AUTHOR=Chen Xianyan , Zhang Yingjie , Zhou Xiaojuan , Wang Min , Na Feifei , Zhou Lin , Xu Yong , Zou Bingwen , Xue Jianxin , Liu Yongmei , Gong Youling 

TITLE=Involved-field irradiation or elective-nodal irradiation in neoadjuvant chemo-radiotherapy for locally-advanced esophageal cancer: comprehensive analysis for dosimetry, treatment-related complications, impact on lymphocyte, patterns of failure and survival

JOURNAL=Frontiers in Oncology

VOLUME=13

YEAR=2023

URL=https://www.frontiersin.org/journals/oncology/articles/10.3389/fonc.2023.1274924

DOI=10.3389/fonc.2023.1274924

ISSN=2234-943X

ABSTRACT=<sec><title>Purpose</title><p>To compare the differences between involved-field irradiation (IFI) and elective nodal irradiation (ENI) in selecting the optimal target area for neoadjuvant chemoradiotherapy (nCRT) in patients with locally advanced esophageal squamous cell carcinoma (LA-ESCC).</p></sec><sec><title>Materials and methods</title><p>We retrospectively analyzed 267 patients with LA-ESCC, of whom 165 underwent ENI and 102 underwent IFI. Dosimetry, treatment-related complications, pathological responses, recurrence/metastasis patterns, and survival were compared between the two groups.</p></sec><sec><title>Results</title><p>The median follow-up duration was 27.9 months. The R0 resection rates in the IFI and ENI groups were 95.1% and 92.7%, respectively (<italic>p</italic>=0.441), while the pathological complete response (pCR) rates were 42.2% and 34.5%, respectively (<italic>p</italic>=0.12). The ENI group received higher radiation doses to the heart (HV<sub>30</sub>:23.9% <italic>vs</italic>. 18%, <italic>p</italic>=0.033) and lungs (LV<sub>30</sub>:7.7% <italic>vs.</italic> 4.9%, <italic>p</italic>&lt;0.001) than the IFI group. Consequently, the ENI group showed a higher incidence of grade 2 or higher radiation pneumonitis (30.3% <italic>vs.</italic> 17.6%, <italic>p</italic>=0.004) and pericardial effusion (26.7% <italic>vs.</italic> 11.8%, <italic>p</italic>=0.021) than the IFI group. Post-operation fistulas were observed in 3 (2.9%) and 17 cases (10.3%) in the IFI and ENI groups, respectively (<italic>p</italic>=0.026). In the multivariate analysis, smoking, positive lymph node involvement (pN+), and anastomotic fistula were independent predictors of overall survival (OS). The pN+ patients exhibited a greater propensity for recurrence compared to pN- patients, especially in the first year of follow-up (6.67% <italic>vs.</italic> 0.56%, <italic>p</italic>=0.003).</p></sec><sec><title>Conclusion</title><p>The ENI group had a higher incidence of radiation-induced adverse events compared to the IFI group, likely due to the higher radiation doses to normal tissues. Considering the similar disease-free survival (DFS) and OS rates in the two groups, IFI may be suitable for nCRT in patients with LA-ESCC, although further prospective studies are warranted.</p></sec>