INTRODUCTION: Adjuvant radiotherapy is an integral part of the current treatment of many malignant tumours. However, this mode of treatment does not provide only benefits in the sense of lowering the risks of recurrence, but it is also associated with many undesirable side effects, from which one of the most serious is the development of secondary malignancies. CASE REPORT: The author describes a case report of 77 years old woman who underwent hysterectomy with bilateral adnexectomy and pelvic lymphadenectomy for uterine carcinoma pT1bN0M0, G1 in 2005. Adjuvant external radiotherapy with the dose 45Gy and brachytherapy 3x4Gy followed. Subsequently the patient was followed at the department of gynecology, which referred her in January 2015 with a quickly growing tumour of the skin and subdermal tissue in the hypogastric area, where previous radiation had been applied. Its excision was indicated with the diagnosis of suspected uterine carcinoma metastasis, but subsequent histological evaluation confirmed angiosarcoma. Despite negative resection margins the tumour quickly recurred and disseminated. CONCLUSION: Angiosarcoma as a side effect of irradiation is described increasingly more often nowadays. The vast majority of cases are related to the treatment of breast carcinoma. Its prognosis is very poor and therapeutic possibilities are limited. Surgical excision with negative margins remains the mainstay of the treatment. It is necessary to keep this diagnosis in mind and patients undergoing radiation treatment should be followed over a long period. KEY WORDS: angiosarcoma.