129
Abstract
Introduction. Pancreatic ductal adenocarcinoma (PDA) is associated with poor prognosis and 98% loss-of-life expectancy. 80% of patients with PDA are unfit for radical surgery. In those cases, emphasis is set on management of cancer-related symptoms, among which obstructive jaundice is most common. Endoscopic [...] Read more.
Introduction. Pancreatic ductal adenocarcinoma (PDA) is associated with poor prognosis and 98% loss-of-life expectancy. 80% of patients with PDA are unfit for radical surgery. In those cases, emphasis is set on management of cancer-related symptoms, among which obstructive jaundice is most common. Endoscopic ultrasound-guided biliary drainage (EUS-BD) emerges as a valid alternative to the well-accepted methods for treatment of biliary obstruction. Patient Selection. Five consecutive patients with unresectable pancreatic malignancy, were subjected to EUS-BD, particularly EUS-guided choledochoduodenostomy (EUS-CDS). Ethics. Oral and written informed consent was obtained in all cases prior procedure. Technique. EUS-guided puncture of the common bile duct was performed, followed by advancement of a guidewire to the intrahepatic bile ducts. After dilation of the fistulous tract with a cystotome, a fully covered self-expandable metal stent was inserted below the hepatic confluence and extending at least 3 cm in the duodenum. Technical and clinical success was achieved in four patients without adverse events. In one patient procedure failed due to dislocation of the guidewire, with consequent biliary leakage requiring urgent surgery. Recovery was uneventful with no further clinical sequelae and there was no mortality associated with procedure. Discussion. Introduced in 2001, EUS-guided biliary drainage has become an accepted option for treatment of obstructive jaundice. According to recent guidelines published by European Society of Gastrointestinal Endoscopy (ESGE) in 2022, EUS-CDS is a preferred modality to percutaneous transhepatic biliary drainage (PTBD) and surgery in patients with failed ERCP, with comparable efficiency and better safety profile, which is supported by our experience with the procedure. Conclusions. Our case series suggests that EUS-CDS is an excellent option for palliative management of malignant distal biliary obstruction, emphasizes on the importance of adequate technique and experience for the technical success, and urges the need for future research on establishing the best choice for guidewire and dilation device. Full article
(This article belongs to the Special Issue Acute and Chronic Pancreatitis, Pancreatic Malignancies)
Show Figures

Figure 1

8 pages, 309 KiB  
Article
Prophylactic Central Neck Lymph Node Dissection Adds No Short-Term Benefit to Total Thyroidectomy for Differentiated Thyroid Cancer
by Rosen Dimov, Gancho Kostov, Mladen Doykov, Luboslav Dimov, Boyan Nonchev, Rositsa Dimova and Bozhidar Hristov
Medicina 2023, 59(2), 239; https://doi.org/10.3390/medicina59020239 - 27 Jan 2023
Cited by 1 | Viewed by 2562
Abstract
Background and Objectives: To answer the research question: “Is prophylactic central neck lymph node dissection (pCNLD) beneficial among differentiated thyroid carcinoma (DTC) patients?” Materials and Methods: This was a retrospective cohort study enrolling DTC patients treated at the University Hospital Kaspela, [...] Read more.
Background and Objectives: To answer the research question: “Is prophylactic central neck lymph node dissection (pCNLD) beneficial among differentiated thyroid carcinoma (DTC) patients?” Materials and Methods: This was a retrospective cohort study enrolling DTC patients treated at the University Hospital Kaspela, Bulgaria, from 30 January 2019 to October 2021. The predictor variable was presence of pCNLD (total thyroidectomy with vs. without pCNLD). The main outcome variables were postoperative complications (i.e., vocal cord paralysis, hypoparathyroidism, postoperative bleeding, and adjacent organ injury) and recurrence parameters. Appropriate statistics were computed with the significant level at p ≤ 0.05. Results: During the study period, 300 DTC patients (59.7% with pCNLD; 79.3% females) with an average age of 52 ± 2.8 years were treated. The mean follow-up period of the entire cohort was 45.8 ± 19.1 months. On bivariate analyses, TT with pCNLD, when compared to TT alone, required longer surgical time (mean difference: 9.4 min), caused nearly similar complications (except transient hypothyroidism: p = 0.04; relative risk, 1.32; 95% confidence interval, 1.0 to 1.73), and no significantly different recurrence events, time to recurrence, and recurrent sites. The benefit–risk analyses using the number needed to treat and to harm (NNT; NNH) also confirmed that TT plus pCNLD was not very beneficial in DTC management. Conclusion: The results of this study refute the benefit of pCNLD in DTC patient care with TT. Further well-designed studies in a larger cohort with a longer follow-up period are required to confirm this conclusion. Full article
Show Figures

