Radiation and chemoradiation therapy for esophageal adenocarcinoma.
The aims of preoperative chemoradiation therapy (preop-CRT) for esophageal adenocarcinoma are to reduce incomplete local resection (R1,R2), local and systemic recurrences that are reported in up to 30% of patients who undergo surgery alone. Phase II studies of preop-CRT, with radiation doses in the 40-50 Gy range, and concurrent chemotherapy with 5-fluorouracil (5-FU)-cisplatin +/- paclitaxel, or cisplatin-paclitaxel, have reported subsequent RO resection rates of 80%-100%, with tumor sterilization achieved in 8%-49% of cases, and consequently improved local control. New chemotherapy regimens omitting 5-FU have reduced the incidence of severe esophagitis, unplanned hospitalization, with comparable efficacy. Among three randomised trials that compared preop-CRT to surgery alone, one shown a debatable survival advantage. Reducing local recurrence rates lead to a switch to more distant failures, and increasing the radiation dose beyond 45 Gy appears to be of little value. However, it should be remembered that preop-CRT has associated toxicity, and may increase postoperative mortality. Novel strategies, which include induction with chemotherapy followed by preop-CRT, and for radiation therapy, three dimensional conformation techniques, image fusioning, and improved definition of treatment volumes, are still considered experimental and should be tested in specialized centers.