Relevance. The inflammatory process and endogenous intoxication of the patient’s body has a negative impact on the course of many malignant neoplasms, including salivary gland cancer.The objective of the study was to determine the influence of some factors of systemic inflammation and endogenous intoxication in salivary gland cancer.Methods and materials. A prospective study included the data of 59 patients with salivary gland cancer. The influence of peripheral blood parameters and relative indicators characterizing systemic inflammation on overall and disease-free survival was assessed.Results. As a result of the multivariate analysis, it was revealed that an increase in the level of the relative number of peripheral blood neutrophils by more than 60.08 % increases the risk of death in patients from salivary gland cancer by 3.90 times (p=0.0456; HR 3.90: 95 % CI 1.03–14.79). The level of the absolute number of peripheral blood lymphocytes, not exceeding 1.49x109 /l, increases the risk of disease progression by 8.72 times (p=0.0002, R 8.72: 95 % CI 2.78–27.28).Conclusion. Individual factors of systemic inflammation and endogenous intoxication, it is advisable to evaluate at the stage of planning the primary treatment of patients with salivary gland cancer, in order to determine the prognosis of the disease and optimize the choice of tactics for the primary treatment of patients.

651 Background: The objective of this work was to evaluate the molecular and genetic features of the NET gastrointestinal tract. Genomic sequencing of 30 tumor samples of the latest generation was carried out and the data obtained were evaluated. Methods: In total, 30 tumor blocks of patients with gastrointestinal NET were tested by the new generation sequencing (NGS) method. The following genes were analyzed: ATM, ATR, BARD1, BRCA1, BRCA2, BRIP1, CDH1, CDK12, CHEK1, CHEK2, EPCAM, FANCL, MLH1, MSH2, NBN, NF1, PALB2, PMS2, RAD51B, RAD51C, RAD51D, RAD54L, STK11, TP53, POLE, KRAS, NRAS, BRAF, EGFR, ERBB2, PIK3CA, MET ex14, BAT25, BAT26, NR21, NR24, MONO27, KIT, PDGFRA, Pi3Ca. Preparation of libraries for sequencing was carried out using NimblGen SepCapEZ Choice. Sequencing was performed on the Illumina MiSeq device. Results: In the study cohort of patients whose tumor blocks were sent for examination by the NGS method, there were more women – 19 (63.3%) than men – 11 (36.7%). When analyzing the age of patients, it should be noted that among all age groups, elderly patients predominated (60-74 years according to the WHO classification, 2016) – 12 (40%). In the majority of patients – 10 (33.3%) – the primary tumor focus was localized in the pancreas, in 6 (20%) patients it was primarily affected stomach, 7 (23.3%) – small intestine. Other parts of the gastrointestinal tract were affected much less frequently: the colon – in 1 (3.3%) patients. According to the division according to the degree of differentiation of gastrointestinal NET10 tumors had a degree of differentiation G1 (33.3%), 16 -G3 (54.3%), 4– G3 (13.3%). In the tumor sample of a patient with gastric NET G1 (Ki 67 = 2%), POLE mutations were found: c.2276G > A, p.R759H and CHEK2: c.470T > C, p.I157T. Also, mutations MLH1: c.199G > A, p.G67R BRCA1: c.1881 were found in the tumor sample of another patient with gastric NET G2 (Ki 67 = 7%). Conclusions: To improve the survival rates of patients, it is worth paying special attention to the molecular genetic study of the NET gastrointestinal tract. It is molecular genetic profiling that can become the basis for building more individualized algorithms for treating patients. The results of this study allow us to count on the fact that when conducting a study on a larger cohort of patients with gastrointestinal NET, it is possible to obtain results that will expand our knowledge of this nosology and allow us to supplement the already available information about prognosis factors and predictors of response to treatment.