Graphical abstract

10 pages, 6070 KiB  
Article
Evaluation of Liver Stiffness Measurement by Means of 2D-SWE for the Diagnosis of Esophageal Varices
by Bozhidar Hristov, Vladimir Andonov, Daniel Doykov, Katya Doykova, Siyana Valova, Emiliya Nacheva-Georgieva, Petar Uchikov, Gancho Kostov, Mladen Doykov and Eduard Tilkian
Diagnostics 2023, 13(3), 356; https://doi.org/10.3390/diagnostics13030356 - 18 Jan 2023
Cited by 6 | Viewed by 1981
Abstract
Portal hypertension (PH) and esophageal varices (EVs) are a matter of extensive research. According to current Baveno VII guidelines, in patients with compensated advanced chronic liver disease (cACLD), liver stiffness measurement (LSM) < 15 kPa and PLT count > 150 × 109 [...] Read more.
Portal hypertension (PH) and esophageal varices (EVs) are a matter of extensive research. According to current Baveno VII guidelines, in patients with compensated advanced chronic liver disease (cACLD), liver stiffness measurement (LSM) < 15 kPa and PLT count > 150 × 109/L, upper endoscopy (UE) is not mandatory, and the emphasis should be set on non-invasive methods for evaluation of clinically significant portal hypertension (CSPH). The aim of this study is to establish whether liver stiffness (LS) measured by 2D-SWE could be used as a predictor for the presence and severity of EVs in cirrhotic patients. In total, 86 patients of whom 32 with compensated liver cirrhosis (cLC) and 54 with decompensated liver cirrhosis (dLC) were examined in the Gastroenterology clinic of University hospital “Kaspela”, Plovdiv, Bulgaria. Each patient underwent LS assessment by 2D-SWE and EVs grading by UE. EVs were detected in 47 (54.7%) patients, 23 (49%) of them were stage 4-high-risk EVs (HREV). The cut-off value for LS that differentiates HREV from the rest was set at 2.49 m/s with 100% sensitivity and 100% specificity (AUC 1.000, CI 0.925). Conclusions: 2D-SWE can be used as a non-invasive method in the assessment of only high-grade esophageal varices. For the other grades, upper endoscopy remains the method of choice. Full article
(This article belongs to the Special Issue Ultrasound Imaging in Digestive and Kidney Diseases)
Show Figures

Figure 1

12 pages, 2049 KiB  
Article
Factors Affecting Residual Stone Rate, Operative Duration, and Complications in Patients Undergoing Minimally Invasive Percutaneous Nephrolithotomy
by Mladen Doykov, Gancho Kostov and Katya Doykova
Medicina 2022, 58(3), 422; https://doi.org/10.3390/medicina58030422 - 13 Mar 2022
Cited by 10 | Viewed by 3332
Abstract
Background and objectives: Although minimally invasive percutaneous nephrolithotomy (MPCNL) has demonstrated its efficacy, complete stone clearance was not always achieved, necessitating a second procedure. The purpose of this study was to evaluate factors associated with residual stone rate, operative duration, complications, and [...] Read more.
Background and objectives: Although minimally invasive percutaneous nephrolithotomy (MPCNL) has demonstrated its efficacy, complete stone clearance was not always achieved, necessitating a second procedure. The purpose of this study was to evaluate factors associated with residual stone rate, operative duration, complications, and hospital stay, in order to develop algorithms for pre-operative prognosis and planning. Materials and Methods: This retrospective study involved 163 Bulgarian patients who underwent MPCNL with Holmium: YAG lithotripsy for the treatment of kidney stones. Patients were considered stone-free if no visible fragments (<3 mm) were found on nephroscopy at the end of the procedure, as well as on postoperative X-ray and abdominal ultrasound on the first postoperative day. Results: Immediate postoperative stone-free outcome was attained for 83.43% of the patients (136/163). Residuals were associated with staghorn stones (OR = 72.48, 95% CI: 5.76 to 91.81); stones in two locations (OR = 21.91, 95% CI: 4.15 to 137.56); larger stone size (OR = 1.12, 95% CI: 1.006 to 1.25); and higher density (OR = 1.03, 95% CI:1.005 to 1.06). The overall categorization accuracy for these factors was 93.80%, AUC = 0.971 (95% CI: 0.932 to 0.991), 89.71% sensitivity, and 96.30% specificity. Predictors of prolonged operative duration were staghorn stones and volume, R-square (adj.) = 39.00%, p < 0.001. Longer hospitalization was predicted for patients with hydronephrosis and staghorn stones, R-square (adj.) = 6.82%, p = 0.003. Post-operative complications were rare, predominantly of Clavien-Dindo Grade 1, and were more frequent in patients with hydronephrosis. We did not find a link between their occurrence and the outcome of MPCNL. Conclusions: Staghorn stones and stones in more than one location showed the strongest association with residual stone rate. Staghorn stones and larger volume were linked with a longer operative duration. Hydronephrosis increased the risk of complications and longer hospitalization. Full article
(This article belongs to the Section Surgery)
Show Figures

Figure 1

Back to TopTop