Treatment of carcinoma of the esophagus with 5‐fluorouracil and recombinant alfa‐2a‐interferon

Background. Combinations of 5‐fluorouracil (5FU) and recombinant alfa‐2a‐interferon (IFN) are synergistic in vitro and have demonstrated activity in colorectal carcinoma, renal cell carcinoma, and urothelial tumors. Methods. A Phase II trial of the combination of 5FU, 750 mg/m² daily × 5 followed by weekly bolus therapy, and IFN, 9 MU subcutaneously three times per week, was initiated in patients with esophageal carcinomas. Patients were required to have biopsy‐proven squamous cell or adenocarcinoma of the esophagus, locally advanced or metastatic disease beyond the scope of surgical resection, and adequate performance status, renal, hepatic, and bone marrow function. Results. Twenty‐one patients were enrolled; one patient was inevaluable for response because he had received prior chemotherapy, but was evaluated for toxicity. Eleven patients had metastatic disease, and 10 had locally advanced disease. Thirteen patients had squamous cell carcinoma and 8 adenocarcinoma. Toxicities were acceptable with no serious diarrhea and only two cases of serious stomatitis, although a greater than expected incidence of neurologic toxicity was observed. There were five responders (25%) including two patients with advanced or locally advanced disease rendered pathologically free of disease. One patient, initially considered surgically unresectable, was able to undergo a total thoracic esophagectomy after responding to treatment with 5FU/IFN, at which time only a single microscopic focus of carcinoma in situ was found. She remains alive and free of disease at 18+ months. A second patient who presented with metastatic disease and nearly complete obstruction of the esophagus regained normal swallowing function after treatment with 5FU/IFN; rebiopsy of all lesions revealed the patient to be pathologically free of disease. He survived over 2 years. Conclusions. This regimen employing a single cytotoxic agent has activity in esophageal carcinoma. Strategies employing biochemical modulation deserve additional investigation in the treatment of esophageal carcinoma.