Abstract Primary adenocarcinoma of the vermiform appendix is a rare clinical condition. It usually presents as an acute abdominal process or as a mass in the right lower quadrant. The gross pathologic and microscopic characteristics of this disease are the same as for colon carcinoma and carry a serious prognosis. We report a case of a 64-year old male patient presenting symptoms of acute appendicitis. The patient underwent laparoscopic appendectomy that revealed a severely inflamed appendix. Histopathological examination has shown that it was a poorly differentiated, high grade adenocarcinoma invading the periappendicular fat. According to the histopathological findings, a right hemicolectomy was further advised and performed. Right hemicolectomy is the generally recommended method of treatment for invasive adenocarcinoma of the appendix.