Cancer3.AIAI in OncologyAI Models › CONCH
Foundation model Gated weights (licence click-through) Research use only pathology

CONCH CONCH (v1)

Vision-language foundation model for pathology: an image encoder and a text encoder trained together on 1.17 million histopathology image–caption pairs, enabling zero-shot classification and image–text retrieval without labelled slides.

58 735 downloads / month ♥ 204 updated 2024-05-05 gated

At a glance

DeveloperMahmood Lab, Brigham and Women's Hospital / Harvard Medical School
VersionCONCH (v1)
Released2024-03-19
Licencecc-by-nc-nd-4.0
AvailabilityGated weights (licence click-through)
KindFoundation model
Regulatory statusResearch use only
Parameters~395M total (image tower ~86M)

What it does

CONCH maps tiles and free-text descriptions into one embedding space. You can classify a tile by comparing it with text prompts ('invasive ductal carcinoma' vs 'lobular carcinoma'), retrieve images for a sentence, or use the image tower as a strong feature extractor.

Notable uses in oncology

Evaluated on 14 benchmarks spanning subtyping, grading, retrieval and segmentation prompts; the text side lets small labs prototype classifiers from prompts before any annotation.

Tasks, data types and cancers

CancerPan-cancer
Input448×448 tile (image tower) / free text up to the tokenizer limit
Output512-dimensional joint embedding; text logits

Architecture

FamilyCoCa-style contrastive + captioning vision-language model
BackboneViT-B/16 image encoder + transformer text encoder/decoder
Parameters~395M total (image tower ~86M)
Pre-trainingcontrastive alignment + captioning on image–caption pairs, after image-only pretraining

Pairs came from the PubMed Central open-access subset and in-house educational material; captions were cleaned and split into pathology-relevant segments before training.

Training data

1.17 million image–caption pairs after filtering (figures from open-access biomedical literature plus institutional educational content), preceded by image-only self-supervised pretraining on institutional slides.

Training set size1.17M image–caption pairs
InstitutionsBWH / MGH; PubMed Central OA figures
Populations / geographyliterature-derived — global but publication-biased

Linked datasets

Evaluation

Benchmark / datasetMetricValueExternal validationSource
zero-shot subtyping (TCGA-derived tasks) balanced accuracy best among compared vision-language models yes Source
image–text retrieval (in-house and public sets) Recall@K reported in paper yes Source

How to run

# generic timm loader — check the model card for the exact init args and image normalisation
import timm, torch
from huggingface_hub import login
login()  # gated repos: accept the licence on huggingface.co first
model = timm.create_model('hf-hub:MahmoodLab/CONCH', pretrained=True)
model.eval()
cfg = timm.data.resolve_data_config({}, model=model)
transform = timm.data.create_transform(**cfg)
# emb = model(transform(tile).unsqueeze(0))  # 1 x D tile embedding
Librarycustom (conch package, PyTorch)
Hardwaresingle GPU for inference

Install from the GitHub repo; weights are gated on Hugging Face. Zero-shot prompts should follow the phrasing templates in the repo — prompt wording moves accuracy by several points.

Regulatory status and intended use

Regulatory statusResearch use only
Intended useResearch use; not a device.

Source →

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

  • Caption data is literature-biased: rare entities and non-English terminology are under-represented.
  • Zero-shot accuracy is prompt-sensitive; report the prompts you used.
  • Non-commercial licence.

Sources

  1. Lu MY et al. A visual-language foundation model for computational pathology. Nat Med 2024
  2. Hugging Face — MahmoodLab/CONCH

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.