Introduction. Surgical intervention remains the main method for treatment of the oral mucosa cancer. The generally accepted standard of the resection boundary that provides optimal local control is 5 mm. Adequate boundaries of indentation and choice of the reconstruction method are important issues facing specialists in head and neck tumors.

   Aim. To evaluate parameters of the resection edge in the surgical treatment of malignant neoplasms of the oral mucosa depending on the method of eliminating of the post-resection defect and its effect on the frequency of local relapse.

   Materials and methods. A retrospective analysis included 168 primary patients (50 % men and 50 % women) who received surgical treatment in the head and neck tumor department of the Republican Clinical Oncology Dispensary of the ministry of Health of the Republic of Bashkortostan (ufa) from 2019 to 2023. The median age of patients was 63 years (interquartile range (IQR) 55–69 years). most often, the primary tumor was located in the tongue – in 59.5 % (100/168) of cases. According to the method of post-resection defect removal, the patients were divided into 3 groups. In group 1, reconstruction was performed with local tissues (n = 71), in group 2 – with pedicle flaps (n = 41), and in group 3 – with revascularized flaps (n = 56). The median follow-up period was 18 months (IQR 8–28 months).

   Results. Resection boundaries in group 1 were 7.0 mm (IQR 5.0–12.5 mm), in group 2 – 6.5 mm (IQR 5–13 mm), and in group 3 – 12.5 mm (IQR 7.5–15.0 mm). The overall frequency of near/positive resection boundaries was 14.8 % (25/168). In group 1, it was 15.5 % (11/71), in group 2 – 19.5 % (8/41), in group 3 – 10.7 % (6/56). According to the analysis, relapse of the disease after radical treatment was noted in 32 % (55/168) of patients, of which 14.8 % (25/168) had a local relapse, 12.5 % (21/168) had a regional relapse, and 5.4 % (9/168) developed distant metastases. The frequency of local relapse in group 1 was 18.3 % (13/71), in group 2 – 23.8 % (10/41), in group 3 – 5.5 % (3/56). According to the analysis data, statistically significant differences in the boundary of indentation in the groups were revealed depending on the reconstruction method (p = 0.005).

   Conclusion. Based on the results of the present retrospective analysis, the choice of reconstruction method affects the resection boundary in real clinical practice. Limitations in the surgical indentation that surgeon faces when choosing a method for eliminating a post-resection defect are demonstrated.

   Introduction. The effectiveness of surgical treatment of parotid gland tumors is determined by the frequency of local relapse and functional and aesthetic results, which are determined not only by the anatomical and functional safety of the facial nerve. It is also very important to level aesthetic deformities of the parotid region and reduce the severity of frey’s syndrome.

   Aim. To retrospectively analyze the use of dermal fat grafts to correct defects during operations on the parotid glands.

   Materials and methods. Our study included 7 patients (2 men and 5 women) who were treated at the Leningrad Regional Clinical Oncology Dispensary named after L. D. Roman from 2021 to 2022. The average age of the patients was 49.7 years (42–64 years), the average follow-up period was 20.4 months (19–22 months). All patients underwent total / subtotal resection of the parotid gland; we used an abdominal dermal fat graft to close the defect. Histological examination of the surgical material revealed a pleomorphic adenoma of the parotid gland in 5 cases; in 2 cases, a ma-
lignant tumor (adenocystic carcinoma and basal cell carcinoma of the salivary glands), which required adjuvant radiation therapy in radical doses. To assess aesthetic and functional results in the recipient and donor areas, we developed and used a questionnaire.

   Results. 6–8 months after the end of treatment, 5 patients completed questionnaires. 4 people indicated complete symmetry of the face, one patient indicated an average depression. 3 patients did not note any pain in the parotid area, 2 patients had minor discomfort that did not cause any problems. Only one respondent noted redness of the face when eating, which did not cause him any problems; the rest of the survey participants did not find these changes. None of the survey participants noted the appearance of sweat on their face when eating.

   Conclusion. The use of dermal fat grafts can improve the aesthetic and functional results of treatment in patients undergoing operations on the parotid glands. This technique is quite easy to use and does not significantly increase the time of surgical intervention. A derma-fat graft does not make it difficult to monitor disease relapses.

