NIJMEGEN, The Netherlands--With 12,000 new cases of esophageal cancer diagnosed every year in the United States, and 5-year postoperative survival rates still hovering under 20%, the need to develop more effective multimodality treatment strategies remains crucial, said David Ilson, MD, of Memorial Sloan-Kettering Cancer Center.
Of the three most extensively explored approaches--preoperative radiotherapy, preoperative chemotherapy, and chemotherapy plus radiotherapy prior to or instead of surgery--preoperative radiotherapy has had the least impact on survival, notwithstanding improved local control, Dr. Ilson said in a presentation at the Sixth EORTC Gastrointestinal Tract Cancer Cooperative Group symposium.
On the other hand, although preop-erative chemotherapy only rarely pro-duces pathologic complete responses, it has yielded clinical response rates in the neighborhood of 50%, exerts no adverse influence on surgery, and has been associated with a trend toward improved survival, he said.
Still more promising may be intensified approaches that combine chemotherapy and radiotherapy, Dr. Ilson said. Surveying phase II trials of 5-fluorouracil (5-FU)- or mitomycin(Drug information on mitomycin) (Mutamycin)-based regimens coupled with radiation doses of 3,000 to 6,000 cGy, he pointed to pathologic response rates as high as 20% to 30% and to 5-year disease-free survival rates reaching 35% to 40% in some studies.
Unfortunately, he said, preliminary results from a small University of Michigan trial have shown no differences in survival between surgery alone vs presur-gical 5-FU, cisplatin(Drug information on cisplatin) (Platinol), and vinblastine(Drug information on vinblastine) plus 4,500 cGy of radiation. Similarly, in an EORTC trial, the combined modality approach appeared to offer no survival advantage over surgery alone.
"Although the pilot studies of preop-erative chemotherapy, with or without radiation, are very encouraging in terms of response and trends in survival," he said, "these approaches remain investigational and need to be validated in the context of controlled phase III studies."
In the nonsurgical setting, he said, chemotherapy and radiation are the definitive treatment, "and we can conclude that they are superior to radiation alone."