1. Department of Radiation Oncology, Xijing Hospital, Fourth Military Medical University, No. 127 West Changle Road, Xi'an, 710032 China.
2. Department of Biostatistics, The University of Texas MD Anderson Cancer Center, Houston, TX, 77030;
3. Department of Radiation Oncology, The University of Texas MD Anderson Cancer Center, 1515 Holcombe Blvd., Unit 097, Houston, Texas 77030, USA.
* Both of the authors contributed equally to this work.
Purpose: The reported data of elderly ESCC are rather limited and there is a lack of information to guide treatment decisions for elderly patients with esophageal cancer. This study aims to identify the efficacy and factors for optimal treatment approaches for elderly esophageal squamous cell carcinoma (ESCC) treated with radiotherapy (RT) alone or concurrent chemoradiation (CCRT).
Methods: This study included 184 I-III elderly ESCC patients aged ≥70 years treated by oral single agent CCRT (sCCRT) or double agents CCRT (dCCRT) or RT alone at a single institution in China. RT was delivered with Intensity Modulated Irradiation Therapy (IMRT) or Volumetric-Modulated Arc Therapy (VMAT). Sequential or simultaneous integrated boost (SIB) approach was applied for GTV dose escalation. Toxicities were evaluated by criteria of Radiation Therapy Oncology Group. Statistical analyses were performed on survival and failure patterns.
Results: At a median follow-up time of 15.5 months, the 2- and 3-year estimated overall survival (OS) were 43.5% and 35.2%, respectively. T and N stage, GTV dose (cutoff value 56Gy), simultaneous integrated boost (SIB) technique and CCRT were significant predictors for the outcomes. sCCRT was significantly associated with higher OS, LRFS, and DFS when compared with RT alone and no difference was observed between sCCRT and dCCRT. 44% patients experienced treatment failure, among whom 65.4% developed local failure. 81.3% local failure occurred in GTV and 70.6% regional failures occurred out of radiation field. dCCRT was the only independent prediction factor for grade ≥ 2 neutropenia and gastrointestinal reactions compared with sCCRT and RT alone. No significant difference of toxicities was observed between sCCRT and RT alone.
Conclusions: Our results demonstrated that CCRT in elderly patients had significant survival benefit compared to RT alone, especially using Single oral agent. sCCRT had less toxicities compared to dCCRT, and the toxicity was similar to RT alone. GTV dose ≥ 56 Gy and SIB technique were optimal approaches for radiotherapy.
Keywords: elderly esophageal squamous cell carcinoma (ESCC), failure pattern, prognostic factor, concurrent chemoradiation (CCRT), toxicities