Aim: The detailed review of patterns of failure in this report was undertaken to identify the continuing obstacles to the successful management of oesophageal cancer, and to establish whether there is a case to compare definitive chemo-radiation (Def-CR) and surgery for patients with squamous cancer in a randomized controlled trial.
Materials and methods: First and subsequent sites of failure were reviewed in 274 patients treated with Def-CR using two cycles of cisplatin, infusional fluorouracil and 60 Gy; and 92 patients with limited chemo-radiation (CR), using one cycle and 35 Gy, followed by surgery (CR-Surg). All were treated on prospective non-randomized trials run by the Trans-Tasman Radiation Oncology Group between 1985 and 1999. Failure patterns were analysed using competing risks methodology, and pre-treatment variables predicting survival were identified by proportional hazards modelling.
Results: Site, stage, performance status and gender were independently predictive of survival following Def-CR. Local failure was evident in 42.3% of patients, but distant failure in isolation occurred in an additional 18.1%. Lowest rates of local and distant failure at 5 years (29.9% and 26%) occurred in patients with squamous cancer (SCC) located in the upper-third, whose 5-year survival was also the most favourable (49.2%). Survival was least favourable in patients with adenocarcinoma (AC) in the lower two-thirds (18.1%) due to higher rates of local (51.5%) and distant (36.1%) failure. Local failure occurred in 31.5% of patients undergoing CR-Surg but distant failure in isolation was observed in a further 34.7%. Outcomes were least favourable in patients with AC of the lower-third in whom 57.7% failed distantly and 5-year survival was 3.8%. Response to pre-operative chemo-radiation was also strongly predictive of outcome. Patients with no residual cancer in the resection specimen had the lowest rates of local (0%) and distant (16.7%) failure and the best survival (64.9%). Survival in patients with residual cancer in nodes, however, was extremely poor (3.5%) with distant failure occurring in 66.7%.
Conclusion: The concurrent administration of chemotherapy with radiotherapy seems to have improved loco-regional control and has exposed distant failure as an obstacle to further improvements in outcome. Site, histological subtype, gender and response to chemo-radiation may predict biological differences in oesophageal cancer (OC) that influence outcome. A good case for a randomized comparison between Def-CR and CR-Surg in patients with SCC in the lower two-thirds exists.