U-Net based deep learning framework for automated lung nodule segmentation using CT images
Main Article Content
Abstract
Lung cancer is a leading cause of cancer-related fatalities globally. Early detection of lung nodules via CT scans is crucial for prompt diagnosis and treatment. This study presents a U-Net-based deep learning framework for automated lung nodule segmentation with the LIDC-IDRI dataset. The CT images and corresponding segmentation masks were preprocessed and used to train the proposed model. U-Net was adopted to identify the spatial features of lung nodules and to produce the masks at pixel level. The experimental results demonstrated learning performance with an accuracy of 99.44% and 99.46% during training and validation phases, respectively. The model yielded Dice Similarity Coefficient of 0.429 and localized the majority of nodule regions in CT images. Further visual comparison of the masks verified the validity of the proposed method. Thus, it can be concluded that the proposed system can aid in automatic localization of the lung nodules and in developing computer aided diagnosis systems.
Downloads
Article Details
Section

This work is licensed under a Creative Commons Attribution 4.0 International License.
This work is licensed under a Creative Commons Attribution 4.0 International (CC BY 4.0) License. Authors retain the copyright of their work and grant the Journal of Global Research in Multidisciplinary Studies (JGRMS) the right of first publication. This license permits unrestricted use, distribution, adaptation, and reproduction in any medium or format, provided the original author(s), source, and publication are properly credited. Users may copy, redistribute, remix, transform, and build upon the published material for any purpose, including commercial use, in accordance with the terms of the CC BY 4.0 License.
How to Cite
References
[1] C. Gao et al., “Deep learning in pulmonary nodule detection and segmentation: a systematic review,” Eur. Radiol., vol. 35, no. 1, pp. 255–266, Jul. 2024, doi: 10.1007/s00330-024-10907-0.
[2] H. M. Cheo, C. Y. G. Ong, and Y. Ting, “A Systematic Review of AI Performance in Lung Cancer Detection on CT Thorax,” Healthcare, vol. 13, no. 13, p. 1510, Jun. 2025, doi: 10.3390/healthcare13131510.
[3] V. Chaturvedi, “Disease Diagnostic Systems based on AI-Applications in Healthcare: Models, Challenges, and Future Directions,” Int. J. Emerg. Res. Eng. Technol., vol. 6, no. 4, pp. 207–217, Dec. 2025, doi: 10.63282/3050-922X.IJERET-V6I4P125.
[4] S. Mukherjee, “Performance Evaluation of Deep Learning Models for Early Detection of Infectious Diseases in Healthcare Systems,” in SoutheastCon 2026, IEEE, Feb. 2026, pp. 1–6. doi: 10.1109/SoutheastCon63549.2026.11475977.
[5] L. J. Crasta, R. Neema, and A. R. Pais, “A novel Deep Learning architecture for lung cancer detection and diagnosis from Computed Tomography image analysis,” Healthc. Anal., vol. 5, p. 100316, Jun. 2024, doi: 10.1016/j.health.2024.100316.
[6] B. S. Sambit Ranjan Pattanayak, Janmejaya Mishra, VNLN Murthy, Abhilash Pati, Amrutanshu Panigrahi, “Harnessing Grey Wolf Optimization for Early Thyroid Cancer Prediction,” in 2025 International Conference on Responsible, Generative and Explainable AI (ResGenXAI), Bhubaneswar, India: IEEE, 2025, pp. 10–12, September. doi: 10.1109/ResgenXAI64788.2025.11344005.
[7] R. V. S. S. B. R, S. S. Harakannanavar, Z. A. Alsalami, M. S, and G. Vijayakumari, “Early Detection of Sepsis by using Attention based Recurrent Neural Networks with Shapley Additive Exp lanations,” in 2024 International Conference on Integrated Intelligence and Communication Systems (ICIICS), IEEE, Nov. 2024, pp. 1–5. doi: 10.1109/ICIICS63763.2024.10860199.
