['Current radiation therapy capacities in Serbia and most of Eastern Europe are heavily lagging behind population needs. The primary study aim was assessment of direct costs of cancer medical care for patients suffering from cancer with assigned radiotherapy-based treatment protocols. Identification of key cost drivers and trends during 2010-2013 comparing brachytherapy and teleradiotherapy was a secondary objective of the study.', "Retrospective, bottom-up database analysis was conducted on electronic discharge invoices. Payer's perspective has been adopted with a 1-year long time horizon. Total sample size was 2544 patients during a 4-years long observation period (2010-2013). The sample consisted of all patients with confirmed malignancy disorder receiving inpatient radiation therapy in a large university hospital.", 'Diagnostics and treatment cost of cancer in the largest Western Balkans market of Serbia were heavily dominated by radiation therapy related direct medical costs. Total costs of care as well as mean cost per patient were steadily decreasing due to budget cuts caused by global recession. The paradox is that at the same time the budget share of radiotherapy increased for almost 15% and in value-based terms for €109 per patient (in total €109,330). Second ranked cost drivers were nursing care and imaging diagnostics. Costs of high-tech visualizing examinations were heavily dominated by nuclear medicine tests.'] Does radiation therapy remain the key cost driver of oncology inpatient treatment?