Does prone positioning reduce small bowel dose in pelvic radiation with intensity-modulated radiotherapy for gynecologic cancer?

2003 ◽  
Vol 57 (1) ◽  
pp. 230-238 ◽  
Author(s):  
Mustafa Adli ◽  
Nina A Mayr ◽  
Heather S Kaiser ◽  
Mark W Skwarchuk ◽  
Sanford L Meeks ◽  
...  
Keyword(s):  
Small Bowel ◽  
Gynecologic Cancer ◽  
Intensity Modulated Radiotherapy ◽  
Prone Positioning ◽  
Pelvic Radiation ◽  
Intensity Modulated

scholarly journals Evaluation of Small Bowel Motion and Feasibility of using the Peritoneal Space to Replace Bowel Loops for Dose Constraints during Intensity-Modulated Radiotherapy for Rectal Cancer

2020 ◽  
Author(s):  
Siyuan Li ◽  
Yanping Gong ◽  
Yongqiang Yang ◽  
Qi Guo ◽  
Jianjun Qian ◽  
...  
Keyword(s):  
Rectal Cancer ◽  
Small Bowel ◽  
Supine Position ◽  
Intensity Modulated Radiotherapy ◽  
Ct Scans ◽  
Intensity Modulated ◽  
Dose Volume ◽  
Dose Constraint ◽  
Bowel Motion ◽  
Peritoneal Space

Abstract Background The goal of this study was to assess small bowel motion and explore the feasibility of using peritoneal space (PS) to replace bowel loops (BL) via the dose constraint method to spare the small bowel during intensity-modulated radiotherapy (IMRT) for rectal cancer. Methods A total of 24 patients with rectal cancer who underwent adjuvant radiotherapy were selected. Weekly repeat CT scans from pre-treatment to the fourth week of treatment were acquired and defined as Plan, 1W, 2W, 3W, and 4W. BL and PS contours were delineated in all of the scans. Two IMRT plans called P PS and P BL were designed on Plan CT using two dose PS and BL constraint methods, respectively, and then copied to CT 1~4W. The shift%, dose volume, and NTCP of the small bowel in P PS and P BL during treatment were evaluated. Results Overall, 109 sets of CT scans from 24 patients were acquired, and 218 plans were designed and copied. The PS and BL volumes were 1339.28 cc and 250.27 cc. The BL and PS shift% V 15 was 28.48% and 11.79% ( p =0.000), which was less in the prone position than in the supine position (25.24% vs 32.10%, p =0.000; 9.9% vs 14.85%, p =0.000). On all of the CT scans, most P PS small bowel dose volumes were less than from P BL . V 15 was 170.07 cc vs 178.58 cc ( p =0.000), and they had a significant correlation. The NTCP of chronic and acute side effects from P PS was significantly less than P BL (2.80% vs 3.00%, p =0.018; 57.32% vs 58.64%, p =0.000). Conclusions This study indicated that small bowel motion may lead to uncertainties in its dose volume and NTCP evaluation during IMRT for rectal cancer. The BL movements were significantly greater than PS, and the prone position was significantly less than the supine position. Using PS instead of BL can spare the small bowel. V 15 <830 cc is the dose constraint standard.

scholarly journals Evaluation of Small Bowel Motion and Feasibility of using the Peritoneal Space to Replace Bowel Loops for Dose Constraints during Intensity-Modulated Radiotherapy for Rectal Cancer

2020 ◽  
Author(s):  
Siyuan Li ◽  
Yanping Gong ◽  
Yongqiang Yang ◽  
Qi Guo ◽  
Jianjun Qian ◽  
...  
Keyword(s):  
Rectal Cancer ◽  
Small Bowel ◽  
Supine Position ◽  
Intensity Modulated Radiotherapy ◽  
Ct Scans ◽  
Intensity Modulated ◽  
Dose Volume ◽  
Dose Constraint ◽  
Bowel Motion ◽  
Peritoneal Space

Abstract Background The goal of this study was to assess small bowel motion and explore the feasibility of using peritoneal space (PS) to replace bowel loops (BL) via the dose constraint method to spare the small bowel during intensity-modulated radiotherapy (IMRT) for rectal cancer. Methods A total of 24 patients with rectal cancer who underwent adjuvant radiotherapy were selected. Weekly repeat CT scans from pre-treatment to the fourth week of treatment were acquired and defined as Plan, 1W, 2W, 3W, and 4W. BL and PS contours were delineated in all of the scans. Two IMRT plans called PPS and PBL were designed on Plan CT using two dose PS and BL constraint methods, respectively, and then copied to CT 1 ~ 4W. The shift%, dose volume, and NTCP of the small bowel in PPS and PBL during treatment were evaluated. Results Overall, 109 sets of CT scans from 24 patients were acquired, and 218 plans were designed and copied. The PS and BL volumes were 1339.28 cc and 250.27 cc. The BL and PS shift% V15 was 28.48% and 11.79% (p = 0.000), which was less in the prone position than in the supine position (25.24% vs 32.10%, p = 0.000; 9.9% vs 14.85%, p = 0.000). On all of the CT scans, most PPS small bowel dose volumes were less than from PBL. V15 was 170.07 cc vs 178.58 cc (p = 0.000), and they had a significant correlation. The NTCP of chronic and acute side effects from PPS was significantly less than PBL (2.80% vs 3.00%, p = 0.018; 57.32% vs 58.64%, p = 0.000). Conclusions This study indicated that small bowel motion may lead to uncertainties in its dose volume and NTCP evaluation during IMRT for rectal cancer. The BL movements were significantly greater than PS, and the prone position was significantly less than the supine position. Using PS instead of BL can spare the small bowel. V15 < 830 cc is the dose constraint standard.

