ABSTRACT
Objective:
To analyze whether involved-field irradiation (IFI) was associated with improved
survival and reduced
treatment-related adverse events compared with elective nodal irradiation (ENI) in
Chinese patients with
esophageal squamous cell carcinoma receiving
radiotherapy.
Methods:
Literature review was conducted from CNKI, Wanfang Data,
PubMed, Embase, Web of
Science and Cochrane Central databases (until July 31, 2022). Relevant data were collected according to the inclusion and exclusion criteria. Primary outcomes included overall
survival (OS) rate and
treatment-related adverse events.
Secondary outcomes included
progression-free survival (PFS) rate and local control rate (LCR).
Risk of
bias was assessed using the Cochrane
Risk of
Bias tool. The quality of the results was assessed by using the meta
analysis of Evidence Evaluation and Grading of Recommendations, Assessment, Development and Evaluations (GRADE)
methods.
Results:
A total of 7 articles with 918
patients were included of which 465 received IFI and 453 received ENI. The 1-, 2-, 3-and 5-year OS rates in the IFI group were not significantly different from those in the ENI group (1-year OS rate RR=1.00, 95% CI=0.94-1.07, P=0.97, high certainty; 2-year OS rate RR=1.01, 95% CI=0.90-1.13, P=0.90, high certainty; 3-year OS rate RR=0.86, 95% CI=0.71-1.05, P=0.14, high certainty; 5-year OS rate RR=0.76, 95% CI=0.42-1.37, P=0.36, low certainty). In the IFI group,
patients with ≥grade 2 acute
radiation esophagitis ( RR=0.71, 95% CI=0.58-0.87, P=0.001, high certainty), ≥grade 3 acute
radiation esophagitis ( RR=0.39, 95% CI=0.24-0.64, P<0.001, high certainty) and ≥grade 2 acute
radiation pneumonitis ( RR=0.72, 95% CI=0.52-0.99, P=0.04, high certainty) were significantly lower compared with those in the ENI group. However, no significant differences were observed in the
incidence of ≥grade 3 late
radiation esophagitis, ≥grade 3 acute
radiation pneumonitis and ≥grade 3 late
radiation pneumonitis between two groups. No significant differences were noted in the 1-, 2-, 3-PFS rates and LCR between two groups.
Conclusions:
For
Chinese patients with
esophageal squamous cell carcinoma, IFI and ENI yield
similar efficacy in terms of OS, PFS and LCR. However, IFI has a lower
incidence of ≥grade 2 acute
radiation esophagitis, ≥grade 3 acute
radiation esophagitis and ≥grade 2 acute
radiation pneumonitis than ENI.