Applied physiology: gut microbiota and antimicrobial therapy

The gut microbiota plays an important role in maintaining human health and in the pathogenesis of several diseases. Antibiotics are among the most commonly prescribed drugs and have a significant impact on the structure and function of the gut microbiota. The understanding that a healthy gut microbiota prevents the development of many diseases has also led to its consideration as a potential therapeutic target. At the same time, any factor that alters the gut microbiota becomes important in this approach. Exercise and antibacterial therapy have a direct effect on the microbiota. The review reflects the current state of publications on the mechanisms of intestinal bacterial involvement in the pathogenesis of cardiovascular, metabolic, and neurodegenerative diseases. The physiological mechanisms of the influence of physical activity on the composition of the gut microbiota are considered. The mechanisms of the common interface between exercise and antibacterial therapy will be considered using the example of several socially important diseases. The aim of the study is to show the physiological relationship between the effects of exercise and antibiotics on the gut microbiota.

[Comparative immunohistochemistry study of different antibodies clones for detection of breast cancer markers (estrogen receptor, progesterone receptor, HER2/neu, Ki-67)]

OBJECTIVE

A comparative study of detection of breast cancer markers (estrogen receptors, progesterone receptors, HER2/neu, Ki-67) by immunohistochemical method with antibodies produced by PrimeBioMed (Russia) and antibodies produced by Roche Ventana (USA).

MATERIAL AND METHODS

Surgical specimens and biopsies from 37 patients with invasive breast cancer were used. Sections were stained with antibodies of clones ER SP1 and GM030, PR 1E2 and PBM-5B8, HER2/neu 4B5 and PBM-46A6, Ki-67 30-9 and GM010.

RESULTS

There was a high positive and significant correlation between the immunohistochemistry results and antibodies of the clones ER-SP1 and GM030, PR1E2 and PBM-5B8, HER2/neu4B5 and PBM-46A6, Ki-67 30-9 and GM010.

CONCLUSION

The study showed the possibility of using antibodies of clones GM030, HER2/neu 4B5, PBM-46A6, GM010 (PrimeBioMed) on the Ventana Bench Marck Ultra automatic immunostainer using the detection system UltraView Universal DAB Detection Kit.

[Features of encrustation of ureteral stents in patients with calcium oxalate and urinary acid stones]

INTRODUCTION

Stent encrustation is one of the most difficult problems that can lead to difficulties in stent removal, while ureteral obstruction can lead to renal failure. Despite the search for various preventive measures, it still remains unresolved.

AIM

To study the effect of Blemaren on stent encrustation in patients with calcium-containing and uric acid stones after ureteroscopy with lithotripsy.

MATERIALS AND METHODS

A total of 60 patients with ureteral stones who underwent ureteroscopy with lithotripsy in A.V. Vishnevsky National Medical Research Center of Surgery from January to August 2022, were included in the study. In all cases ureteral stents 6 Ch were placed at the end of the procedure. Patients with uric acid and calcium oxalate stones (n=48) were randomized into two groups: in the main group (n=20), they were prescribed Blemaren up to the stent removal. In the control group (n=28), patients did not receive additional therapy. To determine the severity of incrustation, we used our own classification, where the percentage of lithogenic deposits relative to the lumen of the stent was calculated. Visual assessment and microscopic examination of the removed stents were performed on days 30+/-4.1 and 60+/-7.3.

RESULTS

In patients of both groups, the severity of encrustation on the 30th day after stent placement was low (up to 30%). There were no significant differences between the groups (p=0.421). The main changes were detected 60 days after stent placement. Microscopic study revealed significant differences between two groups. In patients who did not receive Blemaren, microscopic signs of encrustation of the proximal curl of the stent occurred 2.5 times more often than in the main group (p=0.001).

CONCLUSIONS

1. The number of encrusted stents in patients with calcium oxalate and uric acid stones who did not receive Blemaren significantly increases after two months. 2. Upper urinary tract drainage with a stent for a period of more than 2 months is possible if clinically necessary, however, preventive measures to reduce the risk of encrustation should be applied.

Clostridioides difficile infection in patients with nonalcoholic fatty liver disease-current status

Nonalcoholic fatty liver disease (NAFLD) is the most common chronic liver disease, leading to fibrosis, cirrhosis and hepatocellular carcinoma and also associated with increased cardiovascular disease mortality. The pathogenesis of NAFLD is not fully understood, although NAFLD is thought to be a hepatic form of metabolic syndrome. There is an increasing understanding of the role of microbiota disturbances in NAFLD pathogenesis, and as with many other conditions affecting the microbiota, NAFLD may be a novel risk factor for Clostridioides difficile (C. difficile) colonization (CDC) and C. difficile infection (CDI). CDI is an emerging nosocomial disease, and community-acquired cases of infection are growing, probably due to an increase in CDC rates. The association of NAFLD with CDI has been shown in only 4 studies to date, three of which included less than 1000 patients, although the frequency of NAFLD in these studies was observed in almost 20% of the total patient cohort. These data revealed that NAFLD is a risk factor for CDI development and, moreover, is a risk factor for intestinal complications of CDI. More studies are needed to investigate this association and move forward CDC and CDI screening efforts for this group of patients.

[Prognostic significance of PD-L1 expression as a potential predictor of survival in gastric cancer]

BACKGROUND

Currently, PD-L1 expression in patients with tumors of various localizations is being actively studied. Studies on the expression of PD-L1 detected by clones SP142 and SP263 in gastric cancer (for the drugs atezolizumab and durvalumab, respectively) are rare in the literature. The prognostic role of PD-L1 expression in patients who were not treated with immune checkpoint inhibitors has also not been investigated.

OBJECTIVE

To determine the expression level of PD-L1 (clones SP263 and SP142, Roche Ventana) in gastric cancer specimens and evaluate its effect on overall survival in patients who did not receive adjuvant therapy with immune checkpoint inhibitors.

MATERIAL AND METHODS

The study included 131 patients with a verified diagnosis of gastric cancer. The material obtained from 127 patients was stained with antibodies to PD-L1 SP263, and from 126 patients - with antibodies to PD-L1 SP142. A multivariate Cox regression model with Wald's step-by-step exclusion algorithm was used to evaluate predictors of survival.

RESULTS

The total five-year survival rate of patients in the PD-L1-negative tumor group was significantly lower than the total five-year survival rate of patients in the PD-L1-positive tumor group, which was 50.0% and 40.0% also for both clones (p=0.027). An increase in the expression of PD-L1 clone SP263, determined by both the CPS and TPS method, reduces the chances of death by 1.35 times (p=0.02) and 1.61 times (p=0.004), respectively. An increase in the expression of PD-L1 clone SP142, determined by the CPS method, reduces the chances of death by 1.54 times (p=0.005).

CONCLUSION

The survival rate of patients in the group of PD-L1-positive tumors is significantly higher than in patients in the group of PD-L1-negative tumors. Elevated PD-L1 expression, as assessed by the SP263 and SP142 clones, is an important prognostic marker that predicts a higher chance of overall survival for patients, even though these patients are not receiving immune checkpoint inhibitors adjuvant therapy.

