Introduction: Approximately 1 in 20 female cancers in Europe is of the endometrium. Endometrial carcinoma is the most common gynaecologic cancer. Considering the fact that an upward tendency has recently been observed in morbidity due to this type of cancer, this is a serious medical problem. Objective: The presented report describes the results of the analysis of selected demographic factors and their effect on the incidence of endometrial cancer. Analysis of the results of treatment of endometrial cancer during 1995-2010 was also an objective of the study. Materials and methods: Based on medical records obtained from the HDR Laboratory of Brachytherapy at the Gynaecological & Obstetrics Clinical Hospital, University of Medical Sciences in Poznan, the results of treatment of patients with endometrial cancer by brachytherapy were analyzed. The analysis covered a group of 400 patients. Results: More than a half of the patients completed their education on the level of elementary or secondary school. Taking into consideration the weight of the patients, it appeared that most women had excessive body weight. Most frequently, concomitant hypertension was observed. Moreover, the age at menarche was 12 and 13. Conclusions: Demographic factors exert a significant effect on the incidence of endometrial cancer. 1. Overweight and obesity are important risk factors of endometrial cancer. 2. A strong relationship is observed between the occurrence of hypertension or diabetes, and the development of endometrial cancer. 3. Women who come from the rural environment and continue to live in this environment are more likely to contract endometrial cancer.