Learning Melanocytic Cell Masks from Adjacent Stained Tissue
Mikio Tada, Ursula E. Lang, Iwei Yeh, Elizabeth S. Keiser, Maria L. Wei, Michael J. Keiser
TL;DR
This work tackles the variability in melanoma diagnosis by proposing a pixel-level melanocytic cell segmentation method that learns from paired H&E and adjacent Melan-A IHC tissue sections. A automated pipeline aligns H&E with IHC, uses color deconvolution and dilation to generate ground-truth masks, and trains a UNet with a combined Focal and Tversky loss on 512×512 tiles, achieving a mean IOU of $0.64$ on held-out slides. The approach emphasizes robust ground-truth construction through IHC-cytoplasm intersection and image registration, revealing higher performance in melanoma regions and highlighting the importance of artifact removal. This methodology enables in silico IHC labeling without tissue destaining, with potential generalization to other tissue types and antibodies, thus reducing the burden of gigapixel manual annotation in pathology workflows.
Abstract
Melanoma is one of the most aggressive forms of skin cancer, causing a large proportion of skin cancer deaths. However, melanoma diagnoses by pathologists shows low interrater reliability. As melanoma is a cancer of the melanocyte, there is a clear need to develop a melanocytic cell segmentation tool that is agnostic to pathologist variability and automates pixel-level annotation. Gigapixel-level pathologist labeling, however, is impractical. Herein, we propose a means to train deep neural networks for melanocytic cell segmentation from hematoxylin and eosin (H&E) stained sections and paired immunohistochemistry (IHC) of adjacent tissue sections, achieving a mean IOU of 0.64 despite imperfect ground-truth labels.
