Table 2.
Comparison of a previous study6 with our study
| Previous study6 | Our study | |
|---|---|---|
| Institution | Single institution | Single institution |
| Patients | 12 patients | six patients |
| Fasting | At least 4 h before CT and RT | Abstained from one meal before CT and RT |
| BH-CT images at planning CT | Three sets | Three sets |
| BH method | Visual feedback method | Visual feedback method |
| CTV | Whole stomach | Whole stomach |
| PTV | CTV plus 0.5–1 cm | CTV plus 0.8 cm |
| Prescribed dose | 30 Gy (1.5–2 Gy/fraction); D95% prescribing methoda | 30.6 Gy (1.8 Gy/fraction); isocenter-prescribing methodb |
| Daily CT for BH-IGRT | In-room CT | CBCT |
| Observer for the study | One observer | Two observersc |
| Mean V95% of daily CTV (%) | 98.5 | 97.2 |
| Mean V95% of daily PTV (%) | 94.9 | 91.0 |
BH, Breath-hold; BH-CT, Breath-hold computed tomography; BH-IGRT, Breath-hold image-guided radiotherapy; CBCT, Cone-beam computed tomography; CT, Computed tomography; CTV, Clinical target volume; PTV, Planning target volume; RT, Radiotherapy; V95%, Percentage of volume receiving ≥95% of the prescribed dose.
*>95%of the PTV was covered by the prescription dose.
a
>95%of the PTV was covered by the prescription dose.
b
The prescribed dose was delivered to the isocenter.
c
Considering interobserver variations, daily CTV was delineated individually by two radiation oncologists as observers 1 (ST) and 2 (TN) in our study.