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Inter-observer Variability in the Segmentation of Prostate Tumour Lesions Using Multiparametric MRI (VARIOP)

Recruiting
Conditions
Prostate Cancer
Registration Number
NCT05996289
Lead Sponsor
University Hospital, Brest
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

Recruitment & Eligibility

Status
RECRUITING
Sex
All
Target Recruitment
70
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.)

Study & Design

Study Type
OBSERVATIONAL
Study Design
Not specified
Primary Outcome Measures
NameTimeMethod
Inter-observer variabilitythrough 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 Outcome Measures
NameTimeMethod
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 reproducibilitythrough study completion, an average of 6 months

Assessing inter-sequence reproducibility

Dosimetric impact of Inter-observer variabilitythrough study completion, an average of 6 months

The influence of variability on dosimetry in IMRT/VMAT conformal radiotherapy.

Trial Locations

Locations (1)

Chu Brest

🇫🇷

Brest, France

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