T6: Detecting Clinically Significant Cancer in Prostate MRI Exams


Objective:
Detect clinically significant prostate cancer (csPCa) lesions using 3D prostate MRI scans. Clinically significant prostate cancer is defined as lesions with an ISUP score ≥ 2.

Patient Population:

  • Patients suspected of having clinically significant prostate cancer (e.g., elevated PSA or abnormal DRE findings).
  • No prior prostate-specific treatments.
  • No previous diagnosis of ISUP ≥ 2 cancer.

Imaging Data:

  • Axial T2-weighted (T2W) MRI
  • Axial high b-value diffusion-weighted imaging (DWI, b ≥ 1000 s/mm²)
  • Axial apparent diffusion coefficient (ADC) maps

Test Data:

  • 1000 cases, from three Dutch centers and one Norwegian center.
  • Scans acquired using Siemens or Philips MRI scanners.

Reference Standard:

  • Positive cases: Confirmed histopathological evidence (ISUP ≥ 2).
  • Negative cases: ISUP ≤ 1 or MRI PI-RADS ≤ 2, supported by ≥ 3 years of clinical follow-up.
  • Voxel-level annotations created using ITK-SNAP v3.80 by trained investigators or a radiology resident, supervised by expert radiologists.
  • All annotations underwent rigorous quality control at the coordinating center (RUMC).

Evaluation Metrics:
Performance is assessed using the unweighted average of:

  • Area Under the Receiver Operator Characteristic Curve (AUROC)
  • Area Under the Precision-Recall Curve (AP)

Relation to Existing Challenges:

  • Task 6 is adapted from the PI-CAI challenge.
  • Validation and test datasets mirror those used in PI-CAI but omit clinical parameters and coronal/sagittal T2 images.
  • PI-CAI aimed to train task-specific models ("narrow AI") on large, partially labeled datasets, whereas UNICORN emphasizes adaptation through few-shot learning on the challenge platform.

Additional Resources: