Limits...
Effects of bladder distension on dose distribution of vaginal vault brachytherapy in patients with endometrial cancer.

Guler OC, Onal C, Acibuci I - J Contemp Brachytherapy (2014)

Bottom Line: Mean minimum dose to most exposed 2 cc (D2cc) volume also rose significantly at bladder (5.40 Gy vs. 4.55 Gy [18.7%]; p < 0.001), as opposed to near-significant reductions in D2cc at sigmoid colon (15.1%; p = 0.11) and at small bowel (10.5%; p = 0.14).A full bladder had no effect on dose to 50% volume (D50%) of bladder or rectum, and declines seen in mean D50% values of sigmoid colon (22.7%; p = 0.12) and small bowel (19.0%; p = 0.13) again fell short of statistical significance.The combination of a full bladder and an empty rectum may cause significant unwanted increases in BRT dosing of bladder, without significantly impacting sigmoid colon and small bowel exposures.

View Article: PubMed Central - PubMed

Affiliation: Department of Radiation Oncology, Baskent University Faculty of Medicine, Adana, Turkey.

ABSTRACT

Purpose: To investigate dosimetric effects of bladder distention on organs at risk (OARs) during treatment of endometrial cancer using 3D image-based planning of postoperative vaginal vault brachytherapy (BRT).

Material and methods: Fifteen patients with early-stage endometrial cancer were studied, each undergoing adjuvant BRT of vaginal vault via 3.5 cm diameter cylinder. As treatment, 25 Gy in 5 fractions were delivered to 5 mm depth of the vaginal mucosa. Dose-volume histograms of OARs were generated individually with bladder empty and with bladder inflated by sterile saline (180 ml), to compare doses received.

Results: Bladder distention appreciably impacted dosimetry of bladder, sigmoid colon, and small bowel, but dosimetry of rectum was unaffected. With bladder inflated, mean cylinder-to-bowel distance increased significantly (1.69 cm vs. 1.20 cm; p = 0.006). Mean minimum dose to most exposed 2 cc (D2cc) volume also rose significantly at bladder (5.40 Gy vs. 4.55 Gy [18.7%]; p < 0.001), as opposed to near-significant reductions in D2cc at sigmoid colon (15.1%; p = 0.11) and at small bowel (10.5%; p = 0.14). A full bladder had no effect on dose to 50% volume (D50%) of bladder or rectum, and declines seen in mean D50% values of sigmoid colon (22.7%; p = 0.12) and small bowel (19.0%; p = 0.13) again fell short of statistical significance.

Conclusions: The combination of a full bladder and an empty rectum may cause significant unwanted increases in BRT dosing of bladder, without significantly impacting sigmoid colon and small bowel exposures. These findings should be validated through further clinical studies.

No MeSH data available.


Related in: MedlinePlus

Organs at risk (OARs) in axial plane with bladder empty (A) and full (B) (small bowel displaced by vaginal cylinder applicator); Vaginal cylinder (relative to OARs) in sagittal plane with bladder empty (C) and full (D) (small bowel displaced anteriorly and superiorly but stable posteriorly)
© Copyright Policy - open-access
Related In: Results  -  Collection

License
getmorefigures.php?uid=PMC4300363&req=5

Figure 0001: Organs at risk (OARs) in axial plane with bladder empty (A) and full (B) (small bowel displaced by vaginal cylinder applicator); Vaginal cylinder (relative to OARs) in sagittal plane with bladder empty (C) and full (D) (small bowel displaced anteriorly and superiorly but stable posteriorly)

Mentions: Median age of the 15 patients analyzed was 58 years (range, 38-81 years). Eight patients (53%) had stage IA endometrial cancer, and seven patients (47%) had stage IB disease. As demonstrated in Table 1, all target and OAR volumes (except bladder) were similar. Typically, small bowel was displaced anteriorly and superiorly from the vaginal cylinder applicator (shown in Fig. 1), significantly increasing mean cylinder-to bowel distance (1.69 cm vs. 1.20 cm; p = 0.006).


