Adjuvant therapy for noncolorectal cancers.
Review
Overview
abstract
Cancers of the esophagus, stomach, and pancreas account for 11% of American cancer deaths and have a high case fatality rate. For esophageal cancer, the superiority of chemoradiotherapy rather than radiotherapy alone as a nonsurgical management was reaffirmed by a large pattern-of-care study in the United States. The study of preoperative chemoradiotherapy followed by surgery continues, with the investigation of newer chemotherapeutic agents combined with radiotherapy in an attempt to improve the therapeutic index of therapy. Trials attempting to intensify chemoradiotherapy treatments have included the addition of postoperative chemotherapy, the addition of brachytherapy, and the escalation of radiotherapy dose above the standard dose of 50.4 Gy. Neither brachytherapy nor an increase in external beam radiotherapy dose has been proven to improve local tumor control or patient survival. Adjuvant chemotherapy alone may have an impact on patient survival in one preliminary report, despite the results of earlier trials that failed to show a benefit for adjuvant chemotherapy alone. In the adjuvant treatment of gastric cancer, a meta-analysis of adjuvant chemotherapy trials suggested a survival benefit for adjuvant chemotherapy compared with surgery alone; however, preliminary reports of two large adjuvant chemotherapy trials using cisplatin-based chemotherapy failed to improve survival compared with surgery alone. The large Intergroup Trial 116, comparing surgery alone to surgery followed by postoperative fluorouracil, leucovorin, and radiotherapy, indicated a significant survival benefit for postoperative chemoradiotherapy. Postoperative chemoradiotherapy is the new standard of care for high-risk resected gastric cancer. Ongoing and future trials will address the inclusion of newer chemotherapeutic agents, the use of preoperative chemotherapy and radiotherapy, and the use of intraperitoneal therapy. In the adjuvant treatment of pancreatic cancer, clinical trials continue to evaluate the role of fluorouracil and radiotherapy, the use of preoperative chemoradiotherapy, and the incorporation of new therapeutic agents.