ALDH3A2, ODF2, QSOX2, and MicroRNA-503-5p Expression to Forecast Recurrence in TMPRSS2-ERG-Positive Prostate Cancer

Following radical surgery, patients may suffer a relapse. It is important to identify such patients so that therapy tactics can be modified appropriately. Existing stratification schemes do not display the probability of recurrence with enough precision since locally advanced prostate cancer (PCa) is classified as high-risk but is not ranked in greater detail. Between 40 and 50% of PCa cases belong to the TMPRSS2-ERG subtype that is a sufficiently homogeneous group for high-precision prognostic marker search to be possible. This study includes two independent cohorts and is based on high throughput sequencing and qPCR data. As a result, we have been able to suggest a perspective-trained model involving a deep neural network based on both qPCR data for mRNA and miRNA and clinicopathological criteria that can be used for recurrence risk forecasts in patients with TMPRSS2-ERG-positive, locally advanced PCa (the model uses ALDH3A2 + ODF2 + QSOX2 + hsa-miR-503-5p + ISUP + pT, with an AUC = 0.944). In addition to the prognostic model’s use of identified differentially expressed genes and miRNAs, miRNA–target pairs were found that correlate with the prognosis and can be presented as an interactome network.

[Study of gastric adenocarcinomas association with the Epstein-Barr virus-encoded small RNAs]

OBJECTIVE

Assessment of the incidence of EBV-associated gastric adenocarcinomas in a sample of Russian patients, as well as clarification of the clinical and morphological characteristics and median survival of patients with EBV-associated gastric cancer.

MATERIAL AND METHODS

We used samples of surgical material from 282 patients with a verified diagnosis of gastric cancer. Each sample was stained by in situ hybridization using primers for the Epstein-Barr virus-encoded small RNAs (EBER). The results obtained were compared with the main clinical and morphological characteristics of gastric cancer.

RESULTS

The detection rate of EBV-associated gastric adenocarcinoma in our sample was 9.57%. EBER-positive tumors much more often (p=0.021) belong to the intermediate type according to the P. Lauren classification (66.67%) in comparison with EBER-negative tumors (38.82%). EBER-positive tumors significantly more often (p=0.035) belong to high-grade tumors - 75.00% in comparison with EBER-negative tumors (52.13%). The overall median survival of all patients with EBER-positive tumors (53.5 months) was higher compared to the overall median survival of all patients with EBER-negative tumors - 36.5 months (p=0.5379). The median survival of patients with EBER-positive stage III tumors (30.0 months) was also higher compared to that for patients with EBER-negative tumors - 20.0 months (p=0.5622). It was found that a single EBER status is not a significant prognostic factor (HR=1.0143; CI: 0.9897-1.0196).

CONCLUSION

Separately taken EBER-status is not a significant independent prognostic factor and can be considered only in conjunction with the «classical» clinical and morphological characteristics, primarily with the stage of the tumor process, since it is they that determine the prognostic properties of the tumor.

[Mortality in acute appendicitis in Russia]

OBJECTIVE

To analyze the causes of mortality in patients with acute appendicitis in Russia.

MATERIAL AND METHODS

We retrospectively studied mortality in patients with acute appendicitis in the Russian Federation in 2020. We surveyed the hospitals with mortality reported in the electronic database of annual reports to the chief surgeon of the Ministry of Health of the Russian Federation.

RESULTS

There were 259 deaths among 150.393 patients with acute appendicitis aged ≥18 years (in-hospital mortality 0.17%). We obtained data about 95.8% (n=248) of lethal cases including 86.3% (n=214) complicated and 13.7% (n=34) uncomplicated forms of disease. Two patients died without surgery (0.8%). Among the deceased, 58.2% (n=145) were men and 41.8% (n=103) were women. Mean patient age was 66.2 years [0.95% CI 64.2-68.1]. The main cause of death in complicated appendicitis was late presentation (after 4.9 days [0.95% CI 4.3-5.4]) that resulted peritonitis and sepsis in 71.5% (n=153) of patients. Cardiovascular diseases were noted in 23.4% (n=50) of cases. A new coronavirus infection was detected in 7.0% (n=15) of patients. However, COVID-19 as a direct cause of death was recognized in 2.8% (n=6) of cases. Other reasons accounted for 2.3% (n=5). In uncomplicated appendicitis, cardiovascular diseases were the main cause of mortality (73.5%, n=25). Peritonitis and sepsis were found in 11.8% (n=4) of cases, COVID-19 - in 5.9% (n=2). Other causes accounted for 8.8% (n=3). Diagnostic, tactical, technical problems and their combination were revealed in 54.4% of lethal outcomes.

CONCLUSION

Mortality from acute appendicitis in the Russian Federation is low, comparable with international data, and mainly associated with delayed treatment and complicated course of disease. However, the impact of diagnostic, tactical and technical errors on the outcome of acute appendicitis is significant.

[PD-L1 expression in EBV-associated gastric carcinomas]

OBJECTIVE

Assessment of the incidence of PD-L1 expression in EBV-associated gastric adenocarcinomas, as well as clarification of the clinical and morphological characteristics and median survival of patients with PD-L1-positive EBV-associated gastric cancer.

MATERIAL AND METHODS

Samples of surgical material from 127 patients with stomach cancer were studied. Each sample was stained by in situ hybridization using primers for the Epstein-Barr virus-encoded small RNAs (EBER). Expression of PD-L1 was assessed immunohistochemically (PD-L1 SP263, PD-L1 SP142). The results obtained were compared with the main clinical and morphological characteristics of gastric cancer and median survival of patients.

RESULTS

The detection rate of PD-L1 SP263 and PD-L1 SP142 in EBV-associated gastric adenocarcinoma in our sample was 100% and 76.9% respectively, thus, PD-L1 expression (SP263, SP142) is significantly more frequently detected in EBV-associated gastric carcinomas. It was found that patients with positive expression of PD-L1 in EBV-associated gastric carcinomas are younger (mean age 56.3 years for SP263 and 55.6 years for SP142), belonging to male gender. In addition, this group is dominated by proximal localization of tumors, ulcerative form of growth, tubular histological type, intermediate subtype according to P. Lauren. These characteristics do not depend on the antibody clone: positive expression of SP142 and SP 263 was detected in the same patients with a few exceptions. The overall median survival of patients with positive PD-L1 status SP263 in EBV-associated gastric carcinomas was 35 months, for patients with positive PD-L1 status SP142 - 25 months. Median survival of SP142 PD-L1 positive patients is higher than overall median survival of PD-L1 negative patients in EBV-associated gastric carcinomas. It was found that PD-L1 status in EBV-associated gastric cancer is not a significant prognostic factor.

CONCLUSION

A single PD-L1 status does not significantly affect the prognosis in patients with gastric cancer, including those in the group of EBV-associated carcinomas, and can only be considered in conjunction with 'classic' clinical and morphological characteristics, primarily with the stage of the tumor process, since they determine the prognostic properties of the tumor.

Rare primary mature teratoma of the liver: A case report

BACKGROUND

Primary liver teratoma is an extremely rare tumor usually affecting children under the age of 3 years. Specific signs of teratoma on ultrasound, computed tomography (CT) or magnetic resonance imaging are lacking, which makes morphology the only diagnostic tool. Misdiagnosis of a mature teratoma may lead to excessive liver resection, whereas misdiagnosis of an immature teratoma may result in spread, causing a life-threatening condition. Consequently, a careful tumor examination is important, and the rarest types of tumors must be accounted for.

CASE SUMMARY

We describe a 52 years old female who presented with a solid mass in the left liver lobe. Contrast-enhanced CT and magnetic resonance imaging (MRI) revealed a round, heterogeneous lesion containing a number of fluid areas and areas of calcification in the middle, and the provisional diagnosis was cholangiocarcinoma. The patient underwent resection of liver segment I. Immunohistochemistry analysis of the resected lesion indicated thyroid follicular epithelium; however, the thyroid gland was intact. 10 years prior to presentation the patient underwent a surgery due to mature teratoma of the right ovary, nevertheless the tumor was benign and could not spread to the liver, in addition teratoma of the liver was also benign. This led to the final diagnosis of primary mature liver teratoma.

