Neoadjuvant therapy for gastrointestinal cancers.

Neoadjuvant (primary) chemotherapy is an attractive concept for upper GI tract malignancies and to a lesser extent rectal cancer to increase local control, as well as to destroy micrometastasis. Endoscopic ultrasonography for esophageal, gastric, and rectal cancers is a new tool that may allow identification of appropriate high-risk patients for such investigational approaches. In esophageal cancer, radiation therapy alone has probably been supplanted by combined concurrent systemic chemotherapy and radiation. Phase III trials of chemotherapy prior to operation are currently underway. Phase II trials of neoadjuvant chemotherapy are underway in gastric cancer. In rectal cancer, while the use of postoperative adjuvant chemotherapy plus radiation is firmly established, more recent data suggest that there may be less toxicity with preoperative treatment, and in selected patients may result in increased potentially curative resection rates.