[Tumor markers in gastrointestinal cancer and its clinical significance].

The clinical usefulness of tumor markers was discussed in gastrointestinal cancer. SCC antigen (subfraction of TA-4) was useful marker in esophageal squamous cell cancer, but was not so helpful in cancer treatment. CEA and CA19-9 were also available as tumor markers of gastric and colorectal cancers, but extremely increased levels were found in only advanced but in early cancer. There was no significant correlation between CEA and CA19-9 so the combination assay of a few kinds of tumor markers, especially CEA and CA19-9 were helpful in cancer treatment.