The aim of this paper is to critically analyze and evaluate the impact of human capital education on the economic growth of enterprises in the Republic of Serbia, with a special focus on theoretical and empirical aspects of the relationship between investments in knowledge and organizational productivity. Starting from modern economic and managerial paradigms that treat human capital as one of the main carriers of competitive advantage, the paper problematizes the levels and structure of the labor force education in Serbia, as well as the degree of compliance between educational profiles and the requirements of the modern business environment. Methodologically, the research relies on the analysis of relevant literature, statistical data and results of previous studies, in order to identify key correlations between the educational level of employees and growth indicators at the level of individual enterprises. The obtained findings indicate a strong positive impact of continuous investment in education and professional development on innovation, efficiency and financial performance of enterprises. The conclusion points to the need for a systemic approach to human capital development, which implies more intensive cooperation between educational institutions, the state and the private sector in order to create a dynamic and flexible labor market, capable of responding to the challenges of the modern knowledge-based economy.

Introduction: Sarcomas are rare tumors that account for less than 1% of malignant tumors in adults. Primary leiomyosarcoma (LMS) of the inferior vena cava (VCI) is a very rare tumor with an incidence of <1/100,000 of all malignant diseases in adults. This paper presents the case of a woman with LMS of the VCI who underwent radical tumor resection with vascular reconstruction. Case report: A 71-year-old woman went to the doctor because of painless hematuria. As part of the diagnostic evaluation, in addition to US and CT examination of the abdomen, CT angiography with 3D reconstruction was performed. The conclusion of the radiologist was that the described tumor mass first corresponds to a primary LMS of the VCI VCI that propagated laterally into the lumen of the left renal vein, while the right renal artery was infiltrated by the tumor. The patient was presented to the multidisciplinary team at the Institute for Oncology and Radiology of Serbia (IORS), which decided for operative treatment. The tumor was completely removed en bloc with the right kidney, right suprarenal gland and the confluence of the left renal vein into the VCI. The VCI was reconstructed with a graft with end-end anastomosis, while the left renal vein was implanted in the graft with end-side anastomosis. Conclusion: LMS of the VCI is an extremely rare tumor. Surgical resection of the tumor and the involved blood vessel with negative resection margins is the only therapeutic option that improves survival. Very often, in addition to complicated vascular reconstructions, surgery also includes multivisceral resections, in order to achieve the best possible therapeutic effect.

Background/Objectives: Multiple primary malignancies (MPMs) are defined as the occurrence of two or more independent primary tumors in the same patient, histologically distinct and not of metastatic origin. Patients treated for Hodgkin’s lymphoma (HL) carry an increased risk of developing secondary malignancies, especially after chemotherapy and radiotherapy. The synchronous occurrence of breast and kidney carcinoma in this population is extremely rare. Methods: We present a 41-year-old female patient with a history of HL treated at the age of 23 with ABVD chemotherapy and supradiaphragmatic radiotherapy. Results: During staging for a newly diagnosed breast tumor (ER+/PR+/HER2+, pT1cN0), an incidental renal mass was identified and histologically confirmed as clear cell renal cell carcinoma (pT1aNxMx, G2). A multidisciplinary team performed simultaneous partial breast resection with sentinel lymph node biopsy and nephrectomy. The postoperative course was uneventful, and adjuvant systemic therapy was initiated according to oncological guidelines. Conclusions: Synchronous malignancies in HL survivors pose a clinical challenge, as they must be distinguished from metastatic disease and require coordinated therapeutic planning. Risk factors include prior radiotherapy, chemotherapy, genetic predisposition, and family history. This case highlights the importance of long-term surveillance of HL survivors, particularly young women, due to their elevated risk of secondary malignancies. Synchronous breast and kidney carcinomas after HL therapy are extremely rare and demand an integrated multidisciplinary approach. Early recognition and coordinated therapy are crucial for optimizing outcomes and contributing to a better understanding of the etiology and pathogenesis of multiple primary malignancies.

Lynch syndrome (LS) is the most common hereditary colorectal cancer (CRC) syndrome, caused by germline pathogenic or likely pathogenic variants (PV/LPV) in mismatch repair (MMR) genes. Data on the spectrum of LS-associated variants in Slavic populations, including Serbia, remain limited. Given the high burden of CRC and endometrial cancer and the limited implementation of hereditary CRC screening, characterizing the spectrum of germline variants in clinically selected high-risk individuals is important for improving genetic testing strategies, risk assessment, and clinical management. Between 2018 and 2025, 176 individuals underwent germline testing for hereditary CRC syndrome based on the Amsterdam/Bethesda criteria, validated LS risk prediction models, and/or family history (FH). Next-generation sequencing (NGS) was performed using the Illumina TruSight Hereditary Cancer Panel, and variants were classified according to American College of Medical Genetics and Genomics and Association for Molecular Pathology (ACMG/AMP) guidelines. PV/LPVs in MMR genes were identified in 27/176 (15.3%) and were associated with positive FH of LS-related tumors (p = 0.0001). Most PV/LPVs were identified in MLH1 (10.2%), followed by MSH2 (4.0%) and MSH6 (1.1%), with no PV/LPVs identified in PMS2. Additionally, no pathogenic sequence-level EPCAM variants detectable by the applied panel-based NGS approach were identified. Recurrent MLH1 variants were observed in multiple families, and two previously unreported MLH1 variants were identified. This first systematic analysis of a clinically selected high-risk Serbian cohort provides novel data on the spectrum of LS-associated variants in this referral population, demonstrates the predominance of MLH1 variants, and supports broader implementation of genetic testing, tumor screening, and genetic counseling.