[8] L. Salhi, K. Moussa, and R. Ben Salah, “Enhanced Pulmonary Nodule Detection and Classification Using Artificial Intelligence on LIDC-IDRI Data,” Explor. Res. Hypothesis Med., vol. 11, no. 1, p. e00032, Jan. 2026, doi: 10.14218/ERHM.2025.00032.
[9] X. Yang et al., “Segmentation and Classification of Lung Cancer Images Using Deep Learning,” Appl. Sci., vol. 16, no. 2, p. 628, Jan. 2026, doi: 10.3390/app16020628.
[10] M. Abumohsen, E. Costa-Montenegro, S. García-Méndez, A. Y. Owda, and M. Owda, “Machine Learning and Deep Learning in Lung Cancer Diagnostics: A Systematic Review of Technical Breakthroughs, Clinical Barriers, and Ethical Imperatives,” AI, vol. 7, no. 1, p. 23, Jan. 2026, doi: 10.3390/ai7010023.
[11] S. K. Chandrappa, S. Paheding, A. A. Reyes-Angulo, and A. Essa, “Attention-Based Spectral Profile Representation for Hyperspectral Image Classification,” in NAECON 2025 - IEEE National Aerospace and Electronics Conference, Dayton, OH, USA: IEEE, 2025, pp. 1–6, November. doi: 10.1109/NAECON65708.2025.11235401.
[12] M. K. Faizi et al., “Deep learning-based lung cancer classification of CT images,” BMC Cancer, vol. 25, no. 1, p. 1056, Jul. 2025, doi: 10.1186/s12885-025-14320-8.
[13] M. Hammad, M. ElAffendi, A. A. A. El-Latif, A. A. Ateya, G. Ali, and P. Plawiak, “Explainable AI for lung cancer detection via a custom CNN on CT images,” Sci. Rep., vol. 15, no. 1, p. 12707, Apr. 2025, doi: 10.1038/s41598-025-97645-5.
[14] B. Jeganathan, “Exploring the Power of Generative Adversarial Networks (GANs) for Image Generation: A Case Study on the MNIST Dataset,” Int. J. Adv. Eng. Manag., vol. 7, no. 1, pp. 21–46, Jan. 2025, doi: 10.35629/5252-07012146.
[15] T. Hu, Y. Lan, Y. Zhang, J. Xu, S. Li, and C.-C. Hung, “A lung nodule segmentation model based on the transformer with multiple thresholds and coordinate attention,” Sci. Rep., vol. 14, no. 1, p. 31743, Dec. 2024, doi: 10.1038/s41598-024-82877-8.
[16] L. Zhi, W. Jiang, S. Zhang, and T. Zhou, “Deep neural network pulmonary nodule segmentation methods for CT images: Literature review and experimental comparisons,” Comput. Biol. Med., vol. 164, p. 107321, Sep. 2023, doi: 10.1016/j.compbiomed.2023.107321.
[17] J. Wu and T. Qian, “A survey of pulmonary nodule detection, segmentation and classification in computed tomography with deep learning techniques,” J. Med. Artif. Intell., vol. 2, pp. 8–8, Apr. 2019, doi: 10.21037/jmai.2019.04.01.
[18] G. K. Subramanyam, K. Srinivas, V. V. R. Indugu, D. S. Gondi, and S. K. G. Subbammagari, “Segmentation-Guided Hybrid Deep Learning for Pulmonary Nodule Detection and Risk Prediction from Multi-Cohort CT Images,” Diseases, vol. 14, no. 1, p. 21, Jan. 2026, doi: 10.3390/diseases14010021.
[19] B. Sahu et al., “Harnessing TLBO-Enhanced Cheetah Optimizer for Optimal Feature Selection in Cancer Data,” Comput. Model. Eng. Sci., pp. 1–26, 2025, doi: 10.32604/cmes.2025.069618.
[20] A. G. Akintola et al., “Integrated deep learning paradigm for comprehensive lung cancer segmentation and classification using mask R-CNN and CNN models,” Franklin Open, vol. 11, p. 100278, Jun. 2025, doi: 10.1016/j.fraope.2025.100278.
