nnU-Net v2
Self-configuring segmentation framework: given a labelled dataset it chooses preprocessing, network topology and training schedule automatically, and it remains the baseline to beat on most medical segmentation challenges, including tumour tasks.
At a glance
What it does
Train a strong 2D/3D U-Net on your own annotated CT/MRI/PET volumes without architecture engineering; used for tumour, organ-at-risk and lymph-node segmentation in radiotherapy and radiomics research.
Tasks, data types and cancers
Architecture
Training data
No fixed training corpus. nnU-Net ships no pretrained weights: it configures itself and trains from scratch on whatever labelled dataset the user supplies. In the original work it was applied without any manual adjustment between datasets to the Medical Segmentation Decathlon (10 tasks) and to further biomedical segmentation challenges.
Linked datasets
- benchmark BraTS — Brain Tumor Segmentation Challenge Free registration — standard glioma segmentation benchmark where nnU-Net variants placed first repeatedly
Evaluation
| Benchmark / dataset | Metric | Value | External validation | Source |
|---|---|---|---|---|
| Medical Segmentation Decathlon + 23 public challenges (paper) | Dice | first place or top tier on the majority | yes | Source |
How to run
pip install nnunetv2
nnUNetv2_plan_and_preprocess -d 001 --verify_dataset_integrity
nnUNetv2_train 001 3d_fullres 0
nnUNetv2_predict -i imagesTs/ -o preds/ -d 001 -c 3d_fullres
Regulatory status and intended use
Regulatory status is quoted from the source linked above and can change. Research-use-only models must not be used for clinical decisions.
Limitations and bias
- Needs voxel-level labels; no pretraining shortcut.
- Long training times; the cascade variant is heavy.
Sources
This page is educational — it is not medical advice and does not replace consultation with an oncologist. Diagnostic and treatment decisions are made solely by specialist physicians.