[Dedicated to the memory of Yuri Nikolaevich Volkov]. / Pamyati Yuriya Nikolaevicha Volkova posvyashchaetsya.

One of the brilliant representatives of medicine of the XX century is Yuri Nikolaevich Volkov. His results of scientific and practical activities are impressive in their scale. They are represented in numerous printed works devoted to the most important theoretical and practical aspects of otorhinolaryngology. Yuri Nikolaevich Volkov also created some inventions. His works are included in a four-volume guide to otorhinolaryngology and textbooks for medical students.

[Active surgical approach for retroperitoneal liposarcoma]. / Rol' aktivnoi khirurgicheskoi taktiki pri zabryushinnoi liposarkome.

OBJECTIVE: To assess the influence of active surgical approach on the long-term postoperative outcomes in patients with retroperitoneal liposarcoma. MATERIAL AND METHODS: A retrospective study included 190 patients with retroperitoneal liposarcoma. The effect of malignancy grade, adjuvant chemotherapy, number of separate tumor nodes in primary neoplasm and the first relapse, as well as the number of previous total resections on survival rate was analyzed. RESULTS: Overall and relapse-free survival is significantly worse in patients with high-grade retroperitoneal liposarcoma (G2-3) compared to low-grade (G1) tumor (plog-rank=0.000). Multifocal growth of primary tumor (p=0.869; plog-rank=0.607) and multiple (>1) separately located nodes in abdominal cavity and retroperitoneal space at the first relapse (plog-rank=0.158 to 0.985) did not significantly impair prognosis after total resection of all types of retroperitoneal liposarcoma regardless malignancy grade. Adjuvant chemotherapy does not significantly improve relapse-free survival. Overall survival was significantly higher in patients who underwent ≥4 previous total resections compared to 1 surgical treatment for all types of retroperitoneal liposarcoma regardless malignancy grade (p=0.000; plog-rank=0.001). CONCLUSION: The only potentially radical treatment for patients with retroperitoneal liposarcoma is surgery. We reported the advantages of active surgical approach for improvement of long-term outcomes in patients with retroperitoneal liposarcoma.

[Surgical and combined treatment of patients with duodenal stromal tumors]. / Osobennosti khirurgicheskogo i kombinirovannogo lecheniya bol'nykh stromal'noi opukhol'yu dvenadtsatiperstnoi kishki.

OBJECTIVE: To evaluate the immediate and long-term results of surgical and combined treatment of patients with duodenal stromal tumors. MATERIAL AND METHODS: There were 47 patients with duodenal stromal tumors for the period 2002-2019. All patients underwent treatment at the Blokhin National Cancer Research Center. Six patients had metastatic disease, 2 ones - a rare syndrome of duodenal stromal tumor associated with neurofibromatosis type 1, other 39 patients had a localized and locally-advanced disease. Surgical treatment was performed in 37 patients (limited resections (LR) in 24 cases and gastropancreaticoduodenectomy in 13 cases).Incidence of postoperative complications was significantly lower after limited resections compared to gastropancreaticoduodenectomy (22.2% (6/24) vs. 61.5% (8/13), respectively). Severe complications (Clavien-Dindo grade 3) occurred in 4.2% (1/24) vs. 15.3% (2/13) of patients, respectively. Postoperative mortality was absent in both groups. We observed no significant differences in long-term results. Overall 5-year survival was 91% and 70% (p=0.5960), 5-year recurrence-free survival - 65 and 70% (p=0.6226), respectively. CONCLUSION: Considering similar survival rates, lower postoperative morbidity and better quality of life, limited duodenal resections are preferred for duodenal stromal tumors.

[Differentiated surgical approach for retroperitoneal non-organ liposarcoma]. / Differentsirovannyi podkhod v khirurgii zabryushinnykh neorgannykh liposarkom.

OBJECTIVE: To determine the indications for combined and organ-sparing surgery depending on malignancy grade of retroperitoneal liposarcoma. MATERIAL AND METHODS: A retrospective study included 190 patients with retroperitoneal liposarcoma. Influence of malignancy grade, lesion of adjacent organs and resection/excision of adjacent organs on the overall and recurrence-free survival was studied. Moreover, we analyzed the issue of kidney-sparing surgery and nephrectomy. RESULTS: Overall and recurrence-free survival were significantly worse in high grade (G2-3) compared to low-grade tumors (G1) (p=0.0001; log-rank test). Visceral invasion was revealed in 23% of patients with low-grade (G1) tumors and 53% of patients with high-grade (G2-3) neoplasms. Visceral invasion significantly impairs overall and recurrence-free survival in both low grade (G1) and high-grade (G2-3) tumors (p=0.0001; log-rank test). In case of low grade (G1) retroperitoneal liposarcoma, overall and recurrence-free survival was similar after combined surgery without histologically confirmed visceral invasion of liposarcoma and organ-sparing surgery (p=0.006; p=0.053; log-rank test). On the contrary, high grade (G2-3) tumor was followed by significantly better overall and recurrence-free survival after combined surgery without histologically confirmed visceral invasion compared to organ-sparing surgery (p=0.006; p=0.053; log-rank test). Recurrence-free survival was similar after kidney-sparing surgery and nephrectomy among patients with low-grade (G1) tumor (p=0.456; log-rank test). In case of high-grade retroperitoneal liposarcoma (G2-3), recurrence-free survival was significantly worse after kidney-sparing surgery compared to nephrectomy (p=0.039; log-rank test). CONCLUSION: Surgery is the only potentially radical treatment of patients with retroperitoneal liposarcoma. Organ-sparing including kidney-sparing surgery is advisable for low-grade liposarcoma (G1). On the contrary, organ-sparing surgery impairs long-term results and prognosis in patients with high-grade tumors (G2-3). Combined operations including nephrectomy are justified for high-grade retroperitoneal liposarcoma (G2-3).

