Prostate Cancer
Conditions
Keywords
radiotherapy, MRI, segmentation
Brief summary
Following the major technological and scientific advances in external radiotherapy in recent decades, thanks to the use of three-dimensional conformal techniques combined with intensity modulation, image-guided radiotherapy has enabled radiotherapists to increase doses without increasing sequelae and complications, giving rise to the term dose escalation. Following multiple dose-escalation clinical trials showing better biological control of PSA, the results of the latest phase 3 FLAME trial incorporated the notion of intraprostatic boost in relation to the primary prostate lesion, considered to be the preferred site of neoplastic recurrence in prostate cancer. This leads to the first question, which concerns the identification of the dominant lesion and its precise delimitation. This last point is subject to variation between operators. A retrospective cohort from the Finistère region will therefore be used to develop a number of study points relating to : inter-operator contour variability * Factors influencing contour * Impact of contour variability on dosimetry * Automatic segmentation
Detailed description
Following the major technological and scientific advances in external radiotherapy in recent decades, thanks to the use of three-dimensional conformal techniques combined with intensity modulation, image-guided radiotherapy has enabled radiotherapists to increase doses without increasing sequelae and complications, giving rise to the term dose escalation. Following multiple dose-escalation clinical trials showing better biological control of PSA, the results of the latest phase 3 FLAME trial incorporated the notion of intraprostatic boost in relation to the primary prostate lesion, considered to be the preferred site of neoplastic recurrence in prostate cancer. One of the issues raised by such a study is the methodology used to contour the tumour lesion, an issue which concerns the whole field of radiotherapy. The reference imaging technique for diagnosing prostate cancer, and more specifically the dominant tumour lesion, is multiparametric Magnetic Resonance Imaging. This leads to the first question, which concerns the identification of the dominant lesion and its precise delimitation. This last point is subject to variation between operators. A retrospective cohort from the Finistère region will therefore be used to develop a number of study points relating to : inter-operator contour variability * Factors influencing contour * Impact of contour variability on dosimetry * Automatic segmentation
Interventions
None listed
Sponsors
University Hospital, Brest
Study design
Observational model
COHORT
Time perspective
RETROSPECTIVE
Eligibility
Sex/Gender
ALL
Age
18 Years to No maximum
Healthy volunteers
No
Inclusion criteria
* Age ≥ 18 years * Histologically proven localized prostatic neoplasia on trans-rectal biopsies. * Multiparametric prostate MRI performed prior to prostate biopsies. * No opposition expressed * Patient affiliated to a social security scheme
Exclusion criteria
* History of surgery, prostatic irradiation or hormonal treatment prior to diagnosis. * History of prostate cancer * No identifiable target lesion on mpMRI (\<PIRADS 3) * Opposition formulated * Patient under legal protection (guardianship, curatorship, etc.)
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Inter-observer variability | through study completion, an average of 6 months | The main criterion for judging inter-observer variability is the spatial overlap of contours on mpMRI, represented by the DICE similarity coefficient, which ranges from 0 to 1, where 1 represents zero variability between contours of the same lesion. |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Clinical factors influencing inter-observer variability. | through study completion, an average of 6 months | Subgroup analysis of radio-clinical-histological factors likely to influence inter-observer variability. |
| Assessing inter-sequence reproducibility | through study completion, an average of 6 months | Assessing inter-sequence reproducibility |
| Dosimetric impact of Inter-observer variability | through study completion, an average of 6 months | The influence of variability on dosimetry in IMRT/VMAT conformal radiotherapy. |
Other
| Measure | Time frame | Description |
|---|---|---|
| Automatic segmentation of prostatic tumors | through study completion, an average of 6 months | Contour variability using a deep-learning automated segmentation technique, with and without implementation of factors identified as impacting contour in manual technique. |
Countries
France
Contacts
Primary ContactVincent BOURBONNE, MD, PhD
Outcome results
None listed