Unleashing the Power of Prompt-driven Nucleus Instance Segmentation
Zhongyi Shui, Yunlong Zhang, Kai Yao, Chenglu Zhu, Sunyi Zheng, Jingxiong Li, Honglin Li, Yuxuan Sun, Ruizhe Guo, Lin Yang
TL;DR
PromptNucSeg introduces a prompt-driven approach to nucleus instance segmentation in histology images by pairing a nucleus prompter with a fine-tuned Segment Anything Model (SAM). The prompter automatically generates a unique point prompt for each nucleus, aided by an auxiliary nuclear region segmentation task, while adjacent nuclei are used as negative prompts to handle overlaps; a Hungarian matching-based association ensures correct prompt–nucleus pairing. The SAM segmentor is trained with positive prompts per nucleus, enabling one-to-one nucleus mask outputs without heavy post-processing. Across Kumar, CPM-17, and PanNuke, PromptNucSeg achieves state-of-the-art PQ scores and strong nucleus detection/classification with favorable efficiency, though it exhibits higher model size and storage requirements that future work could mitigate through pruning and alternative SAM-like models.
Abstract
Nucleus instance segmentation in histology images is crucial for a broad spectrum of clinical applications. Current dominant algorithms rely on regression of nuclear proxy maps. Distinguishing nucleus instances from the estimated maps requires carefully curated post-processing, which is error-prone and parameter-sensitive. Recently, the Segment Anything Model (SAM) has earned huge attention in medical image segmentation, owing to its impressive generalization ability and promptable property. Nevertheless, its potential on nucleus instance segmentation remains largely underexplored. In this paper, we present a novel prompt-driven framework that consists of a nucleus prompter and SAM for automatic nucleus instance segmentation. Specifically, the prompter learns to generate a unique point prompt for each nucleus while the SAM is fine-tuned to output the corresponding mask for the prompted nucleus. Furthermore, we propose the inclusion of adjacent nuclei as negative prompts to enhance the model's capability to identify overlapping nuclei. Without complicated post-processing, our proposed method sets a new state-of-the-art performance on three challenging benchmarks. Code is available at \url{github.com/windygoo/PromptNucSeg}