scholarly journals Rectal Dose Is the Other Dosimetric Factor in Addition to Small Bowel for Prediction of Acute Diarrhea during Postoperative Whole-Pelvic Intensity-Modulated Radiotherapy in Gynecologic Patients

Cancers ◽  
2021 ◽  
Vol 13 (3) ◽  
pp. 497
Author(s):  
Eng-Yen Huang ◽  
Yu-Ming Wang ◽  
Shih-Chen Chang ◽  
Shu-Yu Liu ◽  
Ming-Chung Chou
Keyword(s):  
Small Bowel ◽  
Acute Diarrhea ◽  
Intensity Modulated Radiotherapy ◽  
Gynecologic Malignancies ◽  
Image Guided Radiotherapy ◽  
Image Guided ◽  
Intensity Modulated ◽  
Rectal Dose ◽  
Different Levels ◽  
Gynecologic Patients

We studied the association of rectal dose with acute diarrhea in patients with gynecologic malignancies undergoing whole-pelvic (WP) intensity-modulated radiotherapy (IMRT). From June 2006 to April 2019, 108 patients with previous hysterectomy who underwent WP IMRT were enrolled in this cohort study. WP irradiation of 39.6–45 Gy/22–25 fractions was initially delivered to the patients. Common Terminology Criteria for Adverse Events (CTCAE) version 3 was used to evaluate acute diarrhea during radiotherapy. Small bowel volume at different levels of isodose curves (Vn%) and mean rectal dose (MRD) were measured for statistical analysis. The multivariate analysis showed that the MRD ≥ 32.75 Gy (p = 0.005) and small bowel volume of 100% prescribed (V100%) ≥ 60 mL (p = 0.008) were independent factors of Grade 2 or higher diarrhea. The cumulative incidence of Grade 2 or higher diarrhea at 39.6 Gy were 70.5%, 42.2%, and 15.0% (p < 0.001) in patients with both high (V100% ≥ 60 mL and MRD ≥ 32.75 Gy), either high, and both low volume-dose factors, respectively. Strict constraints for the rectum/small bowel or image-guided radiotherapy to reduce these doses are suggested.

scholarly journals Dosimetric Comparisons of Three-dimensional Conformal Radiotherapy, Intensity-Modulated Radiotherapy, and Helical Tomotherapy in Whole Abdominopelvic Radiotherapy for Gynecologic Malignancy

2009 ◽  
Vol 8 (5) ◽  
pp. 369-377 ◽  
Author(s):  
Yong Bae Kim ◽  
Joo Ho Kim ◽  
Kyung Keun Jeong ◽  
Jinsil Seong ◽  
Chang Ok Suh ◽  
...  
Keyword(s):  
Spinal Cord ◽  
Helical Tomotherapy ◽  
Gynecologic Cancer ◽  
Three Dimensional ◽  
Intensity Modulated Radiotherapy ◽  
Conformal Radiotherapy ◽  
Target Volume ◽  
Intensity Modulated ◽  
Target Volumes ◽  
Three Dimensional Conformal Radiotherapy

Objectives The goal of this study was to dosimetrically compare 3-dimensional radiotherapy (3DCRT), intensity-modulated radiotherapy (IMRT), and helical tomotherapy (TOMO) plans for whole abdominopelvic radiotherapy (WART) in patients with gynecologic cancer. Methods Ten patients were selected for WART planning. Doses were prescribed to planning target volumes (PTVs) as the followings: 30 Gy to PTV-whole abdominopelvis (PTV-WA), 40 Gy to PTV-para-aortic lymph node (PTV-PALN), 44 Gy to PTV-pelvis, and 50 Gy to gross target volume (GTV) in 20 fractions. Dose to whole liver, both kidneys, and spinal cord were constrained below each tissue tolerance, and bone marrow (BM)-sparing technique was adopted in IMRT and TOMO. Dosimetric parameters and treatment times were compared among plans. Results Calculated doses in TOMO came most closely to the prescribed dose for coverage of PTV-WA, PTV-PALN, PTV-pelvis, and GTV compared to 3DCRT, and IMRT. In normal organs, TOMO had significantly better dosimetric profiles compared to IMRT and 3DCRT. TOMO significantly reduced V20Gy, and mean dose of whole liver, both kidneys, and spinal cord. The use of BM-sparing technique (BMS) did not impair coverage of target volume in IMRT and TOMO. While IMRT showed no differences of irradiated BM dose using BMS, TOMO with BMS reduced half V20Gy of BM compared to TOMO without BMS. Conclusions TOMO showed dosimetric superiority in target coverage, sparing BM, and other normal organs compared to 3DCRT and IMRT. Clinical experiences will be needed for evaluation of feasibility of WART using TOMO in patients with gynecologic cancer.

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