Table 3.
Risk factors for developing severe RIL in EC patients, as determined via multivariate analysis.
| First Author/Year | Ref. | Dosimetric Factors ab | Others a | Non-Significant Factors b |
|---|---|---|---|---|
| Xu H/2021 | [16] | Larger PTV, higher heart V10, higher lung V10 | Lower baseline ALC, lower ECOG performance status | Sex, smoking history, alcohol history, tumor location (upper vs. middle/distal), clinical N stage (N0–1 vs. N2–3), lung V5, lung V20, MLD, MHD, VB V10, mean VB dose |
| Liu M/2021 | [15] | Higher EDIC, higher mean dose, higher V20 of TVB | Chemotherapy regimen (CRT vs. RT alone) | V5 and V10 of TVB, RT dose (<60 vs. ≥60 Gy) |
| Wang X/2020 | [17] | Larger PTV, higher heart V10 | Higher clinical stage, lower baseline ALC | Tumor length, lung V5, lung V10, lung V20, lung V30, lung V40, lung mean dose, heart V5, heart V30, heart V40, heart mean dose |
| So T/2020 | [32] | Larger PTV, higher EDIC | Lower baseline ALC | The number of courses of chemotherapy (5 courses vs. fewer than 5 courses) |
| Zhou X/2019 | [22] | Larger PTV | Distal EC, tumor length > 5 cm, older age | MLD |
| Zhang E/2019 | [23] | Heart V15 > 73%, TVB V5 > 72%, body V10 > 18%, aorta V5 > 93% | Lower baseline TLC | Total lung V5 > 50%, spleen V20 > 45% |
| Li Q/2019 | [19] | Higher radiation dose (>40 Gy) | Distal EC, tumor length > 5 cm | Age, alcohol history, dose per fraction > 2.0 Gy, IMRT vs. 3D-CRT, clinical TNM stage (II vs. III), pretreatment ALC (<1.8 vs. ≥1.8 × 109/L) |
| Fang P/2018 | [34] | Higher mean body dose | Higher clinical stage, no smoking at diagnosis | Age, tumor histology, tumor differentiation, tumor location, tumor size, RT modality, induction chemotherapy or chemotherapy type between the groups |
| Davuluri R/2017 | [21] | Higher mean body dose | Concurrent Taxane/5-FU vs. platinum/5-FU | Age, comorbidities, tumor characteristics (location, length, stage, histology, differentiation), surgery, RT modality, induction chemotherapy |
Abbreviations: PTV—planning target volume; TVB—thoracic vertebrae; ECOG—Eastern Cooperative Oncology Group; CRT—chemoradiation therapy; RT—radiotherapy; ALC—absolute lymphocyte count; TLC—total lymphocyte count; Distal EC—distal esophageal cancer; 5-FU—5-fluorouracil; IMRT—intensity-modulated radiation therapy; 3D-CRT—three-dimensional conformal radiation therapy; MLD—mean lung dose; MHD—mean heart dose; VB—vertebral body. a Factors with 2 or more significant results are in bold; b Vx—percentage of the total lung, heart, or VB volume receiving more than x Gy.