RESUMEN
We performed a retrospective analysis of tumours of the kidneys and the lower urinary tract diagnosed at the Institute of Pathology, Faculty of Medicine, Ss. Cyril and Methodius University, Skopje, Macedonia, in a two-year period (2010-2011), with the aim of highlighting the main morphological characteristics and to present the statistical features of these tumours. All the cases were diagnosed on paraffin sections from surgical specimens routinely stained with H&E, and immunohistochemically with a panel of monoclonal antibodies. The analysis revealed a total of 755 cases, of which 166 (14%) were located in the kidney including the renal pelvis, and 649 (86%) were tumours of the urinary bladder. Twelve of the renal tumours (11.3%) were benign, and the rest were malignant tumours. Most of them were adenocarcinomas (n=77; 72.6%) and 17 cases (16%) were transitional cell carcinomas originating from the renal pelvis. The analysis of the lower urinary tract tumours showed a strong prevalence of malignant urothelial tumours (96%), with a male to female ratio of almost 4:1. Low grade morphology was a predominant feature (71.7%) and 51 cases (22.9%) were of high grade. The percentage of urothelial tumours of the kidney in our series is higher than in most of the reported series, which should lead to an expanded analysis.