Between January 1983 and August 1998, a total of 18 patients (14 men, 4 women; median age 58 years, range 36-75 years) with primary adenocarcinoma of the duodenum underwent surgical therapy. Main clinical symptoms were upper abdominal pain (61%), weight loss (44%) and anaemia (38%). The tumors were resectable in 10 patients (56%), and eight Whipple operations and two segmental duodenectomies were performed. Tumor classification according to the TNM system was pT2 (n = 2), pT3 (n = 6) and pT4 (n = 2). In eight patients, local lymph nodes were tumor positive (pN1), and in two patients synchronous liver metastases were excised. The UICC stage of the resected tumors was: stage I (n = 1), stage II (n = 1), stage III (n = 6) and stage IV (n = 2). In irresectable cases (n = 8), the patients underwent palliative (n = 6) or explorative (n = 2) operations. With no operative mortality, overall morbidity was 22% (4/18). Patients' survival was 90%, 66.7% and 53.3%, respectively, at 1, 3 and 5 years after resection. None of the patients with irresectable tumors survived longer than 25 months. Survival was significantly better for the resection group (P = 0.0027). Due to the often unspecific symptoms, the diagnosis of duodenal adenocarcinoma is frequently established at advanced tumor stages, resulting in a low resectability rate. Radical surgical resection of the tumors, however, is able to provide a more favorable prognosis for duodenal carcinoma than for other periampullary tumors.