MC-Unet: Multi-scale Convolution Unet for Bladder Cancer Cell Segmentation in Phase-Contrast Microscopy Images

Owing to the high density, low contrast, deformable cell shapes, low inter-cellular shape and appearance variation, and occlusion of the cells by division or fusion especially in phase-contrast microscopy images, it is still a challenging task to segment cells from the complex background. In this work, we proposed a multi-scale convolution Unet (MC-Unet) for bladder cancer cell segmentation in Phase-Contrast microscopy images. More specifically, the second 3x3 convolution of each layer in the standard Unet is replaced with a multi-scale convolution (MC) block with different kernel sizes, such as 1x1, 3x3, and 5x5. To verify the effectiveness of the proposed method, a series of experiments are conducted on the bladder cancer T24 dataset and the MoNuSeg dataset, and the results shows the proposed MC-Unet can obtain better comprehensive performance than the standard Unet.