Induction chemio-radiotherapy for squamous cell carcinoma of the thoracic esophagus: long-term results of a phase 2 study

BACKGROUND: This study was done to evaluate the results of the combined use of chemo- and radiotherapy before surgery in a group of patients with squamous cell esophageal carcinoma after a median follow-up period of more than 5 years. METHODS: Between June 1987 and January 1995, 111 patients with squamous cell carcinoma of the thoracic esophagus were submitted to a preoperative course of radiotherapy (3000 cGy) and chemotherapy (cisplatin and 5-FU) before surgery in the First Division of General Surgery at the University of Verona. RESULTS: The neoadjuvant treatment was completed in 90.9% of the cases (101/111). After an average of 29 days, 87 patients underwent surgery (operability rate: 78.3%) and, of these, 80 underwent esophagectomy (resectability rate: 91.9%). Histopathologic studies showed no residual disease in the specimen (T0) in 17 cases (21.2%), only microscopic clusters of neoplastic cells within the esophageal wall (Minimal Residual Disease, MRD) in 14 cases (17.5%) and in 5 cases the tumor did not extend beyond the submucosal layer (T1). The median overall survival time of the 111 patients who were eligible for the study protocol was 14 months, and the 2- and 5-year survival rates were 32.0% and 17.5%, respectively. Kaplan-Meier determination of survival showed a statistically significant difference between the good responders (T0, T1, and MRD) to the neoadjuvant treatment and the remaining cases. The 2- and 5-year survival rates were 50.3% and 34.9%, respectively, in the good responder group compared with 26.7% and 10.7%, respectively, in the other cases, with a median survival time of 24 months vs. 13 months, respectively. CONCLUSIONS: The neoadjuvant treatment showed promising results, especially in the group of patients that had a good response. The identification of these patients may be the key to selecting which patients should be submitted to preoperative radio- and chemotherapy