[Mixed adenoneuroendocrine carcinoma (MANEC) of the gastrointestinal tract].

Mixed adenoneuroendocrine carcinoma (MANEC) is a rare tumour of the gastrointestinal tract composed of adenocarcinoma and neuroendocrine carcinoma. This pathologic diagnosis was recently defined by the WHO in 2010. The tumour may appear in various levels of the digestive tract including the oesophagus, stomach, colon and appendix. Biological behaviour of MANEC seems to be quite unpredictable and the prognosis uncertain. The disease may also mimic "simple" carcinoma. Only several tens of cases have been reported so far.Our first case was diagnosed as gastric adenocarcinoma mimicking early gastric cancer in a 47 years old male. The second case was diagnosed incidentally in the appendix of a 69 years old female after operation for gynaecologic cancer. The disease was localised in both patients; the patients underwent radical surgical resections.Treatment options have not been standardised yet, but aggressive therapeutic measures are recommended. The patients may benefit from multimodal anticancer therapy.Key words: mixed adenoneuroendocrine carcinoma - MANEC - gastric cancer - appendiceal cancer.