Clinical complete responders to definite chemoradiation or radiation therapy for oesophageal cancer: predictors of outcome

Background: To identify predictors of long-term outcome for patients with clinical complete response (cCR) after definite chemoradiotherapy (CRT) or radiation therapy (RT) for oesophageal cancer (EC). Methods: In this retrospective study, we reviewed the files of all patients from our institution that underwent definitive RCT or RT for EC, from January 1998 to December 2003. Among 402 consecutive patients with EC, 110 cCR responses were observed, i.e. without evidence of tumour on morphological examination of the biopsy specimens, 8 to 10 weeks after radiation. Baseline patient and tumour characteristics were as follows: male = 98/110, median age = 60, squamous histology = 103/110, tumour site (upper/middle/lower third) = 41/50/19, weight loss none/<10%/>= 10% = 36/45/29, dysphagia grade 1/2/>= 3 = 30/14/66. Patients were staged according to endosonography and/or computed tomography. There were 9 stage I, 31 stage IIA, 15 stage IIB, 41 stage III, 6 stage IV. Post treatment nutritional characteristics were as follows: weight loss during treatment none/< 10%>= 10% = 35/38/37, remaining dysphagia grade 1/2/>= 3 = 54/24/32. Univariate and multivariate analyses were performed using log-rank and Cox proportional hazards models, and survival curves were estimated using the Kaplan-Meier method. Results: During follow up (median: 6 [0.4-9.8] years), 16 patients had salvage surgery. Median OS was 2.5 years, and 5-year OS was 33.5%. Histological type, stage, age, gender, and treatment characteristics had no significant impact on outcome. The risk of death was increased two-fold for patients with grade >= 3 dysphagia after treament (HR = 1.9 [1.2-3.1], p = 0.007). Weight loss >= 10% during treatment also negatively affected outcome (HR = 1.8 [1.0-3.2], p = 0.040). Conclusion: One EC patient among 3 with cCR after definite CRT/RT is still alive at 5 years. Variables related to reduced OS were: remaining significant dysphagia after treatment and weight loss >= 10% during treatment.