Hello,
I noticed a discrepancy between the number of provided files and the dataset size stated in the BraTS 2026 Cluster of Challenges: Structured description of the challenge design document for Task 5.
The currently provided dataset contains 1,631,432 jpg-files, all with the prefix train_. However, this does not seem to match the number of cases/patches reported for Task 5 in the document - it reports a lower number of training patches for Task 5 (train: 794,269; val: 298,532).
Could you please clarify whether the provided files represent the complete training set for Task 5, and whether validation/test splits are expected to be released separately?
Thank you!
Created by Ellena Spieß ellena.spiess Thank you @jaydenyou Hi @ujjwalbaid
Just to confim the "NOTA" only means not falling to the 9 regions of interest but they are not necessary clinically healthy. In fact we added some non-GBM cancerous types to create patches. Hope that's clear and we will update the description. Hi @ellena.spiess
I just uploaded the validation data and the unsupervised training data. Hopefully, they will be online soon. Should be within days.
Hi @ujjwalbaid
NOTA is collected from non-GBM cases. Hi @jaydenyou
Thank you for the information. Could you please clarify whether the patches labeled as "None of the Above (NOTA)" are derived from cancerous regions or non-cancerous regions? Hi @jaydenyou
Thank you for your answer & the information. I just wanted to kindly follow up on the validation set you mentioned last week. I checked the folder but couldn’t find them yet, so I wanted to ask whether there is already an estimate of when they might be uploaded.
Thanks a lot in advance!
Hi,
Thank you for pointing out the discrepancy. This year, we made changes to the dataset, so the numbers in the description (train: 794,269; val: 298,532) are no longer correct. The labeled training data now contains 1631432 patches. Sorry for the delay, but we are finalizing the validation set and the unlabeled training images that are likely to be released later this week. As for the test set, we will not release it.
Cheers,
Jayden Hi @vchung and @ellena.spiess,
Thank you both for the information! I can now get access to it. Hi @lzhao,
For the best experience, we encourage you to interact with the challenge through Synapse's new Challenge Portal! This interface is designed to provide a more intuitive way to manage your files and submissions in one place.
For example, all data files for Task 5 are available here:
https://challenges.synapse.org/Challenges/DetailsPage/Task5?id=syn74274097#Data%20Files Hi @lzhao - If you have logged in as a Synopse user, requested access to the dataset, received a confirmation email, and clicked “Join” in that email, you should see a new tab called “Files” in the MICCAI BraTS 2026 Challenge on Synopse. That's where you'll find the data to download. Important: the data is not located in the ‘Dataset’ tab, but under “Files.” Hi,
May I know where the training dataset for task 5 can be accessed? Thanks!
The datasets on the BraTS 2026 Challenge Synapse project seems empty now.