Effects of bladder distension on dose distribution of vaginal vault brachytherapy in patients with endometrial cancer.

Guler OC, Onal C, Acibuci I - J Contemp Brachytherapy (2014)

Organs at risk (OARs) in axial plane with bladder empty (A) and full (B) (small bowel displaced by vaginal cylinder applicator); Vaginal cylinder (relative to OARs) in sagittal plane with bladder empty (C) and full (D) (small bowel displaced anteriorly and superiorly but stable posteriorly)
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4300363&req=5

Figure 0001: Organs at risk (OARs) in axial plane with bladder empty (A) and full (B) (small bowel displaced by vaginal cylinder applicator); Vaginal cylinder (relative to OARs) in sagittal plane with bladder empty (C) and full (D) (small bowel displaced anteriorly and superiorly but stable posteriorly)
Mentions: Median age of the 15 patients analyzed was 58 years (range, 38-81 years). Eight patients (53%) had stage IA endometrial cancer, and seven patients (47%) had stage IB disease. As demonstrated in Table 1, all target and OAR volumes (except bladder) were similar. Typically, small bowel was displaced anteriorly and superiorly from the vaginal cylinder applicator (shown in Fig. 1), significantly increasing mean cylinder-to bowel distance (1.69 cm vs. 1.20 cm; p = 0.006).

Bottom Line: Mean minimum dose to most exposed 2 cc (D2cc) volume also rose significantly at bladder (5.40 Gy vs. 4.55 Gy [18.7%]; p < 0.001), as opposed to near-significant reductions in D2cc at sigmoid colon (15.1%; p = 0.11) and at small bowel (10.5%; p = 0.14).A full bladder had no effect on dose to 50% volume (D50%) of bladder or rectum, and declines seen in mean D50% values of sigmoid colon (22.7%; p = 0.12) and small bowel (19.0%; p = 0.13) again fell short of statistical significance.The combination of a full bladder and an empty rectum may cause significant unwanted increases in BRT dosing of bladder, without significantly impacting sigmoid colon and small bowel exposures.

View Article: PubMed Central - PubMed

Affiliation: Department of Radiation Oncology, Baskent University Faculty of Medicine, Adana, Turkey.

ABSTRACT

Purpose: To investigate dosimetric effects of bladder distention on organs at risk (OARs) during treatment of endometrial cancer using 3D image-based planning of postoperative vaginal vault brachytherapy (BRT).

Material and methods: Fifteen patients with early-stage endometrial cancer were studied, each undergoing adjuvant BRT of vaginal vault via 3.5 cm diameter cylinder. As treatment, 25 Gy in 5 fractions were delivered to 5 mm depth of the vaginal mucosa. Dose-volume histograms of OARs were generated individually with bladder empty and with bladder inflated by sterile saline (180 ml), to compare doses received.

Results: Bladder distention appreciably impacted dosimetry of bladder, sigmoid colon, and small bowel, but dosimetry of rectum was unaffected. With bladder inflated, mean cylinder-to-bowel distance increased significantly (1.69 cm vs. 1.20 cm; p = 0.006). Mean minimum dose to most exposed 2 cc (D2cc) volume also rose significantly at bladder (5.40 Gy vs. 4.55 Gy [18.7%]; p < 0.001), as opposed to near-significant reductions in D2cc at sigmoid colon (15.1%; p = 0.11) and at small bowel (10.5%; p = 0.14). A full bladder had no effect on dose to 50% volume (D50%) of bladder or rectum, and declines seen in mean D50% values of sigmoid colon (22.7%; p = 0.12) and small bowel (19.0%; p = 0.13) again fell short of statistical significance.

Conclusions: The combination of a full bladder and an empty rectum may cause significant unwanted increases in BRT dosing of bladder, without significantly impacting sigmoid colon and small bowel exposures. These findings should be validated through further clinical studies.

No MeSH data available.


Related in: MedlinePlus