[21] R. F. Khan, B.-D. Lee, and M. S. Lee, “Transformers in medical image segmentation: a narrative review,” Quant. Imaging Med. Surg., vol. 13, no. 12, pp. 8747–8767, Dec. 2023, doi: 10.21037/qims-23-542.
[22] H. Jin, C. Yu, J. Zhang, R. Zheng, Y. Fu, and Y. Zhao, “Multitask Swin Transformer for classification and characterization of pulmonary nodules in CT images,” Quant. Imaging Med. Surg., vol. 15, no. 3, pp. 1845–1861, Mar. 2025, doi: 10.21037/qims-24-1619.
[23] L. Lei and W. Li, “Transformer-based multi-task model for lung tumor segmentation and classification in CT images,” J. Radiat. Res. Appl. Sci., vol. 18, no. 3, p. 101657, Sep. 2025, doi: 10.1016/j.jrras.2025.101657.
[24] R. Azad et al., “Advances in medical image analysis with vision Transformers: A comprehensive review,” Med. Image Anal., vol. 91, p. 103000, Jan. 2024, doi: 10.1016/j.media.2023.103000.
[25] K. He et al., “Transformers in medical image analysis,” Intell. Med., vol. 3, no. 1, pp. 59–78, Feb. 2023, doi: 10.1016/j.imed.2022.07.002.
[26] B. Lambert, F. Forbes, S. Doyle, H. Dehaene, and M. Dojat, “Trustworthy clinical AI solutions: A unified review of uncertainty quantification in Deep Learning models for medical image analysis,” Artif. Intell. Med., vol. 150, p. 102830, Apr. 2024, doi: 10.1016/j.artmed.2024.102830.
[27] M. Firmino, A. H. Morais, R. M. Mendoça, M. R. Dantas, H. R. Hekis, and R. Valentim, “Computer-aided detection system for lung cancer in computed tomography scans: Review and future prospects,” Biomed. Eng. Online, vol. 13, no. 1, p. 41, 2014, doi: 10.1186/1475-925X-13-41.
[28] X. Wang, K. Mao, L. Wang, P. Yang, D. Lu, and P. He, “An Appraisal of Lung Nodules Automatic Classification Algorithms for CT Images,” Sensors, vol. 19, no. 1, p. 194, Jan. 2019, doi: 10.3390/s19010194.
[29] S. G. Armato et al., “The Lung Image Database Consortium (LIDC) and Image Database Resource Initiative (IDRI): A completed reference database of lung nodules on CT scans,” Med. Phys., 2011, doi: 10.1118/1.3528204.
[30] D. Kumar, A. Wong, and D. A. Clausi, “Lung Nodule Classification Using Deep Features in CT Images,” in 2015 12th Conference on Computer and Robot Vision, IEEE, Jun. 2015, pp. 133–138. doi: 10.1109/CRV.2015.25.
[31] W. Shen, M. Zhou, F. Yang, C. Yang, and J. Tian, “Multi-scale Convolutional Neural Networks for Lung Nodule Classification,” 2015, pp. 588–599. doi: 10.1007/978-3-319-19992-4_46.
[32] J. L. Causey et al., “Highly accurate model for prediction of lung nodule malignancy with CT scans,” Sci. Rep., 2018, doi: 10.1038/s41598-018-27569-w.
[33] G. Litjens et al., “A survey on deep learning in medical image analysis,” Med. Image Anal., vol. 42, pp. 60–88, Dec. 2017, doi: 10.1016/j.media.2017.07.005.
[34] O. Ronneberger, P. Fischer, and T. Brox, “U-Net: Convolutional Networks for Biomedical Image Segmentation,” 2015, pp. 234–241. doi: 10.1007/978-3-319-24574-4_28.
[35] K. He, X. Zhang, S. Ren, and J. Sun, “Deep Residual Learning for Image Recognition,” in 2016 IEEE Conference on Computer Vision and Pattern Recognition (CVPR), 2016, pp. 770–778. doi: 10.1109/CVPR.2016.90.