   Aim. To evaluate the capabilities of ultrasound using various approaches in determining the depth of invasion of squamous cell carcinoma of the oral cavity and to compare the results obtained with data obtained by the use of other diagnostic methods.

   Materials and methods. In our reserch, ultrasonography was performed on 193 patients with primary malignant tumors of the mobile part of the tongue, floor of the oral cavity and tumors of rare locations (mucous membranes of the lip, cheek, alveolar processes). The age of the patients ranged from 15 to 85 years. In all patients, tumors were squamous cell carcinoma. ultrasound was performed using submandibular, intraoral and transbuccal approaches. ultrasonic data were compared with the results of pathomorphological examination, as well as of X-ray computed tomography and of magnetic resonance imaging with contrast.

   Results. A statistically significantly high correlation was obtained for all ultrasound approaches (submandibular, intraoral and transbuccal) with the depth of invasion of the oral tumor determined pathomorphologically (r = 0.78; r = 0.89; r = 0.93; p <0.001). Ultrasound using all approaches shows statistically significantly better results in determining the thickness of tumors
of the tongue and mouth floor in comparison with X-ray computed tomography and magnetic resonance imaging (p <0.001). All diagnostic methods are characterized by an overestimation of the tumor invasion depth (overdiagnosis) as compared with pathomorphological examination. for exophytic tumors and oral cavity tumors of mixed growth with an exophytic component, the depth of invasion was less than the tumor thickness.

   Conclusion. Ultrasound is an accessible, easily reproducible, radiation-free method, the resolution of which makes it possible to accurately determine not only the depth of invasion of oral tumors, but also the distance from the tumor to the midline of the tongue, that represents an important information when choosing the extent of surgical intervention.

Introduction. Head and neck cancer is the 7th most common malignancy worldwide; squamous cell carcinoma of the oral mucosa are almost a third of tumors of that localization. Metastatic lesions of the neck lymph nodes are an unfavorable prognostic factor for malignant tumors of that location since it is associated with a 50 % decrease in overall survival. In this regard, the detection of metastases to the neck lymph nodes is an important component of high-quality oncological care for patients with that pathology.

Aim. To evaluate the efficiency of sentinel lymph node biopsy in squamous cell carcinoma of cavity of mouth mucosa cT1–2N0М0.

Materials and methods. 72 patients were included in trial at the age from 21 to 74 (mean 57.3) with confirmed squamous cell carcinoma of cavity of mouth mucosa cT1–2N0М0. No evidence of regional metastasis, by preoperative examination, including ultrasound, computed tomography with intravenous contrast was observed. All patients received radioisotope research to determine localization of sentinel lymph nodes, and then biopsy of that nodes was performed. Before obtaining information about the status of the sentinel lymph node, radical neck dissection was not performed. Pathology report with immunohistochemical investigation was performed by pathologist of A. F. Tsyb Medical Radiological Research Center – branch of the National Medical Research Radiological Center, Ministry of Health of Russia.

Results. When assessing efficiency of sentinel lymph node method, true positives results (detection of metastasis in sentinel lymph node) were achieved in 3 (4.17 %) out of 72 cases. Follow up time was from 1 to 69 months. Among those cases, where metastasis in sentinel lymph nodes were not detected, relapse in regional lymph nodes was developed in 3 (4.35 %) out of 69 cases. Radical neck dissection was performed in cases with metastasis in sentinel lymph nodes. The specificity of method was 95 %, the predictive value of a negative result was 0.04.

Conclusion. Sentinel lymph neck node biopsy is an effective method of subclinical locoregional metastases detection in cancer of oral mucosa cT1–2N0M0. In our study of sentinel lymph neck node biopsy, oncological outcomes were comparable to radical neck dissection, with fewer postoperative complications.

Introduction. Malignant tumors of the nasal cavity and sinonasal tract are rare, less than 3 % of all of the head and neck malignant neoplasm. The leading treatment is combined methods with surgery as a first step. However, operation is limited in a locally advanced process due to requires the use of complex reconstructive techniques and removal of aesthetic and functionally important structures. In this regard, the interest of specialists is understandable in use of organ-preserving techniques with comparable oncological results. Intra-arterial chemotherapy has shown high effectiveness in various localizations of malignant neoplasms, so its use in locally advanced tumors of the nasal cavity and sinonasal tract seems promising.

