PO.BCS02.05 · 生物信息与计算
基于AI分诊三维病理的数据高效形态学深度学习用于细粒度Gleason分级
Data-efficient morphological deep learning for fine-grained Gleason grading based on AI-triaged 3D pathology
作者与单位 Authors & Affiliations
摘要 Abstract
中文摘要
前列腺癌风险评估依赖于二维组织学,其仅对一小部分组织进行取样且缺乏三维结构背景,常导致模糊不清。采用开顶式光片显微镜的无玻片三维病理提供了完整活检的体积视图,在无需破坏性切片的情况下提供更丰富的形态学信息。然而,三维数据集的庞大规模使得人工审阅不切实际。先前的研究表明,AI分诊模型能够在三维病理数据集中识别出高风险的二维切片,供病理医师进行省时的审阅,但这些模型是在有限的标记数据集上训练的,因此容易过拟合,尤其是对于细粒度的多分类任务(例如Gleason分级)。为解决这一问题,我们研究了数据高效、分割引导的原型学习能否更好地捕捉形态学模式以改善Gleason分级。为在有限监督下实现细粒度Gleason分级,我们开发了SCOPE,一种用于三维病理的分割引导跨切片原型学习(Segmentation-guided CrOss-slice PrototypE learning)框架。原型学习通过将大量图块特征映射到紧凑的原型特征(每个原型代表一种独特的组织形态)来帮助缓解过拟合。为将这一范式适配到三维病理,我们首先在未标记的三维体积上进行预训练,以初始化捕捉队列广泛形态学多样性的原型。然后,我们使用三维分割掩膜作为结构先验来引导原型细化。除原型学习外,我们采用2.5D多示例学习(MIL)策略,纳入相邻切片的背景信息,以提高每个目标切片的特征质量。来自每个切片的聚合原型特征用于训练分级分类器。为评估我们的方法,我们将SCOPE应用于59例前列腺癌患者的队列,其切片级注释(Gleason分级)由三位病理医师共识确立。使用留一交叉验证方案,我们的框架在细粒度Gleason分级任务(即GG1、GG2、GG3或GG > 3)上实现了0.819的AUC。相比之下,基线原型学习模型实现的AUC为0.699。我们进一步量化了SCOPE中每个组件的贡献,发现分割引导的特征贡献最大,其次是2.5D MIL方案和基于聚类的预训练。总之,SCOPE证实数据高效、分割引导的原型学习能够捕捉细粒度的三维形态学模式,从而改善前列腺癌Gleason分级。通过将基于聚类的预训练与分割衍生的结构先验以及2.5D MIL方案相结合,SCOPE在标记数据有限时为三维病理提供了一种高性能、可解释且具临床可操作性的AI分诊工具。
查看英文原文 English abstract
Prostate cancer risk assessment relies on 2D histology, which samples only a small portion of tissue and lacks 3D architectural context, often leading to ambiguities. Slide-free 3D pathology using open-top light-sheet microscopy provides volumetric views of intact biopsies, offering richer morphological information without destructive sectioning. Yet the massive scale of 3D datasets makes manual review impractical. Prior work has shown that AI-triage models can identify high-risk 2D sections within 3D pathology datasets for time-efficient pathologist review, but these models are trained on limited labeled datasets, and thus prone to overfitting, especially for fine-grained multiclass tasks (e.g., Gleason grading). To address this, we investigate whether data-efficient, segmentation-guided prototype learning can better capture morphological patterns for improved Gleason grading. To enable fine-grained Gleason grading under limited supervision, we developed SCOPE, a Segmentation-guided CrOss-slice PrototypE learning framework for 3D pathology. Prototype learning helps mitigate overfitting by mapping large numbers of patch features into compact prototype features, each of which represents a distinct tissue morphology. To adapt this paradigm to 3D pathology, we first pretrain on unlabeled 3D volumes to initialize prototypes that capture the broad morphological diversity of the cohort. We then use 3D segmentation masks as structural priors to guide prototype refinement. In addition to the prototype learning, we adopt a 2.5D multiple-instance learning (MIL) strategy that incorporates context from neighboring slices to improve the feature quality for each slice of interest. Aggregated prototype features from each slice are used to train classifiers for grading. To evaluate our approach, we applied SCOPE to a cohort of 59 prostate cancer patients with slice-level annotations (Gleason grades) established by consensus among three pathologists. Using a leave-one-out cross-validation protocol, our framework achieved an AUC of 0.819 for the fine-grained Gleason grading task (i.e., GG1, GG2, GG3, or GG > 3). In comparison, the baseline prototype learning model achieved an AUC of 0.699. We further quantified the contribution of each component in SCOPE, finding that segmentation-guided features contribute the most, followed by the 2.5D MIL formulation and clustering-based pretraining. In summary, SCOPE confirms that data-efficient, segmentation-guided prototype learning can capture fine-grained 3D morphological patterns that improve prostate cancer Gleason grading. By integrating clustering-based pretraining with segmentation-derived structural priors and a 2.5D MIL formulation, SCOPE delivers a high-performance, interpretable, and clinically actionable AI-triage tool for 3D pathology when labeled data is limited.
利益披露 Disclosure
R. Yan, None..
G. Gao, None..
A. Song, None..
H. Hsieh, None..
Y. Zhao, None..
C. Almagro-Pérez, None.
L. D. True,
Alpenglow Biosciences Other Business Ownership, a co-founder and holder of equity in Alpenglow Biosciences, Inc..
F. Mahmood, None..
P. Lal, None..
A. Madabhushi, None.
J. T. Liu,
Alpenglow Biosciences Other Business Ownership, a co-founder and board member of Alpenglow Biosciences, Inc.