Page 144 - SRPSKO DRUŠTVO ISTRAŽIVAČA RAKA

Serbian Association for Cancer Research SDIRSACR

(6.78 vs 21.45; p<0.0001) were also observed in the all-high subgroup. Patients with high-value ratios were younger
(p=0.0162). No difference was observed in terms of gender (p=0.99), BRAF mutation status (p=0.53), the occurrence of
immune-related adverse events (p=0.34) or LDH levels (p=0.16).
Conclusions: Inflammatory ratios are promising and accessible biomarkers that, either alone or combined, could be
incorporated into clinical practice delineating patients who will benefit the most from mono-ICI and those who would
need additional agents or alternative therapeutic approaches.

P50

Validation of an LC-MS/MS method for the determination of imatinib and n-desmethyl imatinib in human
plasma

Milkica Crevar, Branka Ivković

Department of Pharmaceutical Chemistry, Faculty of Pharmacy, University of Belgrade, Belgrade, Serbia

Keywords: drug monitoring, imatinib, LC-MS/MS, metabolite, plasma, validation

Background: Imatinib is a selective tyrosine kinase inhibitor used for the treatment of chronic myeloid leukemia
and other malignancies. Its primary metabolite, N-desmethyl-imatinib, has similar pharmacological properties.
Quantification of both compounds in plasma is essential for therapeutic drug monitoring and pharmacokinetic studies.
In this study, an LC-MS/MS method for the determination of imatinib and N-desmethyl-imatinib in human plasma was
developed and validated.
Materials and Methods: Chromatographic separation was performed on an InfinityLab Poroshell 120 EC-C18
chromatography column (4.6 × 100 mm, 2.7 µm) using a mobile phase consisting of methanol and water with 0.1
% formic acid and 0.2 % ammonium acetate (55:45, v/v). The column temperature was set to 40 °C and the flow
rate of the mobile phase was 700 µL/min. The injection volume was 10 µL. Detection was performed in MRM mode,
monitoring the transitions m/z 494 > 394 for imatinib and m/z 480 > 394 for N-desmethyl-imatinib. The total run time
of the analysis was 5 minutes.
Results: For imatinib, the method showed excellent linearity in the range of 5–500 ng/ml (r = 0.999), with an intra-run
accuracy of 104.59% and an inter-run accuracy of 105%. The precision ranged from 1.4 % to 5.67 % RSD, depending
on the concentration. The LOD and LOQ were 1.2 ng/mL and 5 ng/mL, respectively. The recovery was 91%. For
N-desmethyl-imatinib, linearity was also satisfactory (r = 0.998), with a within-run accuracy of 103.13% and a between-
run accuracy of 105%. The precision ranged from 1.2% to 13.8% RSD. The LOD was 1.8 ng/ml and the LOQ was 5 ng/
ml. The recovery was 89%.
Conclusions: The validated LC-MS/MS method is selective, accurate and precise and is suitable for routine analysis of
imatinib and its metabolite in human plasma in accordance with ICH guidelines.

P51

Prevalence of head and neck cancer in Serbia

Nikolina Božović , Drago Jelovac , Svetlana Jovanović , Vesna Bjegovic-Mikanovic , Maja Milošević Marković 1
3
2
1
1
1Clinic of Maxillofacial Surgery, School of Dental Medicine, University of Belgrade, Belgrade, Serbia
2Department of Public Health, School of Dental Medicine, University of Belgrade, Belgrade, Serbia
3Institute of Social Medicine, School of Medicine, University of Belgrade, Belgrade, Serbia

Keywords: head and neck neoplasms, mouth neoplasms, incidence, mortality, epidemiology, Serbia

Background: Head and neck cancers represent a widely prevalent group of malignancies worldwide. Globally, they
rank 16th in terms of incidence and 15th in terms of mortality. The aim of this study was to determine the descriptive
epidemiological characteristics of head and neck cancers (ICD-10: C00–C13, C32) in Serbia during the period from 1999
to 2022.

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