The 5-year survival for pancreatic cancer is usually less than 5%, and no treatment has demonstrated consistent effect on patient survival and disease-related symptoms. Early studies with gemcitabine suggested a modest antitumor activity with significant improvement in disease-related symptoms. This phase II study reports the activity of gemcitabine on 33 consecutive patients with unresectable pancreatic carcinoma. Twenty-three patients had metastatic and 10 locally advanced unresectable disease. Twenty-six patients had not received any previous treatment and seven had received first-line chemotherapy with 5-fluorouracil. Gemcitabine 1,000 mg/m2 was administered intravenously in 30 minutes in the first cycle once weekly for up to 7 weeks followed by 1 week rest; then in subsequent cycles, once weekly for 3 of every 4-week cycle. Four patients obtained partial response (12%). Fifteen patients (45%) had stable disease with a median duration of 32 weeks (range: 16-75 weeks), and 14 patients experienced progressive disease. Median duration of response was 34.5 weeks (range: 19-50 weeks). Median survival was 33 weeks (range: 2-91 weeks). All 4 responding patients and 14 of 15 (93%) patients with stable disease had improvement in performance status and decrease in daily analgesic requirement. Toxicity was mild and mainly consisted of moderate and rapidly reversible myelosuppression. We conclude that gemcitabine chemotherapy was very well tolerated and determined a significant clinical improvement with modest antitumoral activity in patients with advanced pancreatic cancer.