[Chemoradiotherapy for lung, esophageal, and uterine cervix cancer]

Some early cancer is completely cured by radiation therapy alone. In many advanced cases, however, local control rates are low with radiation therapy. Chemoradiotherapy has recently become a standard treatment to improve therapeutic-results. The objective of chemoradiotherapy is to improve local tumor control, to control potential systemic metastases, or both. In chemoradiotherapy, drugs effective against primary tumors are selected, platinum compounds often being key drugs. Regarding the timing of radiation and chemotherapy, three patterns are possible: sequential, concurrent, and alternating. In the sequential pattern, the severity of acute toxicity decreases; however, an extended total therapeutic period can lower the antitumor effect. In the concurrent pattern, the maximum antitumor effect is expected because of the simultaneous action of radiation and chemotherapy, but the severity of acute toxicity is intensified to the extent that treatment withdrawal or dose reduction may be required. In the alternating pattern, radiation therapy is quit transiently during chemotherapy. As a result, the irradiation period is extended so that the antitumor effect might be reduced. To explore the methods and results of chemoradiotherapy in each disease, this paper also reports on the results of meta-analysis and randomized trials. Although chemoradiotherapy is not recommended for all patients, it is considered to be more appropriate than radiation therapy alone in patients who have good performance status and adequate organ function.