Definitive chemoradiation for patients with inoperable and/or unresectable esophageal cancer: locoregional recurrence pattern

A locoregional recurrence after definitive chemoradiation (dCRT) for patients with inoperable or unresectable esophageal cancer occurs in about 50% of the patients and is a major cause of failure with a poor prognosis. The aim of this study was to determine the pattern of locoregional recurrence and its prognostic factors after dCRT in order to search for improvements in radiation treatment. We retrospectively reviewed 184 patients treated with external beam radiotherapy (50.4 Gray/28 fractions), combined with weekly concurrent paclitaxel and carboplatin. Locoregional recurrences were defined by clinical signs of recurrent or progressive disease, combined with progression on computed tomography/positron emission tomography-computed tomography scan, or suspicious endoscopic findings and/or histological proof of recurrence. The site of locoregional recurrence was analyzed with respect to the borders of the radiation fields. After a mean follow up of 22.8 months, 76 patients (41%) had evidence of locoregional recurrence. The 3-years locoregional recurrence-free rate was 45%. The majority of locoregional recurrences occurred within 12 months, nearly all within 24 months. The majority of these patients failed at the site of the primary tumor (86%). Infield locoregional recurrences at the site of the lymph nodes only occurred in 1% compared with 57% at the site of the primary tumor only. Outfield locoregional lymph node recurrences occurred in 22%, without infield recurrence occurred in only 4% of all patients. The 1-, 3-, and 5-year overall survival was 65%, 28%, and 21%, respectively. The current analysis demonstrates that a locoregional recurrence after dCRT occurs in 41% of the patients, the majority at the site of the primary tumor. These data suggest a benefit of dose intensification of the primary tumor, but not at the site of the lymph nodes. Higher radiation doses should be assessed with prospective trials.