CAMELYON17: Moving the challenge to patient level Oscar Geessink Radboud University Medical Center Nijmegen, The Netherlands

Aim To evaluate algorithms for automated assessment of H&E-stained lymph node slides Detection Lesion-level + Slide-level

Aim To evaluate algorithms for automated assessment of H&E-stained lymph node slides Detection Lesion-level + Slide-level Detection + Classification Patient-level

Motivation for CAMELYON17 In clinical practice: There are multiple lymph node slides per patient It’s irrelevant to detect all lesions in a single slide Pathologist have to report on isolated tumor cells as well

TNM-staging system Tumor – lymph Node – Metastasis Classify the extent of cancer spread Indication of patient prognosis Guide treatment pN-stage is an essential part of TNM Therapeutic implications for breast cancer patients

Task Determine a pN-stage per patient Two categories of lymph node metastasis: Macro: > 2.0 mm Micro: > 0.2 mm ( or > 200 cells), but < 2.0 mm Isolated tumor cells, are not counted as metastases: ITC: < 0.2 mm (or < 200 cells)

Task Simplified pN-stage: pN0: No tumor cells pN0(i+): Only ITCs pN1mi: Only micro-metastases pN1: Metastases in 1–3 nodes, at least 1 macro pN2: Metastases in 4–9 nodes, at least 1 macro

Patients Slides from 5 centers Forged artificial “patients” 1 patient = 5 slides Every patient labeled with a pN-stage 1 slide = 1 lymph node Every slide labeled: Macro Micro ITC Negative

Patients Training_Patient_024 pN-stage: pN1 Slides from 5 centers Slide 1: Micro Slide 2: Macro Slide 3: Micro Slide 4: ITC Slide 5: Negative Slides from 5 centers Forged artificial “patients” 1 patient = 5 slides Every patient labeled with a pN-stage 1 slide = 1 lymph node Every slide labeled: Macro Micro ITC Negative

Training data 400 slides Lesion-level annotations

Training data 400 slides Lesion-level annotations 500 slides (100 patients) Slide-level labels Patient-level labels 50 Lesion-level annotations

Training data Training_Patient_024 pN-stage: pN1 400 slides Slide 1: Micro Slide 2: Macro Slide 3: Micro Slide 4: ITC Slide 5: Negative 400 slides Lesion-level annotations 500 slides (100 patients) Slide-level labels Patient-level labels 50 Lesion-level annotations

Testing data 500 slides (100 patients) No labels/annotations

Testing data Test_Patient_151 pN-stage: ? 500 slides (100 patients) No labels/annotations

Questions?