CONCLUSION

Primary hepatic teratoma, including heterotopia of the thyroid gland in the liver, is an extremely rare condition in adults that needs to be considered in the differential diagnosis of solid-cystic neoplasms in the liver and cholangiocarcinoma. This case adds to the limited literature on the patient presentation, clinical workup and management of liver teratomas.

[Effect of morphological state of pancreatic parenchyma on the long-term outcome of surgery for chronic pancreatitis]

OBJECTIVE

To determine the effect of baseline morphological state of the pancreas on the long-term outcomes of duodenum-preserving pancreatic head resection (DPPHR).

MATERIAL AND METHODS

The study included 104 patients with chronic pancreatitis (CP), who underwent DPPHR in 2014-2019. Pain syndrome, exocrine and endocrine pancreatic insufficiency and quality of life (QoL) were assessed in long-term postoperative period. Patients were stratified depending on CT enhancement of pancreatic parenchyma as an indicator of fibrosis and amount of preserved acinar cells in resected pancreatic tissue.

RESULTS. S

Ignificant relief of pain syndrome in long-term period was observed in patients with higher density of pancreatic tissue in venous phase of CT compared to delayed phase. Moreover, these patients needed less additional enzyme intake and had higher QoL. Exocrine insufficiency depended on the number of preserved acinar cells. The percentage of preserved acinar cells also affects the QoL of patients with CP. There were no correlations between endocrine insufficiency and CT-findings, as well as the number of preserved acinar cells.

CONCLUSION

Higher CT-density of pancreatic parenchyma in venous phase indicates a lesser degree of fibrosis. It is a favorable prognostic factor for postoperative pain relief and preservation of exocrine function. The percentage of preserved acinar cells in the resected pancreatic tissue is a reliable predictor of exocrine insufficiency.

[Computed tomography in determining the differentiation of ductal adenocarcinoma of pancreatic head]

OBJECTIVE

To evaluate the features of «hypervascular rim», tumor dimensions and density as prognostic factors of differentiation of pancreatic head adenocarcinoma.

MATERIAL AND METHODS

Pancreatoduodenectomy was performed in 311 patients with pancreatic head adenocarcinoma for the period 2013-2019. A retrospective study included 81 patients who met the following criteria: available data of morphological and immunohistological examination indicating tumor grade from Grade 1 to Grade 3, as well as available preoperative CT images in four phases (native, arterial, portal and delayed). Tumor dimensions, density of the pancreas, adenocarcinoma and abdominal aorta by the phases of contrast enhancement were analyzed in all patients. Moreover, we estimated coefficient of relative enhancement change. Perifocal hypervascular enhancement was assessed in arterial and portal phases. Contrast-enhanced MRI was performed in 15 out of 81 patients. MR images were analyzed regarding a hypervascular rim, and the last one was compared with CT images.

RESULTS

There was no significant difference in density values between different tumor grades. Coefficient of relative enhancement change >1 was observed in 63.64% of highly-differentiated tumors. REC ≤1 was found in 85.11% of tumors grade 2 and 82.6% of tumors grade 3 (p=0.005). According to Chi-square test, there was a correlation between tumor differentiation and hypervascular rim (p=0.03). Moderate and low differentiation was observed in 96.42% of tumors with perifocal enhancement. Hypervascular rim was absent in 81.82% of tumors grade 1. Adenocarcinoma grade 2 was found in 85.71% of cases with unclear perifocal enhancement.

CONCLUSION

Preoperative contrast-enhanced CT is valuable to assume the tumor grade in patients with pancreatic head adenocarcinoma due to assessment of hypervascular rim and REC.

Molecular pathways of liver regeneration: A comprehensive review

The liver is a unique parenchymal organ with a regenerative capacity allowing it to restore up to 70% of its volume. Although knowledge of this phenomenon dates back to Greek mythology (the story of Prometheus), many aspects of liver regeneration are still not understood. A variety of different factors, including inflammatory cytokines, growth factors, and bile acids, promote liver regeneration and control the final size of the organ during typical regeneration, which is performed by mature hepatocytes, and during alternative regeneration, which is performed by recently identified resident stem cells called “hepatic progenitor cells”. Hepatic progenitor cells drive liver regeneration when hepatocytes are unable to restore the liver mass, such as in cases of chronic injury or excessive acute injury. In liver maintenance, the body mass ratio is essential for homeostasis because the liver has numerous functions; therefore, a greater understanding of this process will lead to better control of liver injuries, improved transplantation of small grafts and the discovery of new methods for the treatment of liver diseases. The current review sheds light on the key molecular pathways and cells involved in typical and progenitor-dependent liver mass regeneration after various acute or chronic injuries. Subsequent studies and a better understanding of liver regeneration will lead to the development of new therapeutic methods for liver diseases.

Effect of Silicon Dioxide Nanoparticles on Syrian Hamsters Infected by Opisthorchis felineus: 1H MRS Study of the Brain

In recent years, silicon dioxide nanoparticles have been widely used in medicine and the pharmaceutical industry, however, their effect on the brain has hardly been studied. We assessed the effects of long-term consumption of 5-nm amorphous silicon dioxide nanoparticles (SiO₂-NPs) by Syrian hamsters infected with the trematodes Opisthorchis felineus on the hippocampus and frontal cortex. Spectroscopic determination of brain neurometabolites, performed using a horizontal Magnetic Resonance Imaging system at 11.7 Tesla magnetic field, has shown that the ratio of the excitatory neurotransmitters (glutamate + glutamine + aspartate) to the inhibitory ones (GABA + glycine) was higher in the animals infected with O. felineus. However, pre-consumption of the SiO₂-NPs solution prevented this imbalance. In addition, the protective effect of SiO₂-NPs on the level of myo-inositol and glycine was found. It is concluded that the use of SiO₂-NPs can neutralize the negative effects of infectious factors on the brain.

Mutation Frequency in Main Susceptibility Genes Among Patients With Head and Neck Paragangliomas

Head and neck paragangliomas (HNPGLs) are rare neuroendocrine tumors that have a high degree of heritability and are predominantly associated with mutations in ten genes, such as SDHx, SDHAF2, VHL, RET, NF1, TMEM127, MAX, FH, MEN2, and SLC25A11. Elucidating the mutation prevalence is crucial for the development of genetic testing. In this study, we identified pathogenic/likely pathogenic variants in the main susceptibility genes in 102 Russian patients with HNPGLs (82 carotid and 23 vagal paragangliomas) using whole exome sequencing. Pathogenic/likely pathogenic variants were detected in 43% (44/102) of patients. We identified the following variant distribution of the tested genes: SDHA (1%), SDHB (10%), SDHC (5%), SDHD (24.5%), and RET (5%). SDHD variants were observed in the majority of the patients with bilateral/multiple paragangliomas. Thus, among Russian patients with HNPGLs the most frequently mutated gene was SDHD followed by SDHB, SDHC, RET, and SDHA.

