  The high cure rate of cancer is inextricably linked to physicians' accuracy
in diagnosis and treatment, therefore a model that can accomplish
high-precision tumor segmentation has become a necessity in many applications
of the medical industry. It can effectively lower the rate of misdiagnosis
while considerably lessening the burden on clinicians. However, fully automated
target organ segmentation is problematic due to the irregular stereo structure
of 3D volume organs. As a basic model for this class of real applications,
U-Net excels. It can learn certain global and local features, but still lacks
the capacity to grasp spatial long-range relationships and contextual
information at multiple scales. This paper proposes a tumor segmentation model
MPU-Net for patient volume CT images, which is inspired by Transformer with a
global attention mechanism. By combining image serialization with the Position
Attention Module, the model attempts to comprehend deeper contextual
dependencies and accomplish precise positioning. Each layer of the decoder is
also equipped with a multi-scale module and a cross-attention mechanism. The
capability of feature extraction and integration at different levels has been
enhanced, and the hybrid loss function developed in this study can better
exploit high-resolution characteristic information. Moreover, the suggested
architecture is tested and evaluated on the Liver Tumor Segmentation Challenge
2017 (LiTS 2017) dataset. Compared with the benchmark model U-Net, MPU-Net
shows excellent segmentation results. The dice, accuracy, precision,
specificity, IOU, and MCC metrics for the best model segmentation results are
92.17%, 99.08%, 91.91%, 99.52%, 85.91%, and 91.74%, respectively. Outstanding
indicators in various aspects illustrate the exceptional performance of this
framework in automatic medical image segmentation.