435 Background: The aim of the present study was to determine to the effect of HER2, dMMR, PD-L1 status in the primary tumor and in metastasis to the regional lymph node of GC patients. Methods: A total of 44 patients with primary loco-regional (N+) gastric adenocarcinoma were recruited, and two formalin-fixed paraffin-embedded (FFPE) tumor-containing blocks of each patient (one block with primary tumor and one block with metastasis to the regional lymph node)were selected for HER2, dMMR, PD-L1 (CPS) immunohistochemical (IHC) assay. Clinicopathological characteristics were recorded, and intertumoral heterogeneity of HER2, dMMR, PD-L1 IHC expression was determined. Results: The study included 19 women and 25 men, 30 patients had Laurén’s intestinal type of cancer, 14 had a Laurén’s diffuse type. In 5 patients (11.4%) overexpression of Her-2 neu was detected, and heterogeneity was detected in all five cases: in three patients with HER2 overexpression in the primary tumor, no overexpression was detected in the metastasis to the regional lymph node, in two cases overexpression was detected in the metastasis, while no overexpression was observed in the primary tumor. 2 patients showed signs of dMMR (4.5%), in one case, heterogeneity in dMMR status was also revealed: signs of dMMR in the primary tumor and its absence in regional metastasis (pMMR). Assessment of PD-L1 status was carried out using the CPS formula. Ten patients (22.7%) had a negative PD-L1 status (CPS=0) both in the primary tumor and in regional metastasis. Positive PD-L1 status in the primary tumor: in 24 patients CPS= 0-5 (54.5%), in 5 patients CPS= 5-10 (11.4%) and 5 patients CPS= 10 or more (11.4% ). Positive PD-L1 status in regional lymph node metastasis: in 24 patients CPS= 0-5 (54.5%), in 5 patients CPS= 5-10 (11.4%) and in 5 patients CPS= 10 or more ( 11.4%). In 5 cases (11.4%) marked heterogeneity in PD-L1 status between the primary tumor and its regional metastasis (1 case with dMMR heterogeneity). Conclusions: The research findings in this paper indicate that the intertumoral heterogeneity of HER2 overexpression is common in GC patients, We highly recommend multi-block HER2 assessment for accurate diagnosis of GC. Given the rarity of status detection dMMR, a study in a larger number of patients is required, however, our data also confirm the presence of heterogeneity in dMMR status, and probably the possibility of metastasis of a more aggressive pMMR clone. Heterogeneity in PD-L1 status is quite rare and amounted to only 11.4%, which also has important practical significance.

e18059 Background: We investigated the efficacy and safety of docetaxel + cisplatin (DC) induction chemotherapy vs TPF in patients with locally advanced HNSCC. Methods: Under our observation there were 22 patients in HNSCC (63,6% men and 36,4% women, aged 43 to 74 years (58.7±9.4 (95% CI 55.0-62.4)). The control group consisted of 18 patients (72,2% men and 27,8% women, aged 43 to 73 years (53.9±8.8 (95% CI 49.6-58.3). Both groups were comparable in terms of location, stage (III-IVA) and tumor differentiation. The patients of group 1 received DC (docetaxel 75 mg/m2 + cisplatin 75 mg/m2; q3w) as induction chemotherapy (ICT), while patients in the control group received TPF. Results: The planned number of ICT cycles (No. 3) in group 1 was received by 100% pts. and in the control group - 77.78% pts. (p = 0.02). At the control assessment according to RECIST 1.1, PR was registered in 77.3% pts. of group 1 vs 55.5% pts. in control group (p = 0.14), SD - in 22.7% vs 33.3: (p = 0.45), PD was registered only in patients of the control group - in 11.2% (p = 0.11). The frequency of registration of AEs: diarrhea gr.1-3 - 9.1% pts. group 1 vs 33.3% of pts. the control group (p = 0.06), nausea gr.1 -2 - 9.1% vs 22.2% (p= 0.25), asthenia gr. 1-2 - 4.5% versus 16.7% (p = 0.20), anemia gr. 1-2 - 9.1% vs. 16.7% (p = 0.47), neutropenia gr. 3-4– 4.5% versus 16.7% (p = 0.20). Reduction of doses of cytostatic up to 50% was performed in 4.5% pts. in group 1 and 16.7% pts. in the control group (p = 0.20). Conclusions: Induction chemotherapy in DC mode may be an effective and safe regimen in certain groups of patients with HNCH (for example, in patients with contraindications to 5-FU infusions, as well as in patients with high-risk HHNH for alternative surgical treatment or concurrent CRT as initial treatment of localized and locally advanced HNSCC.