• American Cancer Society — Select 'Choose a cancer topic' then select 'Bile Duct Cancer'
• MEDLINEplus: Cholangiocarcinoma Overview
• National Cancer Institute
• OncoLink — Enter 'Bile Duct Cancer' in the 'Quick Search' box

Carcinoid

• American Cancer Society — Select 'Choose a cancer topic' then select 'Gastrointestinal Carcinoid Tumors'
• The Carcinoid Cancer Foundation, Inc.
• National Cancer Institute
• OncoLink — Enter 'Gastrointestinal Carcinoid Tumor' in the 'Quick Search' box

Colorectal

• American Cancer Society — Select 'Choose a cancer topic' then select 'Colon and Rectum Cancer'
• CANCERCare®: Advances in the Treatment of Colorectal Cancer (pdf)
• Colon and Rectal Cancer Treatment Guidelines for Patients
• Colon, Rectal and Anal Cancer: Ask NOAH
• Colon Cancer Alliance
• MEDLINEplus: Colorectal Cancer
• National Cancer Institute
• OncoLink
• People Living with Cancer

Esophagus

• American Cancer Society — Select 'Choose a cancer topic' then select 'Esophagus Cancer'
• MEDLINEplus: Esophageal Cancer
• National Cancer Institute
• OncoLink
• People Living with Cancer

Gallbladder

• American Cancer Society — Select 'Choose a cancer topic' then select 'Gallbladder Cancer'
• National Cancer Institute
• OncoLink

Liver

• American Cancer Society — Select 'Choose a cancer topic' then select 'Liver Cancer'
• The Liver Cancer Network: Allegheny Hospital
• MEDLINEplus: Liver Cancer
• National Cancer Institute
• OncoLink
• People Living with Cancer

Pancreas

• American Cancer Society — Select 'Choose a cancer topic' then select 'Pancreatic Cancer'
• The Johns Hopkins Medical Institutions Pancreas Cancer Home Page
• The Lustgarten Foundation for Pancreatic Cancer Research
• MEDLINEplus: Pancreatic Cancer
• Pancreatic Cancer (NCI)
• Islet Cell Carcinoma (NCI)
• The National Pancreas Foundation
• OncoLink
• Pancreatic Cancer Action Network
• Pandreatica.org
• People Living with Cancer

Small Intestine

• National Cancer Institute
• OncoLink

Stomach

• American Cancer Society — Select 'Choose a cancer topic' then select 'Stomach Cancer'
• MEDLINEplus: Stomach Cancer
• National Cancer Institute
• OncoLink
• People Living with Cancer

Digestive Cancers: General

• Holden Comprehensive Cancer Center
• Iowa Consortium for Comprehensive Cancer Control (ICCCC)
• American College of Gastroenterology
• The American Gastroenterological Association

Cancer Website Directories

• Association of Cancer Online Resources

Clinical Trials

• National Cancer Institute
• Cancer Trials Help
• Center Watch
• Clinical Trials.gov
• PhRMA
• NIH Clinical Center