[Massive localized lymphedema of anterior abdominal wall]

Massive localized lymphedema (MLL) is a rare disease observed in people with morbid obesity. MLL is easily confused with soft tissue sarcoma. Therefore, MLL is sometimes called as pseudosarcoma in the literature. MLL was initially described by G. Farshid and S. Weiss in 1998. However, etiology of MLL is still unknown despite certain relationships with injuries, operations and hypothyroidism. Since the term «MLL» was introduced only 20 years ago, there are no reliable statistical data on the prevalence of MLL. According to the World Health Organization data (2016), 13% of the adult world population are obese. Therefore, the risk of MLL is increased in these people. Thigh is the most common site of lesion. Abdominal wall lesion is rare and can cause diagnostic difficulties due to large dimensions and appearance. We report a 50-year-old obese woman with MLL of anterior abdominal wall. She experienced discomfort while walking and sleeping due to giant MLL of anterior abdominal wall that significantly reduced quality of life. Removal of MLL (weight 22160 g) was followed by favorable cosmetic and functional outcome. Analysis of differences between MLL and soft tissue sarcoma in the era of «obesity epidemic» is valuable for correct diagnosis and treatment of this rare complication. This report is the first case of MLL, registered in Russia. In our opinion, this is associated with insufficient awareness of physicians about this complication of obesity. We hope our observation will help clinicians to identify and treat this complication.

Multiple paragangliomas: a case report

Background

Carotid and vagal paragangliomas (CPGLs and VPGLs) are rare neoplasms that arise from the paraganglia located at the bifurcation of carotid arteries and vagal trunk, respectively. Both tumors can occur jointly as multiple paragangliomas accounting for approximately 10 to 20% of all head and neck paragangliomas. However, molecular and genetic mechanisms underlying the pathogenesis of multiple paragangliomas remain elusive.

Case presentation

We report a case of multiple paragangliomas in a patient, manifesting as bilateral CPGL and unilateral VPGL. Tumors were revealed via computed tomography and ultrasound study and were resected in two subsequent surgeries. Both CPGLs and VPGL were subjected to immunostaining for succinate dehydrogenase (SDH) subunits and exome analysis. A likely pathogenic germline variant in the SDHD gene was indicated, while likely pathogenic somatic variants differed among the tumors.

Conclusions

The identified germline variant in the SDHD gene seems to be a driver in the development of multiple paragangliomas. However, different spectra of somatic variants identified in each tumor indicate individual molecular mechanisms underlying their pathogenesis.

Mutation profiling in eight cases of vagal paragangliomas

Background

Vagal paragangliomas (VPGLs) belong to a group of rare head and neck neuroendocrine tumors. VPGLs arise from the vagus nerve and are less common than carotid paragangliomas. Both diagnostics and therapy of the tumors raise significant challenges. Besides, the genetic and molecular mechanisms behind VPGL pathogenesis are poorly understood.

Methods

The collection of VPGLs obtained from 8 patients of Russian population was used in the study. Exome library preparation and high-throughput sequencing of VPGLs were performed using an Illumina technology.

Results

Based on exome analysis, we identified pathogenic/likely pathogenic variants of the SDHx genes, frequently mutated in paragangliomas/pheochromocytomas. SDHB variants were found in three patients, whereas SDHD was mutated in two cases. Moreover, likely pathogenic missense variants were also detected in SDHAF3 and SDHAF4 genes encoding for assembly factors for the succinate dehydrogenase (SDH) complex. In a patient, we found a novel variant of the IDH2 gene that was predicted as pathogenic by a series of algorithms used (such as SIFT, PolyPhen2, FATHMM, MutationTaster, and LRT). Additionally, pathogenic/likely pathogenic variants were determined for several genes, including novel genes and some genes previously reported as associated with different types of tumors.

Conclusions

Results indicate a high heterogeneity among VPGLs, however, it seems that driver events in most cases are associated with mutations in the SDHx genes and SDH assembly factor-coding genes that lead to disruptions in the SDH complex.

[Miocarditis in Patients with COVID-19 Confirmed by Immunohistochemical]

Aim      Despite the regular heart damage in patients with coronavirus pneumonia caused by SARS-Cov-2, a possibility of developing lymphocytic myocarditis as a part of COVID-19 remains unsubstantiated. The aim of this study was to demonstrate a possibility of lymphocytic myocarditis and to study its morphological features in patients with the novel coronavirus infection (COVID-19) with a severe course.Material and methods   Postmortem data were studied for 5 elderly patients (74.8±4.4 years; 3 men and 2 women) with the novel coronavirus infection and bilateral, severe polysegmental pneumonia (stage 3-4 by computed tomography). COVID-19 was diagnosed based on the typical clinical presentation and positive polymerase chain reaction test in nasopharyngeal swabs. All patients were treated in different hospitals repurposed for the treatment of patients with COVID-19. A standard histological study was performed with hematoxylin and eosin, toluidine blue, and van Gieson staining. Serial paraffin slices were studied immunohistochemically with antibodies to CD3, СD68, CD20, perforin, and toll-like receptors (TLR) 4 and 9.Results In none of the cases, myocarditis was suspected clinically, added to the diagnosis or indicated as a possible cause of death. IHD and acute myocardial infarction were mentioned as error diagnoses not confirmed by the postmortem examination. The morphological examination of the heart identified signs of lymphocytic myocarditis consistent with Dallas criteria for this diagnosis. Myocardial infiltrate was characterized in detail, and a combined inflammatory damage of endocardium and pericardium was described. The immunohistochemical study with cell infiltrate typing confirmed the presence of CD3-positive Т lymphocytes and the increased expression of TLR-4. A picture of coronaritis, including that with microvascular thrombosis, was found in all cases.Conclusion      A possibility for development of lymphocytic viral myocarditis in COVID-19 was confirmed morphologically and immunohistochemically. Specific features of myocarditis in COVID-19 include the presence of coronaritis and a possible combination of myocarditis with lymphocytic endo- and pericarditis.

[Predicting of pancreatic fistula after pancreatoduodenectomy]

OBJECTIVE

Identifying the opportunity of objective prognosis of pancreatic fistula emergence after pancreatoduodenectomy.

MATERIAL AND METHODS

In the department of abdominal surgery in 2016-2019, 177 pancreatoduodenectomies for pancreatobiliary tumors were performed. 4 risk factors were identified: type of tumor, preoperative CT with an accumulation coefficient in the pancreas of more than 1, soft pancreas, the number of functioning acinar structures identified during intraoperative histological examination. Statistical data processing and predictive modeling were performed using a binary logistic regression model.

RESULTS

Clinically significant pancreatic fistula was developed in 47 (26,6%) patients. Risk indicators for the occurrence of pancreatic fistula depending on the presence or absence of risk factors were obtained. Groups of patients were identified that require various preventive and therapeutic measures aimed to treat postoperative pancreatitis and its consequences.

CONCLUSION

Predicting the pancreatic fistula emergence allows to take timely preventive and therapeutic measures, both minimal and aggressive (early extracorporeal detoxification, pancreatectomy), which may lead to complications. Well-reasoned pancreatectomy and extracorporeal detoxification is a surgeon's defense in an insured case or legal conflict.

[Duodenopancreatectomy for pancreatic tumors - pros and cons]

AIM

To optimize surgical treatment of multiple and advanced pancreatic tumors.

MATERIAL AND METHODS

There were 852 patients with various pancreatic tumors for the period 2011 - September 2019. Duodenopancreatectomy (DPE) was performed in 18 patients. Locally advanced ductal adenocarcinoma was diagnosed in 10 patients, acinar cell carcinoma - in 1 patient, multiple neuroendocrine tumors - in 4 cases, intraductal papillary mucinous tumor - in 2 patients, multiple metastases of renal cell carcinoma - in 1 patient. This procedure was avoided in 9 patients who underwent alternative operations: pancreatoduodenectomy (PDE) with pancreatic body resection for intraductal papillary mucinous tumor - 5 cases, two-stage (2) and one-stage (1) distal pancreatectomy and PDE for multiple neuroendocrine tumors - 2 patients, simultaneous pancreatic head resection and distal pancreatectomy for multiple metastases of renal cell carcinoma - 1 patient.

