MUSE: Harnessing Precise and Diverse Semantics for Few-Shot Whole Slide Image Classification
Organizations: School of Big Data & Software Engineering, Chongqing University · School of Computer Science & Technology, Chongqing University
Abstract
In computational pathology, few-shot whole slide image classification is primarily driven by the extreme scarcity of expert-labeled slides. Recent vision-language methods incorporate textual semantics generated by large language models, but treat these descriptions as static class-level priors that are shared across all samples and lack sample-wise refinement. This limits both the diversity and precision of visual-semantic alignment, hindering generalization under limited supervision. To overcome this, we propose the stochastic MUlti-view Semantic Enhancement (MUSE), a framework that first refines semantic precision via sample-wise adaptation and then enhances semantic richness through retrieval-augmented multi-view generation. Specifically, MUSE introduces Sample-wise Fine-grained Semantic Enhancement (SFSE), which yields a fine-grained semantic prior for each sample through MoE-based adaptive visual-semantic interaction. Guided by this prior, Stochastic Multi-view Model Optimization (SMMO) constructs an LLM-generated knowledge base of diverse pathological descriptions per class, then retrieves and stochastically integrates multiple matched textual views during training. These dynamically selected texts serve as enriched semantic supervisions to stochastically optimize the vision-language model, promoting robustness and mitigating overfitting. Experiments on three benchmark WSI datasets show that MUSE consistently outperforms existing vision-language baselines in few-shot settings, demonstrating that effective few-shot pathology learning requires not only richer semantic sources but also their active and sample-aware semantic optimization. Our code is available at: https://github.com/JiahaoXu-god/CVPR2026_MUSE.
Figures & tables
| Dataset | Model | 4-shot | 8-shot | 16-shot | ||||||
|---|---|---|---|---|---|---|---|---|---|---|
| ACC | AUC | F1 Score | ACC | AUC | F1 Score | ACC | AUC | F1 Score | ||
| CAMELYON | Mean Pooling | 59.07 ±3.03 | 51.19 ±4.81 | 47.17 ±5.19 | 64.05 ±4.14 | 61.53 ±5.07 | 55.14 ±2.90 | 65.83 ±1.96 | 62.50 ±4.56 | 55.04 ±7.53 |
| Max Pooling | 62.93 ±4.20 | 62.50 ±8.88 | 55.58 ±7.61 | 70.37 ±5.00 | 74.63 ±4.38 | 67.64 ±4.44 | 74.46 ±6.46 | 78.38 ±8.12 | 72.15 ±6.45 | |
| ABMIL [ 22 ] | 62.04 ±2.77 | 58.98 ±7.37 | 49.61 ±8.85 | 71.52 ±10.41 | 75.05 ±11.03 | 69.69 ±10.15 | 82.37 ±7.10 | 85.48 ±6.22 | 81.04 ±7.36 | |
| DSMIL [ 24 ] | 59.44 ±9.00 | 54.45 ±10.00 | 53.01 ±9.16 | 73.19 ±6.93 | 74.63 ±9.69 | 70.20 ±8.79 | 84.72 ±5.11 | 87.80 ±4.69 | 83.60 ±5.35 | |
| CLAM-SB [ 30 ] | 57.59 ±6.18 | 55.42 ±9.81 | 53.67 ±6.09 | 71.67 ±7.50 | 73.56 ±10.40 | 67.16 ±10.43 | 81.30 ±9.97 | 84.65 ±10.30 | 79.91 ±10.34 | |
| BM | TI | SFSE | SMMO | ACC | AUC | F1 Score | |
|---|---|---|---|---|---|---|---|
| 16-shot | 82.37 | 85.48 | 81.04 | ||||
| 86.61 | 90.13 | 85.41 | |||||
| 86.72 | 90.20 | 85.33 | |||||
| 87.99 | 90.95 | 86.70 | |||||
| 89.70 | 92.52 | 88.59 | |||||
| 8-shot | 71.52 | 75.05 | 69.69 |
| Retrieval Method | ACC | AUC | F1 Score | |
|---|---|---|---|---|
| 16-shot | Random | 88.17 | 90.86 | 87.08 |
| L2-norm | 87.06 | 90.94 | 85.93 | |
| Cosine | 89.70 | 92.52 | 88.59 | |
| 8-shot | Random | 84.20 | 87.66 | 82.70 |
| L2-norm | 84.49 | 88.40 | 83.07 | |
| Cosine | 84.01 | 88.32 | 82.42 |
| Optimization Strategy | ACC | AUC | F1 Score | |
|---|---|---|---|---|
| 16-shot | Multi-mean | 87.36 | 90.23 | 86.23 |
| Stochastic | 89.70 | 92.52 | 88.59 | |
| 8-shot | Multi-mean | 84.08 | 89.14 | 81.70 |
| Stochastic | 84.01 | 88.32 | 82.42 | |
| 4-shot | Multi-mean | 70.33 | 73.53 | 65.01 |
| Stochastic | 74.86 | 76.65 | 68.66 |
| Method | ACC | AUC | F1 Score | |
|---|---|---|---|---|
| 16-shot | Deepseek-R1-Distill-Qwen-7B | 87.65 | 90.93 | 86.47 |
| Llama-3.2-1B | 87.17 | 90.23 | 85.95 | |
| Qwen2-7B | 89.70 | 92.52 | 88.59 | |
| 8-shot | Deepseek-R1-Distill-Qwen-7B | 84.94 | 89.04 | 83.44 |
| Llama-3.2-1B | 84.20 | 87.66 | 82.70 | |
| Qwen2-7B | 84.01 | 88.32 | 82.42 |
| Category | Description | |
|---|---|---|
| CAMELYON | Normal | In high-resolution imaging, a normal lymph node exhibits uniform nuclear staining with homogeneous chromatin that lacks coarse granularity or heterogeneity. The vascular distribution is regular, featuring well-organized capillaries and small vessels without any signs of abnormal dilation or neovascularization. There are no non-physiological speckles, such as pigment deposits, debris, or staining artifacts, and the boundaries between different tissue regions show smooth transitions without abrupt changes or protrusions. |