Aim. To evaluate the results of complex treatment of patients with locally advanced cancer of the nasal cavity and sinonasal tract using induction intra-arterial chemotherapy.

Materials and methods. The study included 28 from 2017 to 2023 with locally advanced cancer of the nasal cavity and sinonasal tract underwent TPF induction intra-arterial chemotherapy, followed by radiation or chemoradiotherapy. The primary endpoint of the study was survival, secondary – objective response rate, treatment toxicity and the possibility of organ preservation.

Results. The median follow-up was 19.1 months. We obtained results for all patients of 1-year overall survival – 85.7 % (T3 – 100 %, T4a – 92.7 %, T4b – 55.6 %), and 1-year progression-free survival – 66.7 % (T3 – 75 %, T4a – 71.4 %, T4b – 50 %), respectively. The response rate after intra-arterial chemotherapy was 85.2 %. Overall survival and progression-free survival did not differ significantly between patients with complete response, partial response, and stable disease. However, in patients with a complete response after chemoradiotherapy, 1-year overall survival was 100 % (p = 0.009) and progression-free survival – 90 % (p <0.001). The main side effect in patients in the study was the development of neutropenia (35.7 %), and occurrence of neurological complications was noted in 10.7 %. Of the 35.7 % of patients with tumor orbital invasion, survival with preserved visual function in the first year of life was 80 %; all patients retained vision; as a result of treatment, not a single patient underwent surgery with exenteration.

Conclusion. Induction intra-arterial chemotherapy in treatment of patients with locally advanced cancer of the nasal cavity and sinonasal tract demonstrates high efficiency and a high level of complete responses with a fairly low level of toxicity, and also allows preserve the eye function for the majority of patients.

   The progression of head and neck squamous cell cancer (HNSCC) may be influenced by the characteristics of the local and systemic immune response, including the peculiarities of systemic inflammatory response during surgical interventions. The dependence of the prognosis of cancer patients on the preoperative general somatic status and postoperative complications is demonstrated precisely through the prism of a systemic inflammation development promoting the progression of oncological process. It is necessary to study the interaction of a typical inflammatory reaction and the features of reparative processes to understand the correct treatment strategy for patients with oral cancer in the conditions of the existing oncological process. It was found that chronization of inflammation is associated with m2-macrophage polarization which contributes to the tumor progression. And systemic inflammation indices correlate with treatment results. It is also necessary to identify prognostic factors of postoperative complications that affect the chronization of inflammation. They may include the general somatic and nutritional status of patients, concomitant diseases and indices of systemic inflammation. It is obvious that improving the results of surgical treatment of patients with oral cancer can be influenced by various ways of managing the inflammatory response, including the peculiarities of performing the reconstructive interventions and improving the preoperative general somatic and nutritional status.

   Aim. To perform a retrospective analysis of the results of surgical treatment of patients with anatomically widespread malignant skull base tumors and evaluate the possibility of using various types of closure of skull base defects.

   Materials and methods. The study is based on a retrospective analysis of medical records of 139 patients with midface tumors aged 14 to 77 years, operated from 1995 to 2023. Histological structure of the tumors was different. we divided all methods of reconstruction of midface defects into two groups. In the group 1, plastic closure of the defect was per-
formed using flaps from anatomical areas located close to the defect. In the group 2, reconstruction was performed using flaps from distant anatomical areas.

   Results. In the postoperative period, we did not observe gross cicatricial face deformities, impaired chewing and swallowing functions due to cicatricial contractures of chewing muscles. Titanium mesh for reconstruction was used in 68 (48.9 %) cases. The osteoperiosteal aponeurotic flap was used in 5 cases, of which in 3 (3.8 % of the total number of patients of the 1^st group) – in combination with the temporal muscle. The thoracodorsal flap was used in 62 (44.6 %) patients. various methods of its movement and combination with the anterior dentate muscle were used. In 41 (66.1 %) cases, good cosmetic and functional results were obtained. These indicators correlated with adequate choice of reconstruction method allowing elimination of most of the impaired functions.