[36] G. Huang, Z. Liu, L. Van Der Maaten, and K. Q. Weinberger, “Densely Connected Convolutional Networks,” in 2017 IEEE Conference on Computer Vision and Pattern Recognition (CVPR), IEEE, Jul. 2017, pp. 2261–2269. doi: 10.1109/CVPR.2017.243.
[37] M. A. Thanoon, M. A. Zulkifley, M. A. A. Mohd Zainuri, and S. R. Abdani, “A Review of Deep Learning Techniques for Lung Cancer Screening and Diagnosis Based on CT Images,” Diagnostics, vol. 13, no. 16, p. 2617, Aug. 2023, doi: 10.3390/diagnostics13162617.
[38] S. Mukherjee, “An Effective System for Medical Image Diagnosis Using Deep Convolutional Networks (CNNs) in Healthcare Sector,” in 2026 14th International Symposium on Digital Forensics and Security (ISDFS), IEEE, Mar. 2026, pp. 01–06. doi: 10.1109/ISDFS69419.2026.11459010.
[39] A. A. A. Setio et al., “Validation, comparison, and combination of algorithms for automatic detection of pulmonary nodules in computed tomography images: The LUNA16 challenge,” Med. Image Anal., vol. 42, pp. 1–13, Dec. 2017, doi: 10.1016/j.media.2017.06.015.
[40] S. Khan, M. Naseer, M. Hayat, S. W. Zamir, F. S. Khan, and M. Shah, “Transformers in Vision: A Survey,” ACM Comput. Surv., vol. 54, no. 10s, pp. 1–41, Jan. 2022, doi: 10.1145/3505244.
[41] N. Thakur, P. Chouksey, A. Sharma, M. Chopra, P. Sadotra, and S. Kumar, “Binary classification of lung cancer using vision transformer models on CT images,” Discov. Comput., vol. 29, no. 1, p. 66, Feb. 2026, doi: 10.1007/s10791-026-09931-z.
[42] Y. Tang et al., “Self-Supervised Pre-Training of Swin Transformers for 3D Medical Image Analysis,” in 2022 IEEE/CVF Conference on Computer Vision and Pattern Recognition (CVPR), IEEE, Jun. 2022, pp. 20698–20708. doi: 10.1109/CVPR52688.2022.02007.
[43] S. K. Chandrappa, S. Paheding, and A. A. Reyes-Angulo, “Unraveling Patch Size Effects in Vision Transformers: Adversarial Robustness in Hyperspectral Image Classification,” MDPI, vol. 18, no. 4, pp. 656, February, 2026, doi: https://doi.org/10.3390/rs18040656.
[44] A. Hatamizadeh et al., “UNETR: Transformers for 3D Medical Image Segmentation,” in 2022 IEEE/CVF Winter Conference on Applications of Computer Vision (WACV), IEEE, Jan. 2022, pp. 1748–1758. doi: 10.1109/WACV51458.2022.00181.
[45] M. Abdar et al., “A review of uncertainty quantification in deep learning: Techniques, applications and challenges,” Inf. Fusion, vol. 76, pp. 243–297, Dec. 2021, doi: 10.1016/j.inffus.2021.05.008.
[46] J. Gawlikowski et al., “A survey of uncertainty in deep neural networks,” Artif. Intell. Rev., vol. 56, no. S1, pp. 1513–1589, Oct. 2023, doi: 10.1007/s10462-023-10562-9.
[47] J. Chen et al., “TransUNet: Rethinking the U-Net architecture design for medical image segmentation through the lens of transformers,” Med. Image Anal., vol. 97, p. 103280, Oct. 2024, doi: 10.1016/j.media.2024.103280.
[48] A. Lin, B. Chen, J. Xu, Z. Zhang, G. Lu, and D. Zhang, “DS-TransUNet: Dual Swin Transformer U-Net for Medical Image Segmentation,” IEEE Trans. Instrum. Meas., vol. 71, pp. 1–15, 2022, doi: 10.1109/TIM.2022.3178991.