RESULTS

Postoperative complications occurred in 14 patients after DPE (77.8%) and in 5 patients after alternative operations (55.5%). Alternative procedures in patients with neuroendocrine tumors, intraductal papillary mucinous tumors and metastases of renal cell carcinoma ensured radical surgical treatment. These patients did not need for insulin replacement therapy and enzyme drugs.

CONCLUSION

Strict adherence to oncological canons and differentiated approach in patients with multiple neuroendocrine tumors, metastases of renal cell carcinoma and intraductal papillary mucinous tumors are essential to avoid DPE in some cases in favor of alternative operations.

[Novel Genes Associated with the Development of Carotid Paragangliomas]

Carotid paragangliomas (CPGLs) are rare neuroendocrine tumors of the head and neck. "Germline" and somatic mutations in a number of genes were shown to be associated with the development of CPGLs; however, molecular mechanisms of the tumor pathogenesis have not been fully understood. In the work, we have used whole exome sequencing data of 52 CPGLs obtained earlier. Using MutSigCV, the search for genes with high mutation rate was performed. Thirty four genes (MADCAM1, SARM1, ZFPM1, CTDSP2, DSPP, POTED, ANP32B, FRG2B, BAGE3, CCDC89, ACOT2, KRTAP10-1, ATXN1, GXYLT1, MUC2, AQP7, TMPRSS13, KRTAP4-3, PRR21, PSPH, PLBD1, ZNF595, IGSF3, PRR16, FAM157A, KCNJ12, HYDIN, IGFBP2, KIAA1671, DISC1, MUC6, XKR3, HRNR, and MUC4) potentially associated with the CPGL initiation and progression were revealed. The involvement of these genes in the pathogenesis of CPGLs was first shown, and possible mechanisms of their participation in that were discussed.

Novel potential causative genes in carotid paragangliomas

Background

Carotid paragangliomas (CPGLs) are rare neuroendocrine tumors that arise from the paraganglion at the bifurcation of the carotid artery and are responsible for approximately 65% of all head and neck paragangliomas. CPGLs can occur sporadically or along with different hereditary tumor syndromes. Approximately 30 genes are known to be associated with CPGLs. However, the genetic basis behind the development of these tumors is not fully elucidated, and the molecular mechanisms underlying CPGL pathogenesis remain unclear.

Methods

Whole exome and transcriptome high-throughput sequencing of CPGLs was performed on an Illumina platform. Exome libraries were prepared using a Nextera Rapid Capture Exome Kit (Illumina) and were sequenced under 75 bp paired-end model. For cDNA library preparation, a TruSeq Stranded Total RNA Library Prep Kit with Ribo-Zero Gold (Illumina) was used; transcriptome sequencing was carried out with 100 bp paired-end read length. Obtained data were analyzed using xseq which estimates the influence of mutations on gene expression profiles allowing to identify potential causative genes.

Results

We identified a total of 16 candidate genes (MYH15, CSP1, MYH3, PTGES3L, CSGALNACT2, NMD3, IFI44, GMCL1, LSP1, PPFIBP2, RBL2, MAGED1, CNIH3, STRA6, SLC6A13, and ATM) whose variants potentially influence their expression (cis-effect). The strongest cis-effect of loss-of-function variants was found in MYH15, CSP1, and MYH3, and several likely pathogenic variants in these genes associated with CPGLs were predicted.

Conclusions

Using the xseq probabilistic model, three novel potential causative genes, namely MYH15, CSP1, and MYH3, were identified in carotid paragangliomas.

Mutational load in carotid body tumor

Background

Carotid body tumor (CBT) is a rare neoplasm arising from paraganglion located near the bifurcation of the carotid artery. There is great intra-tumor heterogeneity, and CBT development could be associated with both germline and somatic allelic variants. Studies on the molecular genetics of CBT are limited, and the molecular mechanisms of its pathogenesis are not fully understood. This work is focused on the estimation of mutational load (ML) in CBT.

Methods

Using the NextSeq 500 platform, we performed exome sequencing of tumors with matched lymph node tissues and peripheral blood obtained from six patients with CBT. To obtain reliable results in tumors with low ML, we developed and successfully applied a complex approach for the analysis of sequencing data. ML was evaluated as the number of somatic variants per megabase (Mb) of the target regions covered by the Illumina TruSeq Exome Library Prep Kit.

Results

The ML in CBT varied in the range of 0.09–0.28/Mb. Additionally, we identified several pathogenic/likely pathogenic somatic and germline allelic variants across six patients studied (including TP53 variants).

Conclusions

Using the developed approach, we estimated the ML in CBT, which is much lower than in common malignant tumors. Identified variants in known paraganglioma/pheochromocytoma-causative genes and novel genes could be associated with the pathogenesis of CBT. The obtained results expand our knowledge of the mutation process in CBT as well as the biology of tumor development.

Molecular markers of paragangliomas/pheochromocytomas

Paragangliomas/pheochromocytomas comprise rare tumors that arise from the extra-adrenal paraganglia, with an incidence of about 2 to 8 per million people each year. Approximately 40% of cases are due to genetic mutations in at least one out of more than 30 causative genes. About 2530% of pheochromocytomas/paragangliomas develop under the conditions of a hereditary tumor syndrome a third of which are caused by mutations in the VHL gene. Together, the gene mutations in this disorder have implicated multiple processes including signaling pathways, translation initiation, hypoxia regulation, protein synthesis, differentiation, survival, proliferation, and cell growth. The present review contemplates the mutations associated with the development of pheochromocytomas/paragangliomas and their potential to serve as specific markers of these tumors and their progression. These data will improve our understanding of the pathogenesis of these tumors and likely reveal certain features that may be useful for early diagnostics, malignancy prognostics, and the determination of new targets for disease therapeutics.

Exome analysis of carotid body tumor

Background

Carotid body tumor (CBT) is a form of head and neck paragangliomas (HNPGLs) arising at the bifurcation of carotid arteries. Paragangliomas are commonly associated with germline and somatic mutations involving at least one of more than thirty causative genes. However, the specific functionality of a number of these genes involved in the formation of paragangliomas has not yet been fully investigated.

Methods

Exome library preparation was carried out using Nextera® Rapid Capture Exome Kit (Illumina, USA). Sequencing was performed on NextSeq 500 System (Illumina).

Results

Exome analysis of 52 CBTs revealed potential driver mutations (PDMs) in 21 genes: ARNT, BAP1, BRAF, BRCA1, BRCA2, CDKN2A, CSDE1, FGFR3, IDH1, KIF1B, KMT2D, MEN1, RET, SDHA, SDHB, SDHC, SDHD, SETD2, TP53BP1, TP53BP2, and TP53I13. In many samples, more than one PDM was identified. There are also 41% of samples in which we did not identify any PDM; in these cases, the formation of CBT was probably caused by the cumulative effect of several not highly pathogenic mutations. Estimation of average mutation load demonstrated 6–8 mutations per megabase (Mb). Genes with the highest mutation rate were identified.

Conclusions

Exome analysis of 52 CBTs for the first time revealed the average mutation load for these tumors and also identified potential driver mutations as well as their frequencies and co-occurrence with the other PDMs.