   Conclusion. The use of the presented technologies for plastic closure of post-resection defects of various parts of the skull base, including those combined with extensive damage to the midface, leads to leveling of the cosmetic and functional consequences of surgical aggression.

   Introduction. The multikinase inhibitors have demonstrated high clinical efficacy in treatment of the radioiodine refractory differentiated thyroid cancer. At the same time, the inclusion criteria in the studies has reflected a minimum set of characteristics important for beginning of use of these drugs and an approach that takes into account the tumor progression rate (the volume doubling time) in the absence of clinical manifestations of the disease that have made it possible to individualize the start of therapy.

   Aim. To describe and evaluate the barriers and drivers of use the “watch and wait” approach by Russian oncologists in treatment of the radioiodine refractory thyroid cancer.

   Materials and methods. We conducted 35 structured interviews with oncologists observing patients after radioiodine therapy in order to evaluate the “watch and wait” approach. unfortunately, data on use and prevalence of this approach in Russia are limited. The present study involved the use of deductive content analysis as well as analysis of implementation model of clinical guidelines and included investigation of issue of implementation of the “watch and wait” approach to current practice of therapy for radioiodine refractory differentiated thyroid cancer. One of the main tasks was to determine the influence of external factors on the treatment of this category of patients.

   Conclusion. Barriers and drivers of using “watch and wait” approach in the treatment of differentiated radioiodine refractory thyroid cancer are identified at several levels. for wide use of this approach, it is necessary to involve oncologists taking into account their attitude regarding changes in routine practices, patient expectations and to obtain additional data regarding its long-term effectiveness.

   Introduction. The manifestation of oncological alertness during dispensary observation by a dentist is very important. The most accessible options for preventing malignancy of the oral mucosa are sanitation, regular professional oral hygiene, as well as educational work among doctors and the population. However, despite the visual accessibility of tissues and organs of the oral cavity, there is an annual increase in malignant neoplasms in this area. In this case, most patients are diagnosed with a tumor process of the last stage. malignant neoplasms of the head and neck organs require special attention due to high risk of disability even at an early stage.

   Aim. To evaluate a correlation between malignancy of the oral mucosa and the burdened dental status of patients.

   Materials and methods. A controlled study was conducted which included 142 patients with cancer of the oral mucosa without sequential or parallel inclusion of patients in groups. Dental status was assessed at help-seeking stage or during clinical examination, as planned, by evaluation of main dental indices. The morphological diagnosis was established using histological verification.

   Results. The majority of patients with oral tumors had hard dental plaque (81.7 % of cases). The condition of the soft tissues, in addition to presence of the mucous membrane lesion, was characterized by bleeding (69 % of cases). moderate periodontal pathology was detected (19 % of cases). patients with the cavity tumors had an acute traumatic edge of hard tissues (70 % of cases), extensive caries (26 % of cases) and the presence of removable dentures (82 % of cases).

   Conclusion. The values of parameters evaluated in patients in the study with squamous cell carcinoma of the oral mucosa show its relation to aggravation of general somatic status. All patients in the study required dental treatment and training in oral hygiene care.

   Introduction. Squamous cell carcinoma (SCC) of the oral cavity is an aggressive and rapidly progressing disease. The tendency to progression of the tumor process is due to the clinical and pathological characteristics of the patient and the biological characteristics of the tumor. molecular and genetic disorders related with transcriptome level play an important role in tumor progression, which can be used in predicting the outcome of the disease.

   Aim. To identify markers for assessing the risk of the SCC progression.

   Materials and methods. Based on the data of the Cancer genome Atlas database, a bioinformatic search for genes associated with the progression of SCC was performed (11 genes were selected). Then we performed a retrospective analysis of clinical data and histological material from 38 patients with SCC treated at the Scientific Research Institute of Oncology of the Tomsk National Research medical Center of the Russian Academy of Sciences from 2018 to 2021. Fixed samples of tumor tissue were examined. The level of gene expression was determined by real-time quantitative polymerase chain reaction.

   Results. It was shown that decrease in the ST6GAL2 matrix RNA level is associated with presence of lymphogenic metastases and decrease in the CD248 matrix RNA level is associated with the occurrence of relapses.

   Conclusion. Expression level of the ST6GAL2 and CD248 genes can be used as predictors of an unfavorable prognosis of SCC.

