Pasquier D, Lacornerie T, Betrouni N, Vermandel M, Rousseau J, Lartigau E. [Dosimetric evaluation of an automatic segmentation tool of pelvic structures from MRI images for prostate cancer radiotherapy].
Cancer Radiother 2008;
12:323-30. [PMID:
18436465 DOI:
10.1016/j.canrad.2008.03.001]
[Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2007] [Revised: 02/29/2008] [Accepted: 03/05/2008] [Indexed: 11/25/2022]
Abstract
PURPOSE
An automatic segmentation tool of pelvic structures from MRI images for prostate cancer radiotherapy was developed and dosimetric evaluation of differences of delineation (automatic versus human) is presented here.
MATERIALS AND METHODS
CTV, rectum and bladder were defined automatically and by a physician in 20 patients. Treatment plans based on "automatic" volumes were transferred on "manual" volumes and reciprocally. Dosimetric characteristics of PTV (V(95), minimal, maximal and mean doses), rectum (V(50), V(70), maximal and mean doses) and bladder (V(70), maximal and mean doses) were compared.
RESULTS
Automatic delineation of CTV did not significantly influence dosimetric characteristics of "manual" PTV. Rectal V(50) and V(70) were not significantly different; mean rectal dose is slightly superior (43.2 versus 44.4Gy, p=0.02, Student test). Bladder V(70) was significantly superior too (19.3 versus 21.6, p=0.004). Organ-at-risk (OAR) automatic delineation had little influence on their dosimetric characteristics; rectal V(70) was slightly underestimated (20 versus 18.5Gy, p=0.001).
CONCLUSION
CTV and OAR automatic delineation had little influence on dosimetric characteristics. Software developments are ongoing to enable routine use and interobserver evaluation is needed.
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