Prognostic Value Of Her2, Pd-L1 And Ret Mrna Expression In Salivary Gland Tumor.

e18534 Background: The objective of our study was to evaluate the cytologically, morphologically and IGH detection of salivary gland (SGT), expression of HER2 and PD-L1, CPS and determine these associations with patient survival. Methods: The study included 59 patients with a confirmed diagnosis of salivary gland cancer (stage II-IVA) by cytology, morphology and IGH analyses. After that HER2, in tumor and tumor infiltrating immune cell PD-L1 expression (with CPS) was determined using IHC-testing. RET mRNA gene expression calculated with using real-time PCR. Results: Aspiration biopsies results: only in 22 (37.29%) cases the malignant tumor was cytologically confirmed. An IHC study showed the proportion of high-grade tumors significantly exceeded 3.82 times the proportion of low-grade tumors (p < 0.00001). Low grade SGT were 2 times more often recorded by morphological studies (p = 0.0172), high grade SGT - 1.37 times more often by IHC study (p = 0.0176). HER2 expression: (0) – 29(60.42%), (1+) – 11(22.92%), (2+) – 4(8.33%), (3+) – 4(8.33%). Median OS HER2-neg pp was 170.25±24.49 mo (95% CI 125.25-218.26), median OS of 8 pp (16.33%) with HER2 (2+,3+) was 41,00 mo (95%CI 4.50-72.00) (HR 0,07; 95% CI 0,01-0,38; p = 0.00715). Median PFS HER2-neg pp was 168.00 mo (95% CI 75.00-168.00), median PFS of 8 pp (16.33%) with HER2 (2+,3+) was 19,00 mo (95%CI 1.00-31.00) (HR 0,23; 95% CI 0.04-1.22; p = 0.01641). PD-L1 expression was: in tumor cells 0-90% in 11/49 pp (22.45%), in immune cells 0-50% in 26/49 pp (53.06%) (p = 0.0006). CPS was 0-100, median CPS 5 (95% CI 0.03-10.00). Median OS pp with CPS > 1 was 72.00 mo (95% CI 19.5-72.00); with CPS < 1 hasn’t yet been achieved (OR 0.26; 95% CI 0.09-0.75; p = 0.0124). RET mRNA expression was detected in 13 of 48 cases (27.08%). The expression level ranged from 0 to 0.205. The median PFS in the RET mRNA-positive pp was 168.00 mo (95% CI 16.00-168.00) and tended to exceed the median TTP in the RET mRNA-naive patient group. Conclusions: The results suggest that the understanding the receptor status of salivary gland cancer can be effective prognostic factors.