Electronic supplementary material

The online version of this article (10.1186/s12920-018-0327-0) contains supplementary material, which is available to authorized users.

[The expression of moesin, p21-activated kinase 4 (PAK 4), matrix metalloproteinases (MMP 2, MMP 9), and CD34 in the eutopic and ectopic endometrium in adenomyosis]

OBJECTIVE

To investigate the expression of moesin, p21-activated kinase 4 (PAK 4), matrix metalloproteinases (MMP 2, MMP 9), and CD34 in the eutopic and ectopic endometrium in different forms of adenomyosis.

MATERIAL AND METHODS

Fifty uteri removed for diffuse adenomyosis and for adenomyomas were examined in reproductive-aged (n=25) and premenopausal (n=25) women. A comparison group included 20 uteri removed for intramural and subserosal fibroids in reproductive-aged and premenopausal women. The investigators performed histological and immunohistochemical (using antibodies to moesin, PAK 4, MMP 2, MMP 9, and CD34) examinations of the eutopic and ectopic endometrium.

RESULTS

Different forms of adenomyosis were characterized by the irregular border of the endometrium and myometrium due to that there were multiple foci of ingrowth of the basal layer of the endometrium through the terminal plate into the myometrium. In both diffuse adenomyosis and adenomyomas, the basal layer of the eutopic and ectopic endometrium differed many (3-8.5) times, showing the higher expression of the enzymes in the epithelial and stromal cells, which affected their invasive activity (moesin, PAK 4, MMP 2 and MMP 9), and the increased number of CD34 cells in its stroma. At the same time, there were no statistically significant differences in their expression in the basal layer of the eutopic and ectopic endometrium in diffuse adenomyosis and adenomyomas.

CONCLUSION

The findings favor the theory of the pathogenesis of adenomyosis due to the invasion of the eutopic endometrium into the myometrium.

[Clinico-pathological factors and prognosis scale for portal cholangiocarcinoma]

INTRODUCTION

The objective of this study was to derive a prognostic scale to predict overall survival (OS) after a curative resection of perihilar cholangiocarcinoma (PHC).

MATERIAL AND METHODS

The data of 55 patients with portal cholangiocarcinoma were analysed. Patients were treated at the A.V. Vishnevsky Institute of Surgery from 2011 to 2015. Surgical treatment after biliary decompression was performed in 37 (67.3%) patients. In the long-term period we observed 36 (97.3%) of the operated patients. The dependence of the OS of clinical and pathological factors of the tumor was analysed using mono- and multifactor regression analysis of Cox proportional hazards models for all operated patients.

RESULTS

Total 1-3-, 5-year survival rate was 75.1, 60.5, 37.7, 35% respectively. Significant prognostic factors (monofactorial analysis) include perineural (p=0,05) and vascular invasion (p=0,049), R1 resection (p=0,01), disease stage III or higher (p=0,03), invasion of SI liver (p=0,004), tumor cells differentiation degree (grade) 2 and higher (p=0,0006). Multifactor analysis revealed that the low OS have determined by perineural (p=0,05) and vascular invasion (p=0,008), the degree of differentiation of tumor cells (p=0,001), disease stage (p=0,05), surgical resection margin (p=0.0345). Developed method of predicting OS is a score of prognostic factors.

CONCLUSION

The scale of individual prognosis in patients PHC takes into account both clinical and histopathological tumor characteristics. This scale may be useful to optimize the individual treatment.

[Mucinous cystic liver tumors: diagnosis and surgical treatment]

AIM

To optimize diagnostics and treatment of cystic liver tumors.

MATERIAL AND METHODS

The analysis included outcomes of 46 patients with liver cystic tumors.

RESULTS AND DISCUSSION

The use of abdominal Doppler-sonography (37 patients), abdominal contrast-enhanced CT (44 patients) and MRI of abdominal cavity with MR-cholangiography (24 patients) defined radiological semiotics of cystic liver diseases. The most important features of cystic tumors are intraluminal septums with blood flow (82% of patients), solid component (6.8%), daughterly cysts (11.3%), as well as biliary hypertension (39.2% of patients). Research of oncomarkers (CEA, SA 19-9, AFP) in 40 patients showed increased level of SA 19-9 only in case of cystadenocarcinoma and intraductal papillary mucinous neoplasm of biliary type. Benign and malignant cystic tumors had increased contents of oncomarkers in all cases. Surgical treatment was used in 42 patients. Extended liver resections were performed in 10 (23.8%) patients, atypical and anatomical resections (removal of less than 3 segments) - in 31 (73.8%) patients. In one case we applied cryoablation of CA in segment I of the liver in view of invasion into the wall of inferior vena cava and hepatoduodenal ligament. In 2 cases surgery was carried out laparoscopically. Also robot-assisted technique was used in 3 patients. Immunohistochemical study was performed in 22 (44.8%) patients. The diagnosis of CAC and biliary type of IPMN was confirmed in case of high expression of CK7, SK19, MUC1, S100p, SDH2, p53 antibodies. Cystadenomas were associated with moderate expression of ER, PR and p53 antibodies by stroma and CK7, SK19, CDX2, MUC1, S100p antibodies by epithelium.

CONCLUSION

There are considerable difficulties of differential diagnosis of liver cystic tumors. Therefore, the use of single algorithm of diagnostics and treatment is necessary to confirm accurately the diagnosis at the perioperative stage. Cystic tumor is more likely to be assumed in women with solitary cyst in segment IV of liver. If the diagnosis is suspected or confirmed anatomical liver resection with complete tumor removal is necessary to prevent the recurrence.

[Surgical treatment of retroperitoneal masses]

AIM

To improve the results of treatment of patients with retroperitoneal tumors.

MATERIAL AND METHODS

The study included 83 patients with retroperitoneal tumors including 57 cases of benign tumors and 26 patients with malignancies. Laparotomy (Lt), robot-assisted (RA) and laparoscopic (Ls) techniques were used in 35, 34 and 14 patients respectively. Median tumor sizes in the largest dimension were 102 mm, 75 mm and 81.5 mm in Lt, RA and Ls groups respectively.

RESULTS

Average time of surgery was 112.5 minutes in Lt-group, 140 min in RA group and 125 minutes in Ls group. Median blood loss was 125 ml, 50 ml and 50 ml in the same groups respectively. Conversion was performed in 1 patient during RA-surgery and in 7 patients during laparoscopy. Postoperative complications occurred in 6 patients after laparotomy and in 5 patients after RA-intervention. There were no deaths.

CONCLUSION

Comprehensive evaluation of different surgical methods is necessary to achieve successful treatment of retroperitoneal tumors. Conventional approach is indicated for tumors over 10 cm while minimally invasive techniques are justified for tumors less than 10 cm. RA-interventions facilitates surgery for tumors located in difficult areas and small anatomical spaces as well as for neoplasms adjacent to great vessels.

[Haemangioma of the left atrium]

Presented herein is a clinical case report concerning successful surgical management of a rare variety of a primary tumour of the heart, i. e., a capillary haemangioma of the left atrium, simulating by the contours and localization a myxoma. The final diagnosis was verified only by histological examination. The authors describe difficulties of diagnosis of the disease involved, underlying the necessity of plastic correction for restoration of the normal anatomical configuration of the heart. This is followed by a review of the literature, reflecting a possible course of the disease, problems of diagnosis, and therapeutic policy.

