Biliopancreatic diversion with duodenal switch (BPD-DS) is a well-known emerging open procedure that appears to be as effective as other bariatric operations and has been shown to provide excellent long-term weight loss. Therefore we looked at the safety and efficacy of the laparoscopic BPD-DS procedure compared to open BPD-DS in superobese patients (body mass index >60). A retrospective study of 54 superobese patients (body mass index >60) was carried out from July 1999 to June 2001: laparoscopic BPD-DS in 26 patients and open BPD-DS in 28 patients. Median preoperative body weight was 189.8 kg (range 155.1 to 271.2 kg) in the laparoscopic BPD-DS group and 196.5 kg (range 160.3 to 298.9 kg) in the open BPD-DS group. Median body mass index was 66.9 kg/m(2) in the laparoscopic group and 68.9 kg/m(2) in the open group. The two groups were compared by means of the unpaired t test, which yielded the following results: Major morbidity occurred in six patients (23%) in the laparoscopic BPD-DS group and in five patients (17%) in the open BPD-DS group (P = 0.63). There were two deaths in the laparoscopic BPD-DS group (7.6% mortality) and one death (3.5% mortality) in the open BPD-DS group (P = 0.51). Preoperative comorbidity was improved in eight patients in the laparoscopic BPD-DS group and two patients in the open BPD-DS group (P < 0.02). Laparoscopic BPD-DS is a technically feasible procedure that results in effective weight loss similar to the open procedure. However, both open and laparoscopic BPD-DS procedures are associated with appreciable morbidity and mortality in the superobese population. Additional studies are needed to determine the best surgical treatment for superobesity.