FIGURE 1.
Making process of Styrofoam. (A) Glue. (B) Bags. (C) Unformed Styrofoam. (D) Making of molded Styrofoam (Individualized head fixation as well as arm fixation as shown in the red circle)
FIGURE 2.
ROI Matching.
CROI = chest wall target; SROI = supraclavicular target
TABLE 1.
Comparison of clinical data between the two groups
| Group | Styrofoam n = 36 | Bracket n = 29 | P-value |
|---|---|---|---|
| Age (x ± s, years) | 48.34 ± 9.58 | 48.90 ± 10.92 | 0.837 |
| Affected Side (n, %) | 0.565 | ||
| Left | 20 (55.6) | 11 (37.9) | |
| Right | 16 (44.4) | 18 (62.1) | |
| Type of operation (n, %) | 0.053 | ||
| Bcs | 7 (16.7) | 9 (31) | |
| Rm | 29 (83.3) | 20 (69) | |
| Stage (n, %) | 0.146 | ||
| II | 7 (19.4) | 4 (13.8) | |
| III | 26 (72.2) | 20 (68.9) | |
| IV | 3 (8.4) | 5 (17.3) |
[i] BCS = Breast Conserving Surgery; RM = Radical Mastectomy
TABLE 2.
Comparison of setup errors of the two fixation methods in the chest wall target area and supraclavicular target area (mm,`x ± s)
| Group | Styrofoam | Bracket | t | P-value |
|---|---|---|---|---|
| CROI (X) | 1.59± 1.47 | 2.05 ± 1.64 | 2.516 | 0.012 |
| (Y) | 1.99 ± 1.46 | 2.10 ± 1.59 | 0.611 | 0.541 |
| (Z) | 1.78 ± 1.47 | 2.00 ± 1.58 | 1.235 | 0.218 |
| SROI (X) | 1.23 ± 0.88 | 1.32 ± 1.16 | 0.620 | 0.536 |
| (Y) | 1.23 ± 1.21 | 1.16 ± 1.17 | −0.445 | 0.657 |
| (Z) | 1.36 ± 1.27 | 1.75 ± 1.55 | 2.003 | 0.046 |
| CRTN (°) | 0.48 ± 0.46 | 0.53 ± 0.43 | 1.033 | 0.302 |
| SRTN (°) | 0.47 ± 0.47 | 0.66 ± 0.59 | 2.760 | 0.006 |
[i] CROI = Chest Wall Target; SROI = supraclavicular target
TABLE 3.
Target volume expansion boundary in the three-dimensional direction in 65 patients in the breast bracket and Styrofoam groups (mm)
| Styrofoam | Bracket | ||||||
|---|---|---|---|---|---|---|---|
| X | Y | Z | X | Y | Z | ||
| Σ Systematic error | CROI | 1.59 | 1.99 | 1.78 | 2.05 | 2.10 | 2.00 |
| SROI | 1.23 | 1.23 | 1.36 | 1.32 | 1.16 | 1.75 | |
| σ Random error | CROI | 1.47 | 1.46 | 1.46 | 1.39 | 1.57 | 1.57 |
| SROI | 0.88 | 1.12 | 1.26 | 0.98 | 1.17 | 1.54 | |
| MPTV | CROI | 5.01 | 5.99 | 5.47 | 6.10 | 6.34 | 6.10 |
| SROI | 3.69 | 3.86 | 4.28 | 3.99 | 3.72 | 5.45 | |
FIGURE 3.
Bar chart of setup error of two fixation methods in chest wall target area.
FIGURE 4.
Box plot of setup error in supraclavicular region of two fixation methods.
FIGURE 5.
Scatter plot of setup error between two groups in different directions. The dark color in the upper figure shows the bracket group, and the light color in the lower figure shows the Styrofoam group. The r-values with P-values < 0.05 are indicated in the figure.
C = chest wall; S = supraclavicular