Radiation Therapy for Esophageal Cancer: Improving the Therapeutic Ratio

Recent studies in nonmetastatic cancer of the esophagus have shown improved local control and survival by the use of combined chemotherapy and radiation therapy compared with radiation only. This has been achieved by accepting an increased incidence of acute side effects, usually mucositis or myelosuppression, secondary to the concurrent therapy. Local tumor resistance or progression has been a major problem, occurring in approximately half of patients following chemoradiation. This article reviews alternative radiation therapy techniques that could allow dose intensification, thereby improving tumor control without causing unacceptable acute or chronic treatment complications, ie, improving the therapeutic ratio. Total dose escalation using brachytherapy, or conventional or altered fractionation are discussed. Improvements in radiation treatment planning, including patient positioning, modifications in normal tissues encompassed within the target volume, and three-dimensional treatment planning are potential methods of decreasing the normal tissue complications that should be explored.