   Introduction. Cigarette smoking along with alcohol consumption, infection with human papilloma (HPV) and the Epstein–Barr viruses, is one of the main risk factors for head and neck squamous cell carcinoma. It can also contribute to virus-associated carcinogenesis and affect the clinical and prognostic features of the tumor. Continued smoking at diagnosis of head and neck squamous cell carcinoma is a negative prognostic factor and contributes to reduced patient survival rates.

   Aim. To analyze the smoking status and the effect of etiopathogenesis on molecular and clinical features in patients with oropharyngeal squamous cell carcinoma (OpSCC).

   Materials and methods. In patients with OPSCC, the smoking status and the level of motivation to its cessation were clarified. Immunohistochemical analysis of tumor sections from paraffin blocks from the ThermoScentific immunohis-tosteiner was performed using monoclonal antibodies to estrogen receptors α (ERα), programmed death-ligand 1 (pD-L1), Bcl-2, p53 and p16. The percentage of tumor-infiltrating lymphocytes (TILs) in the stromal component of the tumor (hematoxylin and eosin staining) was also analyzed.

   Results. Of 113 patients with OpSCC, 80 % of patients were current smokers, including 75 % of patients with Hpv-positive tumor status. men with OpSCC were statistically significantly more likely to smoke than women (p = 0.001), as were men with Hpv-positive tumor (p = 0.015). Smoking patients were characterized by a larger size of the primary tumor (T3–4), including those with Hpv (p = 0.015). positive Hpv status of the tumor is associated with autoimmune diseases (autoimmune thyroiditis, psoriasis) (p ˂ 0.05). A high level of TILs is characteristic of smokers, including those with p16+-status (p ˂0.05), but not for all patients with this status. The positive expression of ERα is associated with p16+-status, and the latter is associated with the absence of p53 expression (p ˂0.05). During conservative therapy, tumor regression is associated with the primary tumor size T1–2, p16 + status, female sex, age less than 55 years, TILs level ≥ 57.5 %, pD-L1 expression levels on tumor cells ≥2.2 %, Bcl-2 ≥5 % and ERα ≥65 % (p ˂ 0.05). At the same time, quality of good predictive model for tumor regression showed a TILs level of ≥57.5 % (area under curve, AuC) 0.796; sensitivity 78.6 %; specificity 75 %) and ERα (AuC 0.725; sensitivity 65 %; specificity 83 %). The level of motivation to quit smoking ranged from 1 to 7 points according the 10-point motivation scale in 89 % of respondents. Only 10 patients were ready to quit smoking immediately (10 points on the motivation scale).

   Conclusion. Molecular heterogeneity of OPSCC was revealed, including in the group of p16+-tumors. Correlation of clinical and molecular parameters with response to conservative therapy can be used in planning of primary therapy and earlier use of surgical treatment. The level of motivation to quit smoking in patients with squamous cell carcinoma of the head and neck may be increased by drawing attention to the problem at each doctor’s appointment as well as by informing about how to quit smoking and therapeutic approaches. In unmotivated patients, the concept of reducing the harm of smoking can be used involving the replacement of cigarettes with electronic tobacco heating systems, eliminating the carcinogenic effect of its combustion products.

   Skin cancer is the second most common tumor among non-melanoma malignant skin neoplasms, accounting for 20 % of cases. In the Russian federation in 2022, this pathology was identified in 79,124 people. The peak incidence occurs in the age range of 60–70 years. Considering the increasing life expectancy, the incidence of skin cancer is expected to rise. Despite the fact that regional metastases occur in 0.3–16 % of cases, the risk of metastasis can increase up to 48 % depending on high-risk factors. Since the presence of regional metastases is a key prognostic factor, special attention should be given to preventive interventions in the areas of regional metastasis.

   The article presents the history of development of otorhinolaryngology, a medical service associated with the head and neck tumors, as well as head and neck medical departments. The need for treatment of patients with malignant neoplasms in specialized oncological institutions is shown. Analysis of literature data, doctors’ speeches at various scientific conferences and personal contact with specialists in the head and neck cancers from Russia and countries – former republics of the USSR confirms the need for existence of the head and neck tumor departments.