24 April 2025
: Case report 
Arm-Behind-the-Back Position for Breast Cancer Radiotherapy in Patients with Lupus Erythematosus and Shoulder Arthropathy: A Case Report
Unusual setting of medical care
Shoki Nakamura ABCDEF 1,2, Kota Fujii
ABCDEF 1*, Mami Sakai CDEF 3, Keisuke Sakai DE 1, Hideki Hanazawa DE 1, Keisuke Nishimura DE 4, Kenji Notohara BDE 5, Kazushige Yamaguchi DE 6, Satoshi Itasaka ABCDE 1
DOI: 10.12659/AJCR.946674
Am J Case Rep 2025; 26:e946674
Table 1. Detail of the plans in the regular supine and the arm-behind-the-back position.
| Regular supine position | Arm-behind-the-back position | |
|---|---|---|
| Size of irradiation field [cm×cm] | 8.9×17.0 | 8.4×17.0 |
| Beam gantry angle [degrees] | 126 and 304 | 130 and 308 |
| Beam collimator angle [degrees] | 15 | 8 |
| Dmean of PTV [Gy] | 42.56 | 42.56 |
| D2 of PTV [Gy] | 44.72 | 44.80 |
| D50 of PTV [Gy] | 42.79 | 42.79 |
| D98 of PTV [Gy] | 39.91 | 38.16 |
| HI | 0.112 | 0.155 |
| Central lung distance [cm] | 2.1 | 0.6 |
| Dmean of left lung [Gy] | 2.44 | 1.30 |
| Dmean of heart [Gy] | 1.50 | 1.08 |
| PTV – planning target volume; D – mean dose; DX – minimum dose received by the hottest X% of the volume; HI – homogeneity index (=(D-D)/D). | ||