Trends in pathology in colorectal cancer patients in Serbia 2003-2016

Colorectal cancer (CRC) is a leading cause of morbidity and mortality worldwide, with varying trends in tumor pathology depending on geographic and demographic factors. The aim of this study was to describe trends in tumor pathology in Serbian patients with colorectal cancer (CRC) over a 14-year period, from 2003 to 2016. The study included patients referred from local units to the tertiary center for CRC treatment during the entire observation period, as well as patients diagnosed within the national screening program during the last four years. Resections were performed in 2462 patients (1465 men, 60% and 997 women, 40%) with an average age of 62±12 years, and the incidence was equally distributed between genders. Rectal tumors were noted in 54% of patients, while in 46% of patients tumors were found in the colon (32% in the left and 14% in the right colon). The majority of patients were in an advanced stage of the disease, with only 12% of cases with Dukes A stadium. Patients with early-onset disease represented between 11% and 22% of all cases per year. Among early-onset patients, women were significantly overrepresented (P=0.013), patients were diagnosed at significantly later stages (P=0.033), tumors were significantly less differentiated (P=0.001) and tumors of the right colon were overrepresented (P<0.001). A group of patients who underwent neoadjuvant chemoradiotherapy consisted of 235 men and 88 women with an average age of 60±12 years. Within this group, 20% of patients had a good response, 37% a moderate response, and 43% a poor response. The study has provided valuable insight into trends in tumor pathology in Serbian CRC patients and confirmed the beneficial effects of the introduction of the national screening program.