Outcome of proximal esophageal cancer after definitive combined chemo-radiation: a Swiss multicenter retrospective study

Objective: To report oncological outcomes and toxicity rates, of definitive platin-based chemoradiadiationtherapy (CRT) in the management of proximal esophageal cancer. Methods: We retrospectively reviewed the medical records of patients with cT1-4 cN0-3 cM0 cervical esophageal cancer (CEC) (defined as tumors located below the inferior border of the cricoid cartilage, down to 22 cm from the incisors) treated between 2004 and 2013 with platin-based definitive CRT in four Swiss institutions. Acute and chronic toxicities were retrospectively scored using the National Cancer Institute's Common Terminology Criteria for Adverse Events, version 4.0 (CTCAE-NCI v. 4.0). Primary endpoint was loco-regional control (LRC). We also evaluated overall survival (OS) and disease-free survival (DFS) rates. The influence of patient-and treatment related features have been calculated using the Log-rank test and multivariate Cox proportional hazards model. Results: We enrolled a total of 55 patients. Median time interval from diagnosis to CRT was 78 days (6-178 days). Median radiation dose was 56Gy (28-72Gy). Induction chemotherapy (ICHT) was delivered in 58% of patients. With a median follow up of 34 months (6-110months), actuarial 3-year LRC, DFS and OS were 52% (95% CI: 37-67%), 35% (95% CI: 22-50%) and 52% (95% CI: 37-67%), respectively. Acute toxicities (dysphagia, pain, skin-toxicity) ranged from grade 0 -4 without significant dose-dependent differences. On univariable analyses, the only significant prognostic factor for LRC was the time interval > 78 days from diagnosis to CRT. On multivariable analysis, total radiation dose > 56Gy (p < 0.006) and ICHT (p < 0.004) were statistically significant positive predictive factors influencing DFS and OS. Conclusion: Definitive CRT is a reliable therapeutic option for proximal esophageal cancer, with acceptable treatment related toxicities. Higher doses and ICHT may improve OS and DFS and. These findings need to be confirmed in further prospective studies.