Morphology-aware deep learning predicts colorectal cancer survival from whole-slide images
Organizations: Department of Pathology, The Ohio State University Wexner Medical Center, Columbus, OH, USA. · Center for Artificial Intelligence Research, Wake Forest University School of Medicine, Winston-Salem, NC, USA.
Abstract
Background: Five-year survival prediction from hematoxylin-and-eosin whole-slide images could support risk stratification, but the task is weakly supervised, and the tissue morphologies carrying prognostic information remain incompletely characterized. Methods: We conducted a retrospective secondary analysis using TCGA-COAD/READ (n=562) for morphology-specific analysis, Alliance/ CALGB 89803 (n=424) for model development, and SurGen (n=218) for external evaluation. We propose MorphContrast, a morphology-aware contrastive multiple-instance learning framework that uses tissue labels as structural supervision for five-year survival prediction. MorphContrast combines gated-attention pooling with three auxiliary objectives: patch-level morphology labels define within-patient contrasts, outcome concordance or discordance defines cross-patient contrasts within matched morphologies, and diversity regularization discourages representational collapse. Morphology-matched patches from patients with discordant outcomes serve as hard negatives, encouraging prognostic discrimination within comparable histologic contexts. Results: Morphology-specific models show weak but distributed prognostic discrimination: adipose tissue achieves an area under the receiver operating characteristic curve (AUC) of 0.622, stroma achieves 0.604, and both perform comparably to tumor epithelium (0.601-0.605). On Alliance/CALGB 89803, the single model achieves an AUC of 0.642, while the post hoc ensemble reaches a pooled out-of-fold AUC of 0.70 and a risk-group hazard ratio of 3.79 (95% confidence interval: 2.55-5.63). On the external SurGen colon cancer cohort (n=218), the single model and ensemble achieve AUCs of 0.669 and 0.678, respectively. Conclusions: These findings support tissue morphology as structural supervision for outcome-aware representation learning in colorectal cancer prognosis.
Figures & tables
| Morphology | AUC | Sen | Spec |
|---|---|---|---|
| Fat (adipose) | |||
| Adenocarcinoma high-grade | |||
| Adenoma high-grade dysp. | |||
| Stroma | |||
| Adenocarcinoma low-grade | |||
| Normal epithelium |
| Model | AUC | Bal-Acc | Sen | Spec |
|---|---|---|---|---|
| MorphContrast | ||||
| MorphContrast (ensemble) |
| Model | AUC | Bal-Acc (%) | Sen (%) | Spec (%) | C-index |
|---|---|---|---|---|---|
| ABMIL Ilse et al. (2018) | |||||
| CLAM Lu et al. (2021) | |||||
| TransMIL Shao et al. (2021) | |||||
| Nakanishi Nakanishi et al. (2023) | |||||
| RRT-MIL Tang et al. (2024) | |||||
| MorphDistill Khan et al. (2026b) |
| Encoder | AUC | Bal-Acc (%) | Sen (%) | Spec (%) |
|---|---|---|---|---|
| CONCH v1.5 Lu et al. (2024) | ||||
| CTransPath Wang et al. (2022) | ||||
| Lunit ViT-S/8 Kang et al. (2023) | ||||
| Phikon v2 Filiot et al. (2024) | ||||
| Virchow2 Zimmermann et al. (2024) | ||||
| Kaiko ViT-B/8 kaiko.ai et al. (2024) |
| Model | Fold AUC | Pooled AUC [95% CI] | C-index |
|---|---|---|---|
| All fourteen variables | |||
| Nodal burden, T category, grade | |||
| MorphContrast | — | ||
| MorphContrast (ensemble) | — |
| Model | AUC | Bal-Acc (%) | Sen. (%) | Spec. (%) |
|---|---|---|---|---|
| TransMIL Shao et al. (2021) | ||||
| FR-MIL Chikontwe et al. (2022) | ||||
| MHIM-MIL Tang et al. (2023) | ||||
| MorphContrast | ||||
| MorphContrast (ensemble) |
| Loss terms | Five-year survival classification | |||||
|---|---|---|---|---|---|---|
| Configuration | AUC | Bal. Acc. (%) | Sens. (%) | Spec. (%) | ||
| Survival only | ✗ | ✗ | ||||
| ✓ | ✗ | |||||
| ✗ | ✓ | |||||
| Full | ✓ | ✓ | ||||
| Alliance cohort characteristics | ||
|---|---|---|
| Characteristic | Category | Value |
| Number of slides | 424 | |
| Number of patients | 424 | |
| Mean age (years) | 60.47 | |
| Mean household income median (USD) | 43,194.59 | |
| Race | White | 391 |
| Parameter | Value(s) | Setting |
| Hyperparameter search space | ||
| Feature-encoder hidden dimension | Searched | |
| Projection dimension | Searched | |
| Attention hidden dimension | Searched | |
| Initial learning rate | Searched | |
| Decision threshold | Searched | |
| Variable | Model coding |
|---|---|
| Age at enrolment | years, continuous |
| Sex | male vs female |
| Histological grade | III (poorly differentiated) vs I–II |
| T category (depth of invasion) | T4 vs T1–T3 |
| Positive lymph nodes | number, continuous |
| Small blood/lymphatic vessel invasion | present vs absent |