[Retroperitoneal dedifferentiated liposarcomas: semi-quantitative assessment of the dedifferentiated component and prognosis]. / Zabryushinnye dedifferentsirovannye liposarkomy: polukolichestvennaya otsenka dedifferentsirovannogo komponenta i prognoz.

OBJECTIVE: To evaluate the impact of malignancy grade and the proportion of the dedifferentiated component (DC) in retroperitoneal dedifferentiated liposarcomas (DDLS) on the course and prognosis of the disease. MATERIAL AND METHODS: The retrospective study enrolled 74 patients with primary retroperitoneal DDLS who underwent radical surgical treatment in the N.N. Blokhin National Medical Research Center of Oncology, Ministry of Health of Russia. Histological surgery specimens from all cases of DDLS were reexamined and reclassified. According to malignancy grades and the proportion of the dedifferentiated component in the tumor, the patients were divided into the comparison groups included in the intergroup analysis of overall and relapse-free survival (OS and RFS) rates. The authors also analyzed the relationship between the proportion of the dedifferentiated component in DDLS and the frequency of adjacent organ invasion. RESULTS: Patients with a more than 15% dedifferentiated component had significantly lower OS rates than those with a less than 15% one (p=0.0001; log-rank test). The median OS in the DDLS group with a less than 15% dedifferentiated component was 91 months (95% CI, 82-100); that in the DDLS group with a more than 15% dedifferentiated component was 29 months (95% CI 17-41). The 5-year overall survival rates in the groups with less than 15% and more than 15% dedifferentiated components were 69% and 2%, respectively. The group with a more than 15% dedifferentiated component had significantly lower RFS rates than that with a less than 15% one (p=0.0001; log-rank test). In the DDLS groups with less than 15% and more than 15% dedifferentiated components, the median RFS rates were 25 months (95% CI 23-27) and 13 months (95% CI 8-18), respectively. In these groups, the 2-year RFS rates were equal to 50% and 9%, respectively. In the DDLS groups with less than 15% and more than 15% dedifferentiated components, pathologically confirmed invasion into the adjacent organs was observed in 32% and 63% of cases, respectively. There were no statistically significant differences in the OS and RFS of patients with DDLS according to tumor grade (p=0.069; p=0.102). CONCLUSION: This investigation suggests that DDLS have a more aggressive course with an increasing proportion of the dedifferentiated component in the tumor. Considering the histological variability in the dedifferentiated component, which is demonstrated in the research and scientific literature, as well as lack of a prognostic impact of histological grade, the authors believe that semi-quantitative assessment of the proportion of the dedifferentiated component in DDLS is able to serve as a simple and efficient morphological marker for the course of the disease and prognosis in retroperitoneal DDLS.

[Pharmacokinetic and pharmacodynamic synergism between neuropeptides and lithium in the neurotrophic and neuroprotective action of cerebrolysin].

OBJECTIVE: To study the synergism between neuropeptides and lithium ions. MATERIAL AND METHODS: An experimental model of stroke (chronic bilateral occlusion of the common carotid arteries in rats), neuronal culture studies, histomorphological analyses, determination of micronutrient profile of brain substrates were used. RESULTS: A complex of experimental studies revealed that the effect of cerebrolysin is influenced by the synergism between lithium ions and the neuropeptide contentof this drug. Pharmacokinetic synergism promotes the accumulation of lithium in brain tissues during cerebrolysin treatment. The existence of the pharmacokinetic synergism is evident from the potentiation of neuroprotective effects of the drug under the action of lithium ions established in the model of stroke. CONCLUSION: Lithium ions potentiate neuroprotective effects of cerebrolysin.

Coherent Fluctuation Nephelometry: A Rapid Method for Urine Screening for Bacterial Contamination.

Express-test by the method of coherent fluctuation nephelometry for urine contamination was carried out on two prototype instruments with standard polystyrene photometric cuvettes. We analyzed 209 and 119 urine samples. Due to high sensitivity of the method, up to 50% negative samples were detected within 10 min by initial opacity and 90% negative samples were detected during 3.5 h by registration of the bacterial growth curves.