| Title |
Volumetric and dosimetric comparison of organs at risk between the prone and supine positions in postoperative radiotherapy for prostate cancer
|
|---|---|
| Published in |
Radiation Oncology, April 2018
|
| DOI | 10.1186/s13014-018-1023-0 |
| Pubmed ID | |
| Authors |
Subaru Sawayanagi, Hideomi Yamashita, Mami Ogita, Tomoki Kiritoshi, Takahiro Nakamoto, Osamu Abe, Keiichi Nakagawa |
| Abstract |
The aim of this study was to evaluate the effects of patient positioning on the volume of organs at risk (OARs) in or near the planning target volume (PTV) and the dose distribution in adjuvant or salvage radiotherapy for prostate cancer after prostatectomy. Seventeen patients who received intensity-modulated radiation therapy (66 Gy in 33 fractions) as adjuvant or salvage therapy after prostatectomy were evaluated. All patients underwent CT scans in both the prone (on a belly board) and supine positions. The target volumes and OARs were delineated on each CT series. The planning target volume (PTV) was extended in every direction to generate the PTV + 0.5 cm, PTV + 1 cm, PTV + 2 cm, PTV + 3 cm, and PTV + 4 cm values. The volumes of the OARs overlapping with the PTV and the extended target volumes in the prone and supine position were compared using the Wilcoxon signed-rank test. Dose-volume histogram (DVH) parameters in the prone and supine position were compared using the paired t-test. The mean overlapping volumes of the small intestine for each of the PTV values were as follows (prone position vs. supine position [mean ± SD]): PTV, 1.5 ± 5.5 cm3 vs. 7.9 ± 15.7 cm3 (P = 0.028); PTV + 0.5 cm, 2.6 ± 8.9 cm3 vs. 12.1 ± 22.6 cm3 (P = 0.028); PTV + 1 cm, 3.5 ± 11.4 cm3 vs. 17.1 ± 29.8 cm3 (P = 0.028); PTV + 2 cm, 5.6 ± 14.5 cm3 vs. 26.8 ± 46.9 cm3 (P = 0.028); and PTV + 3 cm, 9.0 ± 17.4 cm3 vs. 36.5 ± 63.2 cm3 (P = 0.019), respectively. Some of the overlapping volumes of the rectum and bladder were significantly smaller in the prone position. On the other hand, when the target volume was extended by ≥2 cm, the overlapping volumes of the femurs were significantly larger in the prone position. V15 of the rectum and mean dose and V65 of the bladder were significantly lower in the prone position. This study indicated that the volumes of the small intestine, rectum, and bladder in or near the PTV decreased when the patient was placed in the prone position on a belly board in postoperative radiotherapy for prostate cancer. The dose distribution seemed superior in the prone position to the supine position. |
X Demographics
The data shown below were collected from the profile of 1 X user who shared this research output. Click here to find out more about how the information was compiled.
Geographical breakdown
| Country | Count | As % |
|---|---|---|
| Cyprus | 1 | 100% |
Demographic breakdown
| Type | Count | As % |
|---|---|---|
| Members of the public | 1 | 100% |
Mendeley readers
The data shown below were compiled from readership statistics for 27 Mendeley readers of this research output. Click here to see the associated Mendeley record.
Geographical breakdown
| Country | Count | As % |
|---|---|---|
| Unknown | 27 | 100% |
Demographic breakdown
| Readers by professional status | Count | As % |
|---|---|---|
| Researcher | 4 | 15% |
| Other | 3 | 11% |
| Student > Bachelor | 3 | 11% |
| Student > Ph. D. Student | 2 | 7% |
| Student > Master | 2 | 7% |
| Other | 3 | 11% |
| Unknown | 10 | 37% |
| Readers by discipline | Count | As % |
|---|---|---|
| Medicine and Dentistry | 5 | 19% |
| Nursing and Health Professions | 4 | 15% |
| Biochemistry, Genetics and Molecular Biology | 2 | 7% |
| Physics and Astronomy | 2 | 7% |
| Agricultural and Biological Sciences | 1 | 4% |
| Other | 1 | 4% |
| Unknown | 12 | 44% |
Attention Score in Context
This research output has an Altmetric Attention Score of 1. This is our high-level measure of the quality and quantity of online attention that it has received. This Attention Score, as well as the ranking and number of research outputs shown below, was calculated when the research output was last mentioned on 19 April 2018.
All research outputs
#20,481,952
of 23,043,346 outputs
Outputs from Radiation Oncology
#1,693
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Outputs of similar age
#288,175
of 327,033 outputs
Outputs of similar age from Radiation Oncology
#30
of 47 outputs
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