Effect of lentivirus-mediated shRNA inactivation of HK1, HK2, and HK3 genes in colorectal cancer and melanoma cells

Background

The switch from oxidative phosphorylation to glycolysis in proliferating cancer cells, even under aerobic conditions, has been shown first in 1926 by Otto Warburg. Today this phenomenon is known as the “Warburg effect” and recognized as a hallmark of cancer. The metabolic shift to glycolysis is associated with the alterations in signaling pathways involved in energy metabolism, including glucose uptake and fermentation, and regulation of mitochondrial functions. Hexokinases (HKs), which catalyze the first step of glycolysis, have been identified to play a role in tumorigenesis of human colorectal cancer (CRC) and melanoma. However, the mechanism of action of HKs in the promotion of tumor growth remains unclear.

Results

The purpose of the present study was to investigate the effect of silencing of hexokinase genes (HK1, HK2, and HK3) in colorectal cancer (HT-29, SW 480, HCT-15, RKO, and HCT 116) and melanoma (MDA-MB-435S and SK-MEL-28) cell lines using short hairpin RNA (shRNA) lentiviral vectors. shRNA lentiviral plasmid vectors pLSLP-HK1, pLSLP-HK2, and pLSLP-HK3 were constructed and then transfected separately or co-transfected into the cells. HK2 inactivation was associated with increased expression of HK1 in colorectal cancer cell lines pointing to the compensation effect. Simultaneous attenuation of HK1 and HK2 levels led to decreased cell viability. Co-transfection with shRNA vectors against HK1, HK2, and HK3 mRNAs resulted in a rapid cell death via apoptosis.

Conclusions

We have demonstrated that simultaneous inactivation of HK1 and HK2 was sufficient to decrease proliferation and viability of melanoma and colorectal cancer cells. Our results suggest that HK1 and HK2 could be the key therapeutic targets for reducing aerobic glycolysis in examined cancers.

[Diagnosis and treatment of duodenal dystrophy in patients with chronic pancreatitis]

AIM

to define optimal treatment of duodenal dystrophy in patients with chronic pancreatitis.

MATERIAL AND METHODS

515 patients with chronic pancreatitis have been treated for the period 2004-2015 in A.V.Vishnevsky Institute of Surgery. Duodenal dystrophy (DD) was diagnosed in 79 (15.3%) of them. The diagnosis was confirmed by sonography, CT, MRI and endosonography. 5 patients are under observation without surgery. 74 patients were operated after previous medical therapy during 39 months on the average. Pancreatoduodenectomy was performed in 36 patients. Organ-sparing interventions were applied in 34 cases including different duodenal resections in 20 patients and pancreatic head resections in different modifications in 14 cases. 4 patients underwent palliative surgery. Chronic pancreatitis and DD were verified by morphological analysis of specimens. Long-term results were estimated in 47 patients. Median follow-up was 49.9 months.

RESULTS

X-ray diagnostics showed that DD was combined with chronic pancreatitis in 87.3% of cases while morphological analysis revealed 93.8%. Clinical signs of DD were caused by striated pancreatitis in 69.6% and ectopic pancreatic tissue in 30.4%. Clinical manifestations of DD did not depend on its cause and were presented by symptoms of chronic pancreatitis. Postoperative complications occurred in 25 (34.7%) patients. There were 33.5% of complications after pancreatoduodenectomy and 70% after duodenal resection. 1 patient died. Overall mortality was 1,3%. In long-term period complete regression of symptoms was observed in 66% of cases, significant improvement - in 32%, absence of the effect - in 2%.

CONCLUSION

Medical therapy should be preferred for patients with DD and chronic pancreatitis. Surgery is indicated in case of persistent pain, complicated course of chronic pancreatitis and duodenal obstruction. Pancreatoduodenectomy and pancreatic head resection are preferred.

Organic hyperinsulinism: radiological diagnostics and surgical treatment

AIM

To optimize the diagnosis and surgical treatment of insulinoma and nesidioblastosis.

MATERIAL AND METHODS

42 patients with organic hyperinsulinism (OH) were operated. There were 39 cases of insulinoma including 2 patients with insulinoma combined with nesidioblastosis and 3 cases of nesidioblastosis alone. Preoperative ray imaging consisted of percutaneous, endoscopic and intraoperative sonography, contrast-enhanced computed tomography, magnetic resonance imaging (MRI). Functional test included arterial-stimulated blood sampling (ASBS). Laparotomy and robot-assisted techniques were used in 22 and 20 patients.

RESULTS

Sensitivity was 62.0%, 76.9%, 83.3%, 87.5%, 94.8% and 100% in percutaneous sonography, CT, endoscopic sonography, MRI, intraoperative sonography and ASBS respectively. Postoperative complications were observed in 14 and 6 patients after conventional and robot-assisted surgery. 2 patients died. Overall mortality was 4.8%. None patient had recurrent hypoglycemic conditions in long-term postoperative period (mean follow-up 18.7 months).

CONCLUSIONS

Comprehensive survey allowed to define the cause of OH. Minimally invasive organ-sparing surgery has satisfactory immediate and remote results in these patients.

[Robot-assisted operations for non-organ retroperitoneal tumors]

MATERIAL AND METHODS

Robot-assisted operations for non-organ retroperitoneal tumors were performed in 20 patients. The biggest tumor's diameter was 160 mm, the smallest--32 mm, mean value was 79.1±37.8 mm. According to morphological investigation data lymphangioma was diagnosed in 4 (20%) patients, lipoma--in 3 (15%) cases, peritoneal cyst--in 2 (10%) patients. Solitary lymphatic node, teratoma, leiomyosarcoma, accessory stomach, bronchogenic cyst, adenogenous cancer, ureterocele, megaureter, schwannoma, leiomyoma, malignant paraganglioma were observed in 1 (5%) case respectively.

RESULTS

Surgery duration was 138±55.9 min. Blood loss was 69±112.7 ml (range 0-500 ml). Intraoperative complications (bleeding) were diagnosed in 3 (15%) patients. There were no conversions. Robot-assisted variant has been demonstrated in case of non-organ retroperitoneal tumors with diameter not more than 100-120 mm.

Value of two-phase dynamic multidetector computed tomography in differential diagnosis of post-inflammatory strictures from esophageal cancer

AIM: To characterize the computed tomography (CT) findings in patients with post-inflammatory esophageal strictures (corrosive and peptic) and reveal the optimal scanning phase protocols for distinguishing post-inflammatory esophageal stricture and esophageal cancer.

METHODS: Sixty-five patients with esophageal strictures of different etiology were included in this study: 24 patients with 27 histopathologically confirmed corrosive strictures, 10 patients with 12 peptic strictures and 31 patients with esophageal cancer were evaluated with a two-phase dynamic contrast-enhanced MDCT. Arterial and venous phases at 10 and 35 s after the attenuation of 200 HU were obtained at the descending aorta, with a delayed phase at 6-8 min after the start of injection of contrast media. For qualitative analysis, CT scans of benign strictures were reviewed for the presence/absence of the following features: “target sign”, luminal mass, homogeneity of contrast medium uptake, concentric wall thickening, conically shaped suprastenotic dilatation, smooth boundaries of stenosis and smooth mucous membrane at the transition to stenosis, which were compared with a control group of 31 patients who had esophageal cancer. The quantitative analysis included densitometric parameter acquisition using regions-of-interest measurement of the zone of stenosis and normal esophageal wall and the difference between those measurements (ΔCT) at all phases of bolus contrast enhancement. Esophageal wall thickening, length of esophageal wall thickening and size of the regional lymph nodes were also evaluated.

RESULTS: The presence of a concentric esophageal wall, conically shaped suprastenotic dilatation, smooth upper and lower boundaries, “target sign” and smooth mucous membrane at the transition to stenosis were suggestive of a benign cause, with sensitivities of 92.31%, 87.17%, 94.87%, 76.92% and 82.05%, respectively, and specificities of 70.96%, 89.66%, 80.65%, 96.77% and 93.55%, respectively. The features that were most suggestive of a malignant cause were eccentric esophageal wall thickening, tuberous upper and lower boundaries of stenosis, absence of mucous membrane visualization, rupture of the mucous membrane at the upper boundary of stenosis, cup-shaped suprastenotic dilatation, luminal mass and enlarged regional lymph nodes with specificities of 92.31% 94.87%, 67.86%, 100%, 97.44%, 94.87% and 82.86%, respectively and sensitivities of 70.97%, 80.65%, 96.77%, 80.65%, 54.84%, 87.10% and 60%, respectively. The highest tumor attenuation occurred in the arterial phase (mean attenuation 74.13 ± 17.42 HU), and the mean attenuation difference between the tumor and the normal esophageal wall (mean ΔCT) in the arterial phase was 23.86 ± 19.31 HU. Here, 11.5 HU of ΔCT in the arterial phase was the cut-off value used to differentiate esophageal cancer from post-inflammatory stricture (P = 0.000). The highest attenuation of post-inflammatory strictures occurred in the delayed phase (mean attenuation 71.66 ± 14.28 HU), and the mean ΔCT in delayed phase was 34.03 ± 15.94 HU. Here, 18.5 HU of ΔCT in delayed phase was the cut-off value used to differentiate post-inflammatory stricture from esophageal cancer (P < 0.0001).

CONCLUSION: The described imaging findings reveal high diagnostic significance in the differentiation of benign strictures from esophageal cancer.

[Minimally invasive surgical treatment of gastrointestinal stromal tumor]

It was operated 24 patients with gastrointestinal stromal tumor (GIST). Robot-assisted method was applied in 15 observations, laparoscopy - in 9 patients. Laparoscopic operations were preferable for GIST localized in anterior wall or greater curvature of stomach, in small intestine and caecum. Robot-assisted GIST removal was performed in case its location in posterior wall of stomach, on lesser curvature of stomach, in duodenum, what required organ's dissection or had a risk of great vessel injury.

[Robot-assisted resection of duodenal inferior horizontal part and duodeno-jejunal transition]

Robot-assisted resection of duodenal inferior horizontal part and duodeno-jejunal transition was performed in 5 patients with tumors in this area including gastrointestinal stromal tumor in 4 cases and jejunal adenocarcinoma in 1 case. It is suggested there section method with vertical and inferior horizontal parts and pancreatic head dissection right-to-left. There were no intra- and postoperative complications. Robot-assisted resection of duodenal inferior horizontal part and duodeno-jejunal transition may be successfully used for tumors with diameter less than 5-6 cm.

[Epinephros metastasis of colorectal cancer complicated by tumor thrombosis of inferior vena cava]

Metastasis of colorectal cancer (CRC) in an adrenal gland develops in 1.8% of cases (in synchrony or in metachrony) for patients with liver metastatic lesion and aggravates for certain prognosis for long-term survival. There are no data concerning colorectal metastasis in an adrenal gland with tumor thrombosis of inferior vena cava (IVC) in world-wide literature. A patient, 57 years old, on 04.29.11 underwent palliative distal sigmoid colectomy in respect of CRC pT3N2M1 (metastatic lesion of liver right lobe). Process stabilization was noticed after 4 courses of polychemotherapy. On 07.28.11 she underwent right-sided hemihepatectomy. She underwent further 4 courses in accordance with the same scheme. On 12.06.13 case-control USI and multi-layer spiral CT of abdominal cavity detected mass lesion in the right adrenal gland, it was estimated as metastatic lesion with compression of inferior vena cava and thrombosis in its lumen at retroliver segment level. Right-sided adrenalectomy. Thrombectomy of IVC was carried out in the condition of total vascular isolation. Taking into account metastasis respectability in an adrenal gland and small extent of a tumor thrombus we suppose the described surgical practice to be justified. The problem of neoadjuvant chemotherapy prescription is still controversial.

[Nesidioblastosis (diagnosis, surgical treatment)]

INTRODUCTION

Nesidioblastosis (NB) is rare disease with organic hyperinsulinism syndrome and caused by diffuse hyperplasia and/or hypertrophy of pancreatic islands of Langerhans.

MATERIAL AND METHODS

The results of surgical treatment of 3 patients with NB are presented. In all patients the diagnosis was suspected at the preoperative stage and confirmed by histological examination later. Herewith in 2 patients NB was combined with insulinoma. All patients underwent corpora-caudal pancreatectomy.

RESULTS

In postoperative period one patient hadn't episodes of hypoglycemia for the entire follow-up period (5 months), in another patient hypoglycemic states occurred at 1.5 months after surgery. The third patient required pancreatic head extirpation at 11 days after surgery due to persistent severe course of organic hyperinsulinism. In immediate postoperative period in the same patient hyperinsular hypoglycemia was observed that pointed on extrapancreatic source of insulin secretion. However contrast-enhanced CT did not reveal any formations.

CONCLUSION

Thus, corpora-caudal pancreatectomy is preferable as surgical treatment. Results of surgical management can provide a complete regression of the symptoms, but do not guarantee absence of recurrence and even any changes in frequency and severity of hypoglycemic states.

[Microscopic investigation of vessel wall after endovascular catheter atherectomy]

Endovascular target catheter atherectomy (ETCA) - method of artery patency allowing to obtain occlusion substrate. Given the high destructive effect of atherectome's elements on tissue the objective was determination possibility of histological and electron microscopic investigation of this substrate after atherectomy. The research included 8 patients who underwent ETCA of legs arteries. It was observed substrate removal from broken stent in 1 case. 2 of 8 patients had diabetes. Obtained substrate was available for histological and electron microscopic investigation. Atherosclerosis was confirmed in all cases. It was not observed substrate significant morphological changes in patients with presence or absence of diabetes. Microscopic investigation of substrate from broken stent shows pronounced development of granulation tissue that was regarded as special form of reparative regeneration. Finding internal elastic membrane during microscopic investigation in some cases proves radical intervention. The authors consider that microscopic investigation of substrate after ETCA may be used for diagnosis verification, thorough analysis of morphological changes in lesion area and radicalism of atherectomy.

[The rare case of laryngeal lesion in idiopathic Kaposi's sarcoma]

The case report of laryngeal Kaposi's sarcoma (KS) in 59 year old HIV-negative man infected by herpes virus 8 (HHV-8) is in the paper. The primary onset of KS was on the legs. Lesion of laryngeal mucosa was developed sequentially, resulted in laryngeal stenosis and led to application of tracheostome. The skin and laryngeal mucosa lesions had homotypic histological structure and corresponded to early manifestation of KS preceded tumor node appearance.

[The histoarchitectonics of the pharyngeal tonsil in age aspect: morphometric and immunohistochemical study]

To assess immune responsiveness in children requires basic knowledge of the morphofunctional organization of the immune system that involves lymphoepithelial organs of Waldeyer's ring. Among them, the pharyngeal tonsil is the first to respond to both respiratory tract infection and local vaccination, which determines the need for investigations of its immune responsiveness when a child's immune system is developed. The morphometry of the histological structures of the pharyngeal tonsil and the cell immunophenotyping of this organ in age aspect are used to solve this task. The basic findings are needed to assess and compare different therapeutic approaches (vaccination and immunotherapy).