Gallbladder cancer is generally associated with a poor prognosis, being local recurrence the main pattern of failure.To evaluate neoadjuvant chemoradiation as a means to improve the prognosis in gallbladder cancer.Twenty three gallbladder cancer patients were prospectively treated between June 1993 and September 1999 in the Temuco Regional Hospital. Eighteen (82%) patients had subserosal infiltration, while three (13%) had serosal and two (9%) adipose tissue infiltration. Chemotherapy was done with 5-fluorouracil in continuous infusion during 5 days at day 1 and 28 of treatment. Radiotherapy consisted in a total dose of 4500 cGy, divided in 25 sessions. Patients' survival was compared with a series of 19 patients not subjected to chemoradiation, formerly treated at the institution.Twenty patients had hematological problems secondary to the therapy. Leucopenia and thrombocytopenia were the most common toxic effects and eight had leucopenia under 2.0 x 10(3) during the treatment course. Chemoradiation delayed surgical treatment in eight patients. After the chemoradiation protocol, seven patients were excluded from surgical treatment and 14 patients underwent resection. Three of the latter (11%) had liver involvement and four (14%) had lymph node involvement. Among the patients who underwent resection, five are still alive with a follow up of 43.8 months. Treated patients had a worst actuarial survival than subjects not treated with chemoradiation.In this series of patients chemoradiation had no positive effect and a potentially detrimental effect in patients with gallbladder cancer.