| Tumor | In high-resolution imaging of a metastatic lymph node, cellular crowding is evident with densely packed cells often forming clusters or sheets, indicative of significant tumor burden. Concurrently, irregular or distorted vascular structures are observed, showing signs of compression, dilation, or irregular branching of blood vessels, suggesting compromised microvascular integrity. Additionally, increased nuclear basophilia is noted, characterized by darker purple nuclei due to elevated DNA content in the tumor cells, reflecting their proliferative activity. Lastly, diffuse infiltration patterns are present, where tumor cells spread along existing tissue frameworks, displacing normal lymphoid architecture and disrupting the orderly arrangement of lymphocytes and other immune cells. | |
| TCGA-NSCLC | LUAD | Lung adenocarcinoma exhibits a complex morphology that can be systematically described through high-resolution imaging. Notably, some cells display vacuolated or mucinous cytoplasmic changes, indicating alterations in cellular metabolism and possibly reflecting the presence of secretory activity. Additionally, the tumor often features fibrovascular cores within its papillary structures, which provide structural support and potentially contribute to the tumor’s invasive capacity. Angiogenesis is another key feature, characterized by the presence of numerous, thin-walled blood vessels in the tumor stroma, which are crucial for tumor growth and survival. Lastly, there is significant heterogeneity in mucin content, with certain regions producing abundant mucin, while others show little or no production, suggesting diverse microenvironments and potential for different clinical behaviors. |
| LUSC | In high-resolution imaging of lung squamous cell carcinoma, key features can be systematically described from four perspectives: Intercellular bridges manifest as visible desmosomal connections between tumor cells, indicating cellular cohesion. Polygonal tumor cells are characterized by well-defined, often angular shapes, reflecting the distinctive morphology of these neoplastic cells. The tumor-stroma interface exhibits heterogeneity, with irregular boundaries that highlight the complex interaction between the malignant cells and their microenvironment. Lastly, local variation in mitotic activity is evident, with hotspots of proliferating cells indicating areas of increased cellular division and potential for aggressive growth. | |
| TCGA-BRCA | IDC | Invasive ductal carcinoma exhibits high cellular density with cells closely packed and minimal intervening stroma, leading to a crowded appearance. Ducts often show lumen formation with cellular debris accumulating within them. Surrounding these areas, peritumoral fibrosis is characterized by thickened fibrotic bands that encircle the invasive tumor regions. Additionally, desmoplastic stroma is evident as dense fibrous tissue frequently surrounds the tumor clusters, contributing to a robust and complex microenvironment. |
| ILC | Invasive lobular carcinoma (ILC) can be characterized through high-resolution imaging from four distinct perspectives: In single-file arrangement, tumor cells often infiltrate in linear chains between collagen fibers, creating a linear or string-of-beads appearance. In diffuse infiltration, tumor cells spread in a more scattered, non-nodular manner, leading to a less organized and more widespread distribution. There is typically minimal fibroblast activation with fewer myofibroblasts compared to invasive ductal carcinoma (IDC), resulting in a less fibrotic stroma. Additionally, a targetoid pattern may be observed where tumor cells wrap around normal ductal structures, creating a concentric or target-like appearance around these structures. |
| FM | ACC | AUC | F1 Score |
|---|---|---|---|
| PLIP [ 20 ] | 72.82 | 73.47 | 67.24 |
| MUSK [ 49 ] | 86.72 | 88.28 | 85.18 |
| Prov-GigaPath [ 50 ] | 87.32 | 89.73 | 84.26 |
| CONCH [ 29 ] | 89.70 | 92.52 | 88.59 |
| number of retrieved texts | ACC | AUC | F1 Score | |
|---|---|---|---|---|
| 16-shot | 10 | 87.88 | 91.33 | 86.75 |
| 20 | 89.70 | 92.52 | 88.59 | |
| 80 | 88.43 | 91.63 | 87.26 | |
| 8-shot | 10 | 83.64 | 86.44 | 80.79 |
| 20 | 84.01 | 88.32 | 82.42 | |
| 80 | 84.49 | 88.40 | 83.07 |
| number of experts | ACC | AUC | F1 Score | |
|---|---|---|---|---|
| 16-shot | 4 | 87.91 | 90.38 | 86.64 |
| 8 | 89.70 | 92.52 | 88.59 | |
| 16 | 87.32 | 90.16 | 86.18 | |
| 8-shot | 4 | 82.88 | 87.49 | 81.52 |
| 8 | 84.01 | 88.32 | 82.42 | |
| 16 | 84.31 | 87.60 | 81.94 |
| Ratio | ACC | AUC | F1 Score | |
|---|---|---|---|---|
| 16-shot | 10% | 88.92 | 91.92 | 87.83 |
| 20% | 89.70 | 92.52 | 88.59 | |
| 50% | 88.51 | 91.66 | 87.40 | |
| 100% | 88.51 | 91.62 | 87.53 | |
| 8-shot | 10% | 85.65 | 88.58 | 83.65 |
| 20% | 84.01 | 